Existing theories about the nature of conscious sensations are discussed. The oldest classification system contrasts dualist theories (which say consciousness is an abstract entity) with monist theories (which say consciousness is a concrete entity). A more recent system contrasts process theories ("consciousness is a process, not a thing") with vehicle theories (consciousness is a property of...
Attempts to augment the function of the human brain inevitably involve in some way what Block (1995) calls phenomenal consciousness—bodily sensations and perceptual experiences—the redness of a strawberry, the smell of newly-baked bread. At present there is no consensus among scientists about what such sensory experiences are. This Opinion piece points out some problems with one of the major...
A comparison is made between the frequency of local minima in the analytic power (AP) of intracranial EEG (ECoG) from waking and unconscious human subjects and the frequency of putative frames of consciousness reported in earlier psychological literature. In ECoG from unconscious subjects, the frequency of deep minima in AP is found to be a linear function of bandwidth. In contrast, in ECoG...
Power density spectra and phase synchrony measurements were taken from intracranial electrode grids implanted in epileptic subjects. Comparisons were made between data from the waking state and from the period of unconsciousness immediately following a generalised tonic-clonic seizure. Power spectra in the waking state resembled coloured noise. Power spectra in the unconscious state resembled...
(1) To examine the validity of comparing the phase of broad-band signals. (2) To measure phase synchrony over the whole head, at a variety of frequencies. The concept of broad band phase is investigated (a) by visual comparison of the time series of two channels of filtered data with the time series of the spatial analytic phase difference (SAPD) between the two channels and (b) using...