Transcript Etiological theories - Central Connecticut State University

Carolyn R. Fallahi, Ph.D.
Portions of this power point taken
from Mash & Wolfe’s Instructor’s
Manual.
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Etiology = causal explanation
In order to study abnormal behavior, we
need to understand all the possible
influences.
– Case study: Mark
– Poor academic performance
– Frustration and depressive symptoms
– Motivational problems
– Parental issues
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 There
usually is no “single” cause for a
psychiatric disorder.
• Biological explanation
• Psychological explanation
• Environmental explanation
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Taken from Mash & Wolfe (2005)
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 Because
to understand abnormal
behavior, we must view it in relation to
what is considered normative.
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Taken from Mash & Wolfe (2005)
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Genetic theories
Neurobiological theories
Emotional theories
Behavioral and Cognitive theories
Societal, Cultural, and Family theories
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 Gregor
Mendel
 Genetic Theories
 Phenotype
 Huntington’s Disease
 Single transmission
vs. multifactorial
transmission
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The continuum: main street America, a
quirky personality, hours cleaning your
apartment, medication and treatment of
OCD?????
The dimensional approach.
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Concordance
rates = if 1 twin has a
disorder, what is the probability
that the second twin will have the
disorder?
Fraternal vs. identical twins.
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Type of illness
Autism
Identical twins
(%)
60
Fraternal twins
(%)
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Schizophrenia
40
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Depression
50
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Bipolar Disorder
40
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Concordance Rates for Mental Illness in Twins
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 Are
they unmodifiable?
 Immediate early genes (genes that
produce proteins that enable the brain
to respond quickly to a changing
environment)
 Complex organic chemicals (class of
genes that stimulate the production of
certain proteins).
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 Neural
Plasticity and the Role of
Experience
The brain is organized in a
hierarchical process
What about early experiences? Do
they make a difference? The answer
is YES!
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 Genetic
Contributions:
• All traits = nature versus nurture.
• There are very few disorders that
result from ONLY a genetic
explanation.
• Genes and psychopathology = a small
contribution!
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 Brain’s
neurons make connecticuts at a
very fast pace – birth through 24 months.
 What does deprivation do to a child? The
case of Genie.
 Yet… brain plasticity. The cases of Brandi
Binder and Antonio Battro (3 and 5 years
old).
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 Does
brain damage cause ADHD and
autism? NO.
 The role of neurochemistry.
 1960’s = research team exposed rats to
an enriched environment. What
happened?
• Increased levels of acetylcholine.
• Heavier cerebral cortices.
• Larger cell bodies in cortical neurons.
• Increased neuronal connections and branching.
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 The
work of David Snowden & his nun
study.
 Impoverishing experiences, e.g. Hubel &
Wiesel and kittens.
 What if the environment causes early
stress? What does that research say?
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 Neurobiological
Contributions:
• different areas of the brain regulate
different functions and behaviors
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 Endocrine
system
 The brain stem
 Thalamus
 Hypothalamus
 Cerebellum
 Forebrain
 Limbic system
 Hippocampus, cingulate gyrus, septum
and amygdala
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 Caudate
nucleus
 Limbic system
 Basal ganglia
 Cerebral cortex
 2 hemispheres – left and right
 Corpus collosum
 Occipital lobes
 Parietal lobes
 Temporal lobes
 Frontal lobes
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 At
what age is the brain finished
developing?
 Pruning – use it or lose it.
 The role of myelination.
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
Neurobiological contributions
• hypothalamic-pituitary-adrenal (HPA) axis
• neurotransmitters make biochemical connections
between different parts of the brain; those most
commonly implicated in psychopathology include
seratonin, benzodiazepine-GABA, norepinephrine,
and dopamine
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Neurotransmitter
Benzodiazepine-GABA
Dopamine
Norepinephrine
Serotonin
Normal Functions
Reduces arousal and moderates
emotional responses, e.g. anger,
hostility, and aggression. Linked
to feelings of anxiety and
discomfort.
May act as a switch that turns
on various brain circuits,
allowing other neurotransmitters
to inhibit or facilitate emotions
or behavior. Is involved in
exploratory, extroverted, and
pleasure-seeking activity
Facilitates or controls emergency
reactions and alarm responses.
Plays a role in emotional and
behavioral regulation
Plays a role in information
processing and motor
coordination. Inhibits children’s
tendency to explore their
surroundings. Moderates and
regulates a number of critical
behaviors, e.g. eating, sleeping,
and expressing anger.
Implicated role in psychopathology
Anxiety disorder
Schizophrenia
Mood disorders
ADHD
Not directly involved in specific disorders (acts to
regulate or modulate behavioral tendencies)
Regulatory problems, e.g. eating and sleeping
disorders.
OCD
Schizophrenia and mood disorders
Mash & Wolfe (2005, p. 41)
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 Emotional
Influences:
• emotions tell us what to pay attention
to and provide motivation for action
• children may have difficulties in
emotion reactivity or emotion
regulation
• temperament shapes the child’s
approach to the environment and vice
versa
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 Behavioral
and Cognitive Influences:
• classical conditioning
• Operant conditioning
• social learning
• social cognition
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Ecological
models
•describe the child’s environment as a series of
nested and interconnected structures
•Urie Bronfenbrenner
Ecological – a theory by Urie Bronfenbrenner (1979)
Microsystem
Mesosystem
Exosystem
Macrosystem
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
Evolution and Attachment
• attachment theory emphasizes the evolving childcaregiver relationship, which helps the child to
regulate behavior and emotions, especially in
conditions of threat or stress
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 The
Family and Peer Context
• increasingly, the study of individual factors
and the study of the child’s context are
being seen as mutually compatible and
beneficial to both theory and intervention
• family system theorists study children’s
behavior in relation to other family
members
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