The anterior cingulate cortex (ACC)has been identified as part of a supervisoryattentional network for selecting alternativemotor programs in response to top-down corticalprocessing, particularly in situationsinvolving conflicting cognitive tasks.Bilateral lesions to the ACC may be causallyassociated with akinetic mutism, where patientsare unable to voluntarily initiate responses.The clinical and neuroanatomical evidence forthis presumed causal association is examined atlength. However, given the many reciprocalprojections between cerebral, motor, limbic andparalimbic structures within the executivesupervisory network, the association ofvoluntary behavior with a particular (...) structure(the ACC) is highly controversial and thereforepremature at this time. Also considered is theclaim that our subjective sense of voluntarycontrol and free will is simply due toour not having conscious access to theunderlying neural computations that precede our decisions and actions. On thecontrary, the distinction between voluntary and involuntary thoughts and actions mayrather be a matter of temporal and directionallag between parallel computations in differentneural areas. Finally, with reference toDennett, there is an extended discussion ofwhether patients with akinetic mutism are (i) conscious automata, (ii) non-intentional systems, and (iii) in azombie-like state. The relevance of (i)–(iii) for the cognitive neuroscientificliterature is then briefly addressed. (shrink)

Subjectivity theories of consciousness take self-reference, somehow construed, as essential to having conscious experience. These theories differ with respect to how many levels they posit and to whether self-reference is conscious or not. But all treat self-referencing as a process that transpires at the personal level, rather than at the subpersonal level, the level of mechanism. -/- Working with conceptual resources afforded by pre-existing theories of consciousness that take self-reference to be essential, several attempts have been made to explain seemingly (...) anomalous cases, especially instances of alien experience. These experiences are distinctive precisely because self-referencing is explicitly denied by the only person able to report them: those who experience them deny that certain actions, mental states, or body parts belong to self. The relevant actions, mental states, or body parts are sometimes attributed to someone or something other than self, and sometimes they are just described as not belonging to self. But all are referred away from self. -/- The cases under discussion here include somatoparaphrenia, schizophrenia, depersonalization, anarchic hand syndrome, and utilization behavior; the theories employed, Higher-Order Thought, Wide Intrinsicality, and Self-Representational. Below I argue that each of these attempts at explaining or explaining away the anomalies fails. Along the way, since each of these theories seeks at least compatibility with science, I sketch experimental approaches that could be used to adduce support for my position, or indeed for the positions of theorists with whom I disagree. -/- In a concluding section I first identify two presuppositions shared by all of the theorists considered here, and argue that both are either erroneous or misleading. Second, I call attention to divergent paths adopted when attempting to explain alienation experiences: some theorists choose to add a mental ingredient, while others prefer to subtract one. I argue that alienation from experience, action, or body parts could result from either addition or subtraction, and that the two can be incorporated within a comprehensive explanatory framework. Finally, I suggest that this comprehensive framework would require self-referencing of a sort, but self-referencing that occurs solely on the level of mechanism, or the subpersonal level. In adumbrating some features of this “subpersonal self,” I suggest that there might be one respect in which it is prior to conscious experience. (shrink)

Most versions of the knowledge argument say that, since scientists observing my brain wouldn't know what my consciousness "is like," consciousness isn't describable as a physical process. Although this argument unwarrantedly equates the physical with the empirically observable, we can conclude, not that consciousness is nonphysical but that consciousness isn't identical with anything empirically observable. But what kind of mind&endash;body relation would render possible this empirical inaccessibility of consciousness? Even if multiple realizability may allow a distinction between consciousness and its (...) physical substrata, why does this distinction make consciousness empirically unobservable? The reason must be that the emotions motivating attention direction, partly constitutive of phenomenal states, are executed, not undergone by self-organizing processes actively appropriating and replacing needed physical substrata; we feel motivations by generating them. But all consciousness is motivated; visual cortex activation is unconscious of red unless the emotional limbic system and anterior cingulate motivatedly "look for" red. Experiencing entails executing motivations. Experimenters do know what subjects' brain events "are like" ---; but from the standpoint of the experimenter's motivational processes. (shrink)

The anterior cingulate cortex (ACC) is a complex and continually evolving brain region that remains a primary focus of research due to its multifaceted functions. Various studies and analyses have significantly advanced our understanding of how the ACC participates in a wide spectrum of memory and cognitive processes. However, despite its strong connections to brain areas associated with hippocampal and olfactory neurogenesis, the functions of the ACC in regulating postnatal and adult neurogenesis in these regions are still (...) insufficiently explored. Investigating the intricate involvement of the ACC in neurogenesis could enhance our comprehension of essential aspects of brain plasticity. This involvement stems from its complex circuitry with other relevant brain regions, thereby exerting both direct and indirect impacts on the neurogenesis process. This review sheds light on the promising significance of the ACC in orchestrating postnatal and adult neurogenesis in conditions related to memory, cognitive behavior, and associated disorders. (shrink)

Anterior cingulate cortex (ACC) is a part of the brain's limbic system. Classically, this region has been related to affect, on the basis of lesion studies in humans and in animals. In the late 1980s, neuroimaging research indicated that ACC was active in many studies of cognition. The findings from EEG studies of a focal area of negativity in scalp electrodes following an error response led to the idea that ACC might be the brain's error detection and (...) correction device. In this article, these various findings are reviewed in relation to the idea that ACC is a part of a circuit involved in a form of attention that serves to regulate both cognitive and emotional processing. Neuroimaging studies showing that separate areas of ACC are involved in cognition and emotion are discussed and related to results showing that the error negativity is influenced by affect and motivation. In addition, the development of the emotional and cognitive roles of ACC are discussed, and how the success of this regulation in controlling responses might be correlated with cingulate size. Finally, some theories are considered about how the different subdivisions of ACC might interact with other cortical structures as a part of the circuits involved in the regulation of mental and emotional activity. (shrink)

I have suggested that the prefrontal cortex constitutes an ?executive committee? with five streams coming from posterior cortex and subcortical areas to five pre-frontal executive regions, each of which chairs at least one on-going ?sub-committee? and vies with the other executives for taking over central control of conscious attention and willed action. It is through the dynamic interaction of this executive committee that unified conscious experiences and a sense of continuous self-identity are created. There is growing evidence (...) that the amygdala-orbitofrontal brain circuit, in particular, is crucial to impulse control, ?knowledge of good and evil,? personality, personhood, and even ?how X-me made Y-me do something.? There are striking examples of the ways that orbitofrontal and anterior cingulate ?committee members? can stage an insurrection against the dorsolateral prefrontal cortex executive chair. (shrink)

This paper presents arguments for considering the anterior cingulate cortex as a critical structure in intentional communication. Different facets of intentionality are discussed in relationship to this neural structure. The macrostructural and microstructural characteristics of ACC are proposed to sustain the uniqueness of its architecture, as an overlap region of cognitive, affective and motor components. At the functional level, roles played by this region in communication include social bonding in mammals, control of vocalization in humans, semantic and (...) syntactic processing, and initiation of speech. The involvement of the anterior cingulate cortex in social cognition is suggested where, for infants, joint attention skills are considered both prerequisites of social cognition and prelinguistic communication acts. Since the intentional dimension of gestural communication seems to be connected to a region previously equipped for vocalization, ACC might well be a starting point for linguistic communication. (shrink)

“The Matrix is a computer-generated dreamworld built to keep us under control” Morpheus, early in The Matrix. “ In dreaming, you are not only out of control, you don’t even know it…I was completely duped again and again the minute my pons, my amygdala, my perihippocampal cortex, my anterior cingulate, my visual association and parietal opercular cortices were revved up and my dorsolateral prefrontal cortex was muffled” ” J. Allan Hobson, The Dream Drugstore, p.64 The Matrix (...) is an exercise in ambivalence, and at the very heart of that ambivalence lies the Dream. In our dreams, we are not in control. Real dreaming, unlike many popular philosophers’ fictions, is an altered state, closely related to the states induced by chemical manipulations such as the use of (certain) medical or recreational drugs. The dreaming brain is not like the wakeful brain. Normal sensory input is blocked, attentional capacities are impaired or lost, memory is distorted, reasoning and logic are weakened, narratives run wild, self-reflection is dampened or destroyed, emotion and instinct are hyperstimulated, and forms of ‘top-down’ willed control and decision-making diluted and easily overwhelmed. (shrink)

Neuronal aggregates involved in conscious awareness are not evenly distributed throughout the CNS but comprise key components referred to as the neural network correlates of consciousness (NNCC). A critical node in this network is the posterior cingulate, precuneal, and retrosplenial cortices. The cytological and neurochemical composition of this region is reviewed in relation to the Brodmann map. This region has the highest level of cortical glucose metabolism and cytochrome c oxidase activity. Monkey studies suggest that the anterior thalamic (...) projection likely drives retrosplenial and posterior cingulate cortex metabolism and that the midbrain projection to the anteroventral thalamic nucleus is a key coupling site between the brainstem system for arousal and cortical systems for cognitive processing and awareness. The pivotal role of the posterior cingulate, precuneal, and retrosplenial cortices in consciousness is demonstrated with posterior cingulate epilepsy cases, midcingulate lesions that de-afferent this region and are associated with unilateral sensory neglect, observations from stroke and vegetative state patients, alterations in blood flow during sleep, and the actions of general anesthetics. Since this region is critically involved in self reflection, it is not surprising that it is similarly a site for the NNCC. Interestingly, information processing during complex cognitive tasks and during aversive sensations such as pain induces efforts to terminate self reflection and result in decreased processing in posterior cingulate and precuneal cortices. (shrink)

Art perception offers action affordances for the self-generated movement of the eyes, the mind, and the emotions; thus some scenes are ’easy to look at', and evoke different kinds of moods depending on what kind of affordances they present for the eyes, the brain, and the action schemas that further the dynamical self-organizing patterns of activity toward which the organism tends, as reflected in its ongoing emotional life. Art can do this only because perception is active rather than passive, and (...) begins with efferent activity in emotional brain areas (e.g. hypothalamus, amygdala, hippocampus and anterior cingulate) which then motivates afferent processing (parietal imaging activity which finally, after a 1/3-second motivational/selective process is complete, resonates with occipital patterns, resulting in perceptual consciousness). The limbic system ’categories’ that motivate the ’looking-for’ of selective attention are categories of utility, to be understood in terms of emotional affordances and whole-organism affective meanings. Art plays with this looking-for, using it to make us engage in different afforded actions that relate to different limbic (emotional) categories. The drawings of children and of the artistically untutored reveal this structure when we fail to ’draw what we see’, drawing instead what we conceptualize that we ought to be seeing. Art teaches us to get beyond this almost complete dominance of habitual categories, and to see things more freshly -- both in the perceptual and in the emotive sphere. Rather than reinforcing our preconceptions, it forces us to see how they affect our view of reality. -/- Because neither perceptions nor emotional responses are really passive ’responses’ at all, art does not cause us to feel a certain way. Instead, we ’use’ art for the purpose of symbolizing our emotions. Our most important feelings are not directly ’about’ the perceptual objects that trigger them. The object in conscious attention during the feeling of an emotion is normally not the intentional object of the emotion, i.e., it is not the object in relation to which our actions could serve the purpose of the emotion. Emotions are not even triggered by simple ’stimuli’, but rather by the meaning for us of a stimulus in a total context determined by ongoing and dynamical organismic purposes. Emotions arise from the total life process, which is a dynamical system -- not as an isolated chemical event or a causal result of a simple stimulus. For this reason, emotions call not just for satiation or pleasure, but for explication; this is why art is different from entertainment or pretty decoration. Visual art affords not only a meaningful, self-directed dance of the eyes, but also a meaningful dance of this emotional explicating process. (shrink)

We have only limited awareness of the system by which we control our actions and this limited awareness does not seem to be concerned with the control of action. Awareness of choosing one action rather than another comes after the choice has been made, while awareness of initiating an action occurs before the movement has begun. These temporal differences bind together in consciousness the intention to act and the consequences of the action. This creates our sense of agency. Activity in (...) the anterior cingulate cortex and medial prefrontal cortex is associated with awareness of our own actions and also occurs when we think about the actions of others. I propose that the mechanism underlying awareness of how our own intentions lead to actions can also be used to represent the intentions that underlie the actions of others. This common system enables us to communicate mental states and thereby share our experiences. (shrink)

Recent findings indicate that complex cognitive functions are organized at a global level in the brain and rely on large-scale information processing requiring functional integration of multiple disparate neural assemblies. The critical question of the integration of distributed brain activities is whether the essential integrative role can be attributed to a specific structure in the brain or whether this ability is inherent to the cognitive network as a whole. The results of the present study show that mean values of the (...) running correlation function in frontal-temporal EEG pairs with one electrode in the anterior cingulate cortex are significantly higher than the same values in other frontal-temporal pairs. These findings indicate a particular role of the ACC in large-scale communication, which could reflect its unique integrative functions in cognitive processing. (shrink)

We have only limited awareness of the system by which we control our actions and this limited awareness does not seem to be concerned with the control of action. Awareness of choosing one action rather than another comes after the choice has been made, while awareness of initiating an action occurs before the movement has begun. These temporal differences bind together in consciousness the intention to act and the consequences of the action. This creates our sense of agency. Activity in (...) the anterior cingulate cortex and medial prefrontal cortex is associated with awareness of our own actions and also occurs when we think about the actions of others. I propose that the mechanism underlying awareness of how our own intentions lead to actions can also be used to represent the intentions that underlie the actions of others. This common system enables us to communicate mental states and thereby share our experiences. (shrink)

_Objective_: Genetic variation, especially polymorphism of the dopamine D4 receptor gene (DRD4), has been linked to deficits in self-regulation and executive functions and to attention deficit hyperactivity disorder (ADHD), and is related to the structural and functional integrity of the default mode network (DMN), the executive control network (ECN) and the sensorimotor network (SMN). The aim of this study was to explore the effects of the 2-repeat allele of the DRD4 gene on brain network connectivity and behaviors in children (...) with ADHD. _Methods_: Using independent component analysis (ICA) and dimension analyses, we examined resting-state functional magnetic resonance imaging (fMRI) data obtained from 52 Asian medicine-naive children with ADHD (33 2-repeat absent and 19 2-repeat present). _Results_: We found that individuals with 2-repeat absent demonstrated increased within-network connectivity in the right precuneus of the DMN, the right middle frontal gyrus (MFG) of the SMN compared with individuals with 2-repeat present. Within the ECN, 2-repeat absent showed decreased within-network connectivity in the left inferior frontal gyrus (IFG) and the left anterior cingulate cortex. A deeper study found that connectivity strength of the left IFG was directly proportional to the Stroop reaction time in 2-repeat absent group, and as well as the right MFG in 2-repeat present group. _Conclusion_: Polymorphisms of the DRD4 gene, specifically 2-repeat allele, had effects on the ECN, the SMN and the DMN, especially in the prefrontal cortex (PFC) circles. ADHD children with DRD4 2-repeat allele have aberrant resting-state within-network connectivity patterns in the left IFG and the right MFG related to dysfunction in inattention symptom. This study provided novel insights into the neural mechanisms underlying the effects of DRD4 2-repeat allele on ADHD. (shrink)

This introductory chapter attempts to clarify the philosophical, empirical, and theoretical bases on which a cognitive neuroscience approach to consciousness can be founded. We isolate three major empirical observations that any theory of consciousness should incorporate, namely (1) a considerable amount of processing is possible without consciousness, (2) attention is a prerequisite of consciousness, and (3) consciousness is required for some specific cognitive tasks, including those that require durable information maintenance, novel combinations of operations, or the spontaneous generation of (...) intentional behavior. We then propose a theoretical framework that synthesizes those facts: the hypothesis of a global neuronal workspace. This framework postulates that, at any given time, many modular cerebral networks are active in parallel and process information in an unconscious manner. An information becomes conscious, however, if the neural population that represents it is mobilized by top-down attentional amplification into a brain-scale state of coherent activity that involves many neurons distributed throughout the brain. The long-distance connectivity of these `workspace neurons' can, when they are active for a minimal duration, make the information available to a variety of processes including perceptual categorization, long-term memorization, evaluation, and intentional action. We postulate that this global availability of information through the workspace is what we subjectively experience as a conscious state. A complete theory of consciousness should explain why some cognitive and cerebral representations can be permanently or temporarily inaccessible to consciousness, what is the range of possible conscious contents, how they map onto specific cerebral circuits, and whether a generic neuronal mechanism underlies all of them. We confront the workspace model with those issues and identify novel experimental predictions. Neurophysiological, anatomical, and brain-imaging data strongly argue for a major role of prefrontal cortex, anterior cingulate, and the areas that connect to them, in creating the postulated brain-scale workspace. (shrink)

An adequate understanding of ‘the self’ and/or ‘primary-process consciousness’ should allow us to explain how affective experiences are created within the brain. Primitive emotional feelings appear to lie at the core of our beings, and the neural mechanisms that generate such states may constitute an essential foundation process for the evolution of higher, more rational, forms of consciousness. At present, abundant evidence indicates that affective states arise from the intrinsic neurodynamics of primitive self-centred emotional and motivational systems situated in subcortical (...) regions of the brain. Accordingly, a neural understanding of ‘the self’ may arise from a study of how various biological value-coding systems converge and interact with coherent brainstem representations of the body and nearby attentional/waking systems of the brain. Affective feelings may be caused by the neurodynamics of basic emotional circuits interacting with the neural schema of bodily action plans. One key brain area where such interactions occur is found within centromedial diencephalic midbrain areas such as the periventricular and periaqueductal gray and nearby tectal and tegmental zones. Here I will envision that a Simple Ego-type Life Form is instantiated in those circuits The ability of this ’primal SELF’ to resonate with primitive emotional values may help yield the raw subjectively experienced feelings of pleasure, lust, anger, hunger, desire, fear, loneliness and so forth. A study of such systems is a reasonable starting point for the neurological analysis of affective feelings, which may lie at the periconscious core of all other forms of animal consciousness. If such a neurodynamic process was an essential neural preadaptation for the emergence of higher levels of consciousness, it may help us close the explanatory gap between brain circuit states and the psychological nature of affective feelings. Thereby, it may also help us conceptualize the nature of psychological binding within higher forms of consciousness in new ways. (shrink)

In recent years, cognitive neuroscientists have began to explore the process of how sensory information gains access to awareness. To further probe this process, event-related functional magnetic resonance imaging was used while testing subjects with a paradigm known as the “attentional blink.” In this paradigm, visually presented information sporadically fails to reach awareness. It was found that the magnitude and time course of activation within the anterior cingulate , medial prefrontal cortex , and frontopolar cortex predicted (...) whether or not information was consciously perceived during the critical period for the attentional blink. These results are discussed in light of a neural framework for conscious processing. (shrink)

Prefrontal cortex is dysregulated in women with restricting anorexia nervosa . It is not known whether appetitive non-conscious stimuli bias cognitive responses in those with RAN. Thirteen women with RAN and 20 healthy controls completed a dorsolateral PFC working memory task and an anterior cingulate cortex conflict task, while masked subliminal food, aversive and neutral images were presented. During the DLPFC task, accuracy was higher in the RAN compared to the HC group, but superior performance was (...) compromised when subliminal food stimuli were presented: errors positively correlated with self-reported trait anxiety in the RAN group. These effects were not observed in the ACC task. Appetitive activation is intact and anxiogenic in women with RAN, and non-consciously interacts with working memory processes associated with the DLPFC. This interaction mechanism may underlie cognitive inhibition of appetitive processes that are anxiety inducing, in people with AN. (shrink)

Mindfulness and accordant interventions are often used as complementary treatments to psychological or psychosomatic problems. This has also been gradually integrated into daily lives for the promotion of psychological well-being in non-clinical populations. The experience of mindful acceptance in a non-judgmental way brought about the state, which was less interfered by a negative effect. Mindfulness practice often begins with focused attention meditation restricted to an inner experience. We postulate that the brain areas related to an interoceptive function would demonstrate (...) an intrinsic functional change after mindfulness training for the mindful novices along with paying more attention to internal processes. To further explore the influence of mindfulness on the organization of the brain regions, both functional connectivity in the voxel and the region of interest level were calculated. In the current study, 32 healthy volunteers, without any meditation experiences, were enrolled and randomly assigned to a mindfulness-based stress reduction group or control group. Participants in the MBSR group completed 8 weeks of mindfulness-based stress reduction and rated their mindfulness skills before and after MBSR. All subjects were evaluated via resting-state functional MRI in both baselines and after 8 weeks. They also completed a self-report measure of their state and trait anxiety as well as a positive and negative affect. Pre- and post-MBSR assessments revealed a decreased amplitude of low-frequency fluctuations in the right anterior cingulate gyrus, left anterior and posterior insula, as well as left superior medial frontal gyrus in MBSR practitioners. Strengthened FC between right anterior cingulate cortex and aIC.R was observed. The mean ALFF values of those regions were inversely and positively linked to newly acquired mindful abilities. Along with a decreased negative affect score, our results suggest that the brain regions related to attention and interoceptive function were involved at the beginning of mindfulness. This study provides new clues in elucidating the time of evaluating the brain mechanisms of mindfulness novices. (shrink)

The neural basis of progress monitoring has received relatively little attention compared to other sub-processes that are involved in goal directed behavior such as motor control and response inhibition. Studies of error-monitoring have identified the dorsal anterior cingulate cortex (dACC) as a structure that is sensitive to conflict detection, and triggers corrective action. However, monitoring goal progress involves monitoring correct as well as erroneous events over a period of time. In the present research, 20 healthy participants (...) underwent fMRI while playing a game that involved monitoring progress towards either a numerical or a visuo-spatial target. The findings confirmed the role of the dACC in detecting situations in which the current state may conflict with the desired state, but also revealed activations in the frontal and parietal regions, pointing to the involvement of processes such as attention and working memory in monitoring progress over time. In addition, activation of the cuneus was associated with monitoring progress towards a specific target presented in the visual modality. This is the first time that activation in this region has been linked to higher-order processing of goal-relevant information, rather than low-level anticipation of visual stimuli. Taken together, these findings identify the neural substrates involved in monitoring progress over time, and how these extend beyond activations observed in conflict and error monitoring. (shrink)

Gil R, Arroyo-Anllo EM, Ingrand P, Gil M, Neau JP, Ornon C, Bonnaud V. Self-consciousness and Alzheimer’s disease. Acta Neurol Scand 2001: 104: 296–300. # Munksgaard 2001. Objectives – To propose a neuropsychological study of the various aspects of self-consciousness (SC) in Alzheimer’s disease. Methods – Forty-five patients with probable mild or moderate AD were included in the study. Severity of their dementia was assessed by the Mini Mental State (MMS). Fourteen questions were prepared to evaluate SC. Results – No (...) significant correlations were found between SC score and educational level, age, and duration of disease. A significant correlation was found between SC score and the severity of dementia, whereas frontal disturbances were just short of the significance threshold. The various aspects of SC were not impaired to the same degree. The most disturbed ones were awareness of cognitive deficiencies, moral judgements and prospective memory. The least disturbed aspects were awareness of identity and of mental representation of the body. Items relating to anosognosia and moral judgements were significantly correlated with the MMS score, whereas affective state, body representation disorders, prospective memory, and capacities for introspection were not related to the severity of the dementia. Consciousness of identity was sound, regardless of MMS score. Conclusions – AD clearly induces an heterogeneous impairment of SC. SC requires a convergence of many neural networks. In AD, neuronal alterations involve many cortical areas and information sent to the associative frontal cortex from memory, language and visuospatial areas is lacking or disturbed. Thus, the sequential order of successive stimuli cannot be maintained by the heteromodal associative cortex (dorsal convexity of the prefrontal cortex), and the supramodal associative cortex (located rostrally in the frontal lobes) is unable to provide reliable monitoring and assessment of simultaneous neural cognitive networks carrying insufficient and inadequate input. The core deficiency in AD patients might be impaired SC equated with the disability to maintain sequential and simultaneous ‘‘attention to life’’. The Self-Consciousness Questionnaire, a clinical scale providing multidimensional measurement, indicates that different aspects of consciousness are not correlated with overall cognitive deficiency as determined by the MMSE. (shrink)

Pain is modulated by cognitive factors, including attention and emotions. In this study we evaluated the distractive effect of aesthetic appreciation on subjectively rated pain and multi-channel evoked potentials induced by CO2 laser stimulation of the left hand in twelve healthy volunteers. Subjects were stimulated by laser in the absence of other external stimulation and while looking at different paintings they had previously rated as beautiful, neutral or ugly. The view of paintings previously appreciated as beautiful produced lower pain (...) scores and a clear inhibition of the P2 wave amplitude, localized in the anterior cingulate cortex; the inhibition of P2 wave amplitude was lesser or not significant during the presentation of the ugly or neutral paintings, respectively. Dipole source localization analysis of the LEP peaks showed significant changes during different conditions, with a shift from the posterior to the anterior right cingulated cortex while looking at paintings previously rated as beautiful. (shrink)

Recent studies have demonstrated neural overlap between resting state activity and self-referential processing. This “rest-self” overlap occurs especially in anterior cortical midline structures like the perigenual anterior cingulate cortex (PACC). However, the exact neurotemporal and biochemical mechanisms remain to be identified. Therefore, we conducted a combined electroencephalography (EEG)-magnetic resonance spectroscopy (MRS) study. EEG focused on pre-stimulus (e.g., prior to stimulus presentation or perception) power changes to assess the degree to which those changes can predict subjects’ perception (...) (and judgment) of subsequent stimuli as high or low self-related. MRS measured resting state concentration of glutamate, focusing on PACC. High pre-stimulus (e.g., prior to stimulus presentation or perception) alpha power significantly correlated with both perception of stimuli judged to be highly self-related and with resting state glutamate concentrations in the PACC. In sum, our results show (i) pre-stimulus (e.g., prior to stimulus presentation or perception) alpha power and resting state glutamate concentration to mediate rest-self overlap that (ii) dispose or incline subjects to assign high degrees of self-relatedness to perceptual stimuli. (shrink)

Mack and Rock show evidence that no consciousperception occurs without a prior attentiveact. Subjects already executing attention taskstend to neglect visible elements extraneous tothe attentional task, apparently lacking evenbetter-than-chance ``implicit perception,''except in certain cases where the unattendedstimulus is a meaningful word or has uniquepre-tuned salience similar to that ofmeaningful words. This is highly consistentwith ``enactive'' notions that consciousnessrequires selective attention via emotional subcortical and limbic motivationalactivation as it influences anterior attentionmechanisms. Occipital activation withoutconsciousness suggests that motivated search,enacted (...) through the organism's subcorticalmotivational functions, is needed beforevisual stimulation engenders consciousness.This enactive view – that searching for,rather than receiving or processing input isthe basis of consciousness – was slow ingaining acceptance lacking empirical evidenceof this kind, combined with thestimulus-response assumption that brain eventssubserving perceptual consciousness must resultfrom transformation of perceptual input ratherthan from the organism's self-regulatedactivity as manifested through subcorticalactivity. Implicit perception occurring withword priming is ``paradoxical'' according to Mackand Rock, suggesting late selection forattention after extensive unconsciousprocessing, while most trials involvingnonverbal rather than verbal images mightsuggest earlier selection, sinceunattended objects are unseen, apparently evenimplicitly. This paper argues that anteriorand subcortical motivational mechanisms play animportant role in early selection; posteriormechanisms then unconsciously enhance signals;if data survive early gating andcorticothalamic enhancement, then still further anterior-limbic loops motivatedlyactivate ``image schemas'' resonating withposterior nonconscious processing; at thatpoint, consciousness occurs. (shrink)

The clinical and para-clinical examination of residual self-consciousness in non-communicative severely brain damaged patients remains exceptionally challenging. Passive presentation of the patient’s own name and own face are known to be effective attention-grabbing stimuli when clinically assessing consciousness at the patient’s bedside. Event-related potential and functional neuroimaging studies using such self-referential stimuli are currently being used to disentangle the cognitive hierarchy of self-processing. We here review neuropsychological, neuropathological, electrophysiological and neuroimaging studies using the own name and own face paradigm (...) obtained in conscious waking, sleep, pharmacological coma, pathological coma and related disorders of consciousness. Based on these results we discuss what we currently do and do not know about the functional significance of the neural network involved in “automatic” and “conscious” self-referential processing. (shrink)

Self‐awareness—knowledge of self and of one's mental states—is of central importance in ensuring the properties constitutive of consciousness in rational beings. A modified Cartesian thesis is defended: that a well‐formed state of self‐conscious wakefulness is such that the present contents of that mind must be insightfully given to its owner. This is demonstrated through investigating four different states in which insight is diminished and consciousness absent or impaired: sleep, trance, intoxication, and psychosis. These states are analytically explored, and the thesis (...) proven in each case. It emerges that the very items that constitute consciousness in unthinking animals, do the same in thinking animals, only in a more developed form. The differentia of the state of self‐conscious wakefulness is analysed into the co‐presence of a syndrome of mutually necessitating properties : self‐knowledge, rationality, freedom, thinking, etc. When this syndrome is conjoined with the availability of the perceptual attention, together with experience, the state is fully constituted. This is the answer to the fundamental question: what is consciousness? (shrink)

Are there brain differences between believers and nonbelievers? In order to investigate the effect of religious beliefs on cognitive control, Michael Inzlicht and his collaborators measured the neural correlates of performance monitoring and affective responses to errors, specifically, the error-related negativity. ERN is a neurophysiological marker occurring within 100 ms of error commission, and generated in the anterior cingulate cortex. The researchers observed that religious conviction is marked by reduced reactivity in the ACC, a cortical system that (...) is involved in the experience of anxiety and is important for self-regulation. Thus, they claimed that these results offer a mechanism for the finding that religion is linked to positive mental health and low rates of mortality. (shrink)

One hypothesis concerning the human dorsal anterior cingulate cortex (ACC) is that it functions, in part, to signal the occurrence of conflicts in information processing, thereby triggering compensatory adjustments in cognitive control. Since this idea was first proposed, a great deal of relevant empirical evidence has accrued. This evidence has largely corroborated the conflict-monitoring hypothesis, and some very recent work has provided striking new support for the theory. At the same time, other findings have posed specific challenges, (...) especially concerning the way the theory addresses the processing of errors. Recent research has also begun to shed light on the larger function of the ACC, suggesting some new possibilities concerning how conflict monitoring might fit into the cingulate's overall role in cognition and action. (shrink)

Individuals with major depressive disorder (MDD) often ruminate about past experiences, especially those with negative content. These repetitive thoughts may interfere with cognitive processes related to attention and conflict monitoring. However, the temporal nature of these processes as reflected in event-related potentials (ERPs) has not been well-described. We examined behavioral and ERP indices of conflict monitoring during a modified flanker task and the allocation of attention during an attentional blink (AB) task in 33 individuals with MDD and 36 (...) healthy controls, and whether their behavioral performance and ERPs varied with level of rumination. N2 amplitude elicited by the flanker task was significantly reduced in participants with MDD compared to healthy controls. Level of self-reported rumination was also correlated with N2 amplitude. In contrast, P3 amplitude during the AB task was not significantly different between groups, nor was it correlated with rumination. No significant differences were found in behavioral task performance measures between groups or by rumination levels. These findings suggest that rumination in MDD is associated with select deficits in cognitive control, particularly related to conflict monitoring. (shrink)

Understanding the neural basis of schizophrenia (SZ) is important for shedding light on the neurobiological mechanisms underlying this mental disorder. Structural and functional alterations in the anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), hippocampus, and medial prefrontal cortex (MPFC) have been implicated in the neurobiology of SZ. However, the effective connectivity among them in SZ remains unclear. The current study investigated how neuronal pathways involving these regions were affected in first-episode SZ using functional magnetic (...) resonance imaging (fMRI). Forty-nine patients with a first-episode of psychosis and diagnosis of SZ—according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision—were studied. Fifty healthy controls (HCs) were included for comparison. All subjects underwent resting state fMRI. We used spectral dynamic causal modeling (DCM) to estimate directed connections among the bilateral ACC, DLPFC, hippocampus, and MPFC. We characterized the differences using Bayesian parameter averaging (BPA) in addition to classical inference (t-test). In addition to common effective connectivity in these two groups, HCs displayed widespread significant connections predominantly involved in ACC not detected in SZ patients, but SZ showed few connections. Based on BPA results, SZ patients exhibited anterior cingulate cortico-prefrontal-hippocampal hyperconnectivity, as well as ACC-related and hippocampal-dorsolateral prefrontal-medial prefrontal hypoconnectivity. In summary, spectral DCM revealed the pattern of effective connectivity involving ACC in patients with first-episode SZ. This study provides a potential link between SZ and dysfunction of ACC, creating an ideal situation to associate mechanisms behind SZ with aberrant connectivity among these cognition and emotion-related regions. (shrink)

Impressions, energy radiated by phenomena in the momentary environmental scene, enter sensory neurons, creating in afferent nerves a data stream. Following Kant, by our inner sense the mind perceives its own thoughts as it ties together sense data into an internalized scene. The mind, residing in the brain, logically a Language Machine, processes and stores items as coded grammatical entities. Kantian synthetic unity in the linguistic brain is able to deliver our experience of the scene as we appear to see (...) it. Uniquely, the brain records its own history, synthesizing a Movie-in-the-Brain, called the Noumenal Cosmos. Attempting thereby to represent the actual Universe, this makes for a sovereign brain that governs itself. The brain is domicile of an Ego, with its selfhood at stake at all times. Yet, it can know itself only by its actions, in which it appears as an actor in its own movie. Phenomena enter garbled, as confused apparitions, and must be put in good form using top–down feedback control by Ego, so that each movie frame makes rational sense within the overall context of the Noumenal Cosmos. A stack of frames is processed typically in 40 Hz rhythm with 300 ms process time each, for about 12 in the stack at any time. Successive neural centers are processing the stack in the brain assembly line, based on data from increasingly global receptive fields. Ego stitches together the movie frames, but only the top frame is in consciousness for 25 ms. The top frame contains the whole scene where the Ego makes an appearance as the actor that imposes Kantian synthetic unity on the scene, merely an assembly of grammatical texts, in a system-internal coded process language, fitting the scene into the Noumenal Cosmos. But Ego observes Ego only to the extent permitted by the objectivity rule, only what it does and thinks, not its true face. From the Noumenal Cosmos, the Ego receives grammatical messages in the internal sense code. They are integrated into a whole in the reaction of the Ego to the momentary scene. The voluntary nature of Ego’s decisions is explained, based on its ability to code in advance its own actions sequentially in time, as it sees fit with a view to an orderly Noumenal Cosmos, records of code being arranged spatially in neural structures. (shrink)

A central debate in philosophy and neuroscience pertains to whether PFC activity plays an essential role in the neural basis of consciousness. Neuroimaging and electrophysiology studies have revealed that the contents of conscious perceptual experience can be successfully decoded from PFC activity, but these findings might be confounded by post- perceptual cognitive processes, such as thinking, reasoning, and decision-making, that are not necessary for con- sciousness. To clarify the involvement of the PFC in consciousness, we present a synthesis of research (...) that has used intracranial electrical stimulation (iES) for the causal modulation of neural activity in the human PFC. This research provides compelling evidence that iES of only certain prefrontal regions (i.e., orbitofrontal cortex and anterior cingu- late cortex) reliably perturbs conscious experience. Conversely, stimulation of anterolateral prefrontal sites, often con- sidered crucial in higher-order and global workspace theories of consciousness, seldom elicits any reportable alterations in consciousness. Furthermore, the wide variety of iES-elicited effects in the PFC (e.g., emotions, thoughts, and olfactory and visual hallucinations) exhibits no clear relation to the immediate environment. Therefore, there is no evidence for the kinds of alterations in ongoing perceptual experience that would be predicted by higher-order or global workspace theories. Nevertheless, effects in the orbitofrontal and anterior cingulate cortices suggest a specific role for these PFC subregions in supporting emotional aspects of conscious experience. Overall, this evidence presents a challenge for higher-order and global workspace theories, which commonly point to the PFC as the basis for con- scious perception based on correlative and possibly confounded information. (shrink)

Merker’s definition of consciousness excludes self-reflective thought, making his proposal for decorticate consciousness not particularly groundbreaking. He suggests that brainstem sites are neglected in current theories of consciousness. This is so because broader definitions of consciousness are used. Split-brain data show that the cortex is important for full-blown consciousness; also, behaviors exhibited by hydranencephaly patients and decorticated rats do not seem to require reflective consciousness.

In the past two decades, reinforcement learning has become a popular framework for understanding brain function. A key component of RL models, prediction error, has been associated with neural signals throughout the brain, including subcortical nuclei, primary sensory cortices, and prefrontal cortex. Depending on the location in which activity is observed, the functional interpretation of prediction error may change: Prediction errors may reflect a discrepancy in the anticipated and actual value of reward, a signal indicating the salience or novelty (...) of a stimulus, and many other interpretations. Anterior cingulate cortex has long been recognized as a region involved in processing behavioral error, and recent computational models of the region have expanded this interpretation to include a more general role for the region in predicting likely events, broadly construed, and signaling deviations between expected and observed events. Ongoing modeling work investigating the interaction between ACC and additional regions involved in cognitive control suggests an even broader role for cingulate in computing a hierarchically structured surprise signal critical for learning models of the environment. The result is a predictive coding model of the frontal lobes, suggesting that predictive coding may be a unifying computational principle across the neocortex. (shrink)

Are there brain differences between believers and nonbelievers? In order to investigate the effect of religious beliefs on cognitive control, Michael Inzlicht and his collaborators measured the neural correlates of performance monitoring and affective responses to errors, specifically, the error-related negativity. ERN is a neurophysiological marker occurring within 100 ms of error commission, and generated in the anterior cingulate cortex. The researchers observed that religious conviction is marked by reduced reactivity in the ACC, a cortical system that (...) is involved in the experience of anxiety and is important for self-regulation. Thus, they claimed that these results offer a mechanism for the finding that religion is linked to positive mental health and low rates of mortality. (shrink)

The current model, based on event-related potential (ERP) studies, posits that the working-memory system is a state of activated long-term memory; this appears comprehensive, but it needs further detailed analysis of functional neural connectivity analysis within the prefrontal cortex (PFC) and between the posterior and prefrontal cortex. Specifically, the role of dorsolateral PFC and anterior cingulate cortex (ACC) is probably critical for PFC's attentional controller. Neural implementation of the executive function in working memory appears critical (...) to build a firm model. (shrink)

The olfactory system was traditionally thought to lack a thalamic relay to mediate top-down influences from memory and attention in other perceptual modalities. Olfactory perception was therefore often described as an outlier among perceptual modalities. It was argued as a result that olfaction was a canonical example of a direct perception. In this paper we review functional and anatomical evidence which demonstrates that olfaction depends on both direct pathway connecting anterior piriform cortex to orbitofrontal cortex and (...) an indirect thalamic circuit connecting posterior piriform cortex and orbitofrontal cortices to the olfactory system. We argue that the indirect corticothalamic circuit has the structure to potentially mediate mediates top-down influences of memory and attention in olfactory perception. This suggests that olfaction is not an outlier after all. (shrink)

The target article highlights the role of the anterior cingulate cortex (ACC) in conflict monitoring, but ACC function may be better understood in terms of the hierarchical organization of behavior. This proposal suggests that the ACC selects extended goal-directed actions according to their learned costs and benefits and executes those behaviors subject to depleting resources.

Humans are unconditionally confronted with social expectations and norms, up to a degree that they, or some of them, have a hard time recognizing what they actually want. This renders them susceptible for introjection, that is, to unwittingly or “unconsciously” mistake social expectations for self-chosen goals. Such introjections compromise an individual’s autonomy and mental health and have been shown to be more prevalent in individuals with rumination tendencies and low emotional self-awareness. In this brain imaging study, we draw on a (...) source memory task and found that introjections, as indicated by imposed tasks that are falsely recognized as self-chosen, involved the bilateral medial prefrontal cortex and the dorsal anterior cingulate cortex. Notably, reduced right MPFC activation within this condition correlated with trait scores of ruminations and reduced emotional self-awareness, but also introversion. Moreover, correct recognition of tasks as self-chosen involved the right MPFC. Accordingly, the right MPFC may play a role in supporting the maintenance of psychological autonomy and counteract introjection, which individuals with certain personality traits seem to be prone to. This research has significant implications for the study of mechanisms underlying autonomous motivation, goal and norm internalization, decision-making, persuasion, education, and clinical conditions such as depression and burnout. (shrink)

For millennia self has been conjectured to be necessary for consciousness. But scant empirical evidence has been adduced to support this hypothesis. Inconsistent explications of “self” and failure to design apt experiments have impeded progress. Advocates of phenomenological psychiatry, however, have helped explicate “self,” and employed it to explain some psychopathological symptoms. In those studies, “self” is understood in a minimalist sense, sheer “for-me-ness.” Unfortunately, explication of the “minimal self” (MS) has relied on conceptual analysis, and applications to psychopathology have (...) been hermeneutic, allowing for many degrees of interpretive latitude. The result is that MS’s current scientific status is analogous to that of the “atom,” at the time when “atom” was just beginning to undergo transformation from a philosophical to a scientific concept. Fortunately, there is now an opportunity to promote a similar transformation for “MS.” Discovery of the brain’s Default Mode Network (DMN) opened the door to neuroimaging investigations of self. Taking the DMN and other forms of intrinsic activity as a starting point, an empirical foothold can be established, one that spurs experimental research and that enables extension of research into multiple phenomena. New experimental protocols that posit “MS” can help explain phenomena hitherto not thought to be related to self, thereby hastening development of a mature science of self. In particular, targeting phenomena wherein consciousness is lost and recovered, as in some cases of Unresponsive Wakefulness Syndrome (UWS), allow for design of neuroimaging probes that enable detection of MS during non-conscious states. These probes, as well as other experimental protocols applied to NREM Sleep, General Anesthesia (GA), and the waking state, provide some evidence to suggest that not only can self and consciousness dissociate, MS might be a necessary precondition for conscious experience. Finally, these findings have implications for the science of consciousness: it has been suggested that “levels of consciousness” (LoC) is not a legitimate concept for the science of consciousness. But because we have the conceptual and methodological tools with which to refine investigations of MS, we have the means to identify a possible foundation—a bifurcation point—for consciousness, as well as the means by which to measure degrees of distance from that foundation. These neuroimaging investigations of MS position us to better assess whether LoC has a role to play in a mature science of consciousness. (shrink)

Multicultural environments require learning multiple number notations wherein some are encountered more frequently than others. This leads to differences in exposure and consequently differences in usage between notations. We find that differential notational usage imposes a significant neurocognitive load on number processing. Despite simultaneous acquisition, forty-two adult binumerate populations, familiar with two positional writing systems namely Hindu Nagari digits and Hindu Arabic digits, reported significantly lower preference and usage for Nagari as compared to Arabic. Twenty-four participants showed significantly increased reaction (...) times and reduced accuracy while performing magnitude comparison tasks in Nagari with respect to Arabic. Functional magnetic resonance imaging revealed that processing Nagari elicited significantly greater activity in number processing and attention networks. A direct subtraction of networks for Nagari and Arabic notations revealed a neural circuit comprising of bilateral intra-parietal sulcus, inferior and mid frontal gyri, fusiform gyrus and the anterior cingulate cortex (FDR p<0.005). Additionally, whole brain correlation analysis showed that activity in the left inferior parietal region was modulated by task performance in Nagari. We attribute the increased activation in Ng to increased task difficulty due to infrequent exposure and usage. Our results reiterate the role of the left intra-parietal sulcus in modulating performance in numeric tasks and highlight that of the attention network for monitoring symbolic notation mode in binumerates. (shrink)

The dorsal anterior cingulate cortex is a key node in the human salience network. It has been ascribed motor, pain-processing and affective functions. However, the dynamics of information flow in this complex region and how it responds to inputs remain unclear and are difficult to study using non-invasive electrophysiology. The area is targeted by neurosurgery to treat neuropathic pain. During deep brain stimulation surgery, we recorded local field potentials from this region in humans during a decision-making task (...) requiring motor output. We investigated the spatial and temporal distribution of information flow within the dACC. We demonstrate the existence of a distributed network within the anterior cingulate cortex where discrete nodes demonstrate directed communication following inputs. We show that this network anticipates and responds to the valence of feedback to actions. We further show that these network dynamics adapt following learning. Our results provide evidence for the integration of learning and the response to feedback in a key cognitive region. (shrink)