1. 22 WHAT EVERY B O D Y I S S AY I N G
“brains” inside the human skull, each performing specialized functions
that work together as the “command-and-control center” that regulates
everything our body does. Back in 1952, a pioneering scientist named
Paul MacLean began to speak of the human brain as a triune brain con-sisting
of a “reptilian (stem) brain,” “mammalian (limbic) brain,” and “hu-man
(neocortex) brain” (see diagram of the limbic brain). In this book, we
will be concentrating on the limbic system of the brain (the part MacLean
called the mammalian brain), because it plays the largest role in the ex-pression
of our nonverbal behavior. However, we will use our neocortex
(our human brain or thinking brain) to analyze critically the limbic reac-tions
of those around us in order to decode what other people are think-ing,
feeling, or intending (LeDoux, 1996, 184–189; Goleman, 1995,
10–21).
It is critical to understand that the brain controls all behaviors, whether
conscious or subconscious. This premise is the cornerstone of understand-ing
all nonverbal communications. From simply scratching your head to
composing a symphony, there is nothing you do (except for some involun-tary
muscle reflexes) that is not governed or directed by the brain. By this
Fig. 3
Neocortex
Hypothalamus
Amygdala
Reptilian Brain
Corpus Callosum
Thalamus
Hippocampus
Cerebellum
Diagram of the limbic brain with major features such as the amygdala and the
hippocampus.