Consciousness is characterized by the following properties:
- selectivity: only a few neural processes are conscious
- exclusivity: only one perception at the time can be conscious
- chaining: one conscious thought leads to another, as in Hebb's "phase sequence"
- unitarity: the sense of self
These features can be explained by a process that relies on "positive" feedback.
Feedback can be negative (the familiar one, which has to do with
stabilizing a process, in particular its input with its output) or positive.
Positive feedback works in the opposite direction, at the edge of instability:
the signal is amplified by itself, weakening the relationship between input
and output.
A loop of positive feedback spreads through different areas of the brain and
provides "selective amplification".
Consciousness depends on negative feedback.
According to this theory,
the unification of consciousness occurs at the bottom of the sensory pyramid,
not at the top.
TM, ®, Copyright © 2005 Piero Scaruffi
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