Voluntary acts are preceded by electrophysiological (RPs). With spontaneous acts involving no preplanning, the main negative RP shift begins at about200 ms. Control experiments, in which a skin stimulus was timed (S), helped evaluate each subject's error in reporting the clock times for awareness of any perceived event.

Conscious experience is one of the most difficult and thorny problems in psychological science. Its study has been neglected for many years, either because it was thought to be too difficult, or because the relevant evidence was thought to be poor. Bernard Baars suggests a way to specify empirical constraints on a theory of consciousness by contrasting well-established conscious phenomena - such as stimulus representations known to be attended, perceptual, and informative - with closely comparable unconscious ones - such as (...) stimulus representations known to be preperceptual, unattended, or habituated. Adducing data to show that consciousness is associated with a kind of global workplace in the nervous system, and that several brain structures are known to behave in accordance with his theory, Baars helps to clarify many difficult problems. (shrink)

within-field task as testing proceeded. (In any case, the two-field task is presumably a more difficult one than the one-field task. ...

The significance of consciousness in modern science is discussed by leading authorities from a variety of disciplines. Presenting a wide-ranging survey of current thinking on this important topic, the contributors address such issues as the status of different aspects of consciousness; the criteria for using the concept of consciousness and identifying instances of it; the basis of consciousness in functional brain organization; the relationship between different levels of theoretical discourse; and the functions of consciousness.