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7. The Animal Self : Neurobehavioral Correlates............

Chapter 7 Neurobehavioral Correlates

If there is a more wonderfully complex structure in the universe, I do not

know of it.

— Seymour S. Kety^1

Overview: Animals differ from plants in that they are capable of moving around
in search of food and mates and to avoid hostile environments. In order to take
goal-directed actions, the many cells in the animal body must coordinate in an
efficient way. The nervous system, with its complex communication network,
makes this possible. The building block of the nervous system is the neuron. Two
or more neurons are interconnected through a specialized contact called the
synapse, where a very narrow gap separates the two ends. The gap, called a syn-
aptic junction, relies on chemicals for the message to get across, providing a site
for intricate regulation and modulation. The prevailing theory is that synaptic
plasticity is the basis of learning and memory.
The nervous system evolved from a diffuse nerve net to a centralized struc-
ture called the brain. Primitive brains are concerned with the essential functions
of life: survival and procreation. To this, evolution added the emotional com-
ponent, providing the driving force for action. Topping all these is the cerebral
cortex, which regulates the primitive urge. For example, the inhibition of an
emotional impulse makes possible deferred gratification, an act that may even-
tually bring in a greater reward than what can be obtained from immediate
satisfaction. The cerebral cortex permits higher functions such as reasoning and
abstraction, and leads to emergence of the mind. The overall function of the
brain imparts unity to the behavioral self. Disruption of the brain leads to the
fragmentation of mind, and self.