Block argues that relevant data in psychology and neuroscience shows that access consciousness is not constitutively necessary for phenomenality. However, a phenomenal state can be access conscious in two radically different ways. Its content can be access conscious, or its phenomenality can be access conscious. I’ll argue that while Block’s thesis is right when it is formulated in terms of the first notion of access consciousness, there is an alternative hypothesis about the relationship between phenomenality and access in terms of (...) the second notion that is not touched by Block’s argument. (shrink)

Evolution leads to more and more complex structures, e.g., molecules, cells and organisms. By means of such structures elementary dynamic bio-electrical fields originate in single cells. They further develop into neurons with neuronal fields, and these combine and integrate in brains into global neuro-electrical fields (NEF) as a medium for the fast representation of outer stimuli. The present hypothesis proposes a specific state of the global NEF in brains as the signature of consciousness. This NEF changes periodically between two states, (...) a de- and a hyperpolarized brain state, and these in turn are paralleled intimately by transitions between consciousness and unconsciousness. In the hyperpolarized state the elementary neuronal fields are enslaved and synchronized by strong oscillations, and under these conditions the NEF is of low information capacity. In the depolarized state, however, the elementary fields are freed to self-organize and superimpose into an integrated NEF rich in information. In this condition the NEF acquires a qualitatively new state variable: consciousness. This new variable is no longer physically measurable; it can only be perceived by introspection. (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)

The papers in this special issue are all descended from papers presented at the second Online Consciousness Conference. I founded the Online Consciousness Conference at Consciousness Online (http://consciousnessonline.wordpress.com) in 2008 mostly because no one else would. Being inspired by the Online Philosophy Conference, I mentioned to several people that it would be great if we had something like that in Consciousness Studies. People I talked to were very enthusiastic but no one seemed like they wanted to initiate the process. I (...) figured I would give it a shot and have been pleasantly surprised by the results. Papers from the first conference were published in a special issue of the Journal of Consciousness Studies, papers from the second are in this special issue, and papers from the third conference (2011) are due to come out as a book in Springer’s series Studies in Brain and Mind. As I write this I am planning the fourth conference for February 2012. There is no way I could have known back in 2008 how well the conference would be received but I am grateful for that reception. (shrink)

Philosophers have been talking about brain states for almost 50 years and as of yet no one has articulated a theoretical account of what one is. In fact this issue has received almost no attention and cognitive scientists still use meaningless phrases like 'C-fiber firing' and 'neuronal activity' when theorizing about the relation of the mind to the brain. To date when theorists do discuss brain states they usually do so in the context of making some other argument with the (...) result being that any discussion of what brain states are has a distinct en passant flavor. In light of this it is a goal of mine to make brain states the center of attention by providing some general discussion of them. I briefly look at the argument of Bechtel and Mundale, as I think that they expose a common misconception philosophers had about brain states early on. I then turn to briefly examining Polger's argument, as I think he offers an intuitive account of what we expect brain states to be as well as a convincing argument against a common candidate for knowledge about brain states that is currently "on the scene." I then introduce a distinction between brain states and states of the brain: Particular brain states occur against background states of the brain. I argue that brain states are patterns of synchronous neural firing, which reflects the electrical face of the brain; states of the brain are the gating and modulating of neural activity and reflect the chemical face of the brain. (shrink)

The neuroanatomical substrates controlling and regulating sleeping and waking, and thus consciousness, are located in the brain stem. Most crucial for bringing the brain into a state conducive for consciousness and information processing is the mesencephalic part of the brain stem. This part controls the state of waking, which is generally associated with a high degree of consciousness. Wakefulness is accompanied by a low-amplitude, high-frequency electroencephalogram, due to the fact that thalamocortical neurons fire in a state of tonic depolarization. Information (...) can easily pass the low-level threshold of these neurons, leading to a high transfer ratio. The complexity of the electroencephalogram during conscious waking is high, as expressed in a high correlation dimension. Accordingly, the level of information processing is high. Spindles, and alpha waves in humans, mark the transition from wakefulness to sleep. These phenomena are related to drowsiness, associated with a reduction in consciousness. Drowsiness occurs when cells undergo moderate hyperpolarizations. Increased inhibitions result in a reduction of afferent information, with a lowered transfer ratio. Information processing subsides, which is also expressed in a diminished correlation dimension. Consciousness is further decreased at the onset of slow wave sleep. This sleep is controlled by the medullar reticular formation and is characterized by a high-voltage, low-frequency electroencephalogram. Slow wave sleep becomes manifest when neurons undergo a further hyperpolarization. Inhibitory activities are so strong that the transfer ratio further drops, as does the correlation dimension. Thus, sensory information is largely blocked and information processing is on a low level. Finally, rapid eye movement sleep is regulated by the pontine reticular formation and is associated with a ''wake-like'' electroencephalographic pattern. Just as during wakefulness, this is the expression of a depolarization of thalamocortical neurons. The transfer ratio of rapid eye movement sleep has not yet been determined, but seems to vary. Evidence exists that this type of sleep, associated with dreaming, with some kind of perception and consciousness, is involved in processing of ''internal'' information. In line with this, rapid eye movement sleep has higher correlation dimensions than slow-wave sleep and sometimes even higher than wakefulness. It is assumed that the ''near-the-threshold'' depolarized state of neurons in the thalamus and cerebral cortex is a necessary condition for perceptual processes and consciousness, such as occurs during waking and in an altered form during rapid eye movement sleep. (shrink)

Merker's core idea, that the experience of being conscious reflects the interactions of actions, targets, and motivations in the upper brainstem, with cortex providing the content of the conscious experience, merits serious consideration. However, we have two areas of concern: first, that his definition of consciousness is so broad that it is difficult to find any organisms with a brain that could be non-conscious; second, that the focus on one cortical–subcortical system neglects other systems (e.g., basal forebrain and brainstem cholinergic (...) systems and their cortical and thalamic target areas) which may be of at least equal significance. (Published Online May 1 2007). (shrink)

In Sisyphus's Boulder, Eric Dietrich and Valerie Hardcastle argue that we will never get such a theory because consciousness has an essential property that...

To figure out whether the main empirical question “Is our brain hardwired to believe in and produce God, or is our brain hardwired to perceive and experience God?” is answered, this paper presents systematic critical review of the positions, arguments and controversies of each side of the neuroscientific-theological debate and puts forward an integral view where the human is seen as a psycho-somatic entity consisting of the multiple levels and dimensions of human existence (physical, biological, psychological, and spiritual reality), allowing (...) consciousness/mind/spirit and brain/body/matter to be seen as different sides of the same phenomenon, neither reducible to each other. The emergence of a form of causation distinctive from physics where mental/conscious agency (a) is neither identical with nor reducible to brain processes and (b) does exert “downward” causal influence on brain plasticity and the various levels of brain functioning is discussed. This manuscript also discusses the role of cognitive processes in religious experience and outlines what can neuroscience offer for study of religious experience and what is the significance of this study for neuroscience, clinicians, theology and philosophy. A methodological shift from “explanation” to “description” of religious experience is suggested. This paper contributes to the ongoing discussion between theologians, cognitive psychologists and neuroscientists. (shrink)

Objective: The value of spontaneous EEG oscillations in distinguishing patients in vegetative and minimally conscious states was studied. Methods: We quantified dynamic repertoire of EEG oscillations in resting condition with closed eyes in patients in vegetative and minimally conscious states (VS and MCS). The exact composition of EEG oscillations was assessed by the probability-classification analysis of short-term EEG spectral patterns. Results: The probability of delta, theta and slow-alpha oscillations occurrence was smaller for patients in MCS than for VS. Additionally, only (...) patients in MCS demonstrated fast-alpha oscillation occurrence. Depending on the type and composition of EEG oscillations, the probability of their occurrence was either aetiology dependent or independent. The probability of EEG oscillations occurrence differentiated brain injuries with different aetiologies. Conclusions: Spontaneous EEG oscillations have a potential value in distinguishing patients in VS and MCS. Significance: This work may have implications for clinical care, rehabilitative programs and medical–legal decisions in patients with impaired consciousness states following coma due to acute brain injuries. (shrink)

This paper briefly review a current trend in neuroscience aiming to combine neurophysiological and physical concepts in order to understand the emergence of spatio-temporal patterns within brain activity by which brain constructs knowledge from multiple streams of information. The authors further suggest that the meanings, which subjectively are experienced as thoughts or perceptions can best be described objectively as created and carried by large fields of neural activity within the operational architectonics of brain functioning.

The target paper of Dr. Feinberg is a testimony to an admirable scholarship and deep thoughtfulness. This paper develops a general theoretical framework of nested hierarchy in the brain that allows production of mind with consciousness. The difference between non-nested and nested hierarchies is the following. In a non-nested hierarchy the entities at higher levels of the hierarchy are physically independent from the entities at lower levels and there is strong constraint of higher upon lower levels. In a nested hierarchy, (...) higher levels are physically composed of lower levels, and there is no central control of the system resulting in weak constraint of higher upon lower levels. (shrink)

The understanding of the interrelationship between brain and mind remains far from clear. It is well established that the brain's capacity to integrate information from numerous sources forms the basis for cognitive abilities. However, the core unresolved question is how information about the "objective" physical entities of the external world can be integrated, and how unifiedand coherent mental states (or Gestalts) can be established in the internal entities of distributed neuronal systems. The present paper offers a unified methodological and conceptual (...) basis for a possible mechanism of how the transient synchronization of brain operations may construct the unified and relatively stable neural states, which underlie mental states. It was shown that the sequence of metastable spatial EEG mosaics does exist and probably reflects the rapid stabilization periods of the interrelation of large neuron systems. At the EEG level this is reflected in the stabilization of quasi-stationary segments on corresponding channels. Within the introduced framework, physical brain processes and psychological processes are considered as two basic aspects of a single whole informational brain state. The relations between operational process of the brain, mental states and consciousness are discussed. (shrink)

Background: Patients in a vegetative state pose problems in diagnosis, prognosis and treatment. Currently, no prognostic markers predict the chance of recovery, which has serious consequences, especially in end-of-life decision-making. -/- Objective: We aimed to assess an objective measurement of prognosis using advanced electroencephalography (EEG). -/- Methods: EEG data (19 channels) were collected in 14 patients who were diagnosed to be persistently vegetative based on repeated clinical evaluations at 3 months following brain damage. EEG structure parameters (amplitude, duration and variability (...) within quasi-stationary segments, as well as the spatial synchrony between such segments and the strength of this synchrony) were used to predict recovery of consciousness 3 months later. -/- Results: The number and strength of cortical functional connections between EEG segments were higher in patients who recovered consciousness (P < .05 – P < .001) compared with those who did not recover. Linear regression analysis confirms that EEG structure parameters are capable of predicting (P = .0025) recovery of consciousness 6 months post-injury, whereas the same analysis failed to significantly predict patient outcome based on aspects of their clinical history alone (P = .629) or conventional EEG spectrum power (P = .473). -/- Conclusions: The result of this preliminary study demonstrates that structural strategy of EEG analysis is better suited for providing prognosis of consciousness recovery than existing methods of clinical assessment and of conventional EEG. Our results may be a starting point for developing reliable prognosticators in patients who are in vegetative state, with the potential to improve their day-to-day management, quality of life, and access to early interventions. (shrink)

Although several studies propose that the integrity of neuronal assemblies may underlie a phenomenon referred to as awareness, none of the known studies have explicitly investigated dynamics and functional interactions among neuronal assemblies as a function of consciousness expression. In order to address this question EEG operational architectonics analysis (Fingelkurts and Fingelkurts, 2001, 2008) was conducted in patients in minimally conscious (MCS) and vegetative states (VS) to study the dynamics of neuronal assemblies and operational synchrony among them as a function (...) of consciousness expression. We found that in minimally conscious patients and especially in vegetative patients neuronal assemblies got smaller, their life-span shortened and they became highly unstable. Furthermore, we demonstrated that the extent/volume and strength of operational synchrony among neuronal assemblies was smallest or even absent in VS patients, intermediate in MCS patients and highest in healthy fully-conscious subjects. All findings were similarly observed in EEG alpha as well as beta1 and beta2 frequency oscillations. The presented results support the basic tenets of Operational Architectonics theory of brain-mind functioning and suggest that EEG operational architectonics analysis may provide an objective and accurate means of assessing signs of (un)consciousness in patients with severe brain injuries. Therefore this methodological approach may complement the existing “gold standard” of behavioral assessment of this population of challenging patients and inform the diagnostic and treatment decision-making processes. (shrink)

The default mode network (DMN) has been consistently activated across a wide variety of self-related tasks, leading to a proposal of the DMN’s role in self-related processing. Indeed, there is limited fMRI evidence that the functional connectivity within the DMN may underlie a phenomenon referred to as self-awareness. At the same time, none of the known studies have explicitly investigated neuronal functional interactions among brain areas that comprise the DMN as a function of self-consciousness loss. To fill this gap, EEG (...) operational synchrony analysis was performed in patients with severe brain injuries in vegetative and minimally conscious states to study the strength of DMN operational synchrony as a function of self-consciousness expression. We demonstrated that the strength of DMN EEG operational synchrony was smallest or even absent in patients in vegetative state, intermediate in patients in minimally conscious state and highest in healthy fully self-conscious subjects. At the same time the process of decoupling of operations performed by neuronal assemblies that comprise the DMN was highest in patients in vegetative state, intermediate in patients in minimally conscious state and minimal in healthy fully self-conscious subjects. The DMN’s frontal EEG operational module had the strongest decrease in operational synchrony strength as a function of selfconsciousness loss, when compared with the DMN’s posterior modules. Based on these results it is suggested that the strength of DMN functional connectivity could mediate the strength of self-consciousness expression. The observed alterations similarly occurred across EEG alpha, beta1 and beta2 frequency oscillations. Presented results suggest that the EEG operational synchrony within DMN may provide an objective and accurate measure for the assessment of signs of self-(un)consciousness in these challenging patient populations. This method therefore, may complement the current diagnostic procedures for patients with severe brain injuries and, hence, the planning of a rational rehabilitation intervention. (shrink)

In our contribution we will observe phenomenal architecture of a mind and operational architectonics of the brain and will show their intimate connectedness within a single integrated metastable continuum. The notion of operation of different complexity is the fundamental and central one in bridging the gap between brain and mind: it is precisely by means of this notion that it is possible to identify what at the same time belongs to the phenomenal conscious level and to the neurophysiological level of (...) brain activity organization, and what mediates between them. Implications for linguistic semantics, self-organized distributed computing algorithms, artificial machine consciousness, and diagnosis of dynamic brain diseases will be discussed briefly. (shrink)

“Decortication” does not distinguish between removing all cerebral cortex, including three-layered allocortex or just six-layered neocortex. Functional decortication, by spreading depression, reversibly suppresses only neocortex, leaving minimal intentionality. Removal of all forebrain structures except a hypothalamic “island” blocks all intentional behaviors, leaving only tropisms. To what extent do Merker's examples retain allocortex, and how might such residues affect his interpretations? (Published Online May 1 2007).

The majority of the chapters in this edition of The Cognitive Neurosciences are new, and those from the first edition have been completely rewritten and updated ...

CHAPTER A Phenomenological Introduction to the Cognitive Neuroscience of Consciousness Peter G. Grossenbacher National Institute of Mental Health What is ...

According to higher-order theories of consciousness, a mental state is conscious only when represented by another mental state. Higher-order theories must predict there to be some brain areas (or networks of areas) such that, because they produce (the right kind of) higher-order states, the disabling of them brings about deficits in consciousness. It is commonly thought that the prefrontal cortex produces these kinds of higher-order states. In this paper, I first argue that this is likely correct, meaning that, if some (...) higher-order theory is true, prefrontal lesions should produce dramatic deficits in visual consciousness. I then survey prefrontal lesion data, looking for evidence of such deficits. I argue that no such deficits are to be found, and that this presents a compelling case against higher-order theories. (shrink)

In the first part of this commentary I argue that a neurophenomenological analysis of color reveals additional asymmetries that preclude undetectable color transformations, without appealing to weak arguments based on Basic Color Categories (BCCs); that is, I suggest additional factors that must be included in “an empirically accurate model of color experience,” and which break the remaining asymmetries. In the second part I discuss the “isomorphism constraint” and the extent to which we may predict the subjective quality of experience from (...) its neurological correlates. Protophenomena are discussed as a way of capturing in a relational structure all of qualitative experience except for the bare fact of subjectivity. (shrink)

Participants were required to switch among randomly ordered tasks, and instructional cues were used to indicate which task to execute. In Experiments 1 and 2, the participants indicated their readiness for the task switch before they received the target stimulus; thus, each trial was associated with two primary dependent measures: (1) readiness time and (2) target reaction time. Slow readiness responses and instructions emphasizing high readiness were paradoxically accompanied by slow target reaction time. Moreover, the effect of task switching on (...) readiness time was an order of magnitude smaller then the (objectively estimated) duration required for task preparation (Experiment 3). The results strongly suggest that participants have little conscious awareness of their preparedness and challenge commonly accepted assumptions concerning the role of consciousness in cognitive control. (shrink)

My response addresses general commentary themes such as my neglect of the forebrain contribution to human consciousness, the bearing of blindsight on consciousness theory, the definition of wakefulness, the significance of emotion and pain perception for consciousness theory, and concerns regarding remnant cortex in children with hydranencephaly. Further specific topics, such as phenomenal and phylogenetic aspects of mesodiencephalic-thalamocortical relations, are also discussed. (Published Online May 1 2007).

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

conscious content like ``the self in the act of In 1989 the philosopher Colin McGinn asked the knowing'' (see, e.g., chapters 7 and 20 in this following question: ``How can technicolor phe- volume) or high-level phenomenal properties like nomenology arise from soggy gray matter?'' ``coherence'' or ``holism'' (e.g., chapters 8 and 9 (1989: 349). Since then many authors in the ®eld in this volume). But what, precisely, does it mean of consciousness research have quoted this ques- that conscious experience has (...) a ``content''? Is tion over and over, like a slogan that in a nut- this an entity open to empirical research pro- shell conveys a deep and important theoretical grams and interdisciplinary cooperation? And problem. It seems that almost none of them dis- what would it mean to map this content onto covered the subtle trap inherent in this question. physical states ``under a certain description''? In The brain is not gray. The brain is colorless. other words: What kinds of relations a. (shrink)

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

From the assumption that the presence of consciousness is detectable, in the first instance, only from behavioral indicators, I offer a proof to the effect that, with respect to any theory T that states that some particular state or process is the neural correlate of consciousness, there are always rival neural correlates that, from T’s perspective, can never be empirically ruled out. That's because, with respect to these states, the means of detecting consciousness is disrupted along with the empirical test. (...) Possible responses are discussed. (shrink)

To further illuminate the nature of conscious states, it may be progressive to integrate Merker's important contribution with what is known regarding (a) the temporal relation between conscious states and activation of the mesodiencephalic system; (b) the nature of the information (e.g., perceptual vs. premotor) involved in conscious integration; and (c) the neural correlates of olfactory consciousness. (Published Online May 1 2007).

Moutoussis, K., A. Maier, S. Zeki and N. K. Logothetis: Seeing invisible motion: responses of area V5 neurons in the awake-behaving macaque. Soc. for Neurosci. Abstr. 390.11, 1 (11 2005) Abstract.

Human brains exhibit complex dynamic behaviour measured by external recordings of electric (EEG) and magnetic fields (MEG). These data reveal synaptic field oscillations in neocortex at millisecond temporal and centimetre spatial scales. We suggest that the neural networks underlying behaviour and cognition may be viewed as embedded in these synaptic action fields, analogous to social networks embedded in a culture. These synaptic fields may facilitate the binding of disparate networks to produce a behaviour and consciousness that appears unified to external (...) observers. EEG, MEG, anatomy, physiology, and complex physical systems are considered here to suggest fundamental physical and biological properties of human brains that may be required for human consciousness to occur. We do not claim that these tissue properties are necessarily causal; however, they appear to be strongly correlated with human consciousness. Emphasis is placed on the hierarchical structure of brains, non-local connections between distant cortical regions, and resonant interactions between networks. While several of these ideas are supported by both experimental data and mathematical theory, the mathematics is replaced by metaphor for this paper. One conjecture is that the schizophrenias and other diseases occur when neural networks fail to conform to global synaptic fields. Perhaps consciousness is a resonance phenomenon and only properly tuned brains can orchestrate the beautiful music of sentience. (shrink)

CHAPTER Issues in neural basis of consciousness An introduction Naoyuki Osaka Kyoto University, Japan Consciousness is a most important issue for human ...

CHAPTER 1 Neurotransmitter networks Elaine Perry and Allan Young i. Introduction This first chapter sets the scene for subsequent exploration of potential ...

Based on theoretical considerations of Aurell (1979) and Block (1995), we argue that object recognition awareness is distinct from purely sensory awareness and that the former is mediated by neuronal activities in areas that are separate and distinct from cortical sensory areas. We propose that two of the principal functions of neuronal activities in sensory cortex, which are to provide sensory awareness and to effect the computations that are necessary for object recognition, are dissociated. We provide examples of how this (...) dissociation might be achieved and argue that the components of the neuronal activities which carry the computations do not directly enter the awareness of the subject. The results of these computations are sparse representations (i.e., vector or distributed codes) which are activated by the presentation of particular sensory objects and are essentially engrams for the recognition of objects. These final representations occur in the highest order areas of sensory cortex; in the visual analyzer, the areas include the anterior part of the inferior temporal cortex and the perirhinal cortex. We propose, based on lesion and connectional data, that the two areas in which activities provide recognition awareness are the temporopolar cortex and the medial orbitofrontal cortex. Activities in the temporopolar cortex provide the recognition awareness of objects learned in the remote past (consolidated object recognition), and those in the medial orbitofrontal cortex provide the recognition awareness of objects learned in the recent past. The activation of the sparse representation for a particular sensory object in turn activates neurons in one or both of these regions of cortex, and it is the activities of these neurons that provide the awareness of recognition of the object in question. The neural circuitry involved in the activation of these representations is discussed. (shrink)

The neural and endocrine bases of the generation of thirst are reviewed. Based on this review, a hierarchical system of neural structures that regulate water conservation and acquisition is proposed. The system includes primary sensory-receptive areas; secondary sensory structures (circumventricular organs), which detect levels of hormones, including angiotensin II and vasopressin, which are involved in generating thirst; preoptic and hypothalamic structures; and an area within the ventrolateral quadrant of the periaqueductal gray matter. Hodological and other data are used to determine (...) the hierarchical organization of the system. Based on studies of the effects of lesions to various structures within the hierarchy of the system, it is proposed that the awareness of thirst in rodents is either entirely or predominantly due to neuronal activities in a subsection of the ventrolateral periaqueductal gray matter. It is also hypothesized that the awareness of thirst in primates is due to neuronal activities in both the ventrolateral periaqueductal gray and in a region within the medial prefrontal and anterior cingulate cortex. (shrink)

Utilitarianism, the ethical doctrine that holds in its most basic form that right actions are those that maximize pleasure and minimize pain, has been at the center of many of the ethical debates around animal welfare. The most well-known utilitarian of our time, Peter Singer, is widely credited with having sparked the animal welfare movement of the past 35+ years, using utilitarian reasoning to argue against using animals in invasive research that we aren’t willing to perform on humans. Yet many (...) people who have argued for the use of animals in invasive experimentation have also appealed to utilitarian ideas by claiming that insofar as lab animals suffer, the suffering is justified by greater benefits produced via the knowledge gained from research. In this paper, I will examine whether the classical utilitarian prescriptions “maximize pleasure” and “minimize pain” should be treated as equals by the theory and, if not, what the possible implications are for research involving nonhuman animals. -/- The idea that pain has a stronger influence than pleasure is accepted in much of the recent psychology literature on well-being. Some philosophers have also argued that minimizing suffering should play a more important role in ethical theorizing than maximizing pleasure. However, I will argue that neuroscience is uniquely positioned to provide definitive evidence that pleasure and pain are not merely two symmetrical poles of a single scale of experience, but in fact two different types of experiences altogether with dramatically different contributions to our wellbeing. I consider several different conceptions of symmetry, and argue that each is at odds with the most recent empirical results. (shrink)

Recent scientific work aiming to give a neurobiological explanation of phenomenal consciousness has largely focused on finding neural correlates of consciousness (NCC). The hope is that by locating neural correlates of phenomenally conscious mental states, some light will be cast on how the brain is able to give rise to such states. In this paper I argue that NCC research is unable to produce evidence of such neural correlates. I do this by considering two alternative interpretations of NCC research—an eliminativist (...) and a disjunctivist interpretation. I show that each of these interpretations is compatible with the scientific data and yet is more parsimonious than accounts involving the supposed phenomenon of phenomenal consciousness. (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)

The Cambridge Handbook of Consciousness is the first of its kind in the field, and its appearance marks a unique time in the history of intellectual inquiry on the topic. After decades during which consciousness was considered beyond the scope of legitimate scientific investigation, consciousness re-emerged as a popular focus of research towards the end of the last century, and it has remained so for nearly 20 years. There are now so many different lines of investigation on consciousness that the (...) time has come when the field may finally benefit from a book that pulls them together and, by juxtaposing them, provides a comprehensive survey of this exciting field. An authoritative desk reference , which will also be suitable as an advanced textbook. (shrink)