Chapter 4 Neurons, Hormones, and the Brain 137who could not hold a steady job or stick to a plan.
His employers had to let him go, and he was re-
duced to exhibiting himself as a circus attraction.
There is some controversy about the details
of this sad incident, but many other cases of brain
injury, whether from stroke, disease, or trauma,
support the conclusion that most scientists draw
from the Gage case: Parts of the frontal lobes
are involved in social judgment, rational decision
making, and the ability to set goals and to make
and carry through plans. Like Gage, people with
damage in these areas sometimes mismanage their
finances, lose their jobs, and abandon their friends.
Interestingly, the mental deficits that characterize
such damage are accompanied by a flattening out
of emotion and feeling, which suggests that normal
emotions are necessary for everyday reasoning and
the ability to learn from mistakes (H. Damasio et al.,
1994; A. Damasio, 2003; Levenson & Miller, 2007).
Watch the Video Thinking Like a Psychologist:
The Pre-Frontal Cortex: The Good, The Bad, and
The Criminal at mypsychlab
The frontal lobes also govern the ability to
do a series of tasks in the proper sequence and to
stop doing them at the proper time. The pioneer-
ing Soviet psychologist Alexander Luria (1980)
studied many cases in which damage to the frontal
lobes disrupted these abilities. One man Luria
observed kept trying to light a match after it was
already lit. Another planed a piece of wood in the
hospital carpentry shop until it was gone and then
went on to plane the workbench.accident drove an inch-thick, 3 1/2-foot-long iron
rod clear through the head of a young railroad
worker named Phineas Gage. As you can see in
the photos on this page, the rod (which is still on
display at Harvard University, along with Gage’s
skull) entered beneath the left eye and exited
through the top of the head, destroying much of
the prefrontal cortex (H. Damasio et al., 1994).
Miraculously, Gage survived this trauma and, by
most accounts, he retained the ability to speak,
think, and remember. But his friends complained
that he was “no longer Gage.” In a sort of Jekyll-
and-Hyde transformation, he had changed from
a mild-mannered, friendly, efficient worker into
a foul-mouthed, ill-tempered, undependable lout
On the far left is a recent digital reconstruction of Phineas Gage’s skull, showing the trajectory of the iron rod that
penetrated his brain. The photos in the center and on the right show reconstructions of the interior of the skull from
the front and from above. The colors indicate the different fiber pathways that were probably affected, including
white-matter pathways between the frontal cortex and other brain parts (Van Horn et al., 2012). After the accident,
Gage’s behavior and personality were altered dramatically, and scientists today understand why: The rod passed
through an area of the prefrontal cortex associated with emotional processing and rational decision making.
Mike Baldwin/CartoonStock Ltd. CSL