Ezequiel Morsella & Tiffany Jantz
In:- Consciousness and the Universe
The authors accept the consensus view that conscious states represent only a subset of brain processing, and that the integration of sensory information and most cognitive processes are unconscious, . It is suggested that identification of processes that are unconscious can reveal those processes that involve consciousness by a process of elimination. The hypothesis here is that consciousness establishes intra-brain communication for a subset of brain processes. These brain processes are suggested to the control of voluntary actions. This is designated as supramodular interaction theory (SIT).
The authors specify what is not involved in SIT. It does not relate to complexity, feedback, memory or meaning. Instead their attention is focused on conscious conflicts such as holding breath, pain suppression, suppression of socially inappropriate behaviour, or a physically difficult process such as trying to look right when there is a bright flash to the left. It is suggested that consciousness is involved when two brain processes work towards different actions. Where there is just a single stream of processing leading to an action, such as withdrawing a hand from a hot stove, there is no requirement for consciousness. In situations of conflict, it is suggested that the impulses from different and conflicting streams of brain processing are held in the ‘conscious field’. The authors describe the muscular system used for actions as a steering wheel that different parts of the brain try to control. Consciousness is viewed as the process by which conflicting parts of the brain communicate with one another. The authors accept that some process other than consciousness could in principle resolve these conflicts, but say that evolution has selected for consciousness to perform this function.
The authors think that within the brain consciousness derives from a particular type of processing involving interaction between regions rather than depending on a particular region. Different outcomes result according to whether there is interregional activity or not. Unconscious processing involves smaller brain networks than conscious processing. Consciousness is related to the ventral stream which is not used for execution of action, but is involved in knowledge-based selection of actions.
The authors are cautious in respect of the hypothesis that consciousness derives from the feedback loop between cortical and thalamic neurons, because we consciously experience smell, although in contrast to the other senses olfactory neurons go directly to the cortex, mainly the orbitofrontal and pyriform cortices rather than via the thalamus. However, the thalamus does subsequently receive inputs from the regions involved in olfactory processing.
Recent studies are claimed to show that consciousness is only involved in perceptions preceding actions or the experience of the result of actions. This chapter also touches on suggestion going back to Penfield in the mid twentieth century that consciousness derives from the subcortical rather than the cortical regions of the brain. The authors criticise the rush to label consciousness as an epiphenomena without understanding much about it.
This chapter seems to try to steer the consciousness debate towards the area of choice/preference or as described here the resolution of conflict, which accords with other studies correlating activity in evaluation/choice areas of the brain with subjective preferences or assessments. The suggestion that consciousness only arises in the communication of larger brain networks also accords with recent studies of the gamma synchrony. However, as the authors themselves remark there is no attempt to describe how subjectivity arises in a physical system, only how it functions.
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