Understanding Psychology (10th Ed)

parts of the nervous system. Biological factors are central to our 
sensory experiences, states of consciousness, motivation and 
emotion, development throughout the life span, and physical 
and psychological health. Furthermore, advances in behavioral 
neuroscience have led to the creation of drugs and other treat-
ments for psychological and physical disorders. In short, we 
cannot understand behavior without understanding our biological 
makeup (Compagni & Manderscheid, 2006; Kosslyn et al., 2002; 
Plomin, 2003).
behavioral neuroscientists (or biopsychologists)
Psychologists who 
specialize in considering the ways in which the biological structures 
and functions of the body aff ect behavior.
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Watching Serena Williams hit a stinging backhand, Dario Vaccaro dance a complex 
ballet routine, or Derek Jeter swing at a baseball, you may have marveled at the 
complexity—and wondrous abilities—of the human body. But even the most every-
day tasks, such as pouring a cup of coffee or humming a tune, depend on a sophis-
ticated sequence of events in the body that is itself truly impressive. 
The nervous system is the pathway for the instructions that permit our bodies 
to carry out such precise activities. Here we look at the structure and function of 
neurons, the cells that make up the nervous system, including the brain.
The Structure of the Neuron
Playing the piano, driving a car, or hitting a tennis ball depends, at one level, on 
exact muscle coordination. But if we consider how the muscles can be activated so 
precisely, we see that more fundamental processes are involved. For the muscles to 
produce the complex movements that make up any meaningful physical activity, the 
brain has to provide the right messages to them and coordinate those messages. 
Such messages—as well as those which enable us to think, remember, and 
experience emotion—are passed through specialized cells called neurons.