The contents of consciousness: A neuropsychological conjecture

Neural correlates of impaired cognitive processes underlying self-unawareness in Alzheimer's disease

Self-unawareness concerning current symptoms remains a clinical challenge in Alzheimer's disease. Reduced self-awareness likely depends on complex biopsychosocial mechanisms that comprise multiple cognitive processes, regulated by personal goals and values. We specifically reviewed the cognitive processes impaired in unaware participants with AD by emphasizing the related impaired brain activity observed during task-based fMRI. Unawareness can be explained by a failure in functioning of or in connection between brain regions that intervene in access, retrieval and updating of (present or extended) self-information (posterior midline, medial temporal, inferior parietal cortices), or in its monitoring, evaluation, or control (medial and lateral prefrontal cortices). Although one must be cautious when relating function to brain regions, impaired processes were tentatively related to the Cognitive Awareness Model. Although brain function depends on neural networks, impaired brain activity during cognitive processes was discussed according to previous studies reporting correlations between brain regions and scores of anosognosia. The review provides a framework to help clinicians considering processes that can explain unawareness in dementia. In patients at early stages of AD, different levels of awareness of cognitive or social clinical changes might be described as impairment in the interaction between specific cognitive processes and contents.

Sliding Scale Theory of Attention and Consciousness/Unconsciousness

Attention defined as focusing on a unit of information plays a prominent role in both consciousness and the cognitive unconscious, due to its essential role in information processing. Existing theories of consciousness invariably address the relationship between attention and conscious awareness, ranging from attention is not required to crucial. However, these theories do not adequately or even remotely consider the contribution of attention to the cognitive unconscious. A valid theory of consciousness must also be a robust theory of the cognitive unconscious, a point rarely if ever considered. Current theories also emphasize human perceptual consciousness, primarily visual, despite evidence that consciousness occurs in diverse animal species varying in cognitive capacity, and across many forms of perceptual and thought consciousness. A comprehensive and parsimonious perspective applicable to the diversity of species demonstrating consciousness and the various forms—sliding scale theory of attention and consciousness/unconsciousness—is proposed with relevant research reviewed. Consistent with the continuous organization of natural events, attention occupies a sliding scale in regards to time and space compression. Unconscious attention in the form of the “cognitive unconscious” is time and spaced diffused, whereas conscious attention is tightly time and space compressed to the present moment. Due to the special clarity derived from brief and concentrated signals, the tight time and space compression yields conscious awareness as an emergent property. The present moment enhances the time and space compression of conscious attention, and contributes to an evolutionary explanation of conscious awareness.

Developing the Concepts of Homeostasis, Homeorhesis, Allostasis, Elasticity, Flexibility and Plasticity of Brain Function

I discuss some concepts advanced for the understanding of the complex dynamics of brain functions, and relate them to approaches in affective, cognitive and action neurosciences. These functions involve neuro-glial interactions in a dynamic system that receives sensory signals from the outside of the central nervous system, processes information in frequency, amplitude and phase-modulated electrochemical waves, and control muscles and glands to generate behavioral patterns. The astrocyte network is in charge of controlling global electrochemical homeostasis, and Hodgkin–Huxley dynamics drive the bioelectric homeostasis of single neurons. In elastic processes, perturbations cause instability, but the system returns to the basal equilibrium. In allostatic processes, perturbations elicit a response from the system, reacting to the deviation and driving the system to stable states far from the homeostatic equilibrium. When the system does not return to a fixed point or region of the state space, the process is called homeorhetic, and may present two types of evolution: (a) In flexible processes, there are previously existing “attractor” stable states that may be achieved after the perturbation, depending on context; (b) In plastic processes, the homeostatic set point(s) is(are) changed; the system is in a process of adaptation, in which the allostatic forces do not drive it back to the previous set point, but project to the new one. In the temporal phase from the deviant state to the recovery of stability, the system generates sensations that indicate if the recovery is successful (pleasure-like sensations) or if there is a failure (pain-like sensations).

Externally controlled involuntary cognitions and their relations with other representations in consciousness

Percepts and action-related urges often enter consciousness insuppressibly. The Reflexive Imagery Task (RIT) was developed to investigate how high-level cognitions (e.g., subvocalizations), too, can enter consciousness in this manner. Limitations of the paradigm include (a) that no data have confirmed subjects' introspections about the involuntary subvocalizations, and (b) that, in everyday life, adaptive responses to involuntary cognitions often depend on the nature of the other contents in consciousness. To address a and b, we developed an RIT in which subjects were presented with visual objects and instructed to not think of the object names. If a subvocalization did arise, however, subjects responded motorically only if the subvocalization rhymed with a word held in memory and if there was a visual "go" cue. Subjects successfully (on 0.83 of the trials) emitted this complex, "multi-determined" response, which provides evidence for the occurrence of the involuntary subvocalizations and illuminates the function of consciousness.

Philosophical Foundations of Neuroscience in Organizational Research: Functional and Nonfunctional Approaches

Neuroscience offers a unique opportunity to elucidate the role of mental phenomena, including consciousness. However the place of such phenomena in explanations of human behavior is controversial. For example, consciousness has been construed in varied and conflicting forms, making it difficult to represent it in meaningful ways without committing researchers to one species of consciousness or another, with vastly different implications for hypothesis development, methods of study, and interpretation of findings. We explore the conceptual foundations of different explications of consciousness and consider alternative ways for studying its role in research. In the end, although no approach is flawless or dominates all others in every way, we are convinced that any viable approach must take into account, if not privilege, the self in the sense of representing the subjective, first-person process of self as observer and knower of one’s own actions and history, and the feelings and meanings attached to these. The most promising frameworks in this regard are likely to be some variant of nonreductive monism, or perhaps a kind of naturalistic dualism that remains yet to be developed coherently.

Traumatic stress, neural self and the spiritual mind

According to recent findings stressful experiences may influence various physiological disturbances and also neuroanatomical changes and some studies also show that psychotherapy and meditation may influence brain functions. Traumatic stress is frequently related to a dissociative response that disintegrates conscious experience. In this context, self-reflection is an essential principle in the process of posttraumatic growth related to spiritual experiences and meditation states that enable mental integration and create the novel integrated self. According to recent findings there is no widely accepted evidence about specific neural mechanisms of processes related to mental integration linked to the spiritual experiences and meditation. Nevertheless there is growing evidence that these integrative experiences are related to various alterations in the brain's physiology and morphology. These findings provide a new paradigm for understanding of mental disorders and emphasize the fundamental role of mental integration and integrated self in the therapy of psychiatric disorders.

Homing in on consciousness in the nervous system: An action-based synthesis

What is the primary function of consciousness in the nervous system? The answer to this question remains enigmatic, not so much because of a lack of relevant data, but because of the lack of a conceptual framework with which to interpret the data. To this end, we have developed Passive Frame Theory, an internally coherent framework that, from an action-based perspective, synthesizes empirically supported hypotheses from diverse fields of investigation. The theory proposes that the primary function of consciousness is well-circumscribed, serving the somatic nervous system. For this system, consciousness serves as a frame that constrains and directs skeletal muscle output, thereby yielding adaptive behavior. The mechanism by which consciousness achieves this is more counterintuitive, passive, and "low level" than the kinds of functions that theorists have previously attributed to consciousness. Passive frame theory begins to illuminate (a) what consciousness contributes to nervous function, (b) how consciousness achieves this function, and (c) the neuroanatomical substrates of conscious processes. Our untraditional, action-based perspective focuses on olfaction instead of on vision and is descriptive (describing the products of nature as they evolved to be) rather than normative (construing processes in terms of how they should function). Passive frame theory begins to isolate the neuroanatomical, cognitive-mechanistic, and representational (e.g., conscious contents) processes associated with consciousness.

Is There Release from Masking from Isomorphism between Perception and Action?

The phenomenon of "entry into awareness" is one of the most challenging puzzles in neuroscience. Research has shown how entry is influenced by processes that are "bottom-up" (e.g., stimulus salience, motion, novelty, incentive and emotional quality) and associated with working memory. Although consciousness is intimately related to action, action-based entry remains under-explored. We review research showing that action-related processing influences the nature of percepts already in conscious awareness and present three experiments that, using a "release-from-masking" technique, examine whether action plans can also influence that which enters awareness in the first place. The present data, though intriguing and consistent with previous research, are not definitive. The limitations and theoretical implications of the findings are discussed. We hope that these experiments will spur further investigation of this understudied topic.

Illusory correlations and control across the psychosis continuum: the contribution of hypersalient evidence-hypothesis matches

It has recently been proposed that individuals with delusions may be hypersalient to evidence-hypothesis matches, which may contribute to the formation and the maintenance of delusions. However, empirical support for the construct is limited. Using cognitive tasks designed to elicit the illusory correlation bias (i.e., perception of a correlation in which none actually exists) and the illusion of control bias (i.e., overestimation of one's personal influence over an outcome), the current article investigates the possibility that individuals with delusions are hypersalient to evidence-hypothesis matches. It was hypothesized that this hypersalience may increase a person's propensity to rely on such illusory correlations and estimates of control. A total of 75 participants (25 participants diagnosed with schizophrenia with a history of delusions, 25 nonclinical participants with delusion proneness, and 25 controls without delusion proneness) completed computerized versions of the "fertilizer" illusory correlation task developed by Kao and Wasserman (J Exp Psychol Learn Mem Cogn 19:1363-1386; 1993) and the "light-onset" illusion of control task created by Alloy and Abramson (J Exp Psychol Gen 108:441-485; 1979). The results across both tasks showed that the participants with schizophrenia were more susceptible than the nonclinical groups to illusory correlations (i.e., higher estimates of covariation between unrelated events) and illusions of control (i.e., higher estimates of control and perceived connection between the responses and the outcome). These results suggest that delusional ideation is linked to a hypersalience of evidence-hypothesis matches. The theoretical implications of this cognitive mechanism on the formation and the maintenance of delusions are discussed.

Cognitive and neural components of the phenomenology of agency

A primary aspect of the self is the sense of agency – the sense that one is causing an action. In the spirit of recent reductionistic approaches to other complex, multifaceted phenomena (e.g., working memory; cf. Johnson &Johnson, 2009), we attempt to unravel the sense of agency by investigating its most basic components, without invoking high-level conceptual or 'central executive' processes. After considering the high-level components of agency, we examine the cognitive and neural underpinnings of its low-level components, which include basic consciousness and subjective urges (e.g., the urge to breathe when holding one's breath). Regarding urges, a quantitative review revealed that certain inter-representational dynamics (conflicts between action plans, as when holding one's breath) reliably engender fundamental aspects both of the phenomenology of agency and of 'something countering the will of the self'. The neural correlates of such dynamics, for both primordial urges (e.g., air hunger) and urges elicited in laboratory interference tasks, are entertained. In addition, we discuss the implications of this unique perspective for the study of disorders involving agency.

The influence of schizophrenia-related neuregulin-1 polymorphisms on sensorimotor gating in healthy males

BACKGROUND

Neuregulin-1 (NRG1) variations have been shown to modulate schizophrenia candidate endophenotypes related to brain structure and function. The objective of this cross-sectional genetic association study was to determine the relationship of six core single-nucleotide polymorphisms within the NRG1 gene identified as promising schizophrenia risk genes (rs6994992, SNP8NRG221132, SNP8NRG241930, rs3924999, rs2439272 and rs10503929) to prepulse inhibition (PPI) of the acoustic startle reflex, a well validated schizophrenia endophenotype.

METHODS

PPI was tested in a highly homogeneous study entry cohort (n = 445) of carefully screened healthy, young male army conscripts originating from the Greek LOGOS project (Learning on Genetics of Schizophrenia Spectrum). The QTPHASE from the UNPHASED package was used for the association analysis of each single-nucleotide polymorphisms or haplotype data.

RESULTS

Reduced PPI, particularly at 75-dB_120-msec and 85-dB_60-msec trials, was related to the SNP8NRG241930 G allele and especially the rs6994992 T allele and rs2439272 C allele. Haplotype analysis followed up by risk versus no-risk groups Analysis of variance confirmed that the rs10503929 and rs3924999 SNPs were also associated with PPI reductions, when combined with rs2439272.

CONCLUSIONS

We provide solid evidence for a role of NRG1 risk genotype variations in PPI reductions in a large and demographically and genetically highly homogeneous cohort of healthy young males. These results further validate NRG1 as a candidate gene for the schizophrenia and spectrum disorders and improve our understanding of its functional mechanisms within the human brain because they suggest an influence of the gene in the neural substrate mediating sensorimotor gating.

The neuropsychology of delusions

Work in the field of cognitive neuropsychiatry over the past 20 years has made it plain that various forms of delusional belief are scientifically understandable in the sense that plausible neuropsychological explanations of their nature and genesis have been formulated. A two-factor theory of delusional belief has emerged from this work. According to this theory, explaining the presence of a delusion requires (a) the presence a neuropsychological impairment that initially prompts the delusional belief and (b) the presence of a second neuropsychological impairment that interferes with processes of belief evaluation that would otherwise cause the delusional belief to be rejected. A very similar account of delusion has recently emerged from research on hypothesis evaluation using the associative-learning paradigm with healthy control subjects and people with psychosis. Neuroimaging studies in this context suggest that the region of the brain specifically involved in hypothesis evaluation (and therefore, according to the two-factor theory, impaired in people with delusions) is the right lateral prefrontal cortex.

Reasoning anomalies associated with delusions in schizophrenia

Deluded people differ from nondeluded controls on attributional style questionnaires and probabilistic-reasoning and theory-of-mind (ToM) tasks. No study to date has examined the relations between these 3 reasoning anomalies in the same individuals so as to evaluate their functional independence and potentially inform theories of delusion formation. We did so in 35 schizophrenic patients with a history of delusions, 30 of whom were currently deluded, and 34 healthy controls. Compared with healthy controls, patients showed (a) a jumping-to-conclusions bias and a bias to overadjust when confronted with a change of evidence on probabilistic-reasoning tasks, (b) an excessive externalizing attributional bias, and (c) performance deficits on 3 ToM tasks. Probabilistic-reasoning and ToM measures correlated, while attributional-bias scores were independent of other task measures. A general proneness to delusional ideation correlated with probabilistic-reasoning and ToM measures, while externalizing bias was unrelated to the study measures of delusional ideation. Personalizing bias associated specifically with paranoia across the clinical and nonclinical participants. Findings are consistent with a common underlying mechanism in schizophrenia which contributes to the anomalies on probabilistic-reasoning and ToM tasks associated with delusions. We speculate that this mechanism is impairment of the normal capacity to inhibit "perceived reality" (the evidence of our senses), a capacity that evolved as part of the "social brain" to facilitate intersubjective communication within a shared reality.

Beauty and belief: William James and the aesthetics of delusions in schizophrenia

INTRODUCTION

This paper proposes the hypothesis that aesthetics plays an important role in the construction and maintenance of delusional ideas in schizophrenia.

METHOD

A selective review of the literature on the cognitive science of aesthetics, beginning with the work of William James on the stream of thought, was undertaken together with a review of some of the cognitive neuroscience literature on delusion formation in schizophrenia.

RESULTS

It is suggested that delusion formation has some similarities to to the creative process, but commences with a proto-psychotic anomalous experience in which an aberrant Jamesian fringe experience is generated. The consequence of such deviation from standard or expected conscious experience is to direct processing resources in a search for meaning, but under conditions of reduced prefrontal cortex monitoring and control mechanisms. Lowering of the usual constraints exercised by prefrontal cortex regulatory mechanisms causes the search for explanation or interpretation to be characterised by low self-reflection, temporal distortion and low volitional control, permitting relatively unfiltered ideas that do not conform to convention to emerge in consciousness. The combination of aberrant Jamesian fringe experience and reduced prefrontal regulatory mechanisms evoke idiosyncratic contextual associations and drive a hypersensitive salience assignment system in the search for meaning, out of which process nascent delusional beliefs emerge. These are accompanied by a 'sense of rightness' in the Jamesian fringe which signals the presence of a 'good fit' between the proto-psychotic anomalous experience in the centre of consciousness and the contextual associations evoked.

CONCLUSION

The 'sense of rightness' or 'good fit' is responsible for the aesthetic qualities of the delusion and, it is proposed, accounts for the incorrigibility of the delusions.

Purpose in Life as a System that Creates and Sustains Health and Well-Being: An Integrative, Testable Theory

Purpose—a cognitive process that defines life goals and provides personal meaning—may help explain disparate empirical social science findings. Devoting effort and making progress toward life goals provides a significant, renewable source of engagement and meaning. Purpose offers a testable, causal system that synthesizes outcomes including life expectancy, satisfaction, and mental and physical health. These outcomes may be explained best by considering the motivation of the individual—a motivation that comes from having a purpose. We provide a detailed definition with specific hypotheses derived from a synthesis of relevant findings from social, behavioral, biological, and cognitive literatures. To illustrate the uniqueness of the purpose model, we compared purpose with competing contemporary models that offer similar predictions. Addressing the structural features unique to purpose opens opportunities to build upon existing causal models of “how and why” health and well-being develop and change over time.

The study of animal metacognition

Do nonhuman animals share humans' capacity for metacognition--that is, for monitoring or regulating their own cognitive states? Comparative psychologists have approached this question by testing a dolphin, pigeons, rats, monkeys and apes using perception, memory and food-concealment paradigms. There is growing evidence that animals share functional parallels with humans' conscious metacognition, although the field has not confirmed full experiential parallels and this remains an open question. This article reviews this new area of comparative inquiry and describes significant empirical milestones, remaining theoretical milestones and the prospects for continuing progress in a rapidly developing area. This research area opens a new window on reflective mind in animals, illuminating its phylogenetic emergence and allowing researchers to trace the antecedents of human consciousness.

Functional magnetic resonance imaging (fMRI) of attention processes in presumed obligate carriers of schizophrenia: preliminary findings

BACKGROUND

Presumed obligate carriers (POCs) are the first-degree relatives of people with schizophrenia who, although do not exhibit the disorder, are in direct lineage of it. Thus, this subpopulation of first-degree relatives could provide very important information with regard to the investigation of endophenotypes for schizophrenia that could clarify the often contradictory findings in schizophrenia high-risk populations. To date, despite the extant literature on schizophrenia endophenotypes, we are only aware of one other study that examined the neural mechanisms that underlie cognitive abnormalities in this group. The aim of this study was to investigate whether a more homogeneous group of relatives, such as POCs, have neural abnormalities that may be related to schizophrenia.

METHODS

We used functional magnetic resonance imaging (fMRI) to collect blood oxygenated level dependent (BOLD) response data in six POCs and eight unrelated healthy controls while performing under conditions of sustained, selective and divided attention.

RESULTS

The POCs indicated alterations in a widely distributed network of regions involved in attention processes, such as the prefrontal and temporal (including the parahippocampal gyrus) cortices, in addition to the anterior cingulate gyrus. More specifically, a general reduction in BOLD response was found in these areas compared to the healthy participants during attention processes.

CONCLUSION

These preliminary findings of decreased activity in POCs indicate that this more homogeneous population of unaffected relatives share similar neural abnormalities with people with schizophrenia, suggesting that reduced BOLD activity in the attention network may be an intermediate marker for schizophrenia.

Realistic expectations of prepulse inhibition in translational models for schizophrenia research

INTRODUCTION

Under specific conditions, a weak lead stimulus, or "prepulse", can inhibit the startling effects of a subsequent intense abrupt stimulus. This startle-inhibiting effect of the prepulse, termed "prepulse inhibition" (PPI), is widely used in translational models to understand the biology of brainbased inhibitory mechanisms and their deficiency in neuropsychiatric disorders. In 1981, four published reports with "prepulse inhibition" as an index term were listed on Medline; over the past 5 years, new published Medline reports with "prepulse inhibition" as an index term have appeared at a rate exceeding once every 2.7 days (n=678). Most of these reports focus on the use of PPI in translational models of impaired sensorimotor gating in schizophrenia. This rapid expansion and broad application of PPI as a tool for understanding schizophrenia has, at times, outpaced critical thinking and falsifiable hypotheses about the relative strengths vs. limitations of this measure.

OBJECTIVES

This review enumerates the realistic expectations for PPI in translational models for schizophrenia research, and provides cautionary notes for the future applications of this important research tool.

CONCLUSION

In humans, PPI is not "diagnostic"; levels of PPI do not predict clinical course, specific symptoms, or individual medication responses. In preclinical studies, PPI is valuable for evaluating models or model organisms relevant to schizophrenia, "mapping" neural substrates of deficient PPI in schizophrenia, and advancing the discovery and development of novel therapeutics. Across species, PPI is a reliable, robust quantitative phenotype that is useful for probing the neurobiology and genetics of gating deficits in schizophrenia.

Computational and noncomputational systems in brain and cognition: can one mask the other?

A theory is developed based on the premise that nonneural processes occur in the brain exemplified as spatial working memory, and is the seat of consciousness. Additionally, wave storage of spatial information, a Bose condensate to support the waves, and the location of wave storage are provided as illustrative, "existence proofs" that a coherent theory can be built along these lines in agreement with the data. The theory can be built argues on functional grounds that a nonneural spatial memory may serve a vital biological function. This article demonstrate how this same non-neural memory can bridge the explanatory gap to consciousness, in agreement with the facts. The article proposes a possible mechanism and location for the nonneural component.

A neural plasticity perspective on the schizophrenic condition

Imbalanced plasticity of neural networks in the brain is proposed to underlie deficits in the integration of efferent and afferent processes in schizophrenia. These deficits affect the priming of the behavior implementing systems by prior knowledge, and thus impair both controlled regulation and automatic activation of mental and motor processes. The sense of self as a distinct entity can consequently be undermined. In predominantly reality-distorting patients, hypo-plasticity of neural connectivity may cause the emergence of highly focused but inflexible patterns of activation in their representation and response systems. This may lead to dominance of prepotent patterns of activity in these systems and a relative inability of higher control systems to bias lower level activity towards congruence with the ongoing cognitive and motor context. By contrast, predominantly disorganized patients are characterized by hyper-plastic connectivity. This leads to a weakening of prepotent response tendencies but also, as in reality-distorting patients, to less effective top-down contextual constraining.

Neural responses to dynamic expressions of fear in schizophrenia

Abnormalities in social functioning are a significant feature of schizophrenia. One critical aspect of these abnormalities is the difficulty these individuals have with the recognition of facial emotions, particularly negative expressions such as fear. The present work focuses on fear perception and its relationship to the paranoid symptoms of schizophrenia, specifically, how underlying limbic system structures (i.e. the amygdala) react when probed with dynamic fearful facial expressions. Seven paranoid and eight non-paranoid subjects (all males) with a diagnosis of schizophrenia took part in functional magnetic resonance imaging study (1.5T) examining neural responses to emerging fearful expressions contrasted with dissipating fearful expressions. Subjects viewed emerging and dissipating expressions while completing a gender discrimination task. Their brain activation was compared to that of 10 healthy male subjects. Increased hippocampal activation was seen in the non-paranoid group, while abnormalities in the bilateral amygdalae were observed only in the paranoid individuals. These patterns may represent trait-related hippocampal dysfunction, coupled with state (specifically paranoia) related amygdala abnormalities. The findings are discussed in light of models of paranoia in schizophrenia.

The perceptual characteristics of voice-hallucinations in deaf people: insights into the nature of subvocal thought and sensory feedback loops

The study of voice-hallucinations in deaf individuals, who exploit the visuomotor rather than auditory modality for communication, provides rare insight into the relationship between sensory experience and how "voices" are perceived. Relatively little is known about the perceptual characteristics of voice-hallucinations in congenitally deaf people who use lip-reading or sign language as their preferred means of communication. The existing literature on hallucinations in deaf people is reviewed, alongside consideration of how such phenomena may fit into explanatory subvocal articulation hypotheses proposed for auditory verbal hallucinations in hearing people. It is suggested that a failure in subvocal articulation processes may account for voice-hallucinations in both hearing and deaf people but that the distinct way in which hallucinations are experienced may be due to differences in a sensory feedback component, which is influenced by both auditory deprivation and language modality. This article highlights how the study of deaf people may inform wider understanding of auditory verbal hallucinations and subvocal processes generally.

Neural correlates of anosognosia for cognitive impairment in Alzheimer's disease

We explored the neural substrate of anosognosia for cognitive impairment in Alzheimer's disease (AD). Two hundred nine patients with mild to moderate dementia and their caregivers assessed patients' cognitive impairment by answering a structured questionnaire. Subjects rated 13 cognitive domains as not impaired or associated with mild, moderate, severe, or very severe difficulties, and a sum score was calculated. Two measures of anosognosia were derived. A patient's self assessment, unconfounded by objective measurements of cognitive deficits such as dementia severity and episodic memory impairment, provided an estimate of impaired self-evaluative judgment about cognition in AD. Impaired self-evaluation was related to a decrease in brain metabolism measured with 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in orbital prefrontal cortex and in medial temporal structures. In a cognitive model of anosognosia, medial temporal dysfunction might impair a comparison mechanism between current information on cognition and personal knowledge. Hypoactivity in orbitofrontal cortex may not allow AD patients to update the qualitative judgment associated with their impaired cognitive abilities. Caregivers perceived greater cognitive impairments than patients did. The discrepancy score between caregiver's and patient's evaluations, an other measure of anosognosia, was negatively related to metabolic activity located in the temporoparietal junction, consistent with an impairment of self-referential processes and perspective taking in AD.

The function of phenomenal states: supramodular interaction theory

Discovering the function of phenomenal states remains a formidable scientific challenge. Research on consciously penetrable conflicts (e.g., "pain-for-gain" scenarios) and impenetrable conflicts (as in the pupillary reflex, ventriloquism, and the McGurk effect [H. McGurk & J. MacDonald, 1976]) reveals that these states integrate diverse kinds of information to yield adaptive action. Supramodular interaction theory proposes that phenomenal states play an essential role in permitting interactions among supramodular response systems--agentic, independent, multimodal, information-processing structures defined by their concerns (e.g., instrumental action vs. certain bodily needs). Unlike unconscious processes (e.g., pupillary reflex), these processes may conflict with skeletal muscle plans, as described by the principle of parallel responses into skeletal muscle (PRISM). Without phenomenal states, these systems would be encapsulated and incapable of collectively influencing skeletomotor action.

Emotion and consciousness: Ends of a continuum

We suggest a united concept of consciousness and emotion, based on the systemic cognitive neuroscience perspective regarding organisms as active and goal-directed. We criticize the idea that consciousness and emotion are psychological phenomena having quite different neurophysiological mechanisms. We argue that both characterize a unified systemic organization of behavior, but at different levels. All systems act to achieve intended behavioral results in interaction with their environment. Differentiation of this interaction increases during individual development. Any behavioral act is a simultaneous realization of systems ranking from the least to the most differentiated. We argue that consciousness and emotion are dynamic systemic characteristics that are prominent at the most and least differentiated systemic levels, correspondingly. These levels are created during development. Our theory is based on both theoretical and empirical research and provides a solid framework for experimental work.

The development of a cognitive model of schizophrenia: Placing it in context

This review provides a historical perspective on a model for schizophrenia based on results of experiments derived from learning theory. It was developed by the author in collaboration with Jeffrey Gray and numerous colleagues, (e.g. [Gray, J.A., McNaughton, N., 2000. The Neuropsychology of Anxiety. second ed. Oxford University Press, Oxford; Hemsley, D.R., 1987a An experimental psychological model for schizophrenia. In: Hafner, H., Gattaz, W.F., Janzarik, W. (Eds.), Search for the Causes of Schizophrenia, vol. 1. Springer, New York, pp. 179-188.; Hemsley, D.R., 1993. A simple (or simplistic?) cognitive model for schizophrenia. Behaviour Research and Therapy 31, 633-646]. It contrasts with earlier cognitive formulations [e.g. Hemsley, D.R., 1975. A two stage model of attention in schizophrenia research. British Journal of Social and Clinical Psychology 14, 81-88], which emphasised a weakening of contextually elicited response biases, and lacked a link to potential neural bases of the disorder. The model emphasizes the need to demonstrate patterns of performance that are not interpretable in terms of the well established 'generalized deficit' manifest in schizophrenia. It proposes that the cognitive disturbance is a change in the way stored material is integrated with sensory input and ongoing motor programmes. In particular, spatial and temporal context fail to activate appropriate stored regularities. A number of possible pathways from the cognitive disturbance to the symptoms of schizophrenia are outlined; again the term 'context' is widely employed. Thus, it has been invoked to explain the occurrence of hallucinations, delusions, thought disorder and disruptions in the sense of personal identity. However the term 'context' is ill-defined and the review indicates the variety of ways in which it may exert its influence. These are unlikely to reflect the operation of a unitary mechanism.

Sequential information processing using time-delay connections in ontogenic CALM networks

In this paper, a variant of the categorization-and-learning-module (CALM) network is presented that is not only capable of categorizing sequential information with feedback, but can adapt its resources to the current training set. In other words, the modules of the network may grow or shrink depending on the complexity of the presented sequence-set. In the original CALM algorithm, modules did not have access to activations from earlier stimulus presentations. To bypass this limitation, we introduced time-delay connections in CALM. These connections allow for a delayed propagation of activation, such that information at a given time will be available to a module at a later timestep. In addition, modules can autonomously add and remove resources depending on the structure and complexity of the task domain. The performance of this ontogenic CALM network with time-delay connections is demonstrated and analyzed using a sample set of overlapping sequences from an existing problem domain.