CHAPTER OUTLINE
I.
FOUNDATIONS OF NEUROPSYCHOLOGY
What is neuropsychology and how did it develop?
Neuropsychology is the subfield of psychology whose goal is to explore and understand the
relationship between brain processes, human behavior, and psychological functioning.
Neuropsychologists are interested in how brain processes and disruptions of those
processes affect a wide range of human abilities, including cognitive functioning, motor
functioning, emotional functioning, and social functioning. They are also interested in how
dysfunctions in the brain relate to changes in personality and to psychological disorders.

Experimental neuropsychologists conduct research on how the human brain controls
and organizes various parts of complicated mental activities.

Clinical neuropsychologists try to understand the problems that appear in people.
A. A Brief History of Neuropsychology
For centuries philosophers and scientists have speculated about the role of different
brain areas in different psychological functions.
1. In the early 1800s the brain was viewed as a single organ with no part more
important than any other in the control of mental life.
2. Franz Gall countered this and argued correctly that particular brain areas
controlled particular aspects of mental life. This position is called localization of
function. However, in his approach called phrenology, he also mistakenly
argued that:
a) Brain areas grew with use, and corresponding bumps in the skull
developed.
b) Each area and bump was associated with certain personality traits. So, a
person’s psychological makeup could be known by feeling the bumps on a
person’s skull.
3. In the 1860s Paul Broca reestablished the notion of localization of function with
his studies of brain damage in the left frontal lobes and resulting language
problems.
a) His patient, Tan, had suffered a stroke (cerebrovascular accident, or
CVA), causing permanent damage to the brain. It left him unable to say
anything but the word tan, which became the staff’s nickname for him.
Despite his speech difficulties, Tan could apparently understand language,
because he easily followed verbal commands.
b) An autopsy of Tan’s brain showed a small lesion, or area of damage, in the
left frontal lobe. Not long afterward, Broca requested an autopsy on
another patient who had had language problems similar to Tan’s and
discovered a brain lesion in the same place as Tan’s.
B. Modules and Networks
1. The modularity view holds that the brain is organized into discrete regions called
modules, each of which performs its own unique kind of analysis on the
information it receives.
a) A module does not control a function, but as part of a team or network
provides a necessary piece that allows some particular function to occur.
(1) Each brain function is a result of a different combination of modules.
b) A disconnection syndrome occurs when various intact modules in a
network are, for some reason, prevented from interacting with each other.
A syndrome is a pattern of symptoms, and in this case it occurs when
II.
various modules in a network, though themselves intact, are prevented
from interacting.
(1) For example, in alexia without agraphia, the visual processing of
words is disconnected from the brain regions that are needed to
understand the meaning of words. So, the person can write words,
but cannot read them.
C. Lesion Analysis
In lesion analysis, neuropsychologists examine the results of brain damage.
1. They study localization of function: whether people with brain damage in the
same areas also have similar functional deficits.
2. They try find out exactly which function has been damaged.
a) They look at a complex mental task, such as doing math, and try to identify
all the different tasks the brain must combine to do math.
b) Then they try to determine which of these tasks are separate or dissociated
from the others.
(1) One way to do this is to study which tasks are affected by which
kinds of brain damage.
D. Neuropsychological Assessment
1. To decide when a person has problems related to brain functioning,
neuropsychologists administer a neuropsychological assessment in which they
give patients a large number of tests designed to assess a wide range of mental
functions.
a) In some cases they use individualized assessments uniquely tailored to the
patient’s specific problems.
b) In other cases, a set of standardized tests is used. The set consists of tests
that are designed to complement one another and to address all aspects of
psychological functioning.
(1) Examples of tests in the set are the Halstead-Reiran Battery, the
Wechsler Adult Intelligence Scale, and the Luria-Nebraska
Neuropsychology Battery.
c) Most clinical neuropsychologists start with the standard set, then
administer additional tests that are relevant to the particular case.
2. Like other types of tests, many factors, such as age, education, and cultural
background, can affect a person’s performance.
a) Because of this, test results are compared to norms, or established averages,
which are based on the results of thousands of people of similar, age,
education, and cultural background, but with no known brain damage.
3. A large part of training for clinical neuropsychologists involves learning about
neuropsychological tests and how to administer, score, and interpret them.
E. Training for Neuropsychology
Neuropsychologists typically train in graduate school and obtain a Ph.D. in clinical
psychology with special focus in neuropsychology. After completing internships and
obtaining licenses to practice, many clinical neuropsychologists work closely with
medical doctors to diagnose and manage people with brain problems, often in
hospitals or other health care settings. Experimental neuropsychologists are usually
professors at universities, where they teach and conduct research.
MECHANISMS OF BRAIN DYSFUNCTION
What are the main causes of brain damage and dysfunction?
A. Cerebrovascular Accidents
Cerebrovascular accidents (strokes) are the result of a loss of blood supply to some
part of the brain. The result is death of brain tissue in that area and impairment of
whatever functions that brain area provides.
1. Strokes are the third leading cause of death in the United States.
2. Strokes usually involve little or no pain, because there are no pain receptors in
the brain.
3. Recovery from stroke depends on many factors, including quality and speed of
medical treatment, where and how large the stroke is, the health of the remaining
blood vessels and brain tissue, and what kinds of recovery programs are
undertaken after the stroke.
B. Traumatic Brain Injury
Traumatic Brain Injury (trauma) is a sudden impact to the brain caused when the
person’s head is struck by some object or when the head suddenly moves or stops
moving, as when the head is thrown against some unmoving surface.
1. Trauma occurs because the brain is not firmly attached to the skull. It floats in
cerebrospinal fluid. So, when there is sudden movement, the brain bounces
around, bumping against bone and damaging nerve fibers.
2. The amount of damage depends on the amount of force involved in the trauma.
3. Damage is often more widespread than with stroke and harder to pinpoint.
C. Neurodegenerative Diseases
Neurodegenerative diseases cause neurodegeneration, the gradual process of cell
damage in the brain.
1. Each type of neurodegenerative disease affects a particular type of brain cell or
cells in a particular part of the brain, causing them to be the first to stop working.
Therefore, the pattern of symptoms can usually be identified by tests and can
lead to specific diagnoses.
a) The most prominent diseases are Alzheimer’s disease, Parkinson’s disease,
and Huntington’s disease. But many kinds of neurodegeneration are caused
by infections, nutritional deficiencies, or genetic abnormalities.
III. NEUROPSYCHOLOGICAL DISORDERS
What disorders can be caused by brain damage or dysfunction?
Syndromes seen in patients who have suffered brain dysfunction are referred to as
neuropsychological disorders.
A. Amnestic Disorders
Amnestic disorders involve problems with memory loss, often referred to as amnesia.
Many people consult neuropsychologists for evaluation because of concern about
memory. People rely so heavily on memory that any threat to it can be very upsetting,
and people tend to interpret almost any deficit as being related to memory.
1. Brain damage can affect the ability to create new long-term memories.
a) H.M.’s surgery to stop epileptic seizures removed parts of his temporal
lobes, including the hippocampus, resulting in anterograde amnesia, the
inability to form new memories of anything—events, vocabulary, time
passing, and so on.
(1) Many of H.M.’s other mental capacities remained intact, including
language, object recognition, thought and reasoning, sociability, and
so on.
2. Amnestic syndromes can also be caused by brain infections like herpes
encephalitis, by strokes, and by Alzheimer’s disease.
3. Damage to the medial dorsal region of the thalamus can result in anterograde
amnesia.
Korsakoff’s syndrome is a deficiency of thiamine (vitamin B1) caused by
inadequate nutrition or alcoholism that leads to the death of nerve cells in
this region.
(1) Not only does anterograde amnesia occur, but in addition people with
Korsakoff’s syndrome are prone to confabulation—to believe that
they had experiences that they have not actually had.
Consciousness Disturbances
Consciousness disturbances are when problems in the brain impair people’s ability to
be conscious or to be accurately aware of the world around them.
1. The reticular formation, or reticular activating system (RAS), normally serves
to increase and decrease arousal in the rest of the brain, and helps create daily
cycles of wakefulness and sleep.
a) Severe damage results in an unconscious state known as a coma.
b) Lesser amounts of RAS damage may result in a persistent vegetative state
(PVS), during which wake and sleep cycles seem to be intact and automatic
movements occur. However, though brain activity may be evident, patients
remain unaware of their environment.
c) Chances for recovery are often poor when there is significant damage to the
RAS.
2. Disruptions in the functioning of both sides of the cerebral cortex can affect
consciousness.
a) The most common cause is drug abuse (alcohol or sleeping pills), but fever,
seizures, chemical imbalances in the blood, hormonal disorders, and
infections that have spread to the blood can also affect the cerebral cortex.
3. A key feature of people with delirium is the rise and fall of consciousness—the
alternation between impaired and abnormally elevated levels of consciousness
over time.
a) These people display impairments in many mental functions, usually
including poor memory, poor attention, and disorientation. They may also
suffer from hallucinations and agitation.
b) Common causes include fever, poisons, infections that have reached the
bloodstream, and side effects of medication.
c) Delirium is usually not permanent and usually goes away when the
underlying medical cause is corrected.
d) Neuropsychological testing is difficult. Often no pattern is apparent—
everything may look impaired.
4. Some disorders of consciousness involve the nature or content of consciousness.
a) In anosognosia, which means absence of knowledge of disease, a person
may have no awareness that there is anything wrong with him or her.
(1) It is particularly likely after damage to the right side of the brain.
(2) It is relatively common, occurring in more than 25 percent of all
stroke victims.
(3) Anosognosia may fade over time or persist. When it persists, it
impairs patients’ cooperation with rehabilitative treatments.
Thinking Critically: Can Someone Be Partially Paralyzed and Not Know It?
Anosognosia is unawareness of one’s physical or mental problem. It was first
described in relation to hemiparesis, a weakness or partial paralysis that affects just
one side of the body. Skeptics have argued that anosognosia reflects not true
unawareness, but instead an unconscious mental process similar to the ego defense
mechanism called denial.
1. What am I being asked to believe or accept?
a)
B.
C.
D.
Countering the skeptics, others contend that the brain damage that causes
hemiparesis may also damage the parts of the brain that would allow a person to
know that something is wrong.
2. Is there evidence available to support the claim?
If anosognosia is a defense mechanism, it would operate in a general way to
deny all upsetting deficits. Evidence suggests that some hemiparesis patients are
aware of certain deficits.
Anosognosia occurs more often after right hemisphere damage than left
hemisphere damage. If it were a defense mechanism, damage to either side or
particularly to the left hemisphere which affects the right side should result in
denial.
Anosognosia has been shown to occur even when there is no threat of permanent
paralysis, if the right hemisphere is “turned off” by an anesthetic.
3. Can that evidence be interpreted another way?
It is difficult to directly compare what patients are experiencing at the time that
the left and right hemispheres are actually anesthetized, because people who
have the left hemisphere “turned off” cannot use speech. Perhaps there is
anosognosia because there is enough distress to motivate denial, but people
cannot talk about it.
Families of patients suffering from hemiparesis who showed anosognosia
reported that they were most likely to cope with stress through denial before the
damage, suggesting that denial of hemiparesis is just an exaggeration of an
established coping tendency.
4. What evidence would help to evaluate the alternatives?
Family report studies may be affected by retrospective bias. That is, once they
know that their relative is denying hemiparesis, family members may be more
likely to recall similar episodes of denial and to forget about other episodes when
the patient coped in other ways.
A prospective study, in which a large group of people have their stress-coping
tendencies assessed and then are contacted regularly for many years, would
support the defense mechanism hypothesis if those who were most likely to use
denial also were the ones most likely to display anosognosia following a stroke.
5. What conclusions are most reasonable?
Some people who suffer neurological deficits may use denial or other defense
mechanisms, but evidence suggests that many cases of anosognosia reflect a true
lack of awareness of such problems.
Perceptual Disturbances
Perception involves the recognition, interpretation, and understanding of sensory
information in order to make sense of the world. Perceptual functions depend on the
operations of specific brain regions. Damage to our perceptual systems can result in
perceptual disturbances.
1. Visual information travels from the eyes to the thalamus, then to particular areas
of the occipital lobe of the cerebral cortex, where it is analyzed further. From
there it is sent along two separate but parallel pathways where specialized
analyses occur that result in different visual perceptions.
a) The pathway leading toward the ventrolateral temporal lobes (on the sides
of the head) is called the “what” system because the regions along this
pathway help people to decide what they are seeing.
(1) Damage to this system causes visual agnosia. People with this
condition can see objects, describe them, and draw them, but they no
longer know what the objects are based on their appearance. They
E.
F.
have lost the ability to link visual images of the objects to the part of
the brain where that knowledge is stored.
(a) Visual agnosia may apply to everything a person sees or just to
certain categories of objects. In prosopagnosia a person can no
longer recognize any faces—even his or her own face.
b) The pathway leading toward the parietal lobe (near the top of the head) is
called the “where” system because it processes information about the
location of objects and where those objects are in relation to one another.
(1) Damage to this system may cause simultanagnosia, a condition in
which a person can see parts of a scene, but has trouble perceiving the
entire scene.
(2) Damage to a different area of the parietal lobes may cause
hemineglect, a condition that involves difficulty seeing, responding
to, or acting on information coming from the right, or more often, the
left side of the world. The side that is neglected is usually opposite to
the side where the damage is located.
(a) Often hemineglect cannot be explained as a lack of sensation;
rather, it’s a problem of attention. People with hemineglect, in a
way, lose the concept of “leftness” or “rightness.”
Focus on Research: Studying Hemineglect
Proving that hemineglect is not simply a sensory problem can be tricky because, in
many cases, the brain damage that caused it also caused a loss of sensation from the
same side. Also, most tests rely on sensory responses. It is difficult to rule out sensory
problems if tests use sensations to test for them.
1. What was the researchers’ question?
If hemineglect is truly a problem with understanding that a side of space exists,
then this problem should persist even if the scene is just imagined and not
viewed directly.
2. How did the researchers answer the question?
Patients with right hemisphere lesions that resulted in left-sided hemineglect
were shown parts of ambiguously shaped stimuli and had to judge whether or not
the stimuli were the same or different. However, to “see” the whole image, they
had to imagine what it must have looked like in the “mind’s eye.”
3. What did the researchers find?
Left hemineglect patients were able to determine when stimuli were different
when the right sides were different. But they could not detect differences when
the left sides were different.
4. What do the results mean?
Because the stimuli were not viewed directly, the results cannot be explained by
assuming that patients just received sensations from one side of space. This study
showed that hemineglect was not simply due to a sensory problem.
5. What do we still need to know?
There are different types of hemineglect produced by damage in different parts
of the brain. Thus it is not clear if the patients with parietal lobe damage in this
study are representative of all hemineglect patients. Also, it is not clear if the
same results would occur with other sensations like touch or sound.
Linkages: Language Disorders and the Brain
When there is disruption of brain areas involved in language, specific aspects of
language involving reading, speaking, writing, or understanding will fail. These
deficits are called language disorders, or aphasias.
1.
G.
H.
Most aphasias result from damage to the left side of the brain caused by stroke or
trauma, but sometimes they are caused by gradual frontotemporal degeneration
(FTD). If FTD is focused on language-related brain regions, the result is a
condition called primary progressive aphasia.
2. Broca’s area of the brain is vital to the ability to translate thoughts into words or
writing that will be clear and meaningful.
a) In Broca’s aphasia, individuals lose language fluency. They can no longer
smoothly and easily express themselves. Their vocabulary becomes limited
to concrete nouns and verbs, and they leave out more abstract terms and
parts of speech like adjectives or adverbs.
(1) Mistakes made in naming objects are called paraphasias. In Broca’s
aphasia, they tend to be phonemic paraphasias, or errors in the way a
word should sound; for example, calling a pen a “peb.”
(2) People with Broca’s aphasia may also have difficulty understanding
what they see and hear.
3. Wernicke’s area is involved in the ability to understand the meaning of sensory
information.
a) In Wernicke’s aphasia, individuals have difficulty understanding what
they read or what others are saying. These individuals can still speak
fluently and effortlessly, but what they say is not normal.
(1) Semantic paraphasias occur when the individual uses words that have
the wrong meaning; for example, calling a pen a “book.”
(2) People with Wernicke’s aphasia tend to use lots of adverbs, adjectives
and articles, but few nouns and verbs. So, their speech does not have
a lot of content and can sound very disorganized. Unfortunately, they
do not recognize that their speech is abnormal and so become upset
when others do not understand or respond to them correctly.
4. People with right hemisphere damage can also have language problems. In
aprosodia, people may lose the ability to use tone of voice to express meaning
or to understand other’s vocal tones.
a) Damage to the right frontal lobe can result in expressive aprosodia, in
which the individual speaks only in dull monotones but may still be able to
understand and use cues from another’s tone of voice.
b) Damage to the right temporal and parietal regions may result in receptive
aprosodia, in which the individual can use the correct tone of voice when
speaking but has difficulty understanding the meaning of another’s tone of
voice.
Movement Disorders
A network of special brain systems control learned motor skills by instructing the
brain’s motor control centers to make the movements needed for each action sequence.
Damage to this network results in some form of apraxia, or movement disorder, a
condition in which learned motor skills are disrupted.
1. In ideational apraxia, the individual movements needed to perform a task are all
correctly executed, but in the wrong order.
2. In ideomotor apraxia, the sequence of movements is correct, but there are
difficulties in performing the skilled movements.
a) In one type of ideomotor apraxia, individuals may use a body part in place
of a tool because they appear to have forgotten how to use a tool they once
used with ease.
Dementia
In dementia, wakefulness and alertness remain normal, but many other mental
functions are impaired. People diagnosed with dementia must have developed a
notable impairment of memory along with some other significant psychological
dysfunction, like impaired perceptual, language, or motor functioning. Usually
dementia is gradual, progressive, and irreversible.
1. Mild cognitive impairment (MCI) may precede some kinds of dementia. In
amnestic MCI, a person displays below-average memory skills on tests but
shows no other deficits and may have adapted well enough to the memory loss
that daily functioning has not been disrupted.
2. The most common cause of dementia is Alzheimer’s disease. About 13 percent
of people over sixty-five suffer from Alzheimer’s disease. The percentage of
people with Alzheimer’s disease doubles about every five years after the age of
sixty.
a) Alois Alzheimer in 1907 described the two brain abnormalities associated
with this disease:
(1) Degenerated nerve cells twist into misshapen tangles.
(2) Clumps of proteins deposits, called amyloid plaques, lie around the
outside of the dead and dying nerve cells.
b) The anatomical basis of Alzheimer’s disease involves neurons that use the
neurotransmitter acetylcholine, particularly in the parietal and medial
temporal lobes on both sides of the brain.
(1) Because the parietal lobes are important for locating objects in space,
Alzheimer’s patients may have difficulty with spatial tasks and
navigating their environment.
(2) Because the parietal lobes are involved in language, anomia may
develop. This is a condition in which it becomes hard to name
objects, even if the objects are familiar.
(3) The left parietal lobe is also involved in learned motor skills, so
apraxia may develop.
(4) The medial temporal lobes contain the hippocampus, so Alzheimer’s
patients become unable to form new memories, though old ones
usually remain accessible until the disease has progressed further.
(5) Because the temporal lobes are also important for the interpretation of
visual sensation, visual agnosia, the inability to recognize objects,
may develop.
3. Vascular dementia is brought about by restrictions in the supply of blood to the
brain.
This often happens gradually, as small injuries to brain tissue accumulate.
a) Vascular dementia symptoms usually differ from those of Alzheimer’s
disease.
(1) There is memory loss and difficulty in remembering recent events.
Because the hippocampus is usually intact, new memories can still be
formed, but there is difficulty in retrieving these memories.
4. It is important to conduct proper testing to identify exactly what form of
dementia a person has because new medications can stop or slow the progression
of certain dementias.
5. The appearance of dementia may be delayed or prevented in those who spend
their lives engaged in stimulating mental activity, interactions with friends, and
healthy eating and exercise.
KEY TERMS
An activity based on the key terms could be used to introduce students to search engines like
PsycINFO or PsycARTICLES. This could be done as an in-class demonstration or as an
assignment.
Alzheimer’s disease (p. 658)
amnestic disorders (p. 645)
anterograde amnesia (p. 646)
Broca’s aphasia (p. 654)
cerebrospinal fluid (p. 644)
cerebrovascular accident (stroke) (pp. 638, 642-644 and 645)
confabulation (p. 647)
consciousness disturbances (p. 647)
delirium (p. 648)
dementia (p. 657)
Korsakoff’s syndrome (p. 647)
language disorders (aphasias) (p. 654)
lesion (p. 639)
movement disorders (apraxias) (p. 656)
neurodegenerative disease (pp. 644-645)
neuropsychological assessment (p. 641)
neuropsychology (p. 636)
perceptual disturbances (p. 651)
reticular formation (p. 647)
traumatic brain injury (trauma) (pp. 644-645)
vascular dementia (p. 658)
Wernicke’s aphasia (p. 655)