_The Physiological Basis of Behaviour_ deals with the basic structures of the central nervous system, the techniques used in neuroscience and examnines how drugs affect the brain.

This book brings together an international group of neuroscientists and philosophers who are investigating how the content of subjective experience is...

Neural Darwinism (ND) is a large scale selectionist theory of brain development and function that has been hypothesized to relate to consciousness. According to ND, consciousness is entailed by reentrant interactions among neuronal populations in the thalamocortical system (the ‘dynamic core’). These interactions, which permit high-order discriminations among possible core states, confer selective advantages on organisms possessing them by linking current perceptual events to a past history of value-dependent learning. Here, we assess the consistency of ND with 16 widely (...) recognized properties of consciousness, both physiological (for example, consciousness is associated with widespread, relatively fast, low amplitude interactions in the thalamocortical system), and phenomenal (for example, consciousness involves the existence of a private flow of events available only to the experiencing subject). While no theory accounts fully for all of these properties at present, we find that ND and its recent extensions fare well. (shrink)

In the past decade, the notion of a neural correlate of consciousness (or NCC) has become a focal point for scientific research on consciousness (Metzinger, 2000a). A growing number of investigators believe that the first step toward a science of consciousness is to discover the neural correlates of consciousness. Indeed, Francis Crick has gone so far as to proclaim that ‘we … need to discover the neural correlates of consciousness.… For this task the primate visual system seems (...) especially attractive.… No longer need one spend time attempting … to endure the tedium of philosophers perpetually disagreeing with each other. Con- sciousness is now largely a scientific problem’ (Crick, 1996, p. 486).2 Yet the question of what it means to be a neural correlate of consciousness is actually far from straightforward, for it involves fundamental empirical, methodological, and _philosophical _issues about the nature of consciousness and its relationship to the brain. Even if one assumes, as we do, that states of consciousness causally depend on states of the brain, one can nevertheless wonder in what sense there is, or could be, such a thing as a neural correlate of consciousness. (shrink)

The search for neural correlates of consciousness (or NCCs) is arguably the cornerstone in the recent resurgence of the science of consciousness. The search poses many difficult empirical problems, but it seems to be tractable in principle, and some ingenious studies in recent years have led to considerable progress. A number of proposals have been put forward concerning the nature and location of neural correlates of consciousness. A few of these include.

The conclusions drawn by Benjamin Libet from his work with collegues on the timing of somatosensorial conscious experiences has met with a lot of praise and criticism. In this issue we find three examples of the latter. Here I attempt to place the divide between the two opponent camps in a broader perspective by analyzing the question of the relation between physical timing, neural timing, and experiential timing. The nervous system does a sophisticated job of recombining and recoding messages (...) from the sensorial surfaces and if these processes are slighted in a theory, it might become necessary to postulate weird operations, including subjective back-referral. Neuroscientifically inspired theories are of necessity still based on guesses, extrapolations, and philosophically dubious manners of speech. They often assume some neural correlate of consciousness as a part of the nervous system that transforms neural activity in reportable experiences. The majority of neuroscientists appear to assume that the NCC can compare and bind activity patterns only if they arrive simultaneously at the NCC. This leads to a search for synchrony or to theories in terms of the compensation of differences in neural delays . This is the main dimension of the Libet discussion. Examples from vision research, such as “temporal-binding-by-synchrony” and the “flash-lag” effect, are then used to illustrate these reasoning patterns in more detail. Alternatively one could assume symbolic representations of time and space that are not coded in their own dimension . Unless such tags are multiplexed with the quality message , one gets a binding problem for tags. One of the hidden aspects of the discussion between Libet and opponents appears to be the following. Is the NCC smarter than the rest of the nervous system, so that it can solve the problems of local sign and timing on its own, or are these pieces of information coded symbolically early on in the system? A supersmart NCC appears to be the assumption of Libet's camp . The wish to distribute the smartness evenly across all stages of processing in the nervous system appears to motivate the opponents. I argue that there are reasons to side with the latter group. (shrink)

Theories of binding have recently come into the focus of the consciousness debate. In this review, we discuss the potential relevance of temporal binding mechanisms for sensory awareness. Specifically, we suggest that neural synchrony with a precision in the millisecond range may be crucial for conscious processing, and may be involved in arousal, perceptual integration, attentional selection and working memory. Recent evidence from both animal and human studies demonstrates that specific changes in neuronal synchrony occur during all of these (...) processes and that they are distinguished by the emergence of fast oscillations with frequencies in the gamma-range. (shrink)

Adult stem cell populations must coordinate their own maintenance with the generation of differentiated cell types to sustain organ physiology, in a spatially controlled manner and over long periods. Quantitative analyses of clonal dynamics have revealed that, in epithelia, homeostasis is achieved at the population rather than at the single stem cell level, suggesting that feedback mechanisms coordinate stem cell maintenance and progeny generation. In the central nervous system, however, little is known of the possible community processes underlying (...) class='Hi'>neural stem cell maintenance. Recent work, in part based on intravital imaging made possible in the adult zebrafish, conclusively highlights that homeostasis in neural stem cell pools may rely on population asymmetry and long‐term spatiotemporal coordination of neural stem cell states and fates. These results suggest that neural stem cell assemblies in the vertebrate brain behave as self‐organized systems, such that the stem cells themselves generate their own intrinsic niche. (shrink)

This paper concerns how motor actions are neurally represented and coded. Action planning and motor preparation can be studied using a specific type of representational activity, motor imagery. A close functional equivalence between motor imagery and motor preparation is suggested by the positive effects of imagining movements on motor learning, the similarity between the neural structures involved, and the similar physiological correlates observed in both imaging and preparing. The content of motor representations can be inferred from motor images at (...) a macroscopic level, based on global aspects of the action and the motor rules and constraints which predict the spatial path and kinematics of movements. A more microscopic neural account calls for a representation of object-oriented action. Object attributes are processed in different neural pathways depending on the kind of task the subject is performing. During object-oriented action, a pragmatic representation is activated in which object affordances are transformed into specific motor schemas. Animal as well as human clinical data implicate the posterior parietal and premotor cortical areas in schema instantiation. A mechanism is proposed that is able to encode the desired goal of the action and is applicable to different levels of representational organization. (shrink)

In previous research Libet discovered that a critical time period for neural activation is necessary in order for a stimulus to become conscious. This necessary time period varies from subject to subject. In this current study, six subjects for whom the time for neural activation of consciousness had been previously determined were administered a battery of psychological tests on the basis of which ratings were made of degree of repressiveness. As hypothesized, repressive subjects had a longer critical time (...) period for neural activation of consciousness, suggesting the possibility that this neurophysiological time factor is a necessary condition for the development of repression. (shrink)

Decision-making is an intricate subject in neuroscience. It is often argued that laboratorial research is not capable of dealing with the necessary complexity to study the issue. Whereas philosophers in general neglect the physiological features that constitute the main aspects of thought and behaviour, I advocate that cutting-edge neuroscientific experiments can offer us a framework to explain human behaviour in its relationship with will, self-control, inhibition, emotion and reasoning. It is my contention that self-control mechanisms can modulate more basic stimuli. (...) Assuming the aforementioned standpoints, I show the physiological mechanisms underlying social assessment and decision-making. I also establish a difference between veridical and adaptive decision-making, useful to create experimental designs that can better mimic the complexity of our day-by-day decisions in more ecologically relevant laboratorial research. Moreover, I analyse some experiments in order to develop an epistemological reflection about the necessary neural mechanisms to social assessment and decision-making. (shrink)

Decision-making is an intricate subject in neuroscience. It is often argued that laboratorial research is not capable of dealing with the necessary complexity to study the issue. Whereas philosophers in general neglect the physiological features that constitute the main aspects of thought and behaviour, I advocate that cutting-edge neuroscientific experiments can offer us a framework to explain human behaviour in its relationship with will, self-control, inhibition, emotion and reasoning. It is my contention that self-control mechanisms can modulate more basic stimuli. (...) Assuming the aforementioned standpoints, I show the physiological mechanisms underlying social assessment and decision-making. I also establish a difference between veridical and adaptive decision-making, useful to create experimental designs that can better mimic the complexity of our day-by-day decisions in more ecologically relevant laboratorial research. Moreover, I analyse some experiments in order to develop an epistemological reflection about the necessary neural mechanisms to social assessment and decision-making. (shrink)

Interactionists hold that minds are non-physical objects that interact with brains. The neural discernment problem for interactionism is that of explaining how non-physical minds produce behavior and cognition by exercising different causal powers over physiologically similar neurons. This paper sharpens the neural discernment problem and proposes two interactionist models of mind-brain interaction that solve it. One model avoids overdetermination while the other respects the causal closure of the physical domain.

Sensory feedback, which can be presented in different modalities - single and combined, aids task performance in human-robot interaction (HRI). However, combining feedback modalities does not always lead to optimal performance. Indeed, it is not known how feedback modalities affect operator performance under stress. Furthermore, there is limited information on how feedback affects neural processes differently for males and females and under stress. This is a critical gap in the literature, particularly in the domain of surgical robotics, where surgeons (...) are under challenging socio-technical environments that burden them physiologically. In the present study, we posited operator performance as the summation of task performance and neurophysiological cost of maintaining that performance. In a within-subject design, we used functional near-infrared spectroscopy (fNIRS) to assess cerebral activations of 12 participants who underwent a 3D manipulation task within a virtual environment with concurrent feedback (visual and visual + haptic) in the presence and absence of a cognitive stressor. Cognitive stress was induced with the serial-7 subtraction test. We found that while task performance was higher with visual than visual + haptic feedback, it degraded under stress. The two feedback modalities were found to be associated with varying neural activities and neural efficiencies, and these were stress- and gender-dependent. Our findings engender further investigation into effectiveness of feedback modalities on males and females under stressful conditions in HRI. (shrink)

I argue, contrary to wide-spread opinion, that belief-desire psychology is likely to reduce smoothly to neuroscientific theory. I therefore reject P.M. Churchland's eliminativism and Fodor's nonreductive materialism. The case for this claim consists in an example reduction of the desire construct to a suitable construct in neuroscience. A brief account of the standard view of intertheoretic reduction is provided at the outset. An analysis of the desire construct in belief-desire psychology is then undertaken. Armed with these tools, the paper moves (...) to an examination of the neural structures responsible for the production of motor behavior. This examination provides the basis for a theory of the neurophysiology of desire. A neurophysiological state is isolated and claimed to be type-identical to the state of desiring. (shrink)

In this paper I criticize a view of functional localization in neuroscience, which I call “computational absolutism”. “Absolutism” in general is the view that each part of the brain should be given a single, univocal function ascription. Traditional varieties of absolutism posit that each part of the brain processes a particular type of information and/or performs a specific task. These function attributions are currently beset by physiological evidence which seems to suggest that brain areas are multifunctional—that they process distinct information (...) and perform different tasks depending on context. Many theorists take this contextual variation as inimical to successful localization, and claim that we can avoid it by changing our functional descriptions to computational descriptions. The idea is that we can have highly generalizable and predictive functional theories if we can discover a single computation performed by each area regardless of the specific context in which it operates. I argue, drawing on computational models of perceptual area MT, that this computational version of absolutism fails to come through on its promises. In MT, the modeling field has not produced a univocal computational description, but instead a plurality of models analyzing different aspects of MT function. Moreover, CA cannot appeal to theoretical unification to solve this problem, since highly general models, on their own, neither explain nor predict what MT does in any particular context. I close by offering a perspective on neural modeling inspired by Nancy Cartwright’s and Margaret Morrison’s views of modeling in the physical sciences. (shrink)

The integrated information theory equates levels of consciousness with the amount of information integrated over the elements that constitute a system. Conscious visual perception provides two observations that contradict the IIT. First, objects are accurately perceived when presented for ≪100 ms during which time no neural integration is possible. Second, an object is seen as an integrated whole and, concurrently, all constituent elements are evident. Because integration destroys information about details, IIT cannot account for perceptual detail preservation.

In spite of enormous recent interest in the neurobiology of the self, we currently have no global models of the brain that explain how its anatomical structure, connectivity, and physiological functioning create a unified self. In this article I present a triadic neurohierarchical model of the self that proposes that the self can be understood as the product of three hierarchical anatomical systems: The interoself system, the integrative self system, and the exterosensorimotor system. An analysis of these three systems and (...) their functional features indicates that the neural hierarchy possesses features of both non-nested and nested hierarchies that are necessary for the creation of a unified consciousness and self. These functional properties also make the central nervous system a biologically unique entity unlike anything else in nature. (shrink)

Certain features of Stage NREM sleep – for example, rhythmic voltage oscillation in thalamic neurons – are physiologically inhospitable to “REM sleep processes.” In Stage 2, the sleep spindle and its refractory period must limit the incursion of “covert REM,” and thus the extent of REM-like cognition. If these hyperpolarization-dependent events also inform Stage NREM cognition, does a “1-gen” model suffice to account for REM-NREM differences? [Nielsen].

This chapter surveys a few of the so-called “easy” problems, as referred to by Chalmers, in understanding color perception. The obscurity of psycho-neural isomorphism is highlighted by the difficulties encountered in the domain of color, and while this theme has been discussed extensively, the discussion here at least provides an opportunity to review interesting facts and ideas about color vision. Trichromacy is considered first in this chapter, since it provides the most familiar example of physiological explanation in perception—an explanation (...) generally held to be straightforward, simple, and completely satisfactory. However, as is shown in the latter part of this chapter, the neural basis of trichromacy is not yet well understood. The prospects for physiological explanation of less elementary aspects of color vision are also discussed in broad terms, and the conclusions reached here are also discouraging for current theoretical perspectives. (shrink)

We use the phrase "moral intuition" to describe the appearance in consciousness of moral judgments or assessments without any awareness of having gone through a conscious reasoning process that produces this assessment. This paper investigates the neural substrates of moral intuition. We propose that moral intuitions are part of a larger set of social intuitions that guide us through complex, highly uncertain and rapidly changing social interactions. Such intuitions are shaped by learning. The neural substrates for moral intuition (...) include fronto-insular, cingulate, and orbito-frontal cortices and associated subcortical structure such as the septum, basil ganglia and amygdala. Understanding the role of these structures undercuts many philosophical doctrines concerning the status of moral intuitions, but vindicates the claim that they can sometimes play a legitimate role in moral decision-making. (shrink)

The classic modern statement of mind-body interactionism. In Carpenter's view, not only is mental activity the direct result of the physiological activity of the nervous system, the course of neural activity can in its turn be influenced by the occurrence of mental events.

Mental timing studies may be influenced by powerful cognitive illusions that can produce an asymmetry in their rate of progress relative to neuronal timing studies. Both types of timing research are also governed by a temporal asymmetry, expressed by the fact that the direction of causation must follow time's arrow. Here we refresh our earlier suggestion that the temporal asymmetry offers promise as a means of timing mental activities. We update our earlier analysis of Libet's data within this framework. Then (...) we consider the surprises which often occur on those rare occasions when neural timing experiments parallel mental timing work exactly. Together, these surprises and asymmetries prescribe a relentlessly meticulous and fully transparent exposition of timing methods, terms, and concepts which shuns plausible narratives, even when buttressed by rigorous formal models, unless guided by apposite empirical evidence. (shrink)

The human brain is the first computer to which all others are compared. Yet we know painfully little about how a brain accomplishes its peculiar computations. In particular, consciousness is at once familiar and mysterious, and needs to be understood both for science and for medicine. Boldly, but gently this book introduces a reader to the neural circuitry that achieves consciousness. This amazing interconnection enables consciousness to flow like a stream, intimately relevant to the outside world; and for this (...) to happen, fundamental cues emerge from mental images to bring forth associated recalls. Alas cues can be inconsistent, causing memory failure; fortunately a subliminal cue editor encourages remembering forgotten items. Furthermore, cues generally address several memories, forcing the brain to make a selection. This necessitates another special circuit whose purpose is subliminal editing. The simplified explanations provided in this book make it clear that neurons do far more than ordinary devices, since a single neuron is capable of remarkably dense combinational and sequential logic. Beginning with their interesting and unexpected logical behavior, the reader will genuinely enjoy Dr. Burger's synthesis of a system for biological consciousness, a system that may someday result in credible artificial consciousness. (shrink)

In this paper, I argue that looking at the concept of neural function through the lens of cognition alone risks cognitive myopia: it leads neuroscientists to focus only on mechanisms with cognitive functions that process behaviorally relevant information when conceptualizing “neural function”. Cognitive myopia tempts researchers to neglect neural mechanisms with noncognitive functions which do not process behaviorally relevant information but maintain and repair neural and other systems of the body. Cognitive myopia similarly affects philosophy of (...) neuroscience because scholars overlook noncognitive functions when analyzing issues surrounding e.g., functional decomposition or the multifunctionality of neural structures. I argue that we can overcome cognitive myopia by adopting a patchwork approach that articulates cognitive and noncognitive “patches” of the concept of neural function. Cognitive patches describe mechanisms with causally specific effects on cognition and behavior which are likely operative in transforming sensory or other inputs into motor outputs. Noncognitive patches describe mechanisms that lack such specific effects; these mechanisms are enabling conditions for cognitive functions to occur. I use these distinctions to characterize two noncognitive functions at the mesoscale of neural circuits: subsistence functions like breathing are implemented by central pattern generators and are necessary to maintain the life of the organism. Infrastructural functions like gain control are implemented by canonical microcircuits and prevent neural system damage while cognitive processing occurs. By adding conceptual patches that describe these functions, a patchwork approach can overcome cognitive myopia and help us explain how the brain’s capacities as an information processing device are constrained by its ability to maintain and repair itself as a physiological apparatus. (shrink)

Identifying the physiological processes in the central nervous system that underlie our conscious experiences has been at the forefront of cognitive neuroscience. While the principles of classical physics were long found to be unaccommodating for a causally effective consciousness, the inherent indeterminism of quantum physics, together with its characteristic dichotomy between quantum states and quantum observables, provides a fertile ground for the physical modeling of consciousness. Here, we utilize the Schrödinger equation, together with the Planck-Einstein relation between energy and frequency, (...) in order to determine the appropriate quantum dynamical timescale of conscious processes. Furthermore, with the help of a simple two-qubit toy model we illustrate the importance of non-zero interaction Hamiltonian for the generation of quantum entanglement and manifestation of observable correlations between different measurement outcomes. Employing a quantitative measure of entanglement based on Schmidt decomposition, we show that quantum evolution governed only by internal Hamiltonians for the individual quantum subsystems preserves quantum coherence of separable initial quantum states, but eliminates the possibility of any interaction and quantum entanglement. The presence of non-zero interaction Hamiltonian, however, allows for decoherence of the individual quantum subsystems along with their mutual interaction and quantum entanglement. The presented results show that quantum coherence of individual subsystems cannot be used for cognitive binding because it is a physical mechanism that leads to separability and non-interaction. In contrast, quantum interactions with their associated decoherence of individual subsystems are instrumental for dynamical changes in the quantum entanglement of the composite quantum state vector and manifested correlations of different observable outcomes. Thus, fast decoherence timescales could assist cognitive binding through quantum entanglement across extensive neural networks in the brain cortex. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 9.3 (2002) 265-269 [Access article in PDF] The Psychology and Physiology of Depression Walter Glannon Trauma and stressful events can disrupt the physiologic homeostasis of our bodies and brains. The physiologic stress response consists of neural and endocrine mechanisms whose function is to reestablish homeostasis. These mechanisms include the secretion of glucocorticoids (cortisol) and catecholemines (epinephrine and norepinephrine). Once an external event has (...) ceased to be a stressor or threat to a human organism, an integrated system of negative feedback loops inhibits the continued production of these hormones and effectively shuts down the stress response. These mechanisms are adaptive in the sense that they ensure the survival of the organism by reestablishing homeostasis. But prolonged exposure to real or perceived stressors can trigger prolonged secretion of stress hormones, thereby disrupting the feedback systems and causing a cascade of pathogenic events. The stress response is a double-edged sword. An acute stress response can protect an organism from external threats and reestablish homeostasis. But a chronic stress response can cause the body's defenses to become damaging rather than protective and to result in various disorders. Acute stress responses are adaptive. Chronic stress responses are often maladaptive and pathogenic.In "Depression as a Mind-Body Problem," I characterized major clinical depression as a disorder resulting from a maladaptive chronic stress response (Glannon 2003). Specifically, I argued that depression often results when our beliefs and emotions are out of proportion to the true nature of external events. The mind prolongs rather than constrains the physiologic stress response. Depression is not a disorder of the brain alone or the mind alone, however. Endocrine and immune dysfunction can contribute to the dysfunction in the brain and central nervous system that are involved in depression. Moreover, the contents of the mental states that initiate the sequence of events leading to depression are reflections of the person's natural and social environment. Thus, a satisfactory account of depression requires an analysis of the interconnections among the central nervous, endocrine, and immune systems, as well as the mind and the environment. All of these factors support the description of depression as a psychoneuroimmunologic disorder.Mike Martin (Martin 2003) and Thomas Fuchs (Fuchs 2003) discuss important aspects of depression that I did not elaborate in my paper. Martin argues that I fail to distinguish between depression as a mood and depression as a disorder. This is pertinent to the distinction evolutionary psychiatrists draw between moods that are adaptive and moods that are maladaptive. In contrast to my negative characterization of depression, Martin also makes a case for the positive [End Page 265] contributions of depression to meaningful life. Fuchs explores the notion of the brain as an organ of translation enabling patients to have meaningful subjective experience. The emphasis on subjectivity has important implications for potential preventive and therapeutic interventions for depression. For whether a person perceives an external event as a stressor may play a crucial role in the physiologic stress response. I will address the main points of these two authors in turn.Contrary to what Martin claims, I explicitly defined chronic depression as an affective (mood) disorder. My focus was on the clinical definition of major depression as a moderately severe to severe chronic disorder. It consists of affective, cognitive, and even physical dysfunction that interferes with a person's ability to carry out the normal tasks of daily life. This characterization of major chronic depression distinguishes it from milder forms of depression, such as dysthymia. Because these milder forms do not involve the same type or degree of dysfunction as more severe forms, they are not appropriately characterized as pathologies. For this reason, I focused on Nesse's (2000) discussion of depression rather than on his discussion of low mood. In fairness to Nesse and Stevens and Price (2000), not all forms of depression are pathologic according to the evolutionary view they defend. Some passive aspects of mild depression may be useful in alerting us to dangerous or wasteful behavior. It does seem plausible to describe depressed moods as falling along a continuum from those that... (shrink)

Although great progress in neuroanatomy and physiology has occurred lately, we still cannot go directly to those levels to discover the neural mechanisms of higher cognition and consciousness. But we can use neurocomputational methods based on these details to push this project forward. Here we describe vector subtraction as an operation that computes sequential paths through high-dimensional vector spaces. Vector-space interpretations of network activity patterns are a fruitful resource in recent computational neuroscience. Vector subtraction also appears to be (...) implemented neurally in primate frontal eye field activity, which computes dimensions of saccadic eye movements. We use this apparent neural implementation as a model and construct from it a general neurocomputational account of an important type of sequential cognitive and conscious process. We defend the biological plausibility of all components of the general model and show that it yields testable anatomical and physiological predictions. We close by suggesting some interesting consequences for consciousness if our model characterizes correctly the neural mechanisms producing a common type of episode in our conscious streams. (shrink)

In the present paper we present a short review of some recent neuro- physiological and neuropsychological findings which suggest that self-generated actions and actions of others are mapped on the same neural substratum. Since this substratum is neutral with respect to the agent, correctly attributing an action to its proper author requires the co-activation of areas specific to the self and the other. A conceptual analysis of the empirical data will lead us to conclude that from a neurobiological point (...) of view the problem is not 'how is it possible to share the intentions of others', but rather 'how one can distinguish one's own action/intention from those of other people'. (shrink)

A physical model was utilized to show that the neural system can memorize a target position and is able to cause motor and sensory events that move the arm to a target with more accuracy. However, this cannot indicate in which coordinates the necessary computations are carried out. Turning off the lights causes the error to increase which is accomplished by cutting off one feedback path. The geometrical properties of arm kinematics and the properties of the kinesthetic and visual (...) sensorial systems should be better known before inferences about higher levels of processing can be drawn. (shrink)

D‐amino acids are being recognized as functionally important molecules in mammals. We recently identified endogenous D‐cysteine in mammalian brain. D‐cysteine is present in neonatal brain in substantial amounts (mM) and decreases with postnatal development. D‐cysteine binds to MARCKS and a host of proteins implicated in cell division and neurodevelopmental disorders. D‐cysteine decreases phosphorylation of MARCKS in neural progenitor cells (NPCs) affecting its translocation. D‐cysteine controls NPC proliferation by inhibiting AKT signaling. Exogenous D‐cysteine inhibits AKT phosphorylation at Thr 308 and (...) Ser 473 in NPCs. D‐cysteine treatment of NPCs led to 50% reduction in phosphorylation of Foxo1 at Ser 256 and Foxo3a at Ser 253. We hypothesize that in the developing brain endogenous D‐cysteine is as a physiologic regulator of NPC proliferation by inhibiting AKT signaling mediated by Foxo1 and Foxo3a. Endogenous D‐cysteine may regulate mammalian neurodevelopment with roles in schizophrenia and Alzheimer's disease (AD). (shrink)

It is proposed that a human conscious experience of the sort we report to each other reflects a direct causal interaction between a pattern of information about the world, encoded in a field of postsynaptic potentials, and a quantized mode of excitation occupying dendritic cytoskeleton. The requirement for a quantized account is seen simply as the need for an event of experience to be a single indivisible, but richly patterned, causal relation between information and an 'informee'. It is argued that (...) the informee is likely to be a higher-order quantized collective mode (much as proposed by Craddock and colleagues, 2017) with the biologically relevant dynamics likely also to be describable in classical terms. No specific interpretation of quantum theory is needed. In this scenario, anaesthetics would abrogate reportable experience by detuning parameters underpinning cytoskeletal informee modes, perhaps critically increasing associated impedence. It is also proposed that tuning and detuning of informee modes in individual dendritic trees by binding of accessory proteins to cytoskeleton plays a physiological role in short-term memory and truth evaluation through ascertainment of sequential signal pattern consonance. Components of this model may be involved in cellular adaptive responses in many types of organism. (shrink)

Emotions are multimodal processes that play a crucial role in our everyday lives. Recognizing emotions is becoming more critical in a wide range of application domains such as healthcare, education, human-computer interaction, Virtual Reality, intelligent agents, entertainment, and more. Facial macro-expressions or intense facial expressions are the most common modalities in recognizing emotional states. However, since facial expressions can be voluntarily controlled, they may not accurately represent emotional states. Earlier studies have shown that facial micro-expressions are more reliable than facial (...) macro-expressions for revealing emotions. They are subtle, involuntary movements responding to external stimuli that cannot be controlled. This paper proposes using facial micro-expressions combined with brain and physiological signals to more reliably detect underlying emotions. We describe our models for measuring arousal and valence levels from a combination of facial micro-expressions, Electroencephalography (EEG) signals, galvanic skin responses (GSR), and Photoplethysmography (PPG) signals. We then evaluate our model using the DEAP dataset and our own dataset based on a subject-independent approach. Lastly, we discuss our results, the limitations of our work, and how these limitations could be overcome. We also discuss future directions for using facial micro-expressions and physiological signals in emotion recognition. (shrink)

There is some complementarity of models for the origin of the electroencephalogram (EEG) and neural network models for information storage in brainlike systems. From the EEG models of Freeman, of Nunez, and of the authors' group we argue that the wavelike processes revealed in the EEG exhibit linear and near-equilibrium dynamics at macroscopic scale, despite extremely nonlinear – probably chaotic – dynamics at microscopic scale. Simulations of cortical neuronal interactions at global and microscopic scales are then presented. The simulations (...) depend on anatomical and physiological estimates of synaptic densities, coupling symmetries, synaptic gain, dendritic time constants, and axonal delays. It is shown that the frequency content, wave velocities, frequency/wavenumber spectra and response to cortical activation of the electrocorticogram (ECoG) can be reproduced by a “lumped” simulation treating small cortical areas as single-function units. The corresponding cellular neural network simulation has properties that include those of attractor neural networks proposed by Amit and by Parisi. Within the simulations at both scales, sharp transitions occur between low and high cell firing rates. These transitions may form a basis for neural interactions across scale. To maintain overall cortical dynamics in the normal low firing-rate range, interactions between the cortex and the subcortical systems are required to prevent runaway global excitation. Thus, the interaction of cortex and subcortex via corticostriatal and related pathways may partly regulate global dynamics by a principle analogous to adiabatic control of artificial neural networks. (shrink)

In this single-blind within-subject study, autonomic and EEG variables were compared during 10-min, order-balanced eyes-closed rest and Transcendental Meditation (TM) sessions. TM sessions were distinguished by (1) lower breath rates, (2) lower skin conductance levels, (3) higher respiratory sinus arrhythmia levels, and (4) higher alpha anterior-posterior and frontal EEG coherence. Alpha power was not significantly different between conditions. These results were seen in the first minute and were maintained throughout the 10-min sessions. TM practice appears to (1) lead to a (...) state fundamentally different than eyes-closed rest; (2) result in a cascade of events in the central and autonomic nervous systems, leading to a rapid change in state (within a minute) that was maintained throughout the TM session; and (3) be best distinguished from other conditions through autonomic and EEG alpha coherence patterns rather than alpha power. Two neural networks that may mediate these effects are suggested. The rapid shift in physiological functioning within the first minute might be mediated by a ''neural switch'' in prefrontal areas inhibiting activity in specific and nonspecific thalamocortical circuits. The resulting ''restfully alert'' state might be sustained by a basal ganglia-corticothalamic threshold regulation mechanism automatically maintaining lower levels of cortical excitability. (shrink)

Intended to introduce readers to the use of artificial neural networks in the study of music, this volume contains numerous case studies and research findings that address problems related to identifying scales, keys, classifying musical chords, and learning jazz chord progressions. A detailed analysis of networks is provided for each case study which together demonstrate that focusing on the internal structure of trained networks could yield important contributions to the field of music cognition.

The artificial neural network is employed to study children’s psychological emotion recognition to fully reflect the psychological status of preschool children and promote the healthy growth of preschool children. Specifically, the ANN model is used to construct the human physiological signal measurement platform and emotion recognition platform to measure the human physiological signals in different psychological and emotional states. Finally, the parameter values are analyzed on the emotion recognition platform to identify the children’s psychological and emotional states accurately. The (...) experimental results demonstrate that the recognition ability of children aged 4–6 to recognize the three basic emotions of happiness, calm, and fear increases with age. Besides, there are significant age differences in children’s recognition of happiness, calm, and fear. In addition, the effect of 4-year-old children on the theory of mind tasks is less than that of 5- to 6-year-old children, which may be related to more complex cognitive processes. Preschool children are experiencing a stage of rapid emotional development. If children cannot be guided to reasonably identify and deal with emotions at this stage, their education level and social ability development will be significantly affected. Therefore, this study has significant reference value for preschool children’s emotional recognition and guidance and can promote children’s emotional processing and mental health. (shrink)

Heuristics of evolutionary biology dictate that phylogenetically older processes are inherently more stable and resilient to disruption than younger processes. On the grounds that non-declarative behaviour emerged long before declarative behaviour, Reber argues that implicit learning is supported by neural processes that are evolutionarily older than those supporting explicit learning. Reber suggested that implicit learning thus leads to performance that is more robust than explicit learning. Applying this evolutionary framework to motor performance, we examined whether implicit motor learning, relative (...) to explicit motor learning, conferred motor output that was resilient to physiological fatigue and durable over time. In Part One of the study a fatigued state was induced by a double Wingate Anaerobic test protocol. Fatigue had no affect on performance of participants in the implicit condition; whereas, performance of participants in the explicit condition deteriorated significantly. In Part Two of the study a convenience sample of participants was recalled following a one-year hiatus. In both the implicit and the explicit condition retention of performance was seen and, contrary to the findings in Part One, so was resilience to fatigue. The resilient performance in the explicit condition after one year may have resulted from forgetting or from consolidation of declarative knowledge as implicit memories. In either case, implicit processes were left to more effectively support motor performance. (shrink)