Neurophysiology of Consciousness

ISBN-13: 9780817635381 / Angielski / Twarda / 1993 / 404 str.

B. Libet; Benjamin Libet;Libet

Opis

and made insignificant in practice, by selecting for study simple kinds of ex- periences which are devoid of emotional content and which can be tested for reliability. A simple somatosensory ''raw feel" fulfills these characteristics (see papers nos. 2,5). In any case, if we fail to find ways to use introspective reports in convincingly acceptable studies we would give up the ability to investigate the relation between conscious experience and neural activity, something warned against by William James (Krech, 1969). Another factor in the dearth of direct experimental studies is, of course, the comparative inaccessibility of the human brain for such purposes. Meaningful investigations of the issue in question requires simultaneous study of brain events and introspective reports of experiences in an awake, cooperative human subject. Analysis by neuropsychologists of pathological lesions in the brain and the related disturbances of conscious functions have contributed much to mapping the pos- sible representations of these functions. The non-invasive recording of electrical activity with electrodes on the scalp, starting from Berger's initial EEG record- ings in 1929, has contributed much to the problems of states of consciousness and to various cognitive features associated with sensory inputs, but not as much to the specific issue of conscious experience.

Spis treści

1 Production of Threshold Levels of Conscious Sensation by Ectrical Stimulation of Human Somatosensory Cortex (1964).- 2Cortical Activation in Conscious and Unconscious Experience (1965).- 3Brain Stimulation and the Threshold of Conscious Experience (1966).- 4Responses of Human Somatosensory Cortex to Stimuli below Threshold for Conscious Sensation (1967).- 5Electrical Stimulation of Cortex in Human Subjects, and Cscious Sensory Aspects (1973).- 6Cortical Representation of Evoked Potentials Relative to Conscious Ssory Responses, and of Somatosensory Qualitites — in Man (1975).- 7Cortical and Thalamic Activation in Conscious Sensory Eerience (1972).- 8Neuronal vs. Subjective Timing for a Conscious Sensory Eerience (1978).- 9Subjective Referral of the Timing for a Conscious Sensory Experience: Aunctional Role for the Somatosensory Specific Projection Stem in Man (1979).- 10 Retroactive Enhancement of a Skin Sensation by a Delayed Cortical Smulus in Man: Evidence for Delay of a Conscious Ssory Experience (1992a) 196.- 11 The Experimental Evidence for Subjective Referral of a Ssory Experience Backwards in Time: Reply to P.S. Churchland (1981).- 12 Brain Stimulation in the Study of Neuronal Functions for Cscious Sensory Experiences (1982a).- 13 Readiness -Potentials Preceding Unrestricted “Spontaneous” vs. P-Planned Voluntary Acts (1982b).- 14 Preparation- or Intention-to-Act, in Relation to Pre-Event Potentials Rorded at the Vertex (1983a).- 15 Time of Conscious Intention to Act in Relation to Onset oCerebral Activity (Readiness-Potential): The Unconscious Itiation of a Freely Voluntary Act (1983b).- 16 Unconscious Cerebral Initiative and the Role of Cscious Will in Voluntary Action (1985).- 17 Are the Mental Experiences of Will and Self-Control Significant for the Pformance of a Voluntary Act? Response to Commentaries bL. Deecke and by R.E. Hoffman and R.E. Kravitz (1987a).- 18 Consciousness: Conscious, Subjective Experience (1987b).- 19 The Timing of a Subjective Experience. Response to a Cmentary by D. Salter (1989a).- 20 Conscious Subjective Experience vs. Unconscious Mental Functions: Aheory of the Cerebral Processes Involved (1989b).- 21 Control of the Transition from Sensory Detection to Sensory Awareness in May by the Duration of a Thalamic Stimulus: The Cerebral “Time-On” Factor (1991).- 22 The Neural Time-Factor in Perception, Volition and Free Will (1992b).- Elogue I: Some Implications of “Time-On„Theory.- Elogue II: A Testable Field Theory of Mind-Brain Interaction.- Permissions.