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Consciousness as crosstalk
Consciousness as crosstalk
Conscious
states are a crosstalk mechanism for only a subset of brain processes
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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