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Cephalopods and the Evolution of the Mind
Cephalopods and the Evolution of the Mind Peter Godfrey-Smith The Graduate Center City University of New York Pacific Conservation Biology 19 (2013): 4-9. In thinking about the nature of the mind and its evolutionary history, cephalopods – especially octopuses, cuttlefish, and squid – have a special importance. These animals are an independent experiment in the evolution of large and complex nervous systems – in the biological machinery of the mind. They evolved this machinery on a historical lineage distant from our own. Where their minds differ from ours, they show us another way of being a sentient organism. Where we are similar, this is due to the convergence of distinct evolutionary paths. I introduced the topic just now as 'the mind.' This is a contentious term to use. What is it to have a mind? One option is that we are looking for something close to what humans have –– something like reflective and conscious thought. This sets a high bar for having a mind. Another possible view is that whenever organisms adapt to their circumstances in real time by adjusting their behavior, taking in information and acting in response to it, there is some degree of mentality or intelligence there. To say this sets a low bar. It is best not to set bars in either place. Roughly speaking, we are dealing with a matter of degree, though 'degree' is not quite the right term either. The evolution of a mind is the acquisition of a tool-kit for the control of behavior. The tool-kit includes some kind of perception, though different animals have very different ways of taking in information from the world. -
The Three Neurogenetic Phases of Human Consciousness: the Possibility of Transhuman and Posthuman Consciousness
International Journal of Arts & Sciences, CD-ROM. ISSN: 1944-6934 :: 07(02):381–394 (2014) Copyright c 2014 by UniversityPublications.net THE THREE NEUROGENETIC PHASES OF HUMAN CONSCIOUSNESS: THE POSSIBILITY OF TRANSHUMAN AND POSTHUMAN CONSCIOUSNESS John K. Grandy In previous works, the first neurogenetic account of human consciousness has been established and was delineated into three distinct phases- the emergence of neuron-based consciousness, the continuum of neuron-based consciousness, and neurodegeneration [1, 2].In this model, DNA consciousness gives rise to human consciousness in the form of neurogenetic correlates of consciousness (NgCC) and then the NgCC underlying the neurons provide continuous activity during the conscious experience. This engenders a continuum of neuron-based consciousness working in tandem with a neurogenetic substructure. Unfortunately, later in life the neurons wear down and modalities of human consciousness are decreased or lost [3]. This loss can proceed in an age-related fashion as seen in mild cognitive impairment or this process can have a genetic component as seen in Alzheimer disease (AD). Currently, genetic experiments are underway to reverse some of the symptoms of AD, e.g., the FGF-2 gene transfer for memory improvement in mice with AD [4]. However, in the future can this, or similar, genetic therapies be used to enhance human consciousness in patients without AD? Would this be the first steps into posthuman consciousness? In 2009, it was proposed and supported that genetic engineering technology may provide the opportunity for a selected genetic destination [5] .This would make it possible to select a phenotype or genetic endpoint and make it possible in any organism including humans. -
A Theory of Consciousness: Computation, Algorithm, and Neurobiological Realization
Preprint (version 20 June 2019) A theory of consciousness: computation, algorithm, and neurobiological realization J. H. van Hateren Johann Bernoulli Institute for Mathematics and Computer Science, University of Groningen, The Netherlands; [email protected] Abstract The most enigmatic aspect of consciousness is the fact that it is felt, as a subjective sensation. The theory proposed here aims to explain this particular aspect. The theory encompasses both the computation that is presumably involved and the way in which that computation may be realized in the brain’s neurobiology. It is assumed that the brain makes an internal estimate of an individual’s own evolutionary fitness, which can be shown to produce a special, distinct form of causation. Communicating components of the fitness estimate (either for external or internal use) requires inverting them. Such inversion can be performed by the thalamocortical feedback loop in the mammalian brain, if that loop is operating in a switched, dual-stage mode. A first (nonconscious) stage produces forward estimates, whereas the second (conscious) stage inverts those estimates. It is argued that inversion produces another special, distinct form of causation, which is spatially localized and is plausibly sensed as the feeling of consciousness. Keywords Consciousness · Sentience · Evolution · Fitness · Estimation · Thalamocortical 1 Introduction The terms ‘consciousness’ and ‘conscious’ have various meanings. They may refer to the state of being awake (as in ‘regaining consciousness’), the process of gaining access to certain facts as they affect the senses or are retrieved from memory (as in ‘becoming conscious of something’), and the subjective sensation associated with experiencing (e.g., when feeling pain or joy, and when undergoing a visual experience). -
Theoretical Models of Consciousness: a Scoping Review
brain sciences Review Theoretical Models of Consciousness: A Scoping Review Davide Sattin 1,2,*, Francesca Giulia Magnani 1, Laura Bartesaghi 1, Milena Caputo 1, Andrea Veronica Fittipaldo 3, Martina Cacciatore 1, Mario Picozzi 4 and Matilde Leonardi 1 1 Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; [email protected] (F.G.M.); [email protected] (L.B.); [email protected] (M.C.); [email protected] (M.C.); [email protected] (M.L.) 2 Experimental Medicine and Medical Humanities-PhD Program, Biotechnology and Life Sciences Department and Center for Clinical Ethics, Insubria University, 21100 Varese, Italy 3 Oncology Department, Mario Negri Institute for Pharmacological Research IRCCS, 20156 Milan, Italy; veronicaandrea.fi[email protected] 4 Center for Clinical Ethics, Biotechnology and Life Sciences Department, Insubria University, 21100 Varese, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-02-2394-2709 Abstract: The amount of knowledge on human consciousness has created a multitude of viewpoints and it is difficult to compare and synthesize all the recent scientific perspectives. Indeed, there are many definitions of consciousness and multiple approaches to study the neural correlates of consciousness (NCC). Therefore, the main aim of this article is to collect data on the various theories of consciousness published between 2007–2017 and to synthesize them to provide a general overview of this topic. To describe each theory, we developed a thematic grid called the dimensional model, which qualitatively and quantitatively analyzes how each article, related to one specific theory, debates/analyzes a specific issue. -
The Human Thalamus Is an Integrative Hub for Functional Brain Networks
5594 • The Journal of Neuroscience, June 7, 2017 • 37(23):5594–5607 Behavioral/Cognitive The Human Thalamus Is an Integrative Hub for Functional Brain Networks X Kai Hwang, Maxwell A. Bertolero, XWilliam B. Liu, and XMark D’Esposito Helen Wills Neuroscience Institute and Department of Psychology, University of California, Berkeley, Berkeley, California 94720 The thalamus is globally connected with distributed cortical regions, yet the functional significance of this extensive thalamocortical connectivityremainslargelyunknown.Byperforminggraph-theoreticanalysesonthalamocorticalfunctionalconnectivitydatacollected from human participants, we found that most thalamic subdivisions display network properties that are capable of integrating multi- modal information across diverse cortical functional networks. From a meta-analysis of a large dataset of functional brain-imaging experiments, we further found that the thalamus is involved in multiple cognitive functions. Finally, we found that focal thalamic lesions in humans have widespread distal effects, disrupting the modular organization of cortical functional networks. This converging evidence suggests that the human thalamus is a critical hub region that could integrate diverse information being processed throughout the cerebral cortex as well as maintain the modular structure of cortical functional networks. Key words: brain networks; diaschisis; functional connectivity; graph theory; thalamus Significance Statement The thalamus is traditionally viewed as a passive relay station of information from sensory organs or subcortical structures to the cortex. However, the thalamus has extensive connections with the entire cerebral cortex, which can also serve to integrate infor- mation processing between cortical regions. In this study, we demonstrate that multiple thalamic subdivisions display network properties that are capable of integrating information across multiple functional brain networks. Moreover, the thalamus is engaged by tasks requiring multiple cognitive functions. -
The Thalamus
212 Neuroanatomy Reflection Corner The Thalamus Sagar Karia1 1Specialty Medical Officer, Department of Psychiatry, Lokmanya Tilak Municipal Medical College, Mumbai. E-mail – [email protected] INTRODUCTION Word Thalamus from Greek origin meaning “inner room” or “chamber”. Is an egg shaped mass of grey matter forming part of Diencephalon and forming lateral wall of 3rd ventricle. Narrow anterior end is directed medially while broad posterior end is directed laterally. Its long axis is 300 oblique to midline. Size is 3.5cm x 1.5cm. Covering its lateral surface is the external medullary lamina consisting of thalamocortical and corticothalamic fibres. Internal medullary lamina consists mainly of internuclear thalamic connections. It is 'Y' shaped and divides thalamus into 3 different nuclear masses. Thalamic Nuclei Anterior Group: portion between diverse limbs of 'Y'. It contains Anterior nuclei. Medial Group: part of thalamus lying on medial side of stem of 'Y'. It contains intralaminar nuclei, centromedian nuclei, medial nuclei and midline nuclei. Lateral Group: part lying on lateral side of stem of 'Y'. It is divided into 2 groups- ventral group and dorsal group. Ventral group contains ventroanterior, venterolateral, and venteroposterior nuclei and most posteriorly medial and lateral geniculate bodies. Venteroposterior nuclei is divided into venteroposteriorlateral and venteroposteriormedial nuclei. Dorsal group contains pulvinar, lateral posterior and lateral dorsal nuclei. Indian Journal of Mental Health 2015; 2(2) 213 Connections of the Thalamus Functionally divided into extrinsic and intrinsic nuclei. Extrinsic nuclei are cortical relay nuclei and receive afferent fibres from extrathalamic sources. Axons of these cells are distributed to primary cortical areas- pre and post central cortices, visual and auditory cortical areas. -
The Primate Pulvinar Nuclei: Vision and Action
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Repositorio da Universidade da Coruña Trends in Neurosciences, vol. 23, issue 1: 35-39 The primate pulvinar nuclei: vision and action Kenneth L. Grieve, Carlos Acuña and Javier Cudeiro Abstract The pulvinar nuclei of the thalamus are proportionately larger in higher mammals, particularly in primates, and account for a quarter of the total mass. Traditionally, these nuclei have been divided into oral (somatosensory), superior and inferior (both visual) and medial (visual, multi-sensory) divisions. With reciprocal connections to vast areas of cerebral cortex, and input from the colliculus and retina, they occupy an analogous position in the extra- striate visual system to the lateral geniculate nucleus in the primary visual pathway, but deal with higher-order visual and visuomotor transduction. With a renewed recent interest in this thalamic nuclear collection, and growth in our knowledge of the cortex with which it communicates, perhaps the time is right to look to new dimensions in the pulvinar code. Keywords: Primate; Pulvinar; Reference frame; Salience; Cortico-thalamic; Spatial attention The pulvinar nuclei of the thalamus lie posterior, medial and dorsal to their much better known cousin, the lateral geniculate nucleus, and ‘cover’ the underlying superior colliculus (SC). In the same way as the lateral geniculate (‘knee-like’) nucleus curves around the rising optic tract, the pulvinar (‘cushion’) forms a larger and more-diffuse, but recognizable, mass around the axonal tract that arises from the SC, the brachium of the SC (see Fig. 1). The original four nuclei of the macaque pulvinar were defined in early studies on purely anatomical grounds1 and 2. -
Files/2014 Women and the Big Picture Report.Pdf>, Accessed 6 September 2018
The neuroscientific uncanny: a filmic investigation of twenty-first century hauntology GENT, Susannah <http://orcid.org/0000-0003-0091-2555> Available from the Sheffield Hallam University Research Archive (SHURA) at: http://shura.shu.ac.uk/26099/ A Sheffield Hallam University thesis This thesis is protected by copyright which belongs to the author. The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author. When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given. Please visit http://shura.shu.ac.uk/26099/ and http://shura.shu.ac.uk/information.html for further details about copyright and re-use permissions. THE NEUROSCIENTIFIC UNCANNY: A FILMIC INVESTIGATION OF TWENTY-FIRST CENTURY HAUNTOLOGY Susannah Gent A thesis submitted in partial fulfilment of the requirements of Sheffield Hallam University for the degree of Doctor of Philosophy October 2019 Candidate Declaration I hereby declare that: 1. I have not been enrolled for another award of the University, or other academic or professional organisation, whilst undertaking my research degree. 2. None of the material contained in the thesis has been used in any other submission for an academic award. 3. I am aware of and understand the University’s policy on plagiarism and certify that this thesis is my own work. The use of all published or other sources of material consulted have been properly and fully acknowledged. 4. The work undertaken towards the thesis has been conducted in accordance with the SHU Principles of Integrity in Research and the SHU Research Ethics Policy. -
Page 1 85 Split Decisions GEORGE WOLFORD, MICHAEL B. MILLER
B5 SpHtDecisions GEORGE \VOLFORD) N,IICII{EL B. NIILLER, AND \IICFL.\EL S. GAZZAT\IGA .\B: rR.\, r ::ril-irlain patients provide a lascinating look at some The split-brainoperation ,,;' tir, r..,:,. .irrr,trncling consciousness.lVe bricfl1' rL-viewpirst lin,i:ir..l-.,:r,: r:r..rghrsgained lrom studying thcsc patients. l\:€ Split-brain surgery is a treatment for certain tvpes o1' ill:( i.:. ::. r-.,,r,'cictail some of thc more irrteresting(ar us) findines intractable epilepsri Seizures in epilepsv are causecl bl.an .irr., 'lr.' ..,': cclition of this volurne. \\r conclude bl ruqgestinge abnormal electrical discharge that leads to a reverberating rrrr'r:ifltcL rer-sion of signal cletectiontheorv that mav shed some ii{l;r ,,rr aspcctsof consciousnessir thcse paticnts. or rhvthmic dischzrrge.In some individuals, the rhrthmic dis- charges recruit tissr,rein both l-remispheres.The split surgerv ( ' .,lri//d-rJin tlrcsplit brain involves severing all or part of the corpus callosum. the m:rjor fiber tract connectine the tr,r'or:erebral hen-risphercs, ,irr n:rtient. nll- I .._.-^ r*,-_^--_ _--e.f a Llnlqlle perspecuve on some and on occasion other {brcbrain commisures as rvell. The ': .- l{ conscious experienc:e.and pcrhaps on the nature corpus callosum is the largcst fiber tract in the brain. f'he ri.ciousness itself. Rogel Sperr',' once relerred to the human corpus callosum contains about 200 million axoris. "tu,o : ,\ separate realms o1' conscious a$'areness;t\'vo originating lrom layer 2/3 pyranriclal ncurons (r\boitiz et al.. :r:.- -. perceiving, thinkine arrd rernernbcring systtms." 1992). -
Magnetic Resonance Imaging of Mediodorsal, Pulvinar, and Centromedian Nuclei of the Thalamus in Patients with Schizophrenia
ORIGINAL ARTICLE Magnetic Resonance Imaging of Mediodorsal, Pulvinar, and Centromedian Nuclei of the Thalamus in Patients With Schizophrenia Eileen M. Kemether, MD; Monte S. Buchsbaum, MD; William Byne, MD, PhD; Erin A. Hazlett, PhD; Mehmet Haznedar, MD; Adam M. Brickman, MPhil; Jimcy Platholi, MA; Rachel Bloom Background: Postmortem and magnetic resonance im- reduced in all 3 nuclei; differences in relative reduction aging (MRI) data have suggested volume reductions in did not differ among the nuclei. The remainder of the the mediodorsal (MDN) and pulvinar nuclei (PUL) of the thalamic volume (whole thalamus minus the volume of thalamus. The centromedian nucleus (CMN), impor- the 3 delineated nuclei) was not different between schizo- tant in attention and arousal, has not been previously stud- phrenic patients and controls, indicating that the vol- ied with MRI. ume reduction was specific to these nuclei. Volume rela- tive to brain size was reduced in all 3 nuclei and remained Methods: A sample of 41 patients with schizophrenia significant when only patients who had never been ex- (32 men and 9 women) and 60 healthy volunteers (45 posed to neuroleptic medication (n=15) were consid- men and 15 women) underwent assessment with high- ered. For the MDN, women had larger relative volumes resolution 1.2-mm thick anatomical MRI. Images were than men among controls, but men had larger volumes differentiated to enhance the edges and outline of the than women among schizophrenic patients. whole thalamus, and the MDN, PUL, and CMN were out- lined on all slices by a tracer masked to diagnostic Conclusions: Three association regions of the thala- status. -
Neurobiological Theories of Consciousness. In
CONS: 00055 a0005 Neurobiological Theories of Consciousness S Kouider, Laboratoire des Sciences Cognitives et Psycholinguistique, CNRS/EHESS/ENS-DEC, Paris, France ã 2009 Elsevier Inc. All rights reserved. Cognitive Influences on Neurobiological Glossary s0010 Accounts g0005 Neural correlates of consciousness –They p0010 are defined by Christoph Koch as ‘‘The Regarding the influence of cognitive theories, minimal set of neuronal mechanisms or the majority of neurobiological accounts can be events jointly sufficient for a specific seen, in fact, as extensions of preexisting cognitive conscious percept or experience.’’ They theories (e.g., for instance global workspace the- allow to avoid the difficult problem of directly ories). Indeed, one of the main tasks exercised by looking for neural bases. neurobiologists in the last two decades has been to search for cerebral or neuronal equivalents to the g0010 Panpsychism – Reflects the philosophical functional elements constituting cognitive models doctrine that everything (in Greek, ‘pan’) has PROOF a mind (‘psyche’) and is therefore conscious. (e.g., the dorsolateral prefrontal cortex for volun- Some theories presented in this article tary control, or long range axons for connecting endorse a certain form of panpsychism in brain regions associated with ‘unconscious’ and which anything that transmits information is ‘conscious’ processing). Of course, many neuro- in a way conscious. biologists disagree with this approach. Conscious- ness, because it is a biological problem, should be g0015 The hard problem – It is the problem of explaining how and why we have the reframed the other way around, by focusing pri- subjective experience of consciousness. It is marily on its structural basis rather than relying on often contrasted with the easy problem, cognitive theories, often considered too specula- which consists of describing consciousness tive. -
The Psychophysics of Consciousness: a Hypothesis
S.R. Joye The Psychophysics of Consciousness The Psychophysics of Consciousness: A Hypothesis "Hypothesis: a very poor choice of word to designate the supreme spiritual act by which the dust-cloud of experience takes on form and is kindled at the fire of knowledge." Pierre Teilhard de Chardin August 9, 2013 S.R. Joye, B.S. Electrical Engineering, M.A. Asian Philosophy, CIIS Doctoral Candidate, Department of Philosophy & Religion Concentration in Philosophy, Cosmology, and Consciousness PARP 9600 – Doctoral Comprehensive Exam Paper Professor Allan Combs School of Consciousness and Transformation Summer Semester 2013 Comp. Exam Part II The Psychophysics of Consciousness The Psychophysics of Consciousness: A Hypothesis Abstract Gustav Fechner, the German experimental psychologist, coined the term psychophysics in 1860, publishing the first mathematical equation to model human consciousness.1 Fechner assumed that any future approaches to consciousness would include mathematical and physical underpinnings. In 1995, the cognitive scientist and philosopher David Chalmers coined the phrase "the hard problem" as being that of connecting consciousness with some physical substrate. According to Chalmers, "The really hard problem of consciousness is the problem of experience. Most existing theories of consciousness either deny the phenomenon, explain something else, or elevate the problem to an eternal mystery."2 As Chalmers points out, unfortunately, the modern scientific community has not yet produced a model of consciousness supported by mathematics and physics, thus no progress in Fecher's "psychophysics." However there is growing interest among the scientific community in string theory, the only branch of mathematical geometry that has successfully explained recent discoveries in high energy particle physics.