Online research in philosophy

This paper considers the so-called explanatory gap between brain activity and conscious experience. A number of different, though closely related, explanatory gaps are distinguished and a monistic account of conscious experience, a version of Herbert Feigl's "dual-access theory," is advocated as a solution to the problems they are taken to pose for physicalist accounts of mind. Although dual-access theory is a version of the mind-body identity thesis, it in no way "eliminates" conscious experience; rather, it provides a parsimonious and explanatorily fruitful theory of the consciousness-body relation which faithfully preserves the nature of conscious experience while going quite far in "bridging" the various explanatory gaps distinguished below.

An extended examination of Libet's works led to a comprehensive reinterpretation of his results. According to this reinterpretation, the Minimum Train Duration of electrical brain stimulation should be considered as the time needed to create a brain stimulus efficient for producing conscious sensation and not as a basis for inferring the latency for conscious sensation of peripheral origin. Latency for conscious sensation with brain stimulation may occurafterthe Minimum Train Duration. Backward masking with cortical stimuli suggests a 125-300 ms minimum value for the latency for conscious sensation of threshold skin stimuli. Backward enhancement is not suitable for inferring this latency. For determining temporal relations between stimuli that correspond to subjects' reports, theendof cerebral Minimum Train Duration should be used as reference, rather than its onset. Results of coupling peripheral and cortical stimuli are explained by a latency after the cortical Minimum Train Duration, having roughly the same duration as the latency for supraliminal skin stimuli. Results of coupling peripheral stimuli and stimuli to medial lemniscus (LM) are explained by a shorter LM latency and/or a longer peripheral latency. This interpretation suggests a 230 ms minimum value for the latency for conscious sensation of somatosensory near-threshold stimuli. The backward referral hypothesis, as formulated by Libet, should not be retained. Long readiness potentials preceding spontaneous conscious or nonconscious movements suggest that both kinds of movement are nonconsciously initiated. The validity of Libet's measures of W and M moments (Libet et al., 1983a) is questionable due to problems involving latencies, training, and introspective distinction of W and M. Veto of intended actions may be initially nonconscious but dependent on conscious awareness.

An old philosophical problem, the mind-body problem, has not been yet solved by philosophers or scientists. Even if in cognitive neuroscience has been a stunning development in the last 20 years, the mind-body problem remained unsolved. Even if the majority of researchers in this domain accept the identity theory from an ontological viewpoint, many of them reject this position from an epistemological viewpoint. In this context, I consider that it is quite possible the framework of this problem to be wrong and this is the main reason the problem

could not be solved. I offer an alternative, the epistemologically different world’s perspective, which replaces

the world or the universe. In this new context, the mind-body problem becomes a pseudo-problem.

The mind-body problem concerns the relationship between mind and body, or nowadays - between mind or consciousness and the brain. As a relationship, this can be viewed from two perspectives: from body to mind and from mind to body. In this note I point out that the two readings of the problem are not symmetrical and that there are categorical differences between them. In particular, whereas the body to mind problem constitutes a mystery (cf. the contemporary hard problem), the mind to body problem may be approached from a psychological (as contrasted with philosophical) orientation that allows for concrete phenomenological investigation.

Benjamin Libet and also Libet and collaborators claim to advance a single hypothesis, with important consequences, about the time of a conscious experience in relation to the time when there occurs a certain physical condition in the brain. This condition is spoken of as

_neural_

_adequacy_ for the experience, or, as we can as well say, _neural adequacy_ .⁵ This finding has been taken to throw doubt on theories that take neural and mental events to be in necessary or lawlike connection, and also certain identity theories of mind and brain, as well as determinist theories.

Evidence that led to the hypothesis of a backwards referral of conscious sensory experiences in time, and the experimental tests of its predictions, is summarized. Criticisms of the data and the conclusion by Churchland that this hypothesis is untenable are analysed and found to be based upon misconceptions and faulty evaluations of facts and theory. Subjective referral in time violates no neurophysiological principles or data and is compatible with the theory of "mental" and "physical" correspondence.