Jeffrey Alan Gray - Disagreement With Functionalism

Disagreement With Functionalism

Gray disagreed with the functionalist theory of consciousness. He described the position of functionalism as saying that consciousness is the nature of certain complex systems, regardless of whether they are made of neurons, silicon chips or some other material. The underlying tissues or machinery are irrelevant. Further to that consciousness relates only to functions performed by the brain or other system, and does not arise as a result of anything that is not functional. For any discriminated difference in qualia, there must be a difference in function. It is also claimed that for every discriminated difference in function, there is a difference in qualia.

In discussing this question further, Gray looked at synaesthesia, where he described modalities as becoming mixed, as when numbers or sounds are experienced with colour. Experimentation in recent years has demonstrated that synaesthesia is most likely the consequence of abnormal projections into the V4 colour region of the visual cortex from other parts of the brain. Brain scanning studies have shown that when words are spoken, in addition to the normal activity in the auditory cortex, the V4 colour vision area in the visual cortex became active, in a way which does not occur in normal subjects. There was no related activation in V1 or V2, the earlier stages of the visual pathway. The conclusion drawn from a whole series of experiments was that the 'word-type' of synaesthete has an abnormal projection from the auditory cortex into the visual cortex causing the V4 colour area to produce consciousness of colour. However, there is no evidence that this colour sensation has any function.

Gray argued from these findings that there was no relationship between the occurrence of the synaesthete's colour experience and the linguistic function that triggers them. Gray argues that this phenomenon refutes the functionalist analysis of consciousness, because the theory claims that conscious experience relates only to functions performed in the brain, and does not arise as a result of anything that is not functional, as is claimed to be the case with this type of synaesthesia.

Gray also discussed the Penrose/Hameroff Orch-OR theory of consciousness. His main objection to this is the question as to why particular wave function collapses should select for one particular qualia. He also questions the temporal aspect of Hameroff's model, where the proposed 25 milliseconds to wave function collapse is only a tenth of the time considered necessary for a conscious perception to form.