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Home , Cognitive neuroscience

Cognitive : Development and prospects

MICHAEL I POSNER1,∗ and SHOBINI RAO2 1Department of , University of Oregon, Eugene, Oregon 97403, USA 2Neuropsychology, NIMHANS, Hosur Road, Bangalore 560 029, India ∗e-mail: [email protected]

The field of cognitive neuroscience has enjoyed an explosive growth following the finding that specific areas could be activated during processing of visual and auditory words. The subse- quent 20 years have provided a variety of techniques that allow the exploration of brain networks related to a large number of cognitive, emotional and social tasks and environments and that have examined the formation and loss of these networks over the human life span. This chapter reviews the various methods developed for noninvasive exploration of function. Substantive contributions are then examined in several areas of particular importance to the Indian research community. These include , , brain development and training. We consider the problems remaining to be explored, and possible practical consequences of the research. Cognitive neuroscience is at the intersection of two prior fields: and neuro- science. Both these fields have had a relatively short history under these names, although both have roots in ancient philosophy [1]. In this chapter, we will examine the modern history of cogni- tive neuroscience, discuss new tools for the noninvasive exploration of the human brain and apply them to several active fields of research. We will attempt to examine both the changes, which cognitive neuroscience has produced in our understanding of the , and in the understand- ing of the brain. In each area, we consider the relevance of the topic to the Indian scientific community.

1. Cognitive neuroscience aspects of linguistics, and philo- sophy under the title ‘’ [7]. Cognitive psychology was developed in the 1960s. Neuroscience began in the 1950s as the incorpo- The work of Herbert Simon and , ration of many fields that were interested in the based upon the general problem solver [2] argued basic study of the brain. While cognitive psycho- that computer programs simulating human perfor- logy mainly studied human beings, the study of the mance could serve as a theory of the mind. The brain, incorporated work from simpler organisms computer metaphor left little scope for studies of whosebrainsweremoreamenabletoanatomical the brain. At about the same time , and physiological methods which were by necessity adapting the mathematical theory of communi- often very invasive. cation [3] were able to develop important empiri- cal demonstrations describing human performance 1.1 Birth of cognitive neuroscience in terms of laws governing the rate of information transfer [4,5]. These studies served as the basis for The name ‘cognitive neuroscience’ was coined by an approach to the mind based on empirical studies George Miller and during the which was synthesized by Ulrich Neisser in his early 1980s, when Gazzaniga developed an Insti- 1967 book Cognitive Psychology [6]. Over the years, tute with that name as part of the grant program of cognitive psychology branched out to incorporate the Sloan Foundation related to cognitive science.

Keywords. ; consciousness; cognitive science; language neuroscience; self regulation.

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The term ‘’, although it had a Table 1. A list of areas of and for broader [8] had come to be associated which studies have indicated neural net- works involved. One selected study of the each network is with studies of the brain and performance of people referenced [12–22]. with various forms of . Although excellent work was done in neuropsychology, parti- Function Selected reference cularly in distinguishing the different functions Arithmetic [12] of the two cerebral hemispheres, its use in brain Autobiographical [13] injury cases made it less influential in understand- Fear [14] ing normal human cognition. Faces [15] It was not until the late 1980s that neuroimag- [16] ing allowed the normal human brain to be studied Object [17] while people carried out the kind of tasks which Reading and Listening [18] were typical in cognitive psychology. The first Reward [19] studies involved the language system [9]. These Self Reference [20] studies used a subtractive method adopted from cognitive psychology to determine activations in Spatial Navigation [21] sensory, motor, phonological, semantic, and atten- Working Memory [22,23] tional operations. Probably the most important overall result was that even for higher mental processes like word semantics and attention there Using high density electrical or magnetic record- were sufficiently common activations to average ings from the scalp in coordination with fMRI, across people. From the work of Karl Lashely [10] it has been possible to work out the time course and Gestalt Psychologists [11], many believed that of these activations and learn something about higher mental processes involved the whole brain the direction of information flow. These studies and did not show any substantial localization. have shown the importance of re-entrant signals The brain areas involved specifically in semantic so that sensory areas may be activated in the processing included left ventral frontal lobe, left first 100 millisecs from sensory input, but may be posterior tempero-parietal cortex, lateral areas of active again by feedback from attentional networks the and the dorsal anterior cingulate. beyond the first 100 millisecs. These potentially Subsequent studies suggested that each area had a overlapping signals make it difficult to determine different function. the significance of any activity without a full under- standing of the network involved. 1.2 Implication for brain and mind These new findings have shown that the long- standing serial model of information flow in the In the twenty years of subsequent imaging studies, human brain from primary sensory to secondary some generalizations have emerged about mental and tertiary association areas is incorrect [23]. processes and about the human brain that supports They also make it more important to understand them. These may be summarized under the head- the control signals that might provide priority to ings of localization, interaction, control, and plas- particular pathways in any given task. The human ticity. Table 1 summarizes many studies involving is a animal. Ancient networks underly- most of the important areas of cognition, emotion ing simpler reflex activity present at birth can be and social interaction. Indeed sometimes the terms reworked through experience allowing much more affective and are used but most plasticity than has previously been supposed [24]. often all fields of research are included in the gene- The activation of many networks are common to ralized use of the term cognitive neuroscience. all people, suggesting their genetic origins. How- While there is substantial agreement on the ever, the efficiency with which these networks carry brain areas activated in studies of attention, out tasks differ among people and provide ample memory and language, there is much less agree- opportunity for brain plasticity to influence per- ment on the exact function of these areas. In addi- formance. Recent studies have shown how gene tion to separate localization the areas activated by environment interaction shapes these individual have to be coordinated to carry out the task. differences. Although in agreement with patient studies, many tasks involved mainly one (e.g. left for language), most tasks involved activations 2. Probing human brain networks in both hemispheres and often in subcortical areas such as the basal ganglia and cerebellum. The In cellular physiology, the idea of a network interaction among these brain areas in terms of net- involves identified that connect to one works has been a major concern of recent studies. another by synapses or in some cases through other COGNITIVE NEUROSCIENCE: DEVELOPMENT AND PROSPECTS 421

set of brain areas serving as the source of the amplification of sensory signals has been impres- sive ([28] for a recent review). It is widely agreed that the frontal eye fields work in conjunction with superior and inferior parietal areas as the cortical nodes of the orienting network. In addition, studies have implicated some subcortical areas including the pulvinar of the thalamus and the superior colli- culus. Most of the studies of this network have involved visual stimuli, but the sources of the attention influences in orienting to other modalities are much the same. Of course the site of amplifi- cation of the sensory message is quite different for each sensory modality. Evidence to date suggests that both maintained alertness during task performance (tonic) and Figure 1. Brain networks underlying attention. One phasic changes induced by a warning signal involv- fronto-parietal network is involved in orienting to sensory ing a subcortical structure, the locus coeruleus that events (circles), while a cingulo-opercular network relates to is the source of the brain’s norepinephrine. A great the resolution of conflict among responses (triangles, exec- utive network), a third network is responsible for achieving deal of evidence [29] indicates that the tonic state the alert state involving norepinepherine from the midbrain depends upon an intact right cerebral hemisphere. (squares). [Adapted from 25]. Lesions in this hemisphere can produce profound difficulty in responding to unexpected targets. Warning signals, however, may have their influence means of communication. Connectionist models, more strongly on the left cerebral hemisphere [30]. inspired by neural networks, have considered units This distinction may reflect a more general divi- at particular levels that influence each other by sion between the hemispheres where rapidly acting direct or reciprocal connections. Imaging of human events are left lateralized while more slowly chang- task performance has identified another level of ing states involve right hemisphere activity. network function, which is clearly related to both Tasks that involve conflict between the models and the underlying cellular structure dimensions competing for control of the output by showing that a number of quite separate brain often provide activation in the anterior cingulate areas must be orchestrated even in a simple task. gyrus and lateral prefrontal areas. It is Each of these areas may be performing a different that the conflict, induced by a stimulus, is represen- computation, which taken together allow perfor- tative of situations where different neural networks mance of the task. Typically cognitive neuroscience compete for control of consciousness or output. regards the set of activations and their connections Because of this we have termed this the execu- as the network that underlies task performance. tive attention network because it regulates the acti- In this section, we use attentional networks as vity in other brain networks involved in thought an illustration of the methods currently available and emotion [31,32]. This network shows a strong to probe the many networks featured in table 1. development in childhood and its maturation is Attentional networks are special in that their pri- related to what in has mary purpose is to influence the operation of other been called self-regulation. brain networks. As illustrated in figure 1, three Individual differences are invariably found in attentional functions for which brain networks have cognitive tasks involving attention. The Atten- been imaged are: alerting which is involved in tion Network Test (ANT) was developed to exam- acquiring and maintaining the alert state; orienting ine individual differences in the efficiency of the to sensory stimuli and executive control involved brain networks in alerting and orienting the exec- in the resolution of conflict between neural sys- utive attention discussed above [33]. The ANT tems and regulating and [9]. uses differences in reaction time (RT) between Although the sites at which attention influence can conditions to measure the efficiency of each net- be demonstrated involve any brain area including work. Each trial begins with a cue (or a blank primary sensory, limbic and motor cortex, as shown interval, in the no-cue condition) that informs the in table 1, the sources of these activations are much participant either that a target will be occurring more limited. soon,orwhereitwilloccurorboth.Thetar- Orienting to sensory events has been better get always occurs either above or below fixation studied of these networks both with imaging [26] and consists of a central arrow, surrounded by and cellular [27] methods. The convergence on the flanking arrows that can either point in the same 422 MICHAEL I POSNER AND SHOBINI RAO

Figure 2. The fronto-parietal network (orienting, online control) and the cingulo-opercular network (executive, set control) are active at rest and undergo a long developmental process shown as graphs for children C (age 9) and A [adapted from 35]. Abbreviations: aI/fO, anterior insula/frontal operculum; aPFC, anterior prefrontal cortex; dACC/msFC, dorsal anterior cingulate cortex/medial superior frontal cortex; dlPFC, dorsolateral prefrontal cortex; dF, dorsal frontal; IPL, inferior parietal lobule; IPS, intraparietal sulcus. direction (congruent) or in the opposite direction of development. Figure 2 illustrates two sets of (incongruent). Subtracting RTs for congruent from connections active at rest: these are a fronto- incongruent target trials provides a measure of parietal (related to orienting) and a cingulo- conflict resolution and assesses the efficiency of opercular (related to executive attention) network. the executive attention network. Subtracting RTs Connections change over the life span. Children obtained in the double-cue condition from RT in show many shorter connections and integration the no-cue condition gives a measure of alerting of the dorsal anterior cingulate in both networks. due to the presence of a warning signal. Subtract- Adults show more segregation of the two networks ing RTs to targets at the cued location (spatial and longer connections. cue condition) from trials using a central cue gives Some of the same brain areas found active during a measure of orienting, since the spatial cue, but rest change when the person is given a task. not the central cue, provides valid information on For example, while the organization of anatomical where a target will occur. areas in alerting and orienting are not fully known, some promising beginnings have taken place. In 2.1 Network connectivity alerting, the source of the attention appears in the locus coeruleus (lc). Cells in the lc have two modes Neural areas found active in studies of functional of processing. One mode is sustained and is per- anatomy must be orchestrated in carrying out any haps related to the tonic level of alertness over real task. One approach to studying this connec- long time intervals. This function is known to tivity uses fMRI to study the correlations between involve the right cerebral hemisphere more strongly active areas [34]. than the left [36]. Alertness is influenced by sen- An important finding was that even at rest, sory events and by the diurnal rhythm. However, common brain areas appear to be active together its voluntary maintenance during task performance (default state). Studies suggest that the connecti- may be orchestrated from the anterior cingulate vity between these areas change over the course [37]. More phasic shifts of alerting can result from COGNITIVE NEUROSCIENCE: DEVELOPMENT AND PROSPECTS 423 presenting any environmental signal. However, if can provide a more detailed account of the orches- the signal is likely to warn about an impending tration of neural networks related to attention or target, this shift results in a characteristic sup- to other networks illustrated in table 1. pression of the intrinsic brain rhythms (e.g. alpha) The activation of brain networks does not mean within a few tens of milliseconds and a strong that all parts of the network are needed to carry out negative wave is (contingent negative variation) the task. In the past, effects of brain lesions have recorded from surface electrodes and that moves been a primary way to indicate brain areas which from a frontal generator towards the sensory areas when lost will prevent the persons from carrying of the hemisphere opposite the expected target. out certain tasks. For example, damage to areas of An analysis of a number of conflict tasks shows the right parietal lobe have led to neglect of the left that the more dorsal part of the anterior cin- side of space in multiple sensory systems. It is now gulate is involved in the regulation of cognitive possible to use brief magnetic pulses applied to the tasks, while the more ventral part of the cin- scalp overlying the brain area of interest (transcor- gulate is involved in regulation of emotion [38]. tical magnetic stimulation TMS) to disrupt parts The microstructure of the organization of the cin- of the network at particular times to observe its gulate has been studied in detail using correla- influences on task performance [42]. In this way, tions between brain areas while the subject rested one can determine what parts of the network are (functional connectivity). Dynamic casual mode- necessary for task performance. ling(DCM)canthenbeusedtohelpdefine Taken together, the methods reviewed above the direction of information within the network. have provided tools for probing human brain net- [39]. These data are related to an analysis of works. In the case of attention, there has been white matter connections in humans using diffusion increasing coordination of these studies with ani- tensor imaging to trace physical connections and mals studies that allow probing of single units and relate them to similar studies in animals [40]. These examination of the micro-circuitry and molecular converging methods are being applied to trace the events related to these activations. connectivity of brain networks both at rest and during task performance [33]. 3. Language

2.2 In the 1970s, behavioral studies using habitua- tion to a repeated stimulus provided evidence that Although the fMRI method has become increas- from birth, infants are able to discriminate basic ingly useful in understanding the sequence of phonemic units not only in their own language but , their speed may be too fast for also in other to which they have never analysis by the relatively slow changes involved been exposed [43]. Studies using these behavio- in imaging based on vascular changes. Another ral methods together with electrical recording way to examine network activity is to use scalp from the scalp have probed some of the early EEG electrodes to record neural activity synchro- development of the phonemic structure underlying nized in different frequency bands. This method language. can be used to separate rapid temporal events, Recently infants have been exposed to lang- for example, it can separate the cue effects from uage while resting in fMRI scanners to examine the target effects in the ANT. There is increas- the brain mechanisms activated by language [44]. ing interest in the various frequencies of electri- The infant language system appears to involve the cal activity involved in correlations between neural same left hemisphere language structures found in areas. For example, in one study using the ANT adults [44]. In one study, infants listened to sen- [41], a spatial cue indicating the location of the tences presented aurally in their language. Brain target produced increased high frequency gamma areas in the superior temporal lobe (Wernicke’s activity (above 30 Hz) about 200 milliseconds after area) and in Broca’s area were active. When the cue presentation. When the cue brought atten- the same sentence was presented after a delay tion to the target location, gamma activity was of 14 seconds, Broca’s area activity increased, as found following the cue, but not following the though this area was involved in the memory target. When the cue indicated the center location trace. It has long been supposed that the early so that a shift of attention was needed following acquisition of language might involve very differ- the target, the gamma activity was present follow- ent mechanisms than are active in adults [45]. Left ing the target. These data suggest that gamma hemisphere lesions in infancy do not produce a activity is associated with orienting attention. It permanent loss of language function as they might may occur 200 millisecs after the cue or only after do in adults. Nonetheless, the new fMRI data sug- the target depending upon when attention shifts. gests the left hemisphere speech areas are involved Taken together, the fMRI, EEG and DTI methods in receptive language in infancy. 424 MICHAEL I POSNER AND SHOBINI RAO

3.1 Phonemes 3.2 Reading

It has been possible to study changes in phonemic Reading is a high level skill and in alphabetic lang- discrimination due to exposure to the native lang- uages such as English, it has properties related to uage at least by ten months of age [46,47]. Infants the phonemic structure of language. There have appear to acquire a sharpened representation of been many studies of reading and much more the native phonemic distinctions [48]. During the is known than can be reviewed here [see 25,56 for same period they also lose the ability to distinguish reviews]. The child’s ability in phonemic awareness representations not made in their own language (e.g. rhyming of auditory words), is a good pre- [49]. At least a part of the loss occurs when the non- dictor of their being able to learn to read alpha- native language requires a distinction that is within betic languages such as English. Adult studies of a single phonemic category in the native language. reading have revealed a neural network An example is the ‘ra-la’ distinction important in involved in the translation of words into meaning. English is lost because it is within a single category Two important nodes of this network are the visual in Japanese [50]. It is as though Japanese no longer word form area, of the left fusiform gyrus and an hear this distinction and even when exposed to area of the left temporal-parietal junction for trans- English they may not improve in distinguishing ‘ra’ lating visual letters into sounds. from ‘la’. Training by several methods [50,51] seems The visual word form area is involved in inte- to improve this ability even in adults, although it grating or chunking visual letters into units of is not known how well this knowledge can be incor- words [57]. The visual word form has been locali- porated into normal daily life communication. zed to the fusiform gyrus of the left hemisphere’s It might be useful to find a way that will pre- visual system. Although there has been some dis- serve the distinctions originally made for the non- pute about the operation it appears to be a part native language during infancy. One study showed of the visual system that becomes expert in deal- that 12 sessions of exposure to a mandarin speaker ing with letters as reading skill develops in later during the first year was effective [52]. A similar childhood. It is thought that without the function- amount of exposure to a computerized version of ing of this area, reading cannot become fluent. For the speaker was not effective, suggesting the impor- example, a patient with a lesion that interrupted tance of social interaction in this early form of the flow of information from the right hemisphere learning. More needs to be learned about how to the visual word form area used letter by letter and whether media presentation can be effective in reading when words were presented left of fixation learning. (going to the right hemisphere), while they read There is also some reason to believe that the words normally when the word was projected to process of phonemic discrimination being deve- the left hemisphere and thus reached the visual loped in infancy is important for later efficient use word form area [58]. Children from 7 to 18 who of spoken and written language [53,54]. Electrical were deficient in reading skills failed to activate recording taken in infancy during the course of this area, but were able to do so after extensive phonemic distinctions [53,54] have been useful in training [59]. predicting later difficulties in language and read- Languages like English that are highly irregu- ing. There is a history of using event related poten- lar at the visual level are heavily dependent upon tials to assess infant deafness early in life and brain areas that translate visual words to sound. being able to do so reliably has been very useful in These areas are at the temporal parietal boundary the development of sign language and other inter- of the left hemisphere. Children who have diffi- ventions to hasten the infants’ ability at commu- culty in learning to read show little activation in nication. Perhaps a similar role will prove to be these phonological areas. However, phonics train- possible for ERPs in the development of methods ing even after 20 sessions can produce relatively to insure a successful phonemic structure in the normal activity in these areas and also improve native language. reading by several grade levels. There have been efforts to develop appropri- The time course of development of the visual ate intervention in later childhood for difficul- word form area in English is important for the ties in the use of language and reading such development of fluent reading. Phonics training as the widely used FASTFORWARD programs often leaves the child with improved decoding skill, [http://www.scilearn.com, 55]. Although there are but with a lack of fluency. Evidence that the visual disputes about exactly why and for what popu- word form develops rather late and first only for lations this method works, it remains important words with which the child is familiar [60], suggests to develop remedies for language difficulties based the importance of continuous practice in reading to upon research. develop fluency [59]. More research is needed on the COGNITIVE NEUROSCIENCE: DEVELOPMENT AND PROSPECTS 425 best methods for developing fluency, particularly of our awareness of a target event. There is clear in non-alphabetic languages. evidence that attention to a visual event increases The multiple languages in India makes of parti- the brain activity associated with it. Most evi- cular importance findings suggesting superior per- dence arises from studies using event related elec- formance of multi-linguals on executive attention trical potentials with visual stimuli and these have scores, such as the Attention Network Test (ANT) clearly shown that early sensory components of the [61,62]. The ties to attention have been sup- visual P1 and N2 (80–150 millisec) ported by the use of ANT to assess differences in are enlarged by the presence of attention [28]. executive attention between mono and bilinguals. As shown in figure 1 focal attention to the A study of Spanish English bilinguals found strong target of a visual search appears to involve a brain advantages over monolingual controls in a wide network that includes the anterior cingulate and variety of executive tasks [63]. One study [64] com- lateral prefrontal areas [33]. Humans have a convic- pared Korean and Chinese native speakers who tion of conscious control that allows us to regulate were bilingual in English with French and Spanish our thoughts, feelings and behaviors in accord with speakers bilingual in English and with English our goals and people believe that voluntary con- monolinguals. Both bilingual groups showed better scious choice guides at least a part of the action we executive attention than monolinguals and, the take. These beliefs have been studied under various Asian group, whose languages differed the most names in different fields of psychology. In cognition, from English, were superior to the Romance biling- cognitive control is the usual name for the volun- uals. This study shows the close ties between lang- tary exercise of intentions, while in developmental uage and attention. It also suggests that the need psychology many of the same issues are studied to select among languages when speaking, as occurs under the name self-regulation [68]. in multilinguals may form one important basis for Imaging studies suggest that whenever we bring training improved executive attention. to mind information, whether extracted from sen- sory input or from memory, we activate the execu- tive attention network. In some studies a whole set 4. Consciousness of frontal areas become activated together forming what is called a global workspace [69]. This global There is a long tradition of the study of consci- workspace becomes active about 300 millisecs after ousness within Eastern and Western philosophy, a target event is presented. It provides the neural however, cognitive neuroscience provides a some- basis for the set of information on which a per- what new perspective on awareness and will,both son is currently working in the process of problem of which have been central to the discussions of solving. consciousness. The distinction between awareness and control An important distinction in studies of aware- (will) is traditional in studies of consciousness. ness [65] is between general knowledge of our envi- However, one form of awareness, focal awareness, ronment (ambient awareness) and detailed focal appears to involve the same underlying mecha- knowledge of a scene (focal awareness). As lay nism as involved in control. In this sense, even people we generally believe that we have full con- though some forms of consciousness (e.g. ambi- scious awareness of our environment, even when ent awareness) may have diverse sources within our focal attention is upon our own internal sensory specific cortex, there is also a degree of thoughts. Experimental studies [66] show us how unity of the underlying mechanisms involving focal much this opinion is in error. In the study of awareness and conscious control. The distinction ‘’ when cues such as motion, that between focal and ambient factors in consciousness normally lead to a shift of attention, are sup- may help to clarify the sense of awareness that can pressed, we have only a small focus for which be present even when detailed accounts of the scene we have full knowledge and even major semantic are not possible as in change blindness [66]. changes in the remainder of the environment are not reported. Change blindness is closely related to studies 5. Genes and experience build networks of visual search which have been prominent in the field of attention and involve an interaction The common nature of brain networks such as between information in the ventral visual pathway those in table 1 among people argue strongly about the object identity and information in the for the role of genes in their construction. This dorsal visual pathway that controls orienting to has led cognitive neuroscience to incorporate data sensory information (for a review, see [67]). Visual from the growing field of human genetics. One search tasks have been important for examining method for doing this relates individual differences what constraints attention provides to the nature to different forms of genes (genetic alleles) that 426 MICHAEL I POSNER AND SHOBINI RAO

Figure 3. A strategy for relating brain networks to underlying molecular events [adapted from 70]. Bottom of figure are psychological functions, these are related to neural networks as shown in brain images and then to differences in protein configuration and genetic variation. may relate to them. Brain activity can serve as an experiences. For example, several genes including intermediate level for relating genes to behavior as the DRD4 gene and the COMT gene have both illustrated in figure 3. shown to interact with aspects of quality of parent- As one example, the Attention Network Test ing. This provides evidence that aspects of the cul- (ANT) was used to examine individual differences ture in which children are raised can influence the in the efficiency of executive attention. Strong heri- way in which genes shape neural networks influenc- tability of the executive network supported the ing child behavior. search for genes related to individual differences in If brain networks are influenced by parenting network efficiently. and other culture influences, it should be possi- The association of the executive network with ble to develop specific training methods that can the neuromodulator dopamine is a way of search- be used to influence underlying brain networks. ing for candidate genes that might relate to the For example, one study tested the effect of train- efficiency of the network [71]. For example, seve- ing during the period of major development of ral studies employing conflict related tasks, found executive attention, which takes place between 4 that alleles of the catechol-o-methyl transferase to 7 years of age [73]. An improvement in conflict (COMT) gene were related to the ability to resolve resolution as measured by the ANT was found in conflict. A number of other dopamine genes have trained children, along with changes in the under- also proven related to this form of attention, in lying network and generalization to other aspects addition, research has suggested that genes related of cognition. EEG data showed clear evidence of to serotonin transmission also influence executive improvement in network efficiency in resolving con- attention ([72] for a summary). It was also possi- flict following training. The N2 component of the ble to show that some of these genetic differences scalp recorded ERP has been shown to arise in the influenced the degree to which the anterior cingu- anterior cingulate and is related to the resolution late was activated during task performance in stud- of conflict [74]. The N2 differences between congru- ies using brain imaging. In the future, as suggested ent and incongruent trials of the ANT were found by figure 3, it may be possible to relate genes to in trained six year olds, that resembled differences specific nodes within neural networks, allowing a found in adults. No such N2 difference was found much more detailed understanding of the origins of in the untrained controls. These data suggest that brain networks. training altered the network for the resolution of While genes are important for common neural conflict in the direction of being more like what is networks and individual differences in efficiency found in adults. There was also a greater improve- there is also an important role for specific ment in in the trained group compared COGNITIVE NEUROSCIENCE: DEVELOPMENT AND PROSPECTS 427 to the control children. This finding suggested that nature exposure [83] (using attention restoration training effects had generalized to a measure of theory) have conducted similar randomized design cognitive processing that is far removed from the using similar before and after assays as those training exercises. used in attention training. These attention state Given the wide range of individual differences in methods appear to achieve similar success to atten- the efficiency of attention, it is expected that atten- tion training in the attention network test and also tion training could be especially beneficial for those help control of stress, improve self-regulation, etc. children with poorer initial efficiency. These could These two training streams represent the differ- be children with pathologies that involve atten- ent traditions/cultures and methodologies in the tional networks, children with genetic backgrounds East (IBMT, mindfulness) and West (practice and associated with poorer attentional performance, or brain plasticity). These techniques provide sup- children raised in different degrees of deprivation. port for the idea that training can provide general changes in brain networks that can lead to wide- spread improvement in cognitive processes. Since it 6. Brain plasticity is likely that the various methods activate different brain networks, imaging may be used to combine Training studies discussed in the last section show methods to produce improved effectiveness. evidence that performance of networks can be altered by experience. This idea has been impor- tant in rehabilitation in cases of brain injury and 7. Future developments psychiatric disorders. It has also led to suggestions for improved for normal people based on Cognitive neuroscience has developed a number ideas coming from cognitive neuroscience. of methods than in concert can link important Brain networks are frequently damaged by neu- aspects of human behavior to underlying neural rological or psychiatric disorders and head trauma. networks and to the cellular and molecular levels Neuro-imaging has made it easier to determine the that underlie them. It is likely that new methods of extent and location of brain damage, so a major imaging will eventually provide more details about area of application of cognitive studies is to the the functioning of the human brain when active treatment of such disorders. The National Institute and in the resting state. One of the major accom- of and Neuroscience (NIMHANS) plishments of cognitive neuroscience is to attract in Bangalore has been a pioneer in these efforts. the attention of physical and mathematical scien- The NIMHANS neuropsychology battery con- tists who are capable of contributing to imaging sists of 21 neuropsychological tests. This battery apparatus and new algorithms. was administered to 540 normal males and females, Imaging and cognitive theory may also con- aged between 16–65 years, including illiterates and tribute to new forms of compensation for brain literates whose educational levels differed widely injuries and pathologies. Already deep brain stimu- [75]. There have been a series of studies using this lation, guided by imaging theories have been used battery before and after training. Improved basic in treatments of depression [84] and in an effort cognitive functions were found using both hospi- to improve the integrative behavior for patients tal based computerized and home based paper and in vegetative neurological states [85]. We can pencil training [76,77]. also expect additional training and state change A number of randomized studies have also shown methods, guided by imaging of what specific brain improvements in attention and memory in normal network(s) are influenced by the method, designed children and adults [78–81]. All these methods to assist people with brain injuries or other forms involve practice in some cognitive skills including of pathology. repetitive trials on tasks similar to what might Interfaces between humans, computers and pros- be tested in schools or cognitive laboratories. All thetic devices are playing an important role in involve a training group showing significantly more extending the sensory and motor capacities of improvement than control groups. The control patients of all kinds [86]. A better understand- groups often involve the same number of laboratory ing of the neuronal networks related to human sessions with training or experiences not thought to capacities could lead us toward improvements in involve the elements of attention working memory these methods and the development of methods used in the experimental group. to extend the cognitive range of normal people in These methods differ considerably from mindful- directions of human improvement. ness training, exposure to nature settings or inte- This chapter is a brief overview of the achieve- grative body-mind training (IBMT), all of which ments and potential of cognitive neuroscience also affect the state of attention. Recently, both during the twenty years of its existence as a IBMT (using body-mind optimization) [82], and scientific discipline. In addition to the technical 428 MICHAEL I POSNER AND SHOBINI RAO

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