C
ases of brain injury and disease, like those
of Junior Seau and other athletes, vividly
remind us that the 3-pound organ inside our
skulls provides the bedrock for everything
we do, feel, and think. When this organ is
damaged, life may be forever altered physi-
cally, emotionally, or mentally. Sometimes the
changes are subtle or even benign, as in the
case of a Swiss stroke patient who suddenly
became obsessed with, of all things, fine din-
ing. After recovering, he quit his job as a po-
litical journalist and became a food columnist
(Regard & Landis, 1997). But all too often,
the effects are harmful and even tragic.
Scientists are developing revolutionary
new methods to help patients with brain
disease or injury and are exploring the outer
reaches of what is possible for this organ. A
few paralyzed patients have learned to con-
trol the movement of a robotic arm with just
their thoughts. Tiny electrodes attached to
brain cells that signal arm and hand move-
ments are connected to a computer, which
then translates the signals into an electronic
command conveyed to a mechanical arm.
One woman paralyzed from the neck down
was able to use the mechanical arm to
feed herself string cheese and chocolates
(Collinger et al., 2013). Other patients have
succeeded in reaching for and grasping
other objects or have controlled a computer
cursor solely by thinking of what they want
to do (Hochberg et al., 2012).
Neuroscientists in psychology and other
disciplines also study the brain and the rest
of the nervous system in hopes of gaining a
better understanding of healthy brains and
everyday behavior. They are concerned with
the biological foundations of consciousness,
perception, memory, emotion, and stress—
of everything, in fact, that human beings
feel and do. In this chapter, we will examine
4 neurons, hormones, and the Brain
nervous system as background for our later
discussions of these and other topics.
At this moment, your own brain, assisted
by other parts of your nervous system, is
busily taking in these words. Whether you
are excited, curious, or bored, your brain is
registering some sort of emotional reaction.
As you continue reading, your brain will (we
hope) store away much of the information in
this chapter. Later on, your brain may enable
you to smell a flower, climb the stairs, greet
a friend, solve a problem, or chuckle at a
joke. But the brain’s most startling accom-
plishment is its knowledge that it is doing
all these things. This self-awareness makes
brain research different from the study of
anything else in the universe. Scientists must
use the cells, biochemistry, and circuitry of
their own brains to understand the cells, bio-
chemistry, and circuitry of brains in general.
William Shakespeare called the brain
“the soul’s frail dwelling house.” Actually,
this miraculous organ is more like the main
room in a house filled with many alcoves
and passageways—the “house” being the
nervous system as a whole. Before we can
understand the windows, walls, and furni-
ture of this house, we need to become ac-
quainted with the overall floor plan.
linebacker Ted Johnson and former offensive
tackle Kyle Turley, have said they will donate their
brains to science when they die, to help achieve a
better understanding of the risks of the sport.
The brains of several deceased players
have already been examined. When safety Dave
Duerson killed himself in 2011, he left a note
asking that his brain be studied. Like Seau’s
brain and the brains of a number of other football
players who committed suicide, Duerson’s brainshowed clear evidence of CTE. Some brains have
reportedly revealed abnormalities more typically
seen in elderly Alzheimer’s patients.
Seau’s former teammate Tedy Bruschi told
ESPN recently that his friend’s death “makes
me wonder” about the risks. Yet when asked why
he continues to play, he replied that football is
his life. When you are passionate about a sport,
said Bruschi, you will play despite the risks and
dangers.