Praise for Trading from Your Gut

amygdala, the hypothalamus, and the hippocampus. The limbic
system is responsible for emotion and feelings. 
Considerable evidence also suggests that the limbic system is at
the center of the brain’s evaluation systems. Emotion and feelings
are, after all, evaluations of value. Animals, including humans, have
pleasurable or pleasant feelings toward those things that benefit
them. Animals have negative sensations or feelings toward those
things that might harm them. Sweet, healthy food tastes good. Food
that contains natural poisons generally tastes bad. The sense of taste
provides a natural mechanism for evaluating between food choices.
The limbic system’s evaluation mechanisms manifest in other
ways. For example, damage to the hippocampus results in the
inability to store memories. Scientists theorize that this occurs
because of the inability to sort out which inputs are worthy of
remembering. If the brain can’t rate memories, it can’t store new
ones.
The third section is the neocortex (Latin for “new bark”), or
neomammalian brain (Latin for “new mammal brain”). This sec-
tion is present only in mammals. The neocortex is a thin layer—
composed of six individual layers of neuron cells—that surrounds
the rest of the brain. In many smaller mammals, the neocortex is
smooth. However, in larger mammals, primates, and humans, the
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From the Library of Daniel Johnson

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neocortex takes on a wrinkled shape that enables it to have a much
larger surface area for a given brain size. The neocortex appears to
have the same basic composition in all sections of the brain.
Compared with other animals, human beings have an oversized
brain. The human brain is much larger as a percentage of body mass
than the brain of any other animal. Most of this extra mass is con-
tained in the neocortex. The neocortex is the part of the brain that is
responsible for higher-order thinking. It contains most of what
makes us smarter than other animals.
Because the neocortex is the source of human intelligence, it is
important to note that both the left and right hemispheres are parts
of the same neocortex. Both hemispheres are intelligent and logical
at their core.