The news from UCL that the brain’s so-called ‘supplementary motor
regions’, located in the medial frontal cortex, inhibit unconsciously-triggered
actions supports the classical idea that many or most of the brain's eventual
decisions are the result of a delicate balance between excitation and inhibition.
This has interesting implications for the design of non-human cognitive systems.
Most control systems for machines - including robots - are weighted far more
heavily towards excitation than towards inhibition. That's to say, the control
system takes account of incoming and resident data, reaches a conclusion and
implements it.
The brain, on the other hand, seems to operate by generating large numbers
of initiatives, most of which are inhibited, leaving only a tiny proportion
which turn into actioned results, after a complex (and almost entirely unconscious)
counter-balancing process.
Asimov's famous Laws Of Robotics, interestingly, lean towards the inhibitory
side. Although the study of neural nets, whose operating principles are often
set to be close to those of the brain, is at a very early stage, it may be that
this is the direction in which robotic control systems will develop, especially
if we want the robots to be 'humanoid' in their behaviour.
The UCL researchers' description of yet more unconscious elements in human
decision-making also throws further doubt on the role of consciousness and the
nature of free will. If the brain's decision process consists of a vastly complex
set of interacting factors and influences of which we are (consciously) quite
unaware, then how much freedom of action can we ascribe to the conscious 'I'?
