Revonsuo - Inner Presence
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Revonsuo; Inner Presence 16 Conceptualize consciousness as the phenomenal level of organization in the brain.
Revonsuo; Inner Presence 95 Neural basis of consciousness is realized during REM sleep. 79
Revonsuo; Inner Presence 95 Synchronous gamma-band oscillations have been shown to correlate with consciousness in humans and animals. 0
Revonsuo; Inner Presence 96 Synchronized gamma rhythms have been recorded over the neocortex during waking and REM sleep by using magnetoencephalography. 1
Revonsuo; Inner Presence 96 Gamma-band synchronous oscillations are associated with the realization of the phenomenal level in the awake state. 0
Revonsuo; Inner Presence 99 Metaphors of Consciousness 3
Revonsuo; Inner Presence 99 At a stage of scientific research when there is no well-developed theory available of the phenomenon to be explained, the explanations are often described in terms of a suitable metaphor. 0
Revonsuo; Inner Presence 99 A fruitful metaphor captures the essential features of a phenomenon in a single, captivating picture. 0
Revonsuo; Inner Presence 99 A famous metaphor in physics is Bohr's model of the internal structure of the atom. The atom was compared to the solar system where several planets (electrons) orbit around the sun (the nucleus). 0
Revonsuo; Inner Presence 105 The representation of the world in dreams is so amazingly realistic that it is fully justified to call it a "reality." 6
Revonsuo; Inner Presence 105 In both wakefulness and in dreaming we have similar representations of a "world" or a "reality." 0
Revonsuo; Inner Presence 106 Consciousness at the phenomenal level is engaged in internal "world simulation." 1
Revonsuo; Inner Presence 109 "World-Simulation" Metaphor of Consciousness 3
Revonsuo; Inner Presence 109 The "world simulation" metaphor captures consciousness from the first-person point of view -- the way we subjectively experience it. 0
Revonsuo; Inner Presence 111 Consciousness at the phenomenal level is described as self-in-world, full immersion or presence as the you-are-there experience. 2
Revonsuo; Inner Presence 119 World-simulation metaphor of consciousness 8
Revonsuo; Inner Presence 181 The phenomenal contents of consciousness make up a world of subjective experience -- a world simulation. 62
Revonsuo; Inner Presence 181 Throughout our waking and dreaming lives, we find ourselves in the center of a phenomenal world simulation. 0
Revonsuo; Inner Presence 181 Consciousness involves a hierarchical structure -- first comes phenomenal space, then qualities in this space, then organized bundles of qualities, then meaningful bundles of qualities. 0
Revonsuo; Inner Presence 181 Visual shape is the presence of an organized pattern of qualitative features in a phenomenal coordinate system. 0
Revonsuo; Inner Presence 182 The phenomenal world is largely constituted by multitude of organized patterns of qualities. 1
Revonsuo; Inner Presence 192 Virtual Objects As Gestalt Windows and Semantic Windows 10
Revonsuo; Inner Presence 192 Phenomenal features of an object and its overall gestalt. 0
Revonsuo; Inner Presence 193 Hierarchical Organization of the Virtual World 1
Revonsuo; Inner Presence 193 Virtual world consists of the following hierarchy -- phenomenal space, qualities, patterns of qualities, virtual objects (gestalt windows and semantic windows), virtual place, and map location. 0
Revonsuo; Inner Presence 197 Binding and the Phenomenal Unity of Consciousness 4
Revonsuo; Inner Presence 197 One of the most conspicuous features of consciousness is its unity. 0
Revonsuo; Inner Presence 197 The binding problem is the difficulty in seeing how any brain mechanisms could account for the phenomenal unity of consciousness. 0
Revonsuo; Inner Presence 207 Binding and Phenomenal Disunity I -- What Visual Disorders Tell Us about Consciousness 10
Revonsuo; Inner Presence 207 Gestalt psychologists discovered several "laws" or principles that the visual system uses to organize the content of visual awareness. 0
Revonsuo; Inner Presence 207 Visual perception groups basic elements in the phenomenal visual field in such a way that those elements are experienced as perceptual units that naturally belong together. 0
Revonsuo; Inner Presence 208 As a result of the principles of perceptual organization, we are in our conscious visual perception surrounded by a world of coherent bundles of qualitative features: virtual objects (Gestalt windows). 1
Revonsuo; Inner Presence 208 Patients suffering from apperceptive agnosia have widespread brain damage in the occipital cortex and surrounding regions;    a typical cause of the damage is carbon monoxide poisoning. 0
Revonsuo; Inner Presence 227 Binding and Phenomenal Disunity II -- Objects in Space 19
Revonsuo; Inner Presence 227 As we serially scan our surroundings, not only do the elementary features of objects become bound into coherent entities, but we instantaneously know what kinds of objects are present.     A separate object activates    a coherent network    of semantic knowledge. 0
Revonsuo; Inner Presence 227 We not only see a coherent bundle of features ("Gestalt window"), we see it as a representative of a specific category of objects ("semantic window"). 0
Revonsuo; Inner Presence 228 To transform a Gestalt window to a meaningful virtual object requires semantic-conceptual binding. 1
Revonsuo; Inner Presence 228 Location Binding and the Space around Us 0
Revonsuo; Inner Presence 229 We not only immediately see the shape and identity of an object, we are also aware of its position in relation to our body and to other objects in the scene.  This is a location binding. 1
Revonsuo; Inner Presence 235 Split-Brain Patients 6
Revonsuo; Inner Presence 239 Binding in Dreams 4
Revonsuo; Inner Presence 239 Binding and Dream Bizarreness 0
Revonsuo; Inner Presence 239 In the dream world we often experience unusual combinations of perceptual features forming novel, creative, even absolutely crazy or nonsensical wholes. 0
Revonsuo; Inner Presence 239 Dream experiences reveal how binding mechanisms in the brain go awry during sleep. 0
Revonsuo; Inner Presence 242 Failures of Semantic-Conceptual Binding in Dreams 3
Revonsuo; Inner Presence 246 Mechanisms of Bizarreness in Dreams 4
Revonsuo; Inner Presence 252 Dreaming brain reveals how the phenomenal level is put together even in the absence of sensory input. 6
Revonsuo; Inner Presence 252 In the dreaming brain, phenomenal features are bound to locations in simulated space; object parts are bound together to construct integrated simulated objects; objects and persons are recognized and identified as particular objects and persons; they are temporally continuous and embedded in the overall spatial context of the phenomenal world. 0
Revonsuo; Inner Presence 253 Specialized modules produce the Gestalt windows, the of phenomenal surrogates of objects, almost flawlessly. 1
Revonsuo; Inner Presence 253 Dreaming shows a high level of organization and may serve important functions.  The physiologically normal state of dreaming may be indispensable in trying to understand how the brain puts together the inner simulated reality -- the phenomenal level of organization in the brain. 0
Revonsuo; Inner Presence 255 Cognitive Mechanisms of Phenomenal Unity 2
Revonsuo; Inner Presence 259 Consciousness and Attention 4
Revonsuo; Inner Presence 259 In cognitive science, attention has been the concept that comes closest to consciousness. 0
Revonsuo; Inner Presence 259 Often "attention," "awareness," and "consciousness" are treated as referring to more or less the same thing, although their precise relation is rarely explicated. 0
Revonsuo; Inner Presence 259 Attention is a necessary prerequisite of consciousness. 0
Revonsuo; Inner Presence 259 The contents of consciousness equal to or fully determined by the contents of selective attention. 0
Revonsuo; Inner Presence 265 Phenomenal Vision outside the Attentional Spotlight 6
Revonsuo; Inner Presence 265 The world simulation metaphor claims that visual phenomenology also exist outside of the focus of attention, and before attentional selection takes place. 0
Revonsuo; Inner Presence 266 Our subjective phenomenal visual field is structured through attention into two parts -- the region of focal awareness and the surrounding regions of the peripheral awareness. 1
Revonsuo; Inner Presence 266 A paradigm example of phenomenal experience outside attention are the regions of the visual field where attention has not yet focused -- call them regions of preattentive vision. 0
Revonsuo; Inner Presence 266 The preattentive scene is merely a collection of unrecognized objects and a rough spatial layout. 0
Revonsuo; Inner Presence 266 Attention moves across the field of preattentive visual stuff, selecting among the loose bundles of candidate objects, choosing one to enter the focus of attention. 0
Revonsuo; Inner Presence 266 When the focus of attention settles on one object, it becomes a coherent virtual or phenomenal object that can be recognized (i.e. that can open a semantic window). 0
Revonsuo; Inner Presence 266 When the focus of attention    departs from a virtual object,    it falls apart again,    rapidly receding back to the state where it was before attention arrived.     It becomes again just a bundle    of loosely related features    without any global shape. 0
Revonsuo; Inner Presence 267 A virtual, phenomenal object is instantaneously reconstructed from a few pieces of disorganized visual phenomenal stuff.  But the life of an organized virtual object is short. As soon as the spotlight of attention departs, the virtual object a shattered into pieces once more.  But in some other place in which the focus of attention has moved, another virtual object is being created for its short-lived existence. 1
Revonsuo; Inner Presence 267 Attention seems to be necessary only for visual awareness of coherent objects,    but outside focal attention, there is a whole field of phenomenal visual background, full of phenomenal visual stuff that is not organized into coherent visual objects. 0
Revonsuo; Inner Presence 268 There is a constant interplay between the preattentive phenomenal background,    selective attention    and the focus of consciousness,    and the coherently bound visual information transferred to reflective consciousness. 1
Revonsuo; Inner Presence 268 Incoherent bundles of preattentive features    can be experienced only as vague parts of the phenomenal background,    before being attended. 0
Revonsuo; Inner Presence 268 We have the subjective feeling that we are at all times surrounded by world of coherent meaningful objects,    even when we do not necessarily focus on those objects or see them as tightly bound entities. 0
Revonsuo; Inner Presence 268 When we focus on an object,    it instantaneously becomes coherent and meaningful;    and after we have focused on it even once, it tends to remain meaningful for us even if it becomes just blurry figure in the phenomenal background. 0
Revonsuo; Inner Presence 269 Neural Mechanisms of Binding 1
Revonsuo; Inner Presence 269 Grandmother cell coding,    population coding,    and temporal coding    are the three major theories that had been put forward to solve the neural binding problem. 0
Revonsuo; Inner Presence 272 Temporal Binding 3
Revonsuo; Inner Presence 272 The notion of temporal coding    posits that one specific cell assembly    is distinguished from others    by the synchronicity of firing    in all the members belonging to the same assembly. 0
Revonsuo; Inner Presence 272 Different but simultaneously active assemblies can be distinguished from each other by the timing of their activity (rather than the level of activity). 0
Revonsuo; Inner Presence 272 Synchronous activity may constitute a recurrent regular pattern or oscillatory rhythm. 0
Revonsuo; Inner Presence 272 An oscillatory rhythm    exhibits a characteristic frequency of coherent neuron discharges    at perhaps 40 Hz. 0
Revonsuo; Inner Presence 272 Wolfgang Singer, one of the main architects of the theory of temporal coding, presented several predictions that may be derived from the temporal coding hypothesis. 0
Revonsuo; Inner Presence 272 Spatially segregated neurons    should synchronize their responses    if activated by features    that can be grouped together    to form one perceptual unit. 0
Revonsuo; Inner Presence 272 Synchronization    should be frequent among neurons within a particular cortical area,    but it should also occur across cortical areas. 0
Revonsuo; Inner Presence 272 The probability that neurons synchronize their responses    both within a particular area    and across areas    should reflect some of the gestalt criteria    used for perceptual grouping. 0
Revonsuo; Inner Presence 272 Individual cells    must be able to rapidly change the partners    with which they synchronize their responses    if stimulus configurations change and require new associations. 0
Revonsuo; Inner Presence 272 If more than one object is present in a scene,    several assemblies should form. 0
Revonsuo; Inner Presence 272 Synchronization probability    should depend on the functional architecture of reciprocal corticocortical connections    and should change if this architecture is modified.  Specifically, the disruption of synchronization should impair visual perception. 0
Revonsuo; Inner Presence 273 Synchronization of neural activity has been found to oscillate around 35 to 45 Hz. 1
Revonsuo; Inner Presence 273 Synchronization is observable    among adjacent cells in the same visual area,    between spatially segregated cell groups within the same visual area,    between groups in different visual areas,    and even between groups of cells located in visual areas of the two different hemispheres. 0
Revonsuo; Inner Presence 273 Gestalt features of the stimulus    strongly modulate    synchronization. 0
Revonsuo; Inner Presence 273 Wolfgang Singer suggests that synchronization reflects Gestalt criteria for perceptual grouping (proximity, similarity, continuity, common fate). 0
Revonsuo; Inner Presence 273 Singer has suggested that neural mechanisms of synchronization are primarily mediated by intracortical (i.e. corticocortical) connections. 0
Revonsuo; Inner Presence 273 A theoretical model of synchronizing connections incarnates the Gestalt criteria for perceptual grouping. 0
Revonsuo; Inner Presence 274 Synchronization spreads    to all those neurons in the interaction skeleton    that are both independently activated    and directly connected by Gestalt cues. 1
Revonsuo; Inner Presence 274 Local synchronization is easily achieved because of the perceptual grouping criterion of proximity. 0
Revonsuo; Inner Presence 274 The spread of synchronization    to neurons not directly connected with each other    could be achieved by a regular firing pattern,    such as oscillations within a narrow frequency band. 0
Revonsuo; Inner Presence 274 A regularly oscillating rhythm is essential for global synchronization between all the elements of that whole. 0
Revonsuo; Inner Presence 274 Global synchronization can be established via the transitivity of synchronization even across several synaptic connections. 0
Revonsuo; Inner Presence 274 If each pair of two adjacent, directly connected cells are firing in synchrony with the same regular frequency, then necessarily all the neurons participating in the same pattern do, even ones distant from each other in the interaction skeleton. 0
Revonsuo; Inner Presence 274 This transitivity of synchronization is proposed to account for the nonlocal Gestalt grouping criteria. 0
Revonsuo; Inner Presence 274 Transitivity of synchronization could create the connectedness between separated elements of the same contour of separate features of the same object. 0
Revonsuo; Inner Presence 274 Bottom-up binding during sensory input processing must be augmented by top-down influences that have a role in establishing perceptual wholes. 0
Revonsuo; Inner Presence 274 In Singer's theory, attention is seen as an internal, top down synchronization mechanism that is needed especially to organize complex feature combinations. 0
Revonsuo; Inner Presence 274 Attended percepts differ from non-attended ones in that the responses of neurons coding for the attended percept are strongly synchronized with each other. 0
Revonsuo; Inner Presence 274 Although the representation of the perceptual whole is realized in intracortical connections, the attentional modulation of synchronization may be realized through subcortical connections such as thalamocortical interactions. 0
Revonsuo; Inner Presence 277 Cortical synchronization can be observed even in anesthetized animals. 3
Revonsuo; Inner Presence 277 Researchers Engle and Singer have formulated specific ideas about the relationship between neural synchrony and consciousness.  They propose that there are four processes (arousal, segmentation, selection, working memory) that may together form the neural correlate of awareness, and that the neural mechanisms of each of these processes involves neural synchrony. 0
Revonsuo; Inner Presence 277 Arousal is characterized by an enhanced precision of neural synchrony and a shift to a high oscillation frequencies. 0
Revonsuo; Inner Presence 277 Arousal seems to be a necessary condition of awareness. 0
Revonsuo; Inner Presence 277 Phenomenal consciousness is always organized,    which requires the segmentation of different objects    from each other and the background. 0
Revonsuo; Inner Presence 277 If only a subset of all input information    is selected to awareness,    synchronization could act as a signature of those representations    that will be made globally available to the system. 0
Revonsuo; Inner Presence 278 Synchronization may transiently stabilize neural states so that the information can be held temporarily in a working memory mechanism. 1
Revonsuo; Inner Presence 278 Synchronization could be the mechanism of selective attention and reflective consciousness. 0
Revonsuo; Inner Presence 278 Researchers Engle and Singer speculate that temporal binding may establish patterns of large-scale coherence so that cross modality binding becomes possible. 0
Revonsuo; Inner Presence 278 Researchers Engle and Singer propose their overall view of the neural basis of consciousness    as a hierarchy of neural assemblies    bound together by neural interactions    in different frequency bands. 0
Revonsuo; Inner Presence 278 Researchers Engle and Singer propose that synchronization    is the neural mechanism    of all the major aspects of consciousness. 0
Revonsuo; Inner Presence 278 The original suggestion relating consciousness to neural synchrony goes back to Crick and Koch (1990) when they explicitly suggest a relationship between neural level binding through synchronization and the phenomenal level unity of perceived objects in visual consciousness. 0
Revonsuo; Inner Presence 278 Crick and Koch emphasize the role of attention    in generating coherent contents of consciousness,    but otherwise there theory is quite consistent with that of Singer. 0
Revonsuo; Inner Presence 278 Rodolfo Llinás (1994) proposed that 40 Hz oscillations    subserving temporal binding    are generated in thalamocortical loops. 0
Revonsuo; Inner Presence 279 Much of the empirical evidence supporting the synchronization hypothesis has been based on invasive microelectrode studies of animal subjects. 1
Revonsuo; Inner Presence 281 The temporal coding hypothesis has been found to be the most promising candidate to account for consciousness-related binding. 2
Revonsuo; Inner Presence 281 Empirical evidence from animal studies using multiunit recordings and from human studies using scalp recordings support the view that unified visual wholes are constructed with the help of synchronized neural oscillations in the gamma band. 0
Revonsuo; Inner Presence 312 Only those events that were consciously apprehended or perceived at the time of their occurrence can lead to subsequent conscious recollection. 31
Revonsuo; Inner Presence 312 Much of the phenomenal visual field    leaves no traces    behind in the hippocampus. 0
Revonsuo; Inner Presence 312 Hippocampus    is densely connected    to a multitude of different areas. 0
Revonsuo; Inner Presence 312 The parietal lobe    appears to be most important for bodily awareness    and awareness of space. 0
Revonsuo; Inner Presence 312 It seems that large-scale interaction between different areas is required for the phenomenal level of consciousness. 0
Revonsuo; Inner Presence 312 Mechanisms of consciousness consists of networks in the brain that connect the diverse contents of consciousness into one coherent whole. 0
Revonsuo; Inner Presence 312 The constituted mechanisms of consciousness must include an anatomically widespread complex network. 0
Revonsuo; Inner Presence 313 In hemispatial neglect, half of phenomenal space disappears..  Typically, the lesions causing neglect in different patients overlap in the inferoposterior parietal region. 1
Revonsuo; Inner Presence 313 Epileptic absence seizures,    general anesthesia,    and NREM sleep    are all states in which the phenomenal level is temporarily disabled.    All of them involve remarkable changes in thalamocortical function. 0
Revonsuo; Inner Presence 314 Epileptic absence seizures involve a brief transient loss of consciousness.    The cause of this loss appears to be the disruption of the high frequency thalamocortical oscillations.    Suddenly, large numbers of thalamocortical loops are recruited to a much stronger, low-frequency (~3 Hz) pattern of the oscillatory activity. 1
Revonsuo; Inner Presence 314 High frequency oscillations in the thalamocortical system appear necessary for supporting the phenomenal level. 0
Revonsuo; Inner Presence 314 Functional brain imaging experiments on the loss of consciousness during anesthesia also point to the importance of the thalamus. 0
Revonsuo; Inner Presence 314 A reduction in thalamocortical output may underlie the loss of consciousness in anesthesia. 0
Revonsuo; Inner Presence 314 Brain imaging studies have revealed that during NREM sleep,    glucose and oxygen utilization in the thalamus is radically lowered.    This finding supports the idea that the thalamic level is strongly deactivated in NREM sleep. 0
Revonsuo; Inner Presence 314 Data from various sources indicate that high frequency oscillatory activity in the thalamocortical network plays a decisive role in the mechanism of the conscious state. 0
Revonsuo; Inner Presence 314 Thalamus forms complex feedback circuits with the cortex. 0
Revonsuo; Inner Presence 314 Two types of thalamocortical networks can be distinguished -- diffused and focused. 0
Revonsuo; Inner Presence 315 All visual cortical areas have their own independent connections with the thalamus. 1
Revonsuo; Inner Presence 315 Overall picture that emerges from current theories is that the neural constituents of consciousness are not spatially localized in one precise place in the brain.  Instead, they probably form a complex system of corticocortical and thalamocortical networks, each contributing some essential features to the phenomenal level of organization. 0
Revonsuo; Inner Presence 315 Synchronous neural activity at high frequencies is the leading candidate among the potential neurophysiological mechanisms of consciousness. 0
Revonsuo; Inner Presence 315 Gamma band oscillatory activity is involved in the conscious perception of unified visual objects both in humans and animals. 0
Revonsuo; Inner Presence 315 Synchronization related to visual awareness of objects has been detected by invasive microelectrodes as well as noninvasive scalp electrodes. 0
Revonsuo; Inner Presence 315 Some researchers propose that gamma-band synchronous activity in the cortex is necessary for consciousness.  Others regard synchronicity in the thalamocortical loops and subcortical circuits as more Important for consciousness. 0
Revonsuo; Inner Presence 315 The anatomy and physiology of thalamocortical connections seemed just right for producing large-scale synchronous patterns. 0
Revonsuo; Inner Presence 315 Thalamic cells show inherent oscillatory rhythmicity, and their connections to the cortex support both specific loops and widespread loops of coherent activity. 0
Revonsuo; Inner Presence 315 There are both empirical and theoretical reasons to believe that synchronicity might serve as a mechanism for consciousness. 0
Revonsuo; Inner Presence 315 Empirical evidence from a variety of sources points to a connection between consciousness and gamma-band synchronicity. 0
Revonsuo; Inner Presence 316 Singer (2000) proposed that metarepresentations are the higher-level neural entities on which consciousness is based. 1
Revonsuo; Inner Presence 316 Metarepresentations have a rich combinatorial complexity, the ability to reconfigure themselves rapidly, and the ability to handle contents that are completely unpredictable. 0
Revonsuo; Inner Presence 316 Temporary association of neurons into functionally coherent assemblies could be the way to build metarepresentations. The assemblies could be defined by synchronization. 0
Revonsuo; Inner Presence 316 Conceptually, build higher-level electrophysiological entities resembling the phenomenal objects in consciousness by using synchronicity of large neural assemblies as the mechanism. 0
Revonsuo; Inner Presence 316 Synchronicity could be the microlevel mechanism underlying the phenomenal contents of consciousness. 0
Revonsuo; Inner Presence 316 Dynamic core hypothesis (Edelman and Tononi, 2000) might be the basis of consciousness.  The dynamic core is a cluster of neuronal groups that strongly interact among themselves.  The cluster as a whole has distinct functional or physiological (rather than anatomical) borders with the rest of the brain. 0
Revonsuo; Inner Presence 316 Where in the brain is the dynamic core localized?  Reentrant connections in the thalamocortical system are involved, but otherwise it is not localizable. 0
Revonsuo; Inner Presence 316 The term "dynamic core" deliberately does not refer to a unique, invariant set of brain areas, and the core may change in composition from moment to moment. 0
Revonsuo; Inner Presence 318 Master Loop Hypothesis 2
Revonsuo; Inner Presence 319 According to the master loop hypothesis the neural substrate of consciousness consists of large-scale electrophysiological or bioelectrical activity patterns that are enormously complex (probably involving millions of neurons and billions of synapses). 1
Revonsuo; Inner Presence 319 Synchronous oscillations or other forms of spatiotemporal coherent neural activity in the large-scale networks are the mechanism by which the conscious state, the subphenomenal space, and it's phenomenal contents are realized in the brain. 0
Revonsuo; Inner Presence 319 The master loop networks are characterized by an architecture of recurrent connectivity.  That special architecture supports closed loops of coherent bioelectrical activity.  The loops extend "horizontally" across the cortex (like the feedback sweep in the ventral visual stream) and also "vertically" between the cortex and the thalamus ("specific" and "nonspecific" thalamocortical loops). 0
Revonsuo; Inner Presence 320 Top-down constraints take the features of subjective experience as a starting point, and try to descend from them to the features of the constitutive mechanisms. 1
Revonsuo; Inner Presence 320 Bottom-up constraints look at neural systems that could realize large-scale coherent states and thus be plausible candidates for mechanisms of consciousness. 0
Revonsuo; Inner Presence 320 Evidence for the neural basis of consciousness comes from many different empirical and theoretical sources.  When the sources are integrated, a converging picture starts to emerge.  Regarding the neural correlates of visual consciousness, the primary visual area and the frontal cortex seem to be not necessary. 0
Revonsuo; Inner Presence 320 Parietal areas are necessary for the body image and the self. 0
Revonsuo; Inner Presence 320 A network of thalamocorticosubcortical connections seems necessary for phenomenal space and for the state of being conscious. 0
Revonsuo; Inner Presence 320 Coherent neural activity at high frequencies in the thalamocorticosubcortical areas is the prime candidate for the physiological mechanism that might constitute consciousness. 0
Revonsuo; Inner Presence 320 The phenomenal level is not localized in any single cortical lobe, but involves a large distributed network of recurrent neural activities in corticocortical and thalamocortical loops. 0
Revonsuo; Inner Presence 328 EEG abd MEG signal sources. (diagram) 8
Revonsuo; Inner Presence 330 Functional brain imaging with PET and fMRI. 2
Revonsuo; Inner Presence 331 Neither PET  nor fMRI detects electrophysiological or bioelectrical signals. 1
Revonsuo; Inner Presence 331 PET detects gamma rays that originate when a positron is annihilated in the brain. The positron is generated when a radioactive isotope in the tracer compound (e.g. a radioactively labeled water or glucose molecule) in the bloodstream decays. 0
Revonsuo; Inner Presence 331 In fMRI, it is the relative amount of oxygenated vs. deoxygenated blood that is being detected, for these two forms display slightly different magnetic properties. 0
Revonsuo; Inner Presence 331 The vascular supply where fMRI response is realized is regulated at a spatial scale (0.5 -- 1.5 mm in humans) that is several orders of magnitude larger than individual neurons.  This fact limits the ultimate spatial revolution achievable with fMRI. 0
Revonsuo; Inner Presence 333 PET and fMRI images are not images of neurons or neural electrical activity, but of changes in the circulatory system in the brain. 2
Revonsuo; Inner Presence 333 In the temporal dimension, when neural activity increases in a location, there is a delay of several seconds before blood flow increases.  The fMRI signal starts at two seconds and reaches its peak at about 13 seconds from the stimulus onset. 0
Revonsuo; Inner Presence 333 The colorful computer-generated images produced by PET and fMRI are not "images of the mind" or even "neuroimages," but rather images of blood flow or blood oxygenation levels in the brain. 0
Revonsuo; Inner Presence 333 Structural MRI images mostly reflect proton densities of different tissues and give good spatial resolution and contrast between different tissues. 0
Revonsuo; Inner Presence 335 Consciousness, or the phenomenal level of organization, probably resides at higher levels of complex electrophysiological and bioelectrical phenomena in the brain. 2
Revonsuo; Inner Presence 345 Global patterns of organized bioelectrical activity that constitutes the phenomenal level change in about the rate of once in 100 to 300 ms. 10
Revonsuo; Inner Presence 345 Synchronous oscillations on which the phenomenal level is based at the underlying microlevels are probably within the gamma range (20 -- 80 Hz). 0
Revonsuo; Inner Presence 345 The temporal resolution of the data recording must be at least as high as the rate of reorganization of the phenomenal level. 0
Revonsuo; Inner Presence 345 What is the spatial scale in which the subjective just-noticeable differences of spatial location are realized within the phenomenal level?  We may speculate that it must be courser than the spatial scale of single neurons, but certainly much finer than the scale of 1 mm3. 0
Revonsuo; Inner Presence 345 An ideal neural signal data recorder would sample data at the rate of 100 Hz, and could resolve spatial details of activity in volumes of space around 10-4mm3. 0
Revonsuo; Inner Presence 345 An ideal neural signal data recorder would collect signals at the levels where organized electrophysiological patterns are realized in recurrent loops of coherent activity. 0
Revonsuo; Inner Presence 346 An ideal neural signal data recorder would collect signals from a wide range of different frequencies across the whole brain, especially in corticocortical and thalamocortical loops. 1
Revonsuo; Inner Presence 352 A living organism as a unified whole cannot be described in the language of chemical formulas. 6
Revonsuo; Inner Presence 355 Objective neural mechanisms and subjective consciousness can be seen as a line along the same gapless continuum. 3
Revonsuo; Inner Presence 355 Neuroscience will have to be a rationalized with a phenomenal level as an integral part of the biological brain, and the empirical data must be phenomenalized and subjective consciousness itself used as the domain of theoretical modeling. 0
Revonsuo; Inner Presence 355 Consciousness and neuroscience must meet across the explanatory gap, each coming halfway to meet the other. 0
Revonsuo; Inner Presence 364 Consciousness surely seems to make an enormous difference in our behavior. 9
Revonsuo; Inner Presence 368 Blindsight -- patient does not see anything in the blind part of the visual field, but somehow the behavioral responses are influenced by the unseen stimuli. Blind regions in the visual fields result from brain injury to the primary visual cortex (V1). 4
Revonsuo; Inner Presence 369 Prosopagnosia -- inability to recognize familiar people from their faces. 1
Revonsuo; Inner Presence 370 Unilateral neglect -- dramatic loss of awareness of one side of space, remains a mystery, because the primary sensory pathways may still be intact, and yet the patient is not aware of the stimulus. 1
Revonsuo; Inner Presence 401 Biological Function of Dreaming 31
Revonsuo; Inner Presence 427 Converging evidence from a wide variety of sources supports the view that the nocturnal world simulation we know as "dreaming" is functionally specialized in the simulation of dangers and threatening events. 26
Revonsuo; Inner Presence