This debate highlighted some of the problems that bedevil modern consciousness studies. One such problem is the tendency to elide the self with consciousness. A more detailed analysis suggests that the self is not the same thing as consciousness, but instead merely a part of the contents of consciousness. The main components of the self are, firstly the necessary distinction between the body and the environment, and secondly the narrative history in our memory. Sensory input can temporarily extract us from engagement with the self, and loss of self is a feature of altered but still conscious states.
The problem of consciousness is thus not about the self but about the qualia, ‘the something it is like’ of sensory experience. In this debate, one speaker emphasised the importance of sensory input, but seemed to try to get round it in a way that is alien to the scientific method, by saying that the existence of qualia prior to the question about why they existed somehow answered the question. On this basis, the fact that electricity existed before anyone asked what it was could be taken to answer the question of what it was, whereas in science this had to wait for the understanding of charges particles and electromagnetic waves. The same type of understanding is needed with consciousness. Similarly, it is no good arbitrarily declaring that consciousness is an illusion, because as another speaker pointed out, this simply raises the unanswered question of who or what is having the illusion.
The discussion of the emotions gave rise to further problems. It is not correct to locate emotions solely in the brain stem as seemed to be suggested here. Research in recent years has indicated the most important areas relative to emotion to be the orbitofrontal, the anterior cingulate, the amygdala and parts of the basal ganglia. The orbitofrontal looks to be crucial for evaluating the reward/punisher qualities of sensory inputs, while the anterior cingulate evaluates the cost effectiveness of particular actions, and also monitors their subsequent consequences relative to expectations.
Subjective judgement is seen to be physical in these areas because the levels of neural activity correlate to the subjective assessment of the inputs, rather than the strength of the incoming signal, which determines earlier activity in the sensory cortex. The orbitofrontal and anterior cingulate are interative with dorsolateral prefontal area, which is related to the working memory, reasoning and planning. It is notable that damage to the orbitofrontal makes even the simplest decision taking difficult.
It is important to understand the system described above, by which deliberative action is related to subjective evaluation, is largely separate from the system observed by Libet and mentioned in the debate here. Spontaneous movements are driven by the unconscious dorsal visual stream, while sensory experience and its subsequent evaluation come via the mainly separate and conscious ventral visual stream. The recent neuroscience on which this is based effectively invalidates the oft repeared claim that Libet disproved the existence of conscious will.
When we talk of will, the most important aspect appears to be the subjective reward/punisher judgement of sensory inputs, which in turn colour rational and planned decision taking and behaviour. One can call this conscious or subjective will. I think it muddies the waters to discuss whether it is free or not. Other processes in the physical universe are constrained to some extent, and this seems likely to apply to the physical process of consciousness.
Tags: anterior cingulate, consciousness, emotions, freewill, orbitofrontal, qualia, self Posted by