Chapter 2 Flashcards
multi-dimensional integrative approach
Biological dimensions include causal factors from the fields of genetics and neuroscience. Psychological dimensions include causal factors from behavioral
and cognitive processes, including learned helplessness,
social learning, prepared learning, and even unconscious
processes. Emotional influences contribute in a variety of
ways to psychopathology, as do social and interpersonal influences. Finally, developmental influences figure in any
discussion of causes of psychological disorders.
do phobias have genetic links?
Do you ever feel queasy at the sight
of blood? If so, chances are your mother, your father, or
someone else in your immediate family has the same reaction. In one study, 61% of the family members of individuals with this phobia had a similar condition
what plays a substantial role in the development of many disorders
emotions
developmental critical period
s. Thus, at certain times we may
enter a developmental critical period when we are more or
less reactive to a given situation or influence than at other
times.
As you can see, finding the causes of abnormal behavior
is a
complex process. Focusing on biological or behavioral
factors would not have given us a full picture of the causes
of Judy’s disorder; we had to consider a variety of other influences and how they might interact. We now examine the
research underlying the many biological, psychological,
and social influences that must be considered as causes of
any psychological disorder
genes
Genes are long molecules of deoxyribonucleic acid
(DNA) at various locations on chromosomes within the cell
nucleus. Physical characteristics are determined—or at least
strongly influenced—by our genetic endowment
. Other factors in the environment influence our physical appearance,
however
To some extent, our weight and even our height are
affected by nutritional, social, and cultural factors. Consequently, our genes seldom determine our physical development in any absolute way. They do provide some boundaries
to our development. Exactly where we go within these
boundaries depends on environmental influences.
but some characteristics are determined strongly by genes like
hair and eye color. also some rare diseases like huntington’s disease
dominant and recessive genes and when does gene dominance occur?
A dominant gene is one of a pair of genes that strongly
influences a particular trait, and we need only one of them
to determine, for example, our eye or hair color. A recessive gene, by contrast, must be paired with another (recessive) gene to determine a trait. Gene dominance occurs
when one member of a gene pair is consistently expressed
over the other (for example, a browneyed gene is dominant over a blueeyed gene). When we have a dominant
gene, we can predict fairly accurately how many offspring
will develop a certain trait, characteristic, or disorder,
depending on whether one or both of the parents carry
that dominant gene.
quantitative genetics and molecular genetics
Quantitative genetics basically sums up all the tiny effects across many genes without necessarily telling us which genes are responsible for
which effects. Molecular genetics focuses on examining the
actual structure of genes with advanced technologies such
as DNA microarrays; these technologies allow scientists to
analyze thousands of genes at once and identify broad
networks of genes that may be contributing to a particular
trait (Kendler, 2011; Plomin & Davis, 2009). Such studies
have indicated that hundreds of genes can contribute to
the heritability of a single trait
It has also become clear that adverse life events such as
a “chaotic” childhood can overwhelm the influence of genes
(Turkheimer, Haley, Waldron, D’Onofrio, & Gottesman,
2003). For example
one member of a set of twins in the
Lyons et al. (2009) study showed marked change in cognitive abilities if his or her environment changed dramatically
from the other twin’s because of some stressful event such
as death of a loved one
For psychological disorders, the evidence indicates
that genetic factors make some contribution to all disorders but account for less than half of the explanation
If one of a pair of identical twins has schizophrenia, there
is a lessthan50% likelihood that the other twin will
also (Gottesman, 1991). Similar or lower rates exist for
other psychological disorders
linkage study
In linkage studies, scientists study individuals who have
the same disorder, such as bipolar disorder, and also
share other features, such as eye color; because the location of the gene for eye color is known, this allows scientists to attempt to “link” known gene locations with the
possible location of a gene contributing to the disorder
diathesis-stress model
For years, scientists have assumed a specific method of interaction between genes and environment. According to this
diathesis–stress model, individuals inherit tendencies to express certain traits or behaviors, which may then be activated
under conditions of stress (see l Figure 2.2). Each inherited
tendency is a diathesis, a condition that makes someone susceptible to developing a disorder. When the right kind of life
event, such as a certain type of stressor, comes along, the disorder develop
explain the diathesis-stress model in regards to judy’s situation
s. For example, according to the diathesis–stress
model, Judy inherited a tendency to faint at the sight of blood.
This tendency is the diathesis, or vulnerability. It would not
become prominent until certain environmental events occurred. For Judy, this event was the sight of an animal being
dissected when she was in a situation in which escape was not
acceptable. The stress of seeing the dissection under these
conditions activated her genetic tendency to faint. Together,
these factors led to her developing a disorder. If she had not
taken biology, she might have gone through life without ever
knowing she had the tendency, at least to such an extreme,
although she might have felt queasy about minor cuts. You can
see that the diathesis is genetically based and the stress is environmental but that they must interact to produce a disorder
We might also take the case of someone who inherits a vulnerability to alcoholism.
During college, both this person and
a friend who lack the tendency engage in extended drinking
bouts, but only the individual with the socalled addictive
genes begins the downward spiral into alcoholism. Having a
particular vulnerability doesn’t mean you will develop the
associated disorder.
the smaller the vulnerability,
the greater the the life stress required to produce the disorder; conversely,
with greater vulnerability, less life stress is required.
chemical transporter
The
investigators also identified the genetic makeup of the individuals and, in particular, a gene that produces a substance
called a chemical transporter that affects the transmission of
serotonin in the brain. Serotonin, a neurotransmitter, is particularly implicated in depression and related disorders.
caspi longitudinal study- pg 66
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gene-environment correlation model
This is the gene–environment correlation model or reciprocal gene–environment model (Jaffee, 2011; Kendler,
2011) (see l Figure 2.4). Some evidence indicates that it applies to the development of depression, because some people
may tend to seek out difficult relationships or other circumstances that lead to depression
McGue and Lykken
(1992) have even applied the gene–environment correlation
model to some fascinating data on the influence of genes on
the divorce rate. F
For example, if you and your spouse each
have an identical twin, and both identical twins have been
divorced, the chance that you will also divorce increases
greatly. Furthermore, if your identical twin and your parents
and your spouse’s parents have been divorced, the chance
that you will divorce is 77.5%. Conversely, if none of your
family members on either side has been divorced, the probability that you will divorce is only 5.3%.
This is the extreme example, but McGue and Lykken
(1992) demonstrated that the probability of your divorcing
doubles over the probability in the population at large if your
fraternal twin is also divorced and increases sixfold if your
identical twin is divorced. Why would this happen?
To the
extent it is genetically determined, the tendency to divorce is
almost certainly related to various inherited traits, such as
being highstrung, impulsive, or shorttempered, that make
someone hard to get along with (Jockin, McGue, & Lykken,
1996). Another possibility is that an inherited trait makes it
more likely you will choose an incompatible spouse. To take
a simple example, if you are passive and unassertive, you may
well choose a strong, dominant mate who is also impossible
to live with. You get divorced but then find yourself attracted
to another individual with the same personality traits, who is
also impossible to live with. Some people would simply attribute this kind of pattern to poor judgment. Nevertheless,
there’s no doubt that social, interpersonal, psychological, and
environmental factors play major roles in whether we stay
married, and it’s quite possible that our genes contribute to
how we create our own environment.
familial influence on the likelihood of psychiatric disorders- pg 68
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But
chaotic early environments can override genetic factors and
alter neuroendocrine function to increase the likelihood of
later behavioral and emotional disorders (Dickens et al.,
2011; OuelletMorin et al., 2008).
How does this work?
It seems that genes are turned on or
off by cellular material that is located just outside of the genome (“epi,” as in the word epigenetics, means on or around)
and that stress, nutrition, or other factors can affect this epigenome, which is passed down to the next generation and
maybe for several generations (Arai, Li, Hartley, & Feig, 2009;
Mill, 2011). The genome itself isn’t changed, so if the stressful
environment disappears, eventually the epigenome will fade.
That is, it seems that environmental manipulations, particularly early in life, may do much to override the genetically influenced tendency to develop undesirable behavioral and
emotional reactions (Mill
neuroscience
Knowing how the nervous system and, especially, how the
brain works is central to any understanding of our behavior, emotions, and cognitive processes. This understanding
is the focus of neuroscience. To comprehend research in this field, we first need an overview of how the brain and the
nervous system function.
epigenetics
he study of factors other than inherited DNA sequence, such
as new learning or stress, that alter the phenotypic expression of genes
The brain uses an average of
140 billion
nerve cells, called neurons, to control every thought and action. Neurons transmit information throughout the nervous system
Excesses or insufficiencies in some neurotransmitters are associated with different groups of psychological disorders. For example, r
reduced levels of GABA were
initially thought to be associated with excessive anxiety
(Costa, 1985). Early research (Snyder, 1976, 1981) linked
increases in dopamine activity to schizophrenia. Other
early research found correlations between depression and
high levels of norepinephrine (Schildkraut, 1965) and, possibly, low levels of serotonin (However, more recent research indicates that these
early interpretations were too simplistic. We return to the
subject of neurotransmitters shortly
endocrine sytem - pg 72-73
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Some studies have found, for example, that depressed
patients may respond better to an antidepressant medication if it is administered in combination with a thyroid
hormone (Nierenberg et al., 2006). This interdisciplinary
area of research is termed
psychoneuroendocrinology and is
a growing subfield
One of the functions of the parasympathetic system is to
balance the sympathetic system. In other words, because
we could not operate in a state of hyperarousal and preparedness forever, the parasympathetic nervous system
takes over after the sympathetic nervous system has been
active for a while, normalizing our arousal and facilitating
the storage of energy by helping the digestive process
HPA axis
When athletes say their adrenaline was really
flowing, they mean they were highly aroused and up for the
competition. The cortical part of the adrenal glands also produces the stress hormone cortisol. This system is called the
hypothalamic–pituitary–adrenocortical axis, or HPA axis; it
has been implicated in several psychological disorders we
discuss in this text.
One brain connection implicated in some psychological
disorders involves the hypothalamus and the endocrine system. The hypothalamus connects to t
to the adjacent pituitary
gland, which is the master or coordinator of the endocrine
system (see l Figure 2.10). The pituitary gland, in turn, may
stimulate the cortical part of the adrenal glands on top of the
kidneys.
As we noted previously, surges of epinephrine tend
to
energize us, arouse us, and get our bodies ready for threat
or challenge.
brain circuites
There are thousands, perhaps tens of thousands, of these brain circuits,
and we are just beginning to discover and map them
(Arenkiel & Ehlers, 2009). Neuroscientists have identified
several neural pathways that seem to play roles in various
psychological disorders (Fineberg et al.,
Research on neurotransmitter function focuses primarily
on what happens when activity levels change. We can study
this in several ways. W
We can introduce substances called agonists that effectively increase the activity of a neurotransmitter by mimicking its effects; substances called antagonists
that decrease, or block, a neurotransmitter; or substances
called inverse agonists that produce effects opposite to those
produced by the neurotransmitter.
By manipulating the production of a neurotransmitter in different parts of the brain,
we can
learn more about its effects
This information seems to support a biological cause for
OCD. You might think there is no need to consider social or
psychological influences here. But Insel and other neuroscientists interpret these findings cautiously
First, this case
involves only one individual. Other individuals with the
same lesion might react differently. Also, brainimaging
studies are often inconsistent with one another. Sometimes
pinpointing the increased or decreased activity is difficult
because brains differ in their structure. Also, the orbital
frontal cortex is implicated in other anxiety disorders and
maybe other emotional disorders (Gansler et al., 2009;
Goodwin, 2009), so the damage in this area of the brain
may just increase negative affect more generally rather than
OCD specifically
To take a
simple analogy, if you were late for class and began running, massive changes would occur throughout your body
and brain.
n. If someone who did not know that you had just sprinted to class then examined you with brain scans, your brain functions would look different from those of the brain of a person who had walked to class. If you were doing well in the class, the scientist might conclude, wrongly, that your unusual brain function “caused” your intelligence
psychosurgery- pg 79
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monkey gaba experiment- pg 80
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learned helplessness
which occurs
when animals encounter conditions over which they have
no control (Maier & Seligman, 1976). If rats are confronted with a situation in which they receive occasional
foot shocks, they can function well if they learn they can
cope with these shocks by doing something to avoid them
(say, pressing a lever). But if the animals learn their behavior has no effect on their environment—sometimes they
get shocked and sometimes they don’t, no matter what
they do—they become “helpless”; in other words, they give
up attempting to cope and seem to develop the animal
equivalent of depression.
positive psychology
Consider an example:
In a study by Levy, Slade, Kunkel, & Kasl (2002), individuals
between ages 50 and 94 who had positive views about themselves and positive attitudes toward aging lived 7.5 years
longer than those without such attitudes. This connection
was still true after the investigators controlled for age, sex,
income, loneliness, and physical capability to engage in
household and social activities. This effect exceeds the 1 to
4 years of added life associated with other factors, such as
low blood pressure, low cholesterol levels, and no history of
obesity or cigarette smoking. These results have been
strongly supported in more recent studies (Steptoe & Wardle,
2012). Studies such as this have created interest in a new
field of study called positive psychology, in which investigators explore factors that account for positive attitudes and
happiness (Diener, 2000; Ly
The basic idea in all Bandura’s work is that
a careful
analysis of cognitive processes may well produce the most
accurate scientific predictions of behavior. Concepts of
probability learning, information processing, and attention
have become increasingly important in psychopathology
According to the concept of prepared learning,
, we
have become highly prepared for learning about certain types
of objects or situations over the course of evolution because
this knowledge contributes to the survival of the species
An example of implicit memory at
work is the story of Anna O., the classic case first described
by Breuer and Freud
to demonstrate the existence of the unconscious. It was only after therapy that
Anna O. remembered events surrounding her father’s death
and the connection of these events to her paralysis. Thus,
Anna O.’s behavior (occasional paralysis) was evidently
connected to implicit memories of her father’s death. Many
scientists have concluded that Freud’s speculations on the
nature and structure of the unconscious went beyond the
evidence, but the existence of unconscious processes has
since been demonstrated, and we must take them into
account as we study psychopathology
flight or fight response
The alarm reaction that activates during potentially lifethreatening emergencies is
called the flight or fight response. If you are caught in
ocean currents, your almost instinctual tendency is to
struggle toward shore. You might realize rationally that
you’re best off just floating until the current runs its course
and then, more calmly, swimming in later. Yet somewhere,
deep within, ancient instincts for survival won’t let you relax, even though struggling against the ocean will only wear
you out and increase your chance of drowning
affect
. A related term is affect, which usually refers to the momentary emotional tone that accompanies what we say or do. For example, if you just got an
A on your test but you look sad, your friends might think
your reaction strange because your affect is not appropriate to the event. The term
mood and emotion on pg 86
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Emotion is composed of three related components
behavior,
physiology, and cognition—but most emotion scientists
tend to concentrate on one component or another (see
l Figure 2.16).
Emotion scientists who concentrate on behavior think that basic patterns of emotion differ from one
another in fundamental ways;
for example, anger may differ
from sadness not only in how it feels but also behaviorally
and physiologically
true or false, a btter social life helps u live longer
true
conclusgion page 94
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