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THE EQUATIONS FOR CONSCIOUSNESS: A REPLY TO 'TRACKING THE TRAVELS,' A REVIEW OF JOURNEY OF THE MIND A complete theory of consciousness should explain: How physical activity in biological structures [...]

Elusive as the concept of consciousness is, it surely refers to a most evident fact, which must be 'a substantial part of what psychologists have been examining all along' (Natsoulas, [...], Findings in a number of neuropsychological studies involving reports of decisions to initiate spontaneous movement (e.g., Fried, Mukamel, & Kreiman, 2011; Libet, Gleason, Wright, & Pearl, 1983; Soon, Brass, Heinze, & Haynes, 2008) are often interpreted as putting in question the reality of conscious control and, by extension, the time-honored concept of free will. I suggest that several problems with the basic paradigm used by most such studies, elaborated on in some recent articles (prominently Miller, Shepherdson, & Trevena, 2011, and Schurger, Sitt, & Dehaene, 2012), as well as some other arguments, raise doubt that conscious control is in fact a gratuitous byproduct of preconscious brain activity.

At suprathreshold levels, detection and awareness of visual stimuli are typically synonymous in nonclinical populations. But following postgeniculate lesions, some patients may perform above chance in forced-choice detection paradigms, while reporting not to see the visual events presented within their blind field. This phenomenon, termed 'blindsight,' is intriguing because it demonstrates a dissociation between detection and perception. It is possible, however, for a blindsight patient to have some 'feeling' of the occurrence of an event without seeing per se. This is termed blindsight type II to distinguish it from the type I, defined as discrimination capability in the total absence of any acknowledged awareness. Here we report on a well-studied patient, D.B., whose blindsight capabilities have been previously documented. We have found that D.B. is capable of detecting visual patterns defined by changes in luminance (first-order gratings) and those defined by contrast modulation of textured patterns (textured gratings; second-order stimuli) while being aware of the former but reporting no awareness of the latter. We have systematically investigated the parameters that could lead to visual awareness of the patterns and show that mechanisms underlying the subjective reports of visual awareness rely primarily on low spatial frequency, first-order spatial components of the image. doi/ 10.1073/pnas.1015652107

In the human brain, cognitive-control processes are generally considered distinct from the unconscious mechanisms elicited by subliminal priming. Here, we show that cognitive control engaged in situations of response conflict interacts with the negative (inhibitory) phase of subliminal priming. Thus, cognitive control may surprisingly share common processes with nonconscious brain mechanisms. In contrast, our findings reveal that subliminal inhibition does not, however, interact with control adaptation--the supposed modulation of current control settings by previous experience of conflict. Therefore, although influential models have grouped immediate cognitive control and control adaptation together as products of the same conflict detection and control network, their relationship to subliminal inhibition separates them. Overall, these results suggest that the important distinction lies not between cognitive or top-down processes on the one hand and nonconscious priming mechanisms on the other hand but between responsive (poststimulus) mechanisms that deal with sensorimotor activation after it has occurred and preparatory (prestimulus) mechanisms that are modulated before stimulus arrival. automatic | executive | negative compatibility | voluntary | flanker task doi/ 10.1073/pnas.1001925107

An individual, human or animal, is defined to be in a conscious state empirically by the behavioral ability to respond meaningfully to stimuli, whereas the loss of consciousness is defined by unresponsiveness. PET measurements of glucose or oxygen consumption show a widespread [approximately equal to]45% reduction in cerebral energy consumption with anesthesia-induced loss of consciousness. Because baseline brain energy consumption has been shown by [sup.13]C magnetic resonance spectroscopy to be almost exclusively dedicated to neuronal signaling, we propose that the high level of brain energy is a necessary property of the conscious state. Two additional neuronal properties of the conscious state change with anesthesia. The delocalized fMRI activity patterns in rat brain during sensory stimulation at a higher energy state (close to the awake) collapse to a contralateral somatosensory response at lower energy state (deep anesthesia). Firing rates of an ensemble of neurons in the rat somatosensory cortex shift from the [gamma]-band range (20-40 Hz) at higher energy state to anesthesia | awake | glutamate | neuroimaging | oxygen consumption

Neuroimaging studies of brain-damaged patients diagnosed as in the vegetative state suggest that the patients might be conscious. This might seem to raise no new ethical questions given that in related disputes both sides agree that evidence for consciousness gives strong reason to preserve life. We question this assumption. We clarify the widely held but obscure principle that consciousness is morally significant. It is hard to apply this principle to difficult cases given that philosophers of mind distinguish between a range of notions of consciousness and that is unclear which of these is assumed by the principle. We suggest that the morally relevant notion is that of phenomenal consciousness and then use our analysis to interpret cases of brain damage. We argue that enjoyment of consciousness might actually give stronger moral reasons not to preserve a patient's life and, indeed, that these might be stronger when patients retain significant cognitive function. Keywords: brain-imaging, consciousness, minimally conscious state, termination of treatment, vegetative state

Autoregulation of renal blood flow (RBF) occurs via myogenic and tubuloglomerular feedback (TGF) mechanisms that are engaged by pressure changes within preglomerular arteries and by tubular flow and content, respectively. Our understanding of autoregulatory function in the kidney largely stems from experiments in anesthetized animals where renal perfusion pressure is precisely controlled. However, normally occurring variations in blood pressure are sufficient to engage both myogenic and TGF mechanisms, making the assessment of autoregulatory function in conscious animals of significant value. To our knowledge, no studies have evaluated the dynamics of RBF in conscious mice. Therefore, we used spectral analysis of blood pressure and RBF and identified dynamic operational characteristics of the myogenic and TGF mechanisms in conscious, freely moving mice instrumented with ultrasound flow probes and arterial catheters. The myogenic response generates a distinct resonance peak in transfer gain at 0.31 [+ or -] 0.01 Hz. Myogenic-dependent attenuation of RBF oscillations, indicative of active autoregulation, is apparent as a trough in gain below 0.3 Hz (-6.5 [+ or -] 1.3 dB) and a strong positive phase peak (93 [+ or -] 9 deg), which are abolished by amlodipine infusion. Operation of TGF produces a local maximum in gain at 0.05 [+ or -] 0.01 Hz and a positive phase peak (62.3 [+ or -] 12.3 deg), both of which are eliminated by infusion of furosemide. Administration of amlodipine eliminated both myogenic and TGF signature peaks, whereas furosemide shifted the myogenic phase peak to a slower operational frequency. These data indicate that myogenic and TGF dynamics may be used to investigate the effectiveness of renal autoregulatory mechanisms in conscious mice. myogenic; tubuloglomerular feedback; mouse; renal blood flow; dynamics; conscious

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.

A broad range of evidence regarding the functional organization of the vertebrate brain--spanning from comparative neurology to experimental psychology and neurophysiology to clinical data--is reviewed for its bearing on conceptions of the neural organization of consciousness. A novel principle relating target selection, action selection, and motivation to one another, as a means to optimize integration for action in real time, is introduced. With its help, the principal macrosystems of the vertebrate brain can be seen to form a centralized functional design in which an upper brain stem system organized for conscious function performs a penultimate step in action control. This upper brain stem system retained a key role throughout the evolutionary process by which an expanding forebrain--culminating in the cerebral cortex of mammals--came to serve as a medium for the elaboration of conscious contents. This highly conserved upper brainstem system, which extends from the roof of the midbrain to the basal diencephalon, integrates the massively parallel and distributed information capacity of the cerebral hemispheres into the limited-capacity, sequential mode of operation required for coherent behavior. It maintains special connective relations with cortical territories implicated in attentional and conscious functions, but is not rendered nonfunctional in the absence of cortical input. This helps explain the purposive, goal-directed behavior exhibited by mammals after experimental decortication, as well as the evidence that children born without a cortex are conscious. Taken together these circumstances suggest that brainstem mechanisms are integral to the constitution of the conscious state, and that an adequate account of neural mechanisms of conscious function cannot be confined to the thalamocortical complex alone. Keywords: action selection; anencephaly; central decision making; consciousness; control architectures; hydranencephaly; macrosystems; motivation; target selection; zona incerta

Conscious perception, like the sight of a coffee cup, seems to involve the brain identifying a stimulus. But conscious input activates more brain regions than are needed to identify coffee cups and faces. It spreads beyond sensory cortex to frontoparietal association areas, which do not serve stimulus identification as such. What is the role of those regions? Parietal cortex support the 'first person perspective' on the visual world, unconsciously framing the visual object stream. Some prefrontal areas select and interpret conscious events for executive control. Such functions can be viewed as properties of the subject, rather than the object, of experience--the 'observing self' that appears to be needed to maintain the conscious state.

Consciousness has a number of apparently disparate properties, some of which seem to be highly complex and even inaccessible to outside observation. To place these properties within a biological framework requires a theory based on a set of evolutionary and developmental principles. This paper describes such a theory, which aims to provide a unifying account of conscious phenomena.

Byline: L. I. Aftanas (1), S. A. Golosheikin (1) Abstract: The specific features of the topology of spectral powers and coherent interregional interrelationships in the narrow, individually determined [delta]-, I,-, [alpha].sub.1-, [alpha].sub.2-, and [alpha].sub.3-frequency bands were studied by means of high-resolution EEG (62 channels) in novice and experienced meditators (NMs and EMs) at rest and under the conditions of generation of an altered state of consciousness characterized by inactivation of cognitive activity and the occurrence of a positive emotional experience of happiness. EMs in the meditation-free state were found to be characterized by a shift in the values of the individual [alpha] frequency to a lower-frequency region of the spectrum, along with higher, compared to NMs, I,-, [alpha].sub.1-, [alpha].sub.2-, and [alpha].sub.3-band power values, which probably reflects the cumulative character of the influence of long-term meditative practice. The effective achievement of altered states of consciousness in EMs was associated with an increase in the local I,- and [alpha].sub.1 powers in the anterior cortical areas, as well as long-distance coherence between the prefrontal and posterior associative cortex with the formation of a center of gravity in the left prefrontal region (lead AF .sub.3). According to the data of the correlation analysis of the EEG power values and the data of subjective scaling of the meditation state, the I,-power values were positively associated with positive emotional experiences and negatively associated with the level of mental activity. The results of this study are consistent with current concepts that the I, and [alpha] activities in narrow frequency bands reflect the activity of multifunctional neuronal networks selectively associated with processes of cognitive and affective activity. Author Affiliation: (1) Siberian Division, Russian Academy of Medical Sciences, Institute of Physiology, ul. Timakova 4, Novosibirsk, 630117, Russia Article History: Registration Date: 11/10/2004

Byline: T. G. Beteleva (1), D. A. Farber (1) Abstract: Event-related potentials (ERP) in response to complex target stimuli, which consisted of a central recognizable picture and a lateral masked image (analyzed at the unconscious level) were recorded in adult subjects and seven-year-old children. ERP components N200, N300, and P400/N400 had different topography and were differently pronounced in adults and children. In adult subjects, the N200 component that reflects the processing of a sensory stimulus was recorded in the temporo-parieto-occipital and occipital areas. In children, N200 was recorded in the caudal regions and the frontal areas of the cortex. Analysis of different waveforms obtained by subtraction of the ERP to the central stimulus from the ERP to the complex stimulus showed that unconscious stimulus processing in adult subjects is not reflected in the ERP structure. In children, an unconsciously processed image incorporated into a complex stimulus evokes processing negativity in the occipital and frontal cortical areas. Comparison of ERP in groups of children divided by their reflectivity/impulsivity showed that, predominantly, the left frontal area is involved in image analysis at the unconscious level in reflective children and, predominantly, the right frontal area participates in unconscious image analysis in impulsive children. It is suggested that the perfection of the visual recognition of a target stimulus, which contains additional unconsciously processed information, consists in growth of the involvement of the left-hemispheric mechanisms (with respective growth of significance of the left-hemispheric mechanisms) and in a decrease in the role of the frontal areas in analysis of sensory information. Author Affiliation: (1) Institute of Developmental Physiology, Russian Academy of Education, ul. Pogodinskaya 8-2, Moscow, 119869, Russia Article History: Registration Date: 12/10/2004

If there is a received orthodoxy in contemporary philosophy of mind and cognitive science, it is that all features of the mind, including meaning, action, and consciousness, can and perhaps [...]

Byline: K. V. Sudakov (1) Abstract: Pavlov's concepts of the dynamic stereotype -- 'imprints of reality' -- are developed on the basis of the theory of functional systems. Parameters of reality and especially the results of activity satisfying the leading needs of living organisms are dynamically 'impressed' in the form of molecular engrams in structures of the results-of-actions acceptors involved in the dominant motivation. The dominant motivation plays the leading role in retrieval of previously formed engrams of the results-of-action acceptors in different functional systems. A general theoretical concept of the emotional and verbal forms of consciousness and their close interaction in humans is developed. Author Affiliation: (1) Russian Academy of Medical Sciences, P. K. Anokhin Science Research Institute of Normal Physiology, Moscow Article History: Registration Date: 08/10/2004

Many current neurophysiological, psychophysical, and psychological approaches to vision rest on the idea that when we see, the brain produces an internal representation of the world. The activation of this internal representation is assumed to give rise to the experience of seeing. The problem with this kind of approach is that it leaves unexplained how the existence of such a detailed internal representation might produce visual consciousness. An alternative proposal is made here. We propose that seeing is a way of acting. It is a particular way of exploring the environment. Activity in internal representations does not generate the experience of seeing. The outside world serves as its own, external, representation. The experience of seeing occurs when the organism masters what we call the governing laws of sensorimotor contingency. The advantage of this approach is that it provides a natural and principled way of accounting for visual consciousness, and for the differences in the perceived quality of sensory experience in the different sensory modalities. Several lines of empirical evidence are brought forward in support of the theory, in particular: evidence from experiments in sensorimotor adaptation, visual 'filling in,' visual stability despite eye movements, change blindness, sensory substitution, and color perception. Keywords: action; change blindness; consciousness; experience; perception; qualia; sensation; sensorimotor

WHAT are the social, cultural, and discursive conventions--the etiquette--that surround consciousness and its alterations? "Etiquette" refers generally to the practices and forms, most commonly of behavior, that are prescribed by […]

EVERYONE would claim to be an individual; everyone would claim they were different from everyone else. And yet the macabre idea is that if we all took our brains out, […]

If the emergence of higher order consciousness is produced by transcerebral electromagnetic processes recreated every 20 msec. to 25 msec., then any frequency band in addition to the 40-Hz range could serve as a binding factor for this process. Second order differences or 'derivatives,' obtained by lagging differences in real time between adjacent frequency integers, indicate that 20 msec. to 25 msec. intervals could be continuously recreated by shifts in frequency within approximately 6.3 and 7.8 Hz. Higher order differences indicate that variations within very narrow band widths between 5 Hz and 6 Hz would generate continuous recreations of 20 msec. to 25-msec. intervals.

There are defined hypothalamic functions in the genesis of thirst, but little is known of the cortical processes subserving consciousness of thirst notwithstanding the medical disorders that occur in psychiatric illness, addiction, and the attested decline of thirst with aging. In 10 adult males, positron emission tomography scans were made (i) during genesis of moderate thirst by infusion of i.v. hypertonic saline 0.51 M, (ii) after irrigation of the mouth with water to remove the sensation of dryness, and (iii) 3, 14, 45, and 60 minutes after drinking water to fully satiate thirst. The correlation of regional cerebral blood flow with thirst score showed the major activation to be in the posterior cingulate. Maximum thirst sensation evoked 13 highly significant activations and 9 deactivations in cingulate and parahippocampal gyri, insula, thalamus, amygdala, and mesencephalon. It is possible that cingulate sites (Brodmann's areas 32, 24, and 31) that persisted with wet mouth but disappeared immediately after drinking to satiation may have an important role in the consciousness of thirst. Consciousness of thirst, a primal vegetative emotion, and satiation of thirst appear to be subserved by phylogenetically ancient brain regions. This is salient to current discussion on evolutionary emergence of primary consciousness.

Consciousness involves the internal or organic relationship between social groupings, also known as process. Internal connection between group members is based on the principle of quantum nonlocality or synchronicity. Hierarchies of consciousness have evolved through successive levels of social organization, on the levels of groups of cells, individual organisms, and communities. Thus, all consciousness is collective consciousness. Evolutionary principles of energy utilization indicate that the next level of conscious systems development will be that of collective planetary consciousness. Before this development can occur, the problems of dissociation between individuals must be overcome. This dissociation is brought about by the illusions of separateness and an ego-centered reality. These illusions are dispelled by perception of collective consciousness or collective self consciousness. KEYWORDS: physiology, collective consciousness, consciousness, mind, synchronicity.

There are two concepts of consciousness, access consciousness and phenomenal consciousness. But just as the concepts of water and [H.sub.2]O are different concepts of the same thing, so the two concepts of consciousness might come to the same thing in the brain. Some recent papers by Crick and Koch raise issues that suggest that these two concepts of consciousness might have different (though overlapping) neural correlates, despite Crick and Koch's implicit rejection of this idea.

The main purpose of the present study was to investigate the psychophysiological effects of music on human EEG. For this purpose, a sound modulator was developed which simulates the sound-pressure variations of a given piece of music by white noise (sim-music). Using this apparatus, the author tested the psychophysiological effects of music on human EEG. The electroencephalograms (EEG), electrocardiograms (ECG), and electrooculograms (EOG) of eight normal volunteers were recorded for a total of 21 min., 5 sec. per session for each subject under three sound conditions: silence for 5 min., two types of music (music) or two types of simulated noise (sim-music) for 11 min., 5 sec., followed by silence for another 5 min. Each subject was exposed to a total of 10 music and 10 sim-music conditions. At the low consciousness level (drowsiness, Stage S1), higher delta component power densities were observed with sim-music than with music. Thus, even in the same Stage S1, entire physiological consciousness levels may be higher when listening to music than to sim-music. While listening to music, many subjects reported that they felt pleasantly relaxed or comfortable. However, with the sim-music, they reported feeling unpleasantly weary and sleepy. It seems that the mental set toward two sound conditions differed greatly for many subjects. In Stage S1, the differences in EEG slow components showed that the differences in consciousness had a physiological aspect and indicated differences in mental set toward both sound conditions and mental activity during the listening conditions.

The mammalian neocortex was studied as the origin of consciousness which evolved from mental units designated as psychons. With the evolution of the mammalian species, the mammalian dendrons differentiated for more effective integration of the increased complexity of interacting inputs which in turn react with psychons. This places mammals above reptiles who lack neocortices and as such cannot evolve conscious experiences.

Merker offers a remarkable statement about the neural integration essential to conscious states provided by the mesodiencephalon. The model for triangular interaction between action selection, target selection, and emotion is heuristic. Unifotunately, there is little interest (relatively speaking) in neuroseienee in the mesodiencephalon, and attention is currently heavily directed to the telencephalon. This suggests that there may be less real momentum than commonly assumed towards the Holy Grail of neuroscience, a scientific theory; of mind, despite the major upsurge in interest.

Disregard or primary-process consciousness is endemic in mind science. Most neuriscientists subscribe to ruthless reductionism whereby mental qualities are discarded in preference for neuronal function. Such ideas often lead to envisioning other animals, and all too often other humans, as unfeeling zombies. Merker correctly highlights how the roots of consciousness exist in ancient neural territories we share, remarkably homologously, with all the other vertebrates.

Why is consciousness associated with recovery of memories that are initially dependent on the hippocampal system? A hypothesis is proposed that the medial temporal lobe/hippocampal complex (MTL/H) receives as its input only information that is consciously apprehended. By a process termed 'cohesion,' the MTL/H binds into a memory trace those neural elements that mediated the conscious experience so that effectively, 'consciousness' is an integral part of the memory trace. It is the phenomenological records of events (Conway 1992), integrated consciousness-content packets, that are recovered when memory traces are retrieved.

The Mind Revealed? HAS WOLF SINGER UNCOVERED the cellular basis of consciousness? Some neuroscientists think he may have, although Singer himself stops short of such a bold claim. Last year [...]

The question of whether a fetus can experience pain is an immense challenge. The issue demands consideration of the physical and psychological basis of being and the relation between the two. At the center of this debate is the question of how it is that we are conscious, a question that has inspired the writing of some of our most brilliant contemporary philosophers and scientists, with one commentary suggesting surrender. In my earlier review I attempted to draw together the various strands of thinking that had attacked the question of fetal pain and relate them back to the bigger question of consciousness. In their vituperative response, Benatar and Benatar bite off my finger before looking to where I am pointing. I will examine each of their criticisms

The limited capacity of immediate memory 'rides' on the even more limited capacity of consciousness, which reflects the dynamic activity of the thalamocortical core of the brain. Recent views of the conscious narrow-capacity component of the brain are explored with reference to global workspace theory (Baars 1988; 1993; 1998). The radical limits of immediate memory must be explained in terms of biocognitive brain architecture.

Solms and the other authors in this series of BBS target articles accept the findings that the executive control of the REM/NREM cycle is still localized within a narrow region of the pontine brainstem. However, recent findings challenge this notion. We will review the recent data and suggest instead that the hypothalamus is the primary regulator of states of consciousness. If the hypothalamus indeed controls all the fun stuff, such as sex, eating, drinking, sleeping, and so on, then one can more easily accept Solms's argument that dreams are also generated from the forebrain. [SOLMS]