ONE Function for the Anterior Cingulate Cortex and General AI

Home , Hippocampus (mythology), Predictive coding

Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Medical Research Archives

RESEARCH ARTICLE

ONE Function for the Anterior Cingulate Cortex and General AI: Consistency Curation Author Knud Thomsen Affiliations: Paul Scherrer Institute Correspondence Knud Thomsen E-mail: [email protected]

Abstract Control is essential in all complex systems serving any purpose, and cognitive control is claimed to fill a pivotal role for the cognition of natural agents. The Anterior Cingulate Cortex (ACC) is a neural structure, widely believed to be involved in cognitive control. In the human brain, the ACC undoubtedly takes a center position and features several peculiarities. It has been implicated in a wide range of tasks ranging from sensing pain and autonomic regulation to high- level executive functions like error monitoring and abstract control. A sketch how this seemingly irreconcilable plurality can be understood as manifestations of only one general process working in diverse contexts on different content is presented and also how this constitutes evidence for a specific cognitive architecture. Going beyond extant proposals for ACC function, the here presented one recommends an embedding into a very general overarching model of cognition. Discrepancy monitoring highlights deviations between predictions derived from memory content and current activations. A process doing this has recently been proposed as central to the 'Ouroboros Model' under the title of 'consumption analysis'. It is claimed that ONE functional account centered on consistency checking and, based thereupon, the overall minimization of discrepancies ("consistency curation and cultivation‖) can parsimoniously explain the plentitude of reported observations for the ACC, thus shedding new light on the neural computations, which form the foundations of cognition and, finally, consciousness. A specific "natural" reconciliation of various current conceptualizations and theoretical models is offered, which points out promising directions for future modelling efforts and attempts to harness the findings generally for artificial intelligence.

Keywords: cingulate cortex, agranular, von Economo neurons, monitoring, conflict, discrepancy, attention, bias, predictive coding, consumption analysis, Ouroboros Model.

Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 2 of 23

Introduction Documented functions of the anterior The anterior cingulate cortex (ACC) is part of cingulate cortex the cingulate cortex, a large medial region The anterior cingulate cortex has been encircling the corpus callosum. It is connected observed being involved in markedly different widely to the prefrontal and parietal cortex as contexts. There is ample evidence for the well as to motor and visual systems. ACC, ACC taking part in cognition, decision here mainly seen as Brodmann's areas 24, 32, making and emotional functions as well as in and neighboring, is one of the central network the regulation of physiological processes, hubs in the human brain according to several such as blood pressure and heart rate. Among definitions (van den Heuvel and Sporns, the key functions ascribed to the anterior 2013; Chaudhuri et al., 2015). The ACC is cingulate cortex are: characterized by a lack of a granular layer IV.  Control Together with the insular cortex, ACC is o Anticipation and preparation home to a peculiar class of neurons, in the before (difficult) task performance observed relative quantities only found here o Attention in the human brain, i.e., spindle cells or Von o Error detection Economo Neurons (VENs). Going much o Learning beyond what is possible to describe in a short o Conflict monitoring position paper, it seems that the anterior  (Regulation of) Emotions insular cortex (AIC) serves similar functions o Stress as the ACC. In particular, AIC has also been o Appraisal hypothesized to work as comparator (Allen et o Bias al., 2016a). While four main subdivisions for o Curiosity the anterior cingulate cortex have been  Pain suggested as serving executive, cognitive,  Consciousness emotional and evaluative functions, extensive evidence of significant overlap between Directly underpinning these functions, regions activated during pain, negative affect, particular anatomical features have been and cognitive control points towards an found in the ACC. integrated adaptive control hypothesis with  Anatomic peculiarities the ACC involved to a large extent in o No granular layer aversively motivated action (Shackman et al., o Von Economo Neurons (VENs) 2011). o Asymmetry Essential to a function centered on comparing new with old content and doing this similarly for real compared to envisioned Without any claim to completeness, selected representations, distinguishable main findings are briefly presented in the following networks have been found lately in human one after the other in an attempt to develop a individuals, differing in their inclusion of coherent perspective and to build up the case hippocampal circuits and exhibiting for an encompassing conceptualization. Such interdigitated lay-outs in several cortical areas is briefly outlined with the Ouroboros Model including neighbors of the ACC (Braga & in the second section of this paper; and how Buckner 2017). this could match with previous proposals and In a self-reflective and self-consistent manner prevailing theories of cognition and following the Ouroboros Model, an overall consciousness is delineated towards the end. sketch is first attempted here before While it is clear that only a coarse sketch can subsequently filling in details (Thomsen, be presented here it is intended to self- 2010). consistently offer a fresh integrative view as

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 3 of 23 well as pointing out promising starting points expectancy; it has been proposed that it is for more detailed investigations and future strongly related to the process of response utilization. selection, which determines subsequent action (e.g., Gajewskia et al., 2008; Scheibe et al., Control 2009). Reversible inactivation of the ACC It seems that one common theme, which is impairs prospective memory, i.e., the linked with the Anterior Cingulate in many anticipation of upcoming correct response tasks, can be captured under the heading of locations, as well as selective visual attention, 'control' (e.g., Paus, 2001). Here, this is i.e., there is increased distraction by task- understood as the truly central function of irrelevant stimuli (Kim et al., 2016). directing resources and actively steering the behavior of an actor aiming to achieve some Attention goal. There is a direct connection to Flexibly shifting the focus and allocating cybernetics' use of the term as a meaningful cognitive resources to where they are required first step in any direction presupposes sensing most urgently can be taken as prime function the current status in a given context. The of attention, which is especially demanded simplest control circuits keep some parameter when routine stimulus → response in a predefined range by checking for associations turn out as not sufficient for deviation/discrepancy and actively steering successful performance. Very coarsely, against any divergence, thus constraining that attention can automatically be drawn to a controlled parameter to its allowed range. feature, a specific location or object by a More advanced control systems steer effectors salient stimulus (bottom up), and it can be depending on the current status and the allocated (top down) as a result of internal intended condition. The ACC has been (cognitive, often conscious) processing. claimed to be important for interpreting Anticipations guide attention, e.g., bias outcome information with respect to the sensitivity, for specific features while current task context to guide action selection attenuating responses to disturbances from (Walton and Mars, 2007). The observed ACC outside the actually relevant (feature-) area; activation is specific to the detailed conditions i.e., signal / noise is enhanced. In accordance and overall context (Braem et al., 2016). with this two-faced characteristic, attention not only directs activity, it is also an Anticipation immediate consequence of many (alerting) The ACC has often been implied in processes. The ACC has been reported to anticipatory activity (e.g., Murtha et al., form part of a distributed attention network in 1996). Enhanced activation has been reported the human brain (e.g., Bush, Luu and Posner, during preparation for difficult tasks, and, 2000). "Attention for action in context" has especially when a new task-set is demanded been suggested as most adequate description with changed requirements, often after a of ACC functions (Luu and Pederson, 2004). 'reset' ensuing a previous attempt, which did ACC activity predates excitation of neurons not suffice to reach a goal. Focusing on the in the locus coeruleus, which in turn causes actually relevant features is essential for changes in pupil diameter as a response to avoiding interference and errors. This can be surprise and cognitive effort (Joshi et al., seen as filtering and noise-suppression, i.e., 2016). Lesions of the ACC have highlighting content and concentrating on it. (surprisingly) small effects. Monkeys with Strong and clear anticipation for a simple ACC lesions were little impaired in updating stimulus has been found to enable fast visual their choices; they displayed difficulties in awareness of its presence (Railo et al., 2015). sustaining a correct response in a changing ACC activity varies with changes in response environment and took into account only the

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 4 of 23 immediately preceding information (Walton Reward based learning theory and Mars, 2007). Relating to a vastly Errors need not be only seen as negative; they generalized facet of attention, ACC has been can trigger immediate correction or hypothesized to supply a "global energizing improvement and, on a longer time scale, also factor", which stimulates action and decision learning. Thus, they point and pave the way making. When the anterior cingulate cortex is for better performance in the more distant severely damaged, this can result in akinetic future. Reward based learning theories see the mutism (Holroyd and Yeung, 2012). Dorsal anterior cingulate cortex as serving these ACC and lateral prefrontal cortex appear to needs (Ridderinkhof et al., 2004). Effort, play critical roles in acts of volition (Mulert et which is amplified after an error, is linked to al., 2005; Gmeindl et al., 2016); activity there enhanced ACC activation. There are is reduced during hypnosis (Jiang et al., significant individual differences in attitudes 2016). and in activations evoked by errors (Moser et al., 2011). Regions in the dorsolateral Detection of errors & surprise cingulate cortex were found to be especially A role for the ACC in the detection of errors involved in the implementation of fast during task performance has been reported in adjustments in a close coupling to lateral a large number of studies (e.g, Bush, Luu and prefrontal cortical areas (Garavan et al., Posner, 2000). There is overwhelming 2002). Errors have to be remembered in order evidence, which links a centrally sensed to avoid their repetition. Memorized values in evoked scalp potential observed after the turn inform decision making. The anterior commission of an error "ERN" or "N2" to cingulate cortex has been claimed as essential activation in the anterior cingulate cortex for the selection of actions, being also a main (e.g., Falkenstein et al., 1990; Gehring et al., target of dopaminergic inputs from the ventral 1993). A potential very similar to the error tegmental area (VTA) of the brain reward negativity is evoked at longer latency when system, active for previously pleasurable subjects are told that they have made a memories (Paus, 2001). In the other direction, mistake (e.g., Holroyd, Dien and Coles, the ACC appears to first signal some results 1998). Some activation in the anterior to the reward system, to the amygdala and cingulate cortex can be detected even when an also to the hippocampus for establishing individual is not aware of his error or distinct memory entries (Parkinson et al. conflicts but awareness increases that activity 2000; Pourtois et al., 2010; Brunce et al., (Luu and Pederson, 2004). The anterior 2013; Thomsen, 2017). Later on, for memory cingulate cortex signals not only deviations to retrieval, direct reverse connections will the negative but also to the positive: better contribute relevant information like than expected outcomes also activate the concerning context and expected rewards for ACC (Ferdinand et al., 2012; Shenhav et al., a task-set for its new handling by the ACC 2013). In well-known oddball experiments, (Holroyd and Coles, 2002; Rajasethupathy et ACC activation is quite generally observed al., 2015). when an expectation, e.g., in a stream of stimuli, is violated; this can be simply Detection of conflicts described as surprise (Crottaz-Herbette and Reliably sensing conditions under which Menon, 2006). Looking in detail, the evoked errors are likely to occur is essential for potentials for new versus deviant items in a avoiding them. ACC activity has also been sequence are similar but differ in their fine observed during correct responses under timing and topographies (Noyce and Sekuler, conditions of increased response competition 2014). in the same region as in cases when errors actually occurred (e.g., Carter et al., 1998;

Botvinick et al., 2001). ACC activity is inhibition of unsuitable cognitions or intensified and prolonged in conflict trials that emotions. The important point would be that require revision of a prepared response plan "monitoring" necessitates a comparison and (e.g., Gajewskia et al., 2008). When there are some inevitable type of activation to start conflicting response tendencies at the same with. Not only has this been described by time the anterior cingulate cortex appears to Sigmund Freud (1900), there are also recent determine which should be followed (e.g., reports that suppressed thoughts often surface Holroyd et al., 2004). Conflict, quite in dreams (Wegner et al., 2004). generally, has been found to induce negative affect (Braem et al., 2016). Emotions and their regulation Committing errors is unpleasant, probably Cognitive Dissonance more so than a mere feeling of inconsistency. When people are confronted with information The amygdala, which is amongst others that is inconsistent with their beliefs they feel tightly connected to the ACC and insula, has cognitive dissonance. Holding two or more been strongly implicated for mainly negative contradictory beliefs, conflicting ideas, or emotions, in particular for the formation and values at the same time causes mental stress the storage of memories associated with and discomfort, which has been described emotional events (e.g., Etkin et al., 2011). In a long before any involvement of dorsal rare case where ACC and amygdala activation anterior cingulate cortex in these conditions could be studied intra-cranially, activity had been observed (Festinger, 1957; van Veen elicited by novel stimuli in the ACC always et al., 2009). Disgust or watching unfairness, preceded amygdala activation (Pourtois et al., which activate similar ACC areas, might be 2010). Later on, memorized emotional tags characterized as falling into a related category are employed in decision making (e.g., Paus, (Corradi-Dell`Acqua et al., 2016). ACC 2001). In addition to first establishing an activation from ―low level‖ conflicts is emotional tag, and thereafter using diminished if subjects engage in the memorized evaluations for decisions and affirmation of ―high level‖ values (Proulx et action, the ACC appears to be involved also al., 2012). in regulating emotion in a manner following the same lines as for steering other behavior Ironic rebound (Compton et al., 2008). This implies second- Tasks demanding somewhat self- order emotions and subsequently second- contradictory effort like thought suppression order coping and behavior adaptation. Cells in appear to offer a particularly effective way of the anterior cingulate have been found to provoking cognitive conflict or dissonance. signal rewards, both, for experienced and for Many studies have shown that "ironic fictive outcomes (Hayden et al., 2009). rebound" arises after individuals strived to Successful (and more so for difficult) conflict suppress particular thoughts, attitudes, beliefs, resolution has been demonstrated to provoke or emotions (Wegner, 1989). The fact that positive affect (Schouppe et al., 2015). suppressed cognitions and feelings resurface, Beyond the involvement in temporary even more intensely than before, has been emotions, the long-term trait of subjective explained by a two component model of happiness was found to be correlated with cognitive control. While a "monitor" is grey matter density in rostral ACC hypothesized trying to detect the suppressed (Matsunaga et al., 2016). content, an "operator" inhibits them. According to Wegner, Wenzlaff, and Kozak Appraisal and Bias (2004), the anterior cingulate cortex might Appraisal theories claim assessments, i.e., underpin the operator, by facilitating the appraisals along certain selected dimensions,

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 6 of 23 as essential and ground-laying components of Randles et al., 2016). Recently, empathy emotions (Moors et al., 2013). Affect delivers reduction as side effect has been reported in (often valid) information for an agent on the subjects consuming the same common pain one hand side (Schwarz and Clore, 1983), killer (Mischkowski et al., 2016). While the and, on the other, at (about) the same time, ACC has earlier been implied as part of the emotions bias perception and direct action to "pleasure system" in the brain, - subjects relevant directions (Ciompi and Panksepp, implanted there with electrodes kindle 2005). Positive mood induces preparatory themselves - , consensus in the meantime activity in the ACC, actually biasing problem appears to see exciting the ACC as producing solving towards creative insight solutions ―want-‖ rather than genuine pleasurable states (Subramaniam et al., 2008). The ACC and (Berridge et al., 2015). frontoinsular cortex are the two areas, which have been found to be consistently activated by different types of jokes (Watson et al., Consciousness 2007). Curiosity, emotions, pain, pleasure and empathy are usually tightly associated with Curiosity awareness and conscious perception, and, in Differing in at least the non-definitiveness or - particular, the ability of a subject to report permanence of its objects from more genuine about it. Furthermore, evidence has been affects, curiosity often is also considered an found for a close relationship between emotion fueling motivation. It has been linked conscious effort and anterior cingulate cortex to gaps in knowledge and understanding activity (Mulert et al., 2005). Patients with (Loewenstein, 1994). Humans and animals diverse disorders of consciousness showed actively seek to reduce uncertainty, which is diminished ACC activity during the experienced as disturbing. This goes as far as perception of self-related stimuli (Quin et al., humans' inherent desire to resolve uncertainty 2008). As just one more exemplary hint at can actually induce them to perform specific clinical aspects, it has been suggested that actions despite expecting direct negative dysfunction in attention-deficit/hyperactivity consequences (Hsee, 2016). Induction of disorder (ADHD) is linked to decreased perceptual curiosity has been shown to connectivity between the dorsal anterior activate the ACC (Jepma et al., 2012). cingulate and the precuneus (Castellanos et al., 2008). Dorsal cingulate cortex and the Pain, Pleasure and Empathy precuneus, both, are close neighbors to the One can claim that errors and conflict are ACC (Cavanna 2007). Their activity has been painful and that consistency monitoring is the reported to tightly correlate with seamless and natural expansion of checking consciousness; functional integrity of for bodily integrity and the wellbeing of any Posterior Cincgulate Cortex connectivity agent; the ACC has been implicated in a appears necessary for maintaining network sensing pain and also coping with it consciousness of the external environment (Hsieh et al., 1999). There is evidence for at (Herbet et al., 2014). least some overlap between cingulate and insular areas devoted to nociceptive and Anatomical peculiarities empathic pain (Zaki, et al., 2016; Corradi- Studies in monkeys indicate that the ACC is Dell`Acqua et al., 2016). Consistently, a very widely connected to prefrontal, orbitofrontal, popular pain killer has been found to attenuate insular and anterior temporal cortices as well error evaluation; especially a reduction of PE, as to the amygdala, hypothalamus and various the positive potential usually following ERN, thalamic nuclei (Öngür and Price, 2000). has been observed (Boldt and Yeung, 2015; Similar to many areas in the human brain, a

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 7 of 23 hierarchical ordering is observed in the Cingulate cortices have been claimed to medial prefrontal cortex with a rostro-caudal occupy central positions in a wide-ranging gradient of abstraction in correspondence to and coarse default mode network (DMN) and the connected regions (Zarr and Brown, in a salience network. Here, it shall be 2016). Compared to other areas, the anterior highlighted, that not only exciting but also cingulate cortex exhibits some features, which dampening influences are exerted by the are not found at all outside this region, or not ACC; in particular, the cerebellum appears to found in similar extensions or configurations. be inhibited by ACC activations.

Agranular Laterality, source of hemisity Conventionally, the anterior cingulate cortex While many monitoring processes can run in is seen as constituting a less advanced version parallel, ultimately, overall control for any of cortical circuitry as the ACC does not have consistent behavior has to be somehow a granular layer IV. Interestingly, it shares bundled in one entity. On an anatomical level, this feature with the neighboring motor the ACC seems to offer a good candidate cortex, and it has been hypothesized that ACC basis as it is one of very few structures in the actually is an evolutionary late extension, brain, which exhibit consistent differences in optimized for specific tasks providing output the two hemispheres with the dominant one from the top of a processing hierarchy containing significantly more neurons; this (Allman et al., 2001). Efferent connections of has been taken as support for a concept of the ACC connect to superficial layers 1 and 2 hemisity (Morton, 2013). The idea here is that in eulaminate cortex, which indicates the dominant executive system, the basis for modulatory influence there (Barbas, 2015). the 'will' of an individual, must physically reside in one hemisphere. Von Economo Neurons, Spindle Cells There is no doubt that spindle cells, Von ACC Functions from the point of view of Economo Neurons (VENs), are a recent the Ouroboros Model addition to cerebral circuitry, restricted to In order to elucidate the participation of the humans, apes and a few more animals owning ACC in each of the highlighted functions, the large brains (Allman et al., 2001). The cell main tenets of the Ouroboros Model will first bodies of VENs are about 4 times as be introduced briefly in the following. In a voluminous as more common pyramidal fully self-reflective and self-consistent neurons, which suggests that they bear large, approach adhering to the principles of the rapidly conducting axons. They are also Ouroboros Model, the aim here is to initially characterized by much more locally restricted outline a coarse but overarching sketch on a dendritic arbors. The first feature can be conceptual level before delving into more interpreted as enabling the rapid transmission intricate details and finally elaborating of strong signals over long distances, whereas mathematical formalizations, quantitative the second perfectly fits with the accurate simulations and some utilization (for sensing of tightly localized activations and implementations) in the future. also with a special computational relatively simple function (Watson et al., 2006). The Ouroboros Model The Ouroboros Model has been introduced ACC Connectivity recently in an attempt to explain a wide range In a pattern of wide functional connectivity of of findings pertaining to cognition and the ACC, negative correlations for activities consciousness of natural and also artificial have been found between ACC and some agents (Thomsen, 2010-2015). The subcortical circuits (Margulies et al., 2007). Ouroboros Model offers a widely applicable

―algorithmic backbone‖; it has its starting dumps" of the type proposed for flashbulb point in, and it puts its focus on, every-day memories (Brown and Kulik, 1977). (human) experience and commonsense A rather well-defined parcellation of memory reasoning. There are only two basic content is held as most important for the ingredients, which are claimed as responsible proposed processes, which work on this very in their proper combination for the core of all basis; it allows the confined activation of (human) perception, cognition and action complete entries from only fragments of the including, e.g., memory retrieval and problem original content, i.e., pattern completion, the solving: generation of anticipations and relevant • Action- and memory structure predictions, and, at the same time, an (organized into schemata as basic activated frame enables straightforward building blocks) monitoring of current activity in the light of • Cyclic iterative processing (with previous experience. From a finite set of ‗consumption analysis‘ as the main process in building blocks practically unlimited diverse a loop) concepts can assembled. The decisive novel step is to explicitly ―make Directly relevant to questions of experience the wheel turn", i.e., the results of one and self-consciousness, such snapshots of all processing cycle are dynamically used to related and strong activity in a brain will also actively control the next iteration, steering an contain and link features of the actor herself. overall advantageous course over time These can span many levels of abstraction, comprising the incessant autocatalytic including bodily signals, emotions, generation of new memory content, self- motivations, as well as personal goals; guided to where the need arises. somatic markers are but one example, while qualia and higher order thoughts follow suit Action and Memory Structure (Harnad, 1990; Damasio, 1996; Rosenthal, The Ouroboros Model holds that memory 1997; Thomsen, 2011b). entries (like for episodes or actions) are organized into cohesive chunks called Cyclic Iterative Processing schemata; these are distinct combinations of The Ouroboros Model is built around a self- features, which have been experienced at least reflective and self-referential recursive once before as belonging together (Thomsen, process with alternating phases of data- 2010). acquisition and -evaluation, comprising the New entries as a record of any current main steps: ... anticipation, action / activation are preferentially committed to perception, evaluation, and new anticipation, memory at times marked as important by .. . These steps are concatenated into full consumption analysis. Building blocks repeating cycles evolving over time. In the include whatever representations are active at picture and words of medieval alchemists, the the time when such a 'snapshot' is taken, serpent called the Ouroboros devours its own comprising sensory signals, as well as tail (Thomsen, 2010). Anticipation can be abstractions, i.e., previously laid down seen as lying at the very heart of the representations encompassing also features Ouroboros Model. relating to probable transients and causal A central monitor-process termed structure, just as prevalent emotions and 'consumption analysis' is intermittently longer lasting moods. At subsequent checking how well expectations triggered at occasions, newly bound structures will be one point in time fit with successive employed in the same way as earlier activations. established schemata. Only in extreme cases The outcome of this monitoring, a universal these 'snapshots' will be full-fledged "core form of consistency checking, generally

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 9 of 23 marks discrepancies and leads to impacts on In the light of the above it seems obvious to various (time-) scales: locally, it highlights see the ACC as the substrate for the working ―open slots‖, i.e., attributes that belong to the of consumption analysis. Not only do one selected schema (task set) but are not yet especially diverse discrepancies lead to confirmed by currently available input, and, activations but also this triggered activity more globally, it provides feedback for an exerts control over many other areas (e.g., actor on how matters develop as a basis for Gajewski et al., 2008). In the following, the autonomously directing future steps and the different facets of ACC function are meaningful allocation of (attentional) commented as manifestations of the resources. Ouroboros Model under the same headlines In the conception of the Ouroboros Model, an [examples] as in the previous lay-out section. overall recursive process progresses in real "Consistency Curation" in the ACC can be time in a piecewise and predominantly serial seen as control on the basis of "time-stamped fashion while concatenating stages, which are carbon copies": actual incoming percepts (or often intrinsically parallel, into one principal activated memory traces) are compared with a loop (Thomsen, 2010). The overall process currently selected schema, goal or plan and obtains a self-organized direction and associated anticipations and expectations prioritization towards what is currently derived from previous experience. Gaps and experienced as relevant and also expected to deviations of all possible types with respect to be so in the future. Consumption analysis an active schema direct attention to details or delivers also a global measure for the reset the whole context in a hierarchically goodness of fit between anticipations and the staged series of escalation steps; in actual status, and, amongst others, it not only conditions, where an expected change is triggers the allocation of attention, but gives already implemented (during task switching), rise to emotions, determines what is put into no extra ACC activation is observed (long-term) storage and calls for conscious [Anticipation, Attention, Control]. stronger engagement in cases where According to the Ouroboros Model, for automated responses or habits do not suffice solving a task, first a schematic anticipation is (Thomsen, 2011). This directly opposes any activated, similar to what has been described "echo chamber" effect: the emphasis is on more than a century ago by Otto Selz (1913). widening the mind frame and not on This biasing of suitable schemata will be ingraining prejudices. more pronounced with increasing task Comprising and actively combining diverse difficulty, e.g., when (response-) conflicts are characteristics, the Ouroboros Model can be looming large and preparation before a seen as schema-, i.e., model-based as well as (difficult) task is required [Anticipation]. data-, i.e., input- or event-driven, and also as Matching an expectation with incoming value-guided, as values and goals are just activation, i.e., 'consumption analysis', examples of peculiar high-level schemata. highlights discrepancies and open slots; the Bottom-up and top-down activity unfolds Ouroboros Model holds that to these, incrementally in iterative cycles progressing (attentional) resources are allocated by in time, this interplay implementing, enhancing the representations for anticipated effectively, Bayesian mechanisms and features [Conflict monitoring, Attention, performance (Thomsen, 2010). Bias]. If the results turn out as not satisfactory, i.e., How the Ouroboros Model could fit with discrepancies are exceeding a threshold, this the reported functions of the Anterior causes stronger activation and possibly a Cingulate Cortex "reset" [Error detection].

Discrepancies between expectations and and one prime function of (dream-)sleep has available material can be of very diverse been proposed as taking care of these [Ironic character; filling-in an open slot might fail, rebound]. there might be no fitting material or also There will always be open slots, and agents overflow. Checking for deviations will differ in their background, interests, biases include a time-dimension, possibly quantified, and acceptance thresholds for triggering and also (inherited) emotional tags as diverse actions in order to reduce the attributes of schemata, – just as any other associated tension [Curiosity]. features, going much beyond simple single Discrepancy monitoring can be seen as attribute occurrence. "Surprise" is seen by the "cognitive" extension of a very fundamental Ouroboros Model as a generalization of function, which ensures that a body is not "error", i.e., in particular, not necessarily with taking harm by moving in a way, which does negative connotation [Surprise]. not work [Pain]. Activations pertaining to the agent herself are The Ouroboros Model is centered on nothing special in this respect; they just (self- consumption analysis, and the underlying referringly) comprise features with that structure "at the (/one) top of the brain" (the special content, thus laying the ground for ACC) focused on comparing activations and self-reflectivity and full self-consciousness at biases would expectedly be different than the the top [Consciousness]. neural substrates involved in intermediate The Ouroboros Model posits that episodes steps [absence of granular layer]. marked as special (positive as well as For the detection and distinct identification of negative) are preferentially submitted to deviations and differences, an appropriate memory; the ACC has indeed been found sensing neuron should base its triggering on a poised to mediate signal transfer into and out tightly confined (cortical) input (region); from of the hippocampal formation (Thomsen, the claim that the comparison extends widely 2017) [Control, Learning]. over diverse content it follows that Not only feedback for the endpoints and discrepancies subsequently have to be extremes in this process are of interest [Pain, communicated fast to probably far-away Pleasure], but also how overall activity cortical areas [Von Economo neurons progresses towards a resolution and how (VENs)]. deviations are resolved (i.e., [Cognitive Antithetic and/or complementary to the Dissonance] signaled and reduced) contains specific modulation of cortical areas would be very valuable information [(Regulation of) interpolating and averaging; an observed Emotions, Stress, Appraisal]. Important negative correlation between ACC activity matters will draw more resources, the faces and the cerebellum thus dovetails with the and behavior of conspecifics providing tenet of the Ouroboros Model that sees the prominent examples [Empathy]. "New" cerebellum as general purpose interpolator emotion signals are continuously computed (Thomsen, 2014) [connectivity]. from a measure how well expectations based Here, it shall be stressed that there is another on old memories are met at any particular way in addition to structural dominance in point in time, while "inherited" affective tags one spot to ensure overall consistency, as an form an integral part of previously established alternative or, most likely, in addition: instead schemata [Feeling]. of a location in physical/topological brain- With limited resources available and under space, the seemingly indispensable "top unity severe time constraints, full harmony between of command" can be tied to specific points in anticipations and the results actually achieved time in a process-centered account, and will hardly ever be reached for real-time something similar might be said concerning performance. "Left overs" are accumulating, the "unity of consciousness" as experienced

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 11 of 23 by healthy subjects (Thomsen, 2011b). induced ego dissolution (Tagliazucchi et al., Taking the time-dimension into proper 2016). After psilocybin infusion, decreased account allows to accommodate the finding alpha activity has been observed in human that there appear two distinct brain subjects in the precuneus and posterior mechanisms involved in conscious versus cingulate cortex (Carhart-Harris et al., 2014) subliminal error detection; (Charles et al., [Consciousness]. 2013; Crottaz-Herbette and Menon, 2006) A unifying model of the medial prefrontal [Asymmetry, Consciousness]. cortex as action-outcome predictor, the With wide-spread activation, as hypothesized "predicted response-outcome" (PRO) model, being essential for conscious action (High which comes relatively close to the Personality Activation, HOPA), more and comprehensive view advocated by the diverse areas of the cingulate cortex sense a Ouroboros Model, has been proposed recently deviation between anticipations and actual by Alexander and Brown (2011). Their performance (Thomsen, 2011b). One can construct of 'negative surprise' is claimed to argue that finding a stepwise change in error occur for cases in which actions do not negativity for unconscious versus conscious produce the expected outcome when error response just highlights the difference comparing many associated features in between ―local‖ and ―global‖ excitation in a parallel, ─ all of them connected in a human brain, the latter including posterior delimited schema according to the Ouroboros areas producing PE, likely corresponding to Model. This group found distinct regions the awareness/involvement of an actor signaling the violation of expectancies and (Charles et al., 2013; De Cul et al., 2009; their degree (Jahn et al. 2014). ACC Jahn et al. 2014). The Ouroboros Model sees processing had before been claimed to yield at consciousness as developing and manifesting least two qualitatively different types of itself over longer times in shades of grey; ─ prediction errors: as a Bayesian surprise for one and the same individual at different signal and a signed prediction error, i.e., an occasions and conditions, and also to evaluation outcome (Ide et al. 2013). (strongly) varying degrees in different species. This does not preclude a sharp Links to Selected other Models of transition between states (modes) of an actor Cognition and Consciousness at any given occasion (Sergent and Dehaene, 2005) as the first relates to a maximum Predictive Coding available capacity/capability whereas the Predictions and how they are met lies at the second to a nonlinear transition from partly / heart of the Ouroboros Model; a comparison local to global activation to the extent with other accounts putting their emphasis on possible (Bayne and Hohwy, 2013). There is predictions thus is obvious. "Predictive evidence for switching between modes after Coding" is the brand name of a whole family crossing a threshold, similar as has been of models receiving a lot of interest lately. found for simple perceptual decisions when The common hypothesized main claim of accumulating sensory evidence (Kang et al., these models is that rather than forwarding 2017). positive signals for the occurrence of any It is important to note that the quasi-global specific feature, the decisive ingredient is activation hypothesized by the Ouroboros error back-propagation. According to these Model as ground laying for consciousness, models, activity in higher areas predicts HOPA, is still an orderly and constrained one, excitation in lower ones, and mainly, even in some contrast to increased rather only, the deviation between this prediction indiscriminate global functional connectivity, and the actual activation ("the residual which has been found to correlate with LSD- prediction error") is transmitted in the forward

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 12 of 23 direction between cortical areas (e.g., Friston, iterative cycle, including, in particular, the 2010). An associated "free energy principle" output of consistency checking as far as it has has been proposed as unifying basis for been completed at a specific point in time. cognition. Goodness of fit is calculated in intervals, While standard predictive coding posits taking into account all current activations. inhibitive feedback from higher to lower tiers This can explain results interpreted as in the coding hierarchy, it is possible to supporting standard predictive coding and at achieve basically the same with excitatory the same time why no separate populations of feedback links (Spratling, 2008); seemingly "error-neurons" as postulated are found. Not contradictory predictions by more standard properly inhibited, subliminal activations can predictive coding accounts and other well- be smuggled in: e.g., unconsciously elicited known biased competition models can in fact disgust thus will influence an assessment by be harmonized as different implementations diminishing positive evaluations and the of the same abstract mathematical idea. confidence in them, while strengthening Predictive coding has its way of dealing with doubt if already prevailing (Allen et al., (perceptual) uncertainty: "error-precision". 2016b). The claimed function can be seen as in principal similar to the output of consumption Searching for canonical computations analysis directly reflecting a goodness of fit as performed by the cerebral cortex, feedforward hypothesized by the Ouroboros Model when selectivity and recurrent gain control are concentrating on relevant attributes. emerging (Miller, 2016). In order to avoid Currently favored predictive coding accounts run-away excitation, input is claimed to best with their posited reciprocal connections be attenuated leaving only some residual net between stages in a strict encoding hierarchy excitation. Competition between neutrons of offer clear progress over a one-directional the same stage certainly helps in sharpening linear feedforward chain of feature detectors. responses. But, they still stress a (bi-)linear succession of Brains without doubt adhere to a general processing stages. The layout of the efficiency principle avoiding unnecessary Ouroboros Model is offering additional energy use and associated cost; still, forward- benefit to predictive coding by expanding the directed signal- and evidence-transfer as structure from a primarily linear extension to ground laying function seems more natural its full possible breath. Conceptually, splitting than focusing almost exclusively on errors, that stream in two and separating the branches which often cannot tell much, especially not in time for cyclic succession, allows for wide for new percepts or in completely new iterations, with higher levels able to also situations. The observation and necessity of directly impact lower ones (in addition to communicating evidence in a forward more local feedback connections); this adds direction has been pointed out repeatedly over tremendous flexibility. Cyclic activity unfolds time. "Error" is a relative concept, which over time, and the natural picture is one of presumes some "correct" reference frame, iterations: activity at any one point in time context. To really expel a tacitly assumed building on the (recent) history and easily homunculus or "Lufthaken", it would be incorporating many other relevant (or required to explain why and how neurons influential) factors in parallel. know that they represent (conflicting) The point of the Ouroboros Model is, that, in alternatives (Botvinick et al., 2001). The addition to local effects of habituation and Ouroboros Model does exactly this when feedback, activity is globally coordinated and contrasting memory-derived expectations inhibition (as well as positive biasing) is with current actual activations. primarily updated and effective after a full

Quenching, i.e., a top down signal, which and Menon, 2006; Grotheer and Kovács, silences a predecessor stage, will be required 2016). On a global scale, whenever an error primarily for detector / input- stages; there are is detected this first needs encompassing temporal receptive windows, and a hierarchy inhibition of current activity before a new bias of times is observed: ACC features the can be disseminated (Shen et al., 2015). longest (Chaudhuri et al., 2015). Amongst others, three problems for the Generally, progress can be expected from predictive coding theory of attention have advances in imaging methods, which can been raised by Ransom and Fazelpour (2015), finely distinguish the extent of activations, who argue that predictive coding fails to their signs (excitatory versus inhibitory) and model endogenous feature-based attention, also their timing. A good prediction based on that it is unclear how non-perceptual forms of a well-established schema, according to the attention like to one‘s thoughts might be Ouroboros Model, would result in relatively accommodated, and, that it does not explain limited activation because only few dedicated the influence of affectively silent objects. neurons with clear response assignments are According to the Ouroboros Model in short, needed. Representations sharpened by ACC activation can highlight whatever is expectation would require less overall coded (as a feature or action) in a brain, not (gamma) activation but could still transfer the necessarily only perceptual attributes; many same amount of information as available from complete objects and features taking part in a wide population excited in the absence of schemata will have associated specific guiding top-down information (Kok importance/emotional (relevancy-/saliency-) et al., 2012; Zhang et al., 2015). This is about tags "inherited" from previous encounters, what has been found as "prediction which assure their strong impact on the suppression" (Crottaz-Herbette and Menon, ongoing processing as one possibility, and/or, 2006). also, if not anticipated as part of the active In the real world, any actor has to face schema, as they will stand out from the dynamic changes happening all the time. It is expected, and they will activate the ACC. The important to keep track of the development, same applies for novelty in general. Curiosity i.e., by noting what has already been sensed, has been shown to be a strongly motivating used and classified, contrasting this with drive accompanied by ACC activation, quite novel percepts. In order to avoid getting stuck contrary to a naive prediction of standard in repeated considerations of one and the predictive coding that an agent would prefer same input, consumption analysis effects also to quietly sit in a dark room (e.g., Froese and the tagging of stuff already exhaustively dealt Ikegami, 2013). An approach maximizing with. This is very important at many levels predicted information gain in a Bayesian and will be implemented via inhibition of the framework to direct curiosity-driven respective earlier stages leading to a exploration of an embodied agent in action- suppression of their continued response. This perception loops has been claimed to stand in implements well-known "inhibition of stark contrast to the free energy hypothesis return"; misapprehended, this could be (Little and Sommer, 2011) but is, in fact, interpreted as error feedback. Repetition efficiently outlined with the Ouroboros suppression and expectation suppression of Model. early sensory areas both are related to enhanced coding efficiency. They interact but Behavior in Time can be separated among other things on the Most of the time, the world is changing, and basis of their timing; the second occurring this has to be taken into account by any agent. later and being obviously the effect of more The Ouroboros Model emphasizes a global distant top-down influences (Crottaz-Herbette frame and its compartmentalization into

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 14 of 23 schemata, which include also slots for fast gamma synchronization is an early timing(-)attributes. On this basis, an orderly prominent example (Gray et al., 1989). process of consumption analysis unfolds in Gamma oscillations have been claimed to be time in iterative cycles. "Funneling" all nested in slow theta rhythms (Lisman and activity in a healthy human brain through a Idiart, 1995.) In a 'match-and-utilization- global consistency checking stage, comprised model' MUM, gamma-band activity spaced in mainly by the ACC, appears to dovetail nicely time at theta-synchronous intervals has been with what is known about its function. proposed to, firstly, accompany the There is electrophysiological evidence that comparison of memory content with stimulus- ACC activation modulates prior probabilities related information, and, thereafter, promote as part of a preparatory process (Scheibe et the utilization of signals derived from that al., 2009). When there is an expectation, an comparison (Herrmann et al., 2004). These attended stimulus will be processed ideas have been elaborated for visual search preferentially whereas unattended stimuli, not where the slow oscillation, interpreted as being part of that activated schema, will be reflecting top-down influences, initially is suppressed (Todorovic et al., 2015). In the reset and synchronized to the fast gammy light of the Ouroboros Model, expectation and cycles representing individual items (Sauseng attention are about the same, the labels just et al., 2010; Sauseng et al., 2015; ). Quite referring to different stages of cyclic similar processes, basically swapping fresh processing, i.e., more generally at the outset sensory signals for their reinstatement from and directed at specific relevant slots during memory entries, have also been proposed later cycles, respectively. The ACC has been (Nyhus and Curran, 2010; Zhang et al., 2015). found to effectively adjust the distance to the Synchronized gamma and theta cortical decision threshold in a context according to activity will enhance the coupling to the the current amount of available hippocampus and long term episodic memory predictive/relevant information (Domenech, (Colgin 2015; Bunce et al., 2013). Externally 2010). Not only are specific slots in a schema produced prediction errors, like endogenous biased, the mere announcement of potentially ones, have been shown to promote one-shot changing respond-demands provokes changes learning (Maryott et al., 2011). An in medial frontal activity in the absence of interpretation of the ERN as related to errors or response conflict (van Noordt et al., ongoing EEG processes, rather than being a 2015). Neural signatures of subjective value discrete and separate response, has gained comparison during decisions requiring wide support; in particular, frontal midline reward─effort trade-offs in the ACC have theta rhythms have been found to reflect been documented recently (Klein-Flügge et alternative activation of prefrontal and al., 2016). anterior cingulate cortices in humans (Asada In a large-scale dynamical model of the et al., 1999; Luu et al, 2004; Cavangh and macaque neocortex based on quantitative Frank, 2014; Voloh et al., 2015). Particularly connectivity data a hierarchy of timescales in preparatory states, medial prefrontal cortex naturally emerges: sensory areas show brief, showed a phase-lead relative to parietal areas transient responses to input (appropriate for (Phillips et al., 2014). Surprise disrupts fast sensory processing), while association cognition engaging the same fronto-basal areas integrate inputs over time and exhibit ganglia suppressive mechanism as active in persistent activity (suitable for decision- outright action-stopping (Wessel et al., 2016). making and working memory) (Chaudhuri et In a simple oddball task where both, al., 2015). functional Magnetic Resonance Imaging Brains are teeming with periodic signals at a (fMRI) and Event Related Potentials (ERP) wide span of frequencies. Object binding by methods with high time-resolution were

Copyright 2018 KEI Journals. All Rights Reserved http://journals.ke-i.org/index.php/mra Knud Thomsen. Medical Research Archives vol 6 Issue 1. January Issue. Page 15 of 23 employed, primary sensory regions have been behavior by means of spatiotemporal spike found to generate a small mismatch signal coding; downstream receivers are unlikely to about 50 ms prior to feedback from the ACC act as simple neural integrators, which just and a large signal 60 ms thereafter (Crottaz- sum up their input (Logiaco et al., 2015). Herbette and Menon, 2006). The following would be a condensed sketch How the above could be implemented in of activity during cognition along the lines of neural circuitry is the subject of ongoing the Ouroboros Model / neural activity with a research. A promising example has been focus in ACC during cognition in a healthy presented by Luduena and Gros (2013), who (human) brain: show that in an unsupervised feedforward 1. For an arbitrary start, fast gamma activity neural network following an anti-Hebbian is evoked locally by a sensory signal in an learning rule a comparator-function can early cortical area. Theta recurrent activity emerge under strictly local rules through self- is kindled, and through the ACC this organization, which can signal the grade of biases a whole schema from memory, similarity between unrelated input streams enhancing the chance of additional local even in the presence of noise. fast oscillations in areas, which represent all expected associated features, for this Conclusion and Outlook context or task set. The Ouroboros Model, at the moment, 2. Consumption analysis is implemented in delivers a still very coarse-grained picture but the ACC comparing expectations (arriving roughly consistent with all of the above (-- top down) and actual available input and, where not, these would be exactly the (arriving bottom up). points to direct attention to). A schematic 3. In case the anticipated slots are easily frame has to be valid for a rather long time, filled (expectation suppression) and enabling the filling-in of attributes; top-down activity proceeds as expected, consumed (preparatory stage-setting) signals are constituents are inhibited (inhibition of therefore associated with lower frequencies return), and new input is selected. (Theta). Individual components, comprised 4. If gaps cannot immediately be adequately themselves of contributions from diverse closed, for these, open slots' biases will neural, e.g., sensory, populations bound by increase until eventually a threshold is fast gamma oscillations, can be understood as reached and a reset is triggered. Especially bottom-up (feedforward) signals. Contrary to evident for motor acts, ongoing activity repeated proposals in the literature, theta has to be interrupted. Thereafter a new oscillations and embedded ERPs are seen as schema has to be selected and put into effecting control and not merely indicating a force (ERN, goto1.). need for control (Cavangh and Frank, 2014). 5. Forward and backward messages are If (response) conflict cannot be solved transferred at different phases of the quickly, this will manifest in increasing ACC overall theta cycle, and their combined activation in successive cycles, i.e., enhanced synchronized gamma and theta excitation mid-frontal theta-band activity as well as gates memory retrieval and also the functional connectivity (Carter et al., 1998; storage of new entries. van Driel et al., 2015). From the point of view 6. With priors specified as coherent of the Ouroboros Model, it is expected that schemata and posteriors resulting from the announcing a conflict trial leads to enhanced inclusion of actual activity, a Bayesian activity of the proposed consistency curation interpretation of the input and also choice stage, i.e., the anterior cingulate cortex. of action is achieved; interpretation- as Recent results provide strong evidence that well as prediction-errors are minimized. the dorsal anterior cingulate cortex drives

7. Repeating these actions in successive predictive coding accounts being able to iterative cycles with nested frequencies apply its explanation-pattern self reflectively will show up as oscillatory activations in a also to interoceptive inference (Seth, 2015). healthy brain. Consistency curation and discrepancy minimizing entails, first, consistency Emphasizing cognitive processing in checking, and, second, steering behavior such iterations as the Ouroboros Model does, some as to reduce short-term gaps and fundamental complication arises immediately: inconsistencies, as well as trying the best for when cutting a full circle open in twain to avoiding already known problems in the obtain a linear succession of steps, it is future. Optimum for this control task, all possible to pick out quite different points as relevant aspects concerning the environment, beginnings or ends, yielding in turn dissimilar the actor, her goals and motivations, perspectives and seemingly contradictory emotions, plans… are taken into account. interpretations, e.g., preparatory versus Comprehensive monitoring and directly monitoring activity as essential tasks of the employing its results for actual control are ACC. ―Earlier‖ and ―later‖, in a well-defined hypothesized to be implemented to a large sense, depends on the point of view. Still, extent in the ACC. fully respecting the progression of stages in Work on the Ouroboros Model in general and time, no problem with circularity arises. also on the role of the cingulate cortex is in The added value of the Ouroboros Model progress. Following a fundamental self- compared to other conceptualizations reflective and self-consistent approach, a first mentioned above lies in cross disciplinary coarse but overarching schematic sketch (like integration: starting with very simple and few theta biasing from the ACC) has to be filled- ingredients, i.e., memory compartmentalized in with more fine-grained and quantitative in schemata and a self-referential incremental details in subsequent iterations (like more control process, it appears possible to explain local gamma oscillations); collaborations to very diverse finding in many widely different this end are most welcome. Implementations fields in a common framework. Concerning in soft- and hard-ware would then be the next neural computing, promising directions (as a step harnessing the results for neural inspired first step, for future modelling efforts) are computing and for general intelligence of highlighted. artificial agents. On top of this come medical Prediction error minimization is essential for aspects; a deepened functional understanding the survival of living beings, and also very of a central hub in the human brain will important for artificial agents. The Ouroboros almost certainly open new perspectives and Model offers a principled account for very enable novel ways for the successful diverse activities based on bootstrapping from treatment of associated ailments simple associations and a very general process of discrepancy-use and future Acknowledgements avoidance. It can be seen as a "globalized" Very helpful initial guidance in structuring version of predictive coding with a strong and spotting relevant literature from diverse emphasis on iterative and self-steered articles in wikipedia and psychiopedia progressing of behavior implementing (http://www.psychit.com.au/Psychlopedia/arti Bayesian optimization, applicable to whatever cle.asp?id=1) is gratefully acknowledged. type of content. No real fundamental This work was funded privately by the author. distinction exists between sensory percepts or There are no data (yet) in addition to the memory representations, including ones of the references. agent herself. Also in this sense, the Ouroboros Model is akin to standard

References 1. Alexander WH, Brown JW. Medial and Cognitive Control. Psychological prefrontal cortex as an action-outcome Review 2001;108:624–652. predictor. Nature Neuroscience 11. Braem S, King JA, Korb FM, Krebs RM, 2011;14:1338–1344. Notebaert S, Egner T. The Role of 2. Allen M, Fardo F, Dietz M, Hillebrandt H, Anterior Cingulate Cortex in the Affective Friston KJ, Rees G, Roepstorff, A. Evaluation of Conflict. Journal of Anterior insula coordinates hierarchical Cognitive Neuroscience 2016;29:137–149. processing of tactile mismatch responses. 12. Braga RM, Buckner TL. Parallel NeuroImage 2016;127:34–43. Interdigitated Distributed Networks within 3. Allen M, Frank D, Schwarzkopf DS, Fardo the Individual Estimated by Intrinsic F, Winston JS, Hauser TU, Rees G. Functional Connectivity. Neuron Unexpected arousal modulates the 2017;95:457–471. influence of sensory noise on confidence. 13. Brown R, Kulik J. Flashbulb memories. eLife 2016:5:e18103. Cognition 1977;5: 73–99. 4. Allman JM, Hakeem A, Erwin JM, 14. Brunce JG, Zikopoulos B, Feinberg M, Nimchinsky E, Hof P. The Anterior Barbas H. Parallel Prefrontal Pathways Cortex, The Evolution of an Interface Reach Distinct Excitatory and Inhibitory between Emotion and Cognition. Ann. NY Systems in Memory-Related Rhinal Acad. Sci. 2001;935:107–117. Cortices. The Journal of Comparative 5. Asada H, Fukuda Y, Tsunoda S, Neurology 2013;521:4260–4283. Yamaguchi M, Tonoike M. Frontal 15. Bush G, Luu P, Posner MI. Cognitive and midline theta rhythms reflect alternate emotional influences in anterior cingulate activation of prefrontal cortex and anterior cortex. Trends in Cognitive Science cingulate cortex in humans. Neuroscience 2000;4:215–222. Letters 1999;274:29–31. 16. Carhart-Harris RL, Leech P, Hellyer PJ, 6. Barbas H. General Cortical and Special Shanahan M, Feilding A, Tagliazucchi E, Prefrontal Connections: Principles from Chialvo DR, Nutt D. The entropic brain: a Structure to Function. Ann. Rev. Neurosci. theory of conscious states informed by 2015;38:269–289. neuroimaging research with psychedelic 7. Bayne T, Hohwy J. Consciousness: drugs. Frontiers in Human Neuroscience Theoretical Approaches. In A.E. Cavanna 2014;8:1–22. et al. (eds.), Neuroimaging of 17. Carter CS, Braver TS, Barch DM, Consciousness, p. 23-35. Springer-Verlag Botvinick MM, Noll D, Cohen JD. Berlin, Heidelberg, 2013. Anterior cingulate cortex, error detection, 8. Berridge KC, Kringelbach ML. Pleasure and the online monitoring of performance. systems in the brain. Neuron 2015;86:646– Science 1998;280:747–749. 664. 18. Castellanos FX, Margulies DS, Kelly C, 9. Boldt A, Yeung N. Shared Neural Markers Uddin LQ, Ghaffari M, Kirsch A, Shaw D, of Decision Confidence and Error Shezad Z, Di Marino A, Biswal B. Detection, The Journal of Neuroscience Sonuga-Barke JS, Rotrosen J, Adler LA, 2015;35:3478–3484. Milham MP. Cingulate-Precuneus 10. Botvinick MM, Carter CS, Braver TS, Interactions: A New Locus of Dysfunction Barch DM, Cohen JD. Conflict Monitoring in Adult Attention-Deficit/Hyperactivity

Disorder. Biol. Psychiatry 2008;63:332– 29. Etkin A, Egner T, Kalisch R. Emotional 337. processing in anterior cingulate and medial 19. Cavanagh JF, Frank MJ. Frontal theta as a prefrontal cortex. Trends in Cognitive mechanism for cognitive control. Trends in Sciences 2011;15:85–93. Cognitive Science 2014;18:414–412. 30. Falkenstein M, Hohnsbein J, Hoormann J, 20. Cavanna AE. The precuneus and Blanke L. Effects of errors in choice consciousness. CNS Spectrums reaction tasks on the ERP under forced 2007;12:545–552. focused and divided attention. In: Brunia, 21. Charles L, van Opsta F, Marti S, Dehaene C.H.M. Galliard, A.W.K., Kok, A. (eds), S. Distinct brain mechanisms for conscious Psychological Brain Research. Tilburg versus subliminal error detection. NL, Tilburg University Press, 1990. NeuroImage 2013;73:80–94. 31. Ferdinand NK, Mecklinger A, Kray J, 22. Chaudhuri R, Knoblauch K, Gariel M-A, Gehring W. The Processing of Unexpected Kennedy H, Wandg X-J. A Large-Scale Positive Response Outcome in the Circuit Mechanism for Hierarchical Mediofrontal Cortex. The Journal of Dynamical Processing in the Primate Neuroscience 2012;23:12087–12092. Cortex. Neuron 2015;88:1–13. 32. Festinger L. A Theory of Cognitive 23. Ciompi L, Panksepp J. Energetic effects of Dissonance. California, Stanford emotions on cognitions - complementary University Press, 1957. psychological and psychosocial findings. 33. Friston K. The free-energy principle: a In: Ellis, R. Newton, N. (eds.), unified brain theory? Nature Reviews Consciousness and Emotion, p. 23–25. J. Neuroscience 2010;11:127–38. Benjamins Publishing Company. 34. Froese T and Ikegami T. The brain is not Amsterdam-Philadelphia, 2005. an isolated "black box", nor is its goal to 24. Colgin LL. Theta-gamma coupling in the become one. Behavioral and Brain entorhinal-hippocampal system. Current Sciences 2013;36:33–34. Opinions in Neurobiology 2015;31:45–50. 35. Gajewski PD, Störig P, Falkenstein M. 25. Compton RJ, Robinson MD, Ode S, ERP—Correlates of response selection in a Quandt LC, Fineman SL, Carp J. Error- response conflict paradigm. Brain monitoring ability predicts daily stress Research 2008;1189:127–134. regulation. Psychological Science 36. Garavan H, Ross TJ, Murphy K. Roche 2008;19:702–708. RAP, Stein, EA. Dissociable executive 26. Crottaz-Herbette S, Menon V. Where and functions in the dynamic control of When the Anterior Cingulate Cortex behavior: Inhibition, error detection, and Modulates Attentional Response: correction. NeuroImage, 2002;17:1820- Combined fMRI and ERP Evidence. 1829. Journal of Cognitive Neuroscience 37. Gehring WJ, Goss B, Coles MGH, Meyer 2006;18:766–780. DE, Donchin E. A neural system for error 27. Del Cul A, Dehaene S, Reyes P, Bravo E, detection and compensation. Psychological Slachevsky A. Causal role of prefrontal Science 1993;4:385–390. cortex in the threshold for access to 38. Gmeindl L, Chiu YC, Esterman MS, consciousness. Brain;2009:132;2531– Greenberg AS, Courtney SM, Yantis S. 2540. Tracking the will to attend: Cortical 28. Domenech P, Dreher J-C. Decision activity indexes self-generated, voluntary Threshold Modulation in the Human Brain. shifts of attention. Atten Percept The Journal of Neuroscience Psychophys. 2016;78:2176–2184. 2010;30:14305–14317. 39. Gray MC, König P, Engel AK, Singer W. Oscillatory responses in cat visual cortex

exhibit inter-columnar synchronization 50. Ide JS, Shenoy P, Yu AJ, Li CR. Bayesian which reflects global stimulus properties. Prediction and Evaluation in the Anterior Nature 1989;338:334–337. Cingulate Cortex. The Journal of 40. Grotheer M, Kovács G. Can predictive Neuroscience 2013,33:2039–2047. coding explain repetition suppression? 51. Jahn A, Nee DE, Alexander WH, Brown Cortex 2016;80:113–124. JW. Distinct regions of anterior cingulate 41. Hayden BY, Pearson JM, Platt ML. Fictive cortex signal prediction and outcome Reward Signals in the Anterior Cingulate evaluation, NeuroImage 2014;95: 80–89. Cortex. Science 2009;324:948–950. 52. Jepma M, Verdonschot RG, van 42. Herbet G, Lafargue G, de Chamfleur NM, Steenbergen H, Rombouts SA, Moritz-Gasser S, le Bars E, Bonnetblanc F, Nieuwenhuis S. Neural mechanisms Duffau H. Disrupting posterior cingulate underlying the induction and relief of connectivity disconnects consciousness perceptual curiosity. Front Behav. from the external environment. Neurosci. 2012;6:5. Published online 2012 Neuropsychologia 2014;56:239–244. Feb 13. doi: 10.3389/fnbeh.2012.00005. 43. Herrmann CS, Munk MHJ. Engel AK. 53. Jiang H, White MP, Greicius MD, Waelde Cognitive functions of gamma-band LC, David Spiegel D. Brain Activity and activity: memory match and utilization. Functional Connectivity Associated with Trends in Cognitive Sciences 2004;8:347– Hypnosis. Cerebral Cortex, 2016; 1–11. 355. Advance Access published July 28, 2016. 44. Holroyd CB, Dien J, Coles MGH. Error- 54. Joshi S, Li Y, Kalwani RM, Gold JI. related scalp potentials elicited by hand Relationships between Pupil Diameter and and foot movements: Evidence for an Neuronal Activity in the Locus Coeruleus, output-independent error-processing Colliculi, and Cingulate Cortex. Neuron system in humans. Neuroscience Letters 2016;89:221–234. 1998;242:65–68. 55. Kang YHR, Petzschner FH, Olpert DM, 45. Holroyd CB, Coles MGH. The neural Shadlen MN, Piercing od Consciousness as Basis of Human Error Processin: a threshold-Crossing Operation. Current Reinforcement Learning, Dopamine, and Biology 2017;27:1–11. the Error-Related Negativity. 56. Kim J, Wasserman E, Edward A, Castro L, Psychological Review 2002;109:679–709. Freeman JH. Anterior cingulate cortex 46. Holroyd CB, Nieuwenhuis S, Mars RB, inactivation impairs rodent visual selective Coles GH. In M. I. Posner (Ed.), Cognitive attention and prospective memory. Behav. neuroscience of attention. New York, Neurosci. 2016;130:75–90. Guilford Press, 2004. 57. Klein-Flügge MC, Kennerley SW, Friston 47. Holroyd CB, Yeung N. Motivation of K, Bestmann S. Neural Signatures of extended behaviors by anterior cingulate Value Comparison in Human Cingulate cortex. Trends in Cognitive Sciences Cortex during Decisions Requiring an 2012;16:122–128. Effort-Reward Trade-off. The Journal of 48. Hsee CK. The Pandora Effect, The power Neuroscience 2016;28:1002–1015. and Peril of Curiosity, Psychological 58. Kok P, Jehee JFM, de Lange FP. Less is Science, OnlineFirst, published on March More: Expectation Sharpens 21, 2016. Representations in the Primary Cortex. 49. Hsieh JC, Stone-Elander S, Ingvar M. Neuron 2012;75:265–270. Anticipatory coping of pain expressed in 59. Lisman JE, Idiart MAP. Storage of 7+/- the human anterior cingulate cortex: a Short-Term Memories in Oscillatory positron emission tomography study. Subcycles. Science 1995;267:1512–1515. Neuroscience Letters 1999;262:61–64.

60. Little DY, Sommer FT. Learning in Affective Neuroscience, 2016;11:1345– embodied action-perception loops through 1353. exploration. arXiv preprint 71. Moors A, Ellsworth PC, Scherer KR, arXiv:1112.1125. 2011 Dec 6. . Frijda NH. Appraisal Theories of Emotion: 61. Loewenstein G. The Psychology of State of the Art and Future Development. Curiosity: A Review and Reinterpretation. Emotion Review 2013;5:119–124. Psychological Bulletin 1994;116:75–98. 72. Morton BE. Behavioral laterality of the 62. Logiaco L, Quilodran R, Procyk E, Arleo brain: support for the binary construct of A. Spatiotemporal Spike Coding of hemisity. Frontiers in Psychology Behavioral Adaptation in the Dorsal 2013;4:1–12. Anterior Cingulate Cortex. PLOS Biology 73. Moser JS, Schroder HS, Heeter C, Moran April 12, 2015. TP, Lee YH. Mind Your Errors: Evidence 63. Luduena AG, Gros C. A Self-organized for a Neural Mechanism Linking Growth Neural Comparator. Neural Computation Mind-Set to Adaptive Posterior 2013;25:1006–1028. Adjustments. Psychological Science 64. Luu P, Pederson SM. The anterior 2011;22:1484–1489. cingulate cortex: Regulating actions in 74. Mulert C, Menzinger E, Leicht G, Pogarell context. In M. I. Posner (Ed.), Cognitive O, Hegerl U. Evidence for a close neuroscience of attention. New York, relationship between conscious effort and Guilford Press, 2004. anterior cingulate cortex activity. 65. Luu P, Tucker DM, Makeig S. Frontal International Journal of Psychophysiology midline Theta and the error-related 2005;56:65–80. negativity: neurophysiological mechanisms 75. Murtha S, Chertkow H, Beauregard M, of action regulation. Clinical Dixon R, Evans A. Anticipation Causes Neurophysiology 2004;115:1821–1835. Increased Blood Flow to the Anterior 66. Margulies DS, Kelly CAM, Uddin LQ, Cingulate Cortex. Human Brain Mapping Biswal BB, Casellanos FX, Milham MP. 1996;4:103-112. Mapping the functional connectivity of 76. Noyce A, Sekuler R. Violations of newly- anterior cingulate cortex. Neuroimage learned predictions elicit two distinct P3 2007;37:579–788. components. Frontiers in Human 67. Maryott J, Noyce A, Sekuler R. Eye Neuroscience 2014;8:preceeding p.1. movements and imitation learning: 77. Nyhus E and Curran T. Functional role of Intentional disruption of expectation. gamma and theta oscillations in episodic Journal of Vision 2011;11:1–16. memory. Neuroscience and Biobehavioral 68. Matsunaga M, Kawamichi H, Koike T, Reviews 2010;34:1023–1035. Yoshihara K, Yoshida Y, Takahashi HK, 78. Öngür D, Price JL. The organization of Nakagawa E, Sadato N. Structural and networks within the orbital and medial functional associations of the rostral prefrontal cortex of rats, monkeys and anterior cingulated cortex with subjective humans. Cerebral Cortex 2000;10:206– happiness. Neuroimage 2016;134:132– 219. 141. 79. Parkinson JA, Willoughby PJ, Robbins 69. Miller KD. Canonical computations of TW, Everitt BJ. Disconnection of the cerebral cortex. Current Opinion in anterior cingulate cortex and nucleus Neurobiology 2016;37:75–84. accumbens core impairs Pavlovian 70. Mischkowski D, Crocker J, Way BM. approach behavior: Further evidence for From painkiller to empathy killer: limbic cortical–ventral striatopallidal acetaminophen (paracetamol) reduces systems. Behavioral Neuroscience empathy for pain. Social Cognitive and 2000;114:42–63.

80. Paus T. Primate Anterior Cingulate Cortex: Attention. Midas Online 2015, Where Motor Control, Drive and http://mindsonline.philosophyofbrains.com Cognition Interface. Neuroscience /2015/session4/three-problems-for-the- 2001;2:417–424. predictive-coding-theory-of-attention/, 81. Phillips JM, Vink M, Everling S, downloaded 20 November 2016. Womelsdorf T. A Long-Range Fronto- 89. Ridderinkhof KA, van den Wildenberg Parietal 5- to 10-Hz Network Predicts WPM, Segalowitz SJ, Carter CS. "Top-Down" Controlled Guidance in a Neurocognitive mechanisms of cognitive Task-Switching Paradigm. Cerebral control: The role of prefrontal cortex in Cortex 2014;24:1996–2008. action selection, response inhibition, 82. Pourtois G, Vocat R, N‘Diaye K, Spinelli performance monitoring, and reward-based L, Seeck M, Vuilleumier P. Errors recruit learning. Brain and Cognition cognitive and emotional monitoring 2004;56:129–140. systems: Simultaneous intracranial 90. Robinson, MD. Gassing, braking, and self- recording in the dorsal anterior Cingulate regulating: Error self-regulation, well- gyrus and amygdala combined with fMRI. being, and goal-related processes. Journal Neuropsychologia 2010;48:1144–1159. of Experimental Social Psychology 83. Proulx T, Inzlicht M, Harmon-Jones E. 2007;43:1–16. Understanding all inconsistency 91. Sauseng P, Griesmayr B, Freunberger R, compensation as a palliative response to Klimesch W. Control mechanisms in violated expectations. Trends in Cognitive working memory: A possible function for Sciences 2012;16:285–291. EEG theta oscillations. Neuroscience and 84. Qin P, Di H, Liu Y, Yu S, G Q, Duncan N, Biobehavioral Reviews 2010;34:1015– Weng X, Laureys S, Northoff G. Anterior 1022. Cingulate Activity and the Self in 92. Sauseng P, Conci M, Wild B, Geyer T. Disorders of Consciousness. Human Brain Predictive coding in visual search as Mapping 2010;31:1993–2002. revealed by cross-frequency EEG phase 85. Railo H, Revonsuo A, Koivisto M. synchronization. Frontiers in Psychology Behavioral and electrophysiological 2015;6:1655. evidence for fast emergence of visual 93. Scheibe C, Schubert R, Sommer W, consciousness. Neuroscience of Heekeren HR. Electrophysiological Consciousness 2015:1–12, doi: evidence for the effect of prior probability 10.1093/nc/niv004. on response preparation. 86. Rajasethupathy P, Sankaran S, Marshel JH, Psychophysiology 2009;46:748–770. Kim CK, Ferenczi E, Lee SY, Berdt A, 94. Schouppe N, Braem S, De Houwer J, Ramakrishnan C, Jaffe A, Lo M, Liston C, Silvetti M, Verguts T, Ridderinkhof KA, Deisseroth K. Projections from the Notebaert W. No pain, no gain: the neocortex mediate top-down control of affective valence of congruency conditions memory retrieval. Nature 2015;526:653– changes following a successful response. 659. Cognitive, affective & behavioral 87. Randles D, Kam JWY, Heine SJ, Inzlicht neuroscience 2015;15:251–261. M, Handy, TC. Acetaminophen attenuates 95. Schwarz N, Clore GL. Mood, error evaluation in cortex. Social Cognitive misattribution, and judgments of well- and Affective Neuroscience Advances, being: Informative and directive functions Advance Access published March 17, of affective states. Journal of Personality 2016. and Social Psychology 1983;45:513–523. 88. Ransom M, Fazelpour S. Three Problems 96. Selz O, Über die Gesetze des geordneten for the Predictive Coding Theory of Denkverlaufs, ersterTeil. Spemann, 1913.

97. Sergent C, Dehaene S. Is Consciousness a LSD-Induced Ego Dissolution. Current Gradual Phenomenon? Evidence for an Biology 2016;26:1–8. All-or-None Bifurcation During the 106. Thomsen K. The Ouroboros Model in Attentional Blink. Psychological Science the light of venerable criteria, 2004;15:720–728. Neurocomputing 2010;74:121–128. 98. Seth AK. The Cybernetic Bayesian Brain – 107. Thomsen K. The Ouroboros Model, From Interoceptive Inference to Selected Facets. In: Hernández, C. et al. Sensorimotor Contingencies. In: (eds.) From Brains to Systems, New York, Metzinger, T & Windt, M (eds.) Open Dordrecht, Heidelberg, London, Springer, MIND 2015;35:1–24. 2011. 99. Shackman AJ, Salomons TV, Slagter HA, 108. Thomsen, K. Consciousness for the Fox AS, Winter JJ, Davidson RJ. The Ouroboros Model, Journal for Machine Integration of Negative Affect, Pain, and Consciousness 2011;3,163–175. Cognitive Control in the Cingulate Cortex. 109. Thomsen K. The Cerebellum according Nature Reviews Neuroscience to the Ouroboros Model, the 'Interpolator 2011;12:154–167. Hypothesis', Journal of Communication 100. Shen C, Ardid S, Kaping D, and Computer 2014;11:239–254. Westendorff S, Everling S, Womelsdorf T. 110. Thomsen K. The Ouroboros Model Anterior Cingulate Cortex Cells Identify embraces its sensory-motoric foundations. Process-Specific Errors of Attentional Studies in Logic, Grammar and Rhetoric Control Prior to Transient Prefrontal- 2015;41:105–125. Cingulate Inhibition. Cerebral Cortex 111. Thomsen K. The Hippocampus 2015;25:2213–2228. According to the Ouroboros Model, the 101. Shenhav A, Botvinick MM, Cohen JD. 'Expanding Memory Index Hypothesis', The Expected Value of Control: An IARIA COGNITIVE conference, Athens integrative Theory of Anterior Cingulate 19-23 February, 2017. Cortex Function. Neuron 2013;79:217– 112. Todorovic A, Schoffelen J-M, van Ede 240. F, Maris E, de Lange FP. Temporal 102. Spratling MW. Reconciling predictive Expectation and Attention Jointly coding and biased competition models of Modulate Auditory Oscillatory Activity in cortical function. Frontiers in the Beta Band. PLOS ONE, March 23, Computational Neuroscience 2008;2:1–8. 2015. 103. Spratling MW. Predictive coding as a 113. Van Noordt SJR, Desjardins JA, model of biased competition in visual Segalowitz SJ. Watch out! Medial frontal attention. Vision Research 2008;48:1391– cortex is activated by cues signaling 1408. potential changes in response demands. 104. Subramaniam K, Kounios J, Parrish NeuroImage 2015;114:356–370. TB, Jung-Beeman M. A Brain mechanism 114. Van Veen V, Krug MK, Schooler JW, for Facilitation of Insight by Positive Carter CS. Neural activity predicts attitude Affect. Journal of Cognitive Neuroscience change in cognitive dissonance. Nature 2008;21:415–432. Neuroscience 2009;12:1469–1474. 105. Tagliazuocchi E, Roseman L, Kaelen 115. Van den Heuvel MP, Sporns O. M, Orban C, Muthukumaraswamy SD, Network hubs in the human brain, Trends Murphy K, Laufs H, Leech R, McGonigle in Cognitive Science 2013;17,683–696. J, Crossley N, Bullmore E, Williams T, 116. Van Driel J, Swart JC, Egner T, Bolstridge M, Feilding A, Nutt DJ, Ridderinkhof KR, Cohen MX. (no) time Carhart-Harris R. Increased Global for control: Frontal theta dynamics reveal Functional Connectivity Correlates with the cost of temporally guided conflict

anticipation. Cognitive, affective & obsession, and the psychology of mental behavioral neuroscience 2015;15:787– control. London: The Guilford Press, 1989. 807. 122. Wegner DM, Wenzlaff RM, Kozak M. 117. Voloh B, Valiante TA, Everling S, The return of suppressed thoughts in Womelsdorf T. Theta-gamma coordination dreams. Psychological Science between anterior cingulate and prefrontal 2004;15:232–236. cortex indexes correct attention shifts. 123. Wessel JR, Jenkonson N, Brittain J-S, Proceedings of the National Academy of Voegts S, Aziz TZ, Aron AR. Surprise Sciences 2015;112: 8457–8602. disrupts cognition via a front-basal ganglia 118. Walton ME, Mars RB. Probing human suppressive mechanism. Nature and monkey anterior cingulate cortex in Communications 2015;7:11195 variable environments. Cognitive, 124. Zaki J, Wager TD, Singer T, Keysers Affective, & Behavioral Neuroscience C, Gazzola V. The Anatomy of Suffering: 2007;7:413–422. Understanding the Relationship between 119. Watson KK, Jones TK, Allman, JM. Nociceptive and Empathic Pain. Trends in Dentritic Architecture of the Von Cognitive Sciences 2016;20:249–259 Economo Neurons. Neuroscience 125. Zarr N, Brown JW. Hierarchical error 2006;141:1107–1112. representation in medial prefrontal cortex. 120. Watson KK, Matthews Bj, Allman, JM. Neuroimage 2016;124:238–247. Brain Activation during Sight Gags and 126. Zhang H, Fell J, Staresina BP, Weber Language-Dependent Humor. Cerebral B, Einer CE, Axmacher N. Gamma Power Cortex 2007;17:314–324. Reductions Accompany Stimulus-Specific 121. Wegner DM. White bears and other Representations of Dynamic Events. unwanted thoughts: Suppression, Current Biology 2016;25:635–640.