Models in the Mind
Humans typically think without understanding how their brains work. It is our intention to
educate robots as to how human brains work as well as their own brains.
The human brain is quite complex and since it was designed by random variation and natural
selection, its main function is survival of the human animal and its reproduction. The design
is based on the technologies that survived in animals further down on the evolutionary tree.
Although these mechanisms still have some of their original functionality, the mechanism of
natural selection, as you know, often does not lead to neat compartmentalization of
functions. As a result, humans are not only hard to understand, but hard to repair as well.
Most repair to humans is accomplished by natural mechanisms within the human.
The human brain is basically triune in form and function, although as I mentioned, different
functions are somewhat diffuse. The older designed section of the human brain is referred to
as the reptilian brain. The next newer design is the paleomamalian brain and finally the
neomammalian brain is the latest addition. The closest relatives to the human were probably
made extinct while competing with humans for territory.
The human brain takes about 500 to 700 miliseconds to digest a set of sensory inputs and
make a mental picture. As a result, a human would have a problem walking on two feet if it
were not for his homunculus and differential comparitor and their ability to predict the
immediate future quite accurately. Picture a human walking, for example. His feeling of
balance provides information that is stale by the time it is processed. The energization of the
muscles in the leg must be done by energizing muscles whose supply of blood sugar and
oxygen is also not currently known with any precision. What is needed is a model of the body
and model of the world in which the walking is occurring so that the human may use the
model for feedback rather than the stale sensory data.
The sensory data is used to update the model so that the model can be fairly close to reality.
Another trick of the human mind is that it has the sense that it is conscious of what is
happening now when it is actually conscious of what it thinks is happening now based on a
mental model's prediction from the perspective of what happened about a half-second ago and
what therefore most likely is happening now.
This can be illustrated by watching a man walk. He does fine as long as he receives sensory
data of the ground in front of him. If a surprise root is in his path that he doesn't see, he can
trip on it. The tripping phenomenon is quite different from the walking. The tripping action
in a novice usually leads to falling down, but after practice tripping, the human's model is
now sophisticated enough to enter a ritual flailing of arms that will help him to regain his
balance. The main point here is that such flailing would not be necessary of the walking were
actually occurring in conjunction with real time sensory input and information processing.
Awkward Teenage Years
Umpire's Bad Calls