Download Paradigms What is a paradigm? Three to consider The Genetic

1/17/2014
What is a paradigm?
Paradigms
Frameworks to consider, analyze, and
interpret psychopathology
Three to consider
• Genetic
• Neuroscience
• Cognitive - Behavioral
The Environment’s role
• Our environment, what we eat, do, and
experience, controls which and whether genes
are turned off or on and what they do
• Without the genetic capability we could never
do certain things, but without an
environmental trigger, the gene might lie
dormant, unexpressed
• A framework to think about and study any
topic
• Basic assumptions which underlie any
scientific investigation
• A perspective through which we can decide
how and what information we gather and
then, how we interpret it
The Genetic Paradigm
• Fast developing
• Loads of new information since the discovery
of DNA’s stricture (1953) and the sequencing
of the human genome (2003)
• Now we know that:
1) virtually all behavior is influenced by
genes, and
2) the environment influences how genes
are expressed
Genetic basics
• Humans have 46 chromosomes, 23 pairs
• Each chromosome contains many genes
which are composed of DNA
• We have less than 25,000 genes
• The number is unimportant
• How they are strung together (sequenced)
and how they make proteins which control
whether genes become active (gene
expression) is what counts
1
1/17/2014
The Big Point
Back to Psychopathology
• Genes and the environment interact with each
other
• As we go through our lives we encounter
certain things (i.e. stress, trauma, toxins,
exercise) which can cause certain genes to
become active or to turn off
• Genes are not destiny
• No md is controlled by one gene
• Instead they are polygenetic – influenced by a
number of genes expressing themselves as
they interact with the environment
• We don’t inherit mental illnesses
• We develop mental illnesses from the
interaction between genes and the
environment
Heritability
But don’t forget ….
The extent to which variability
in a behavior/mental disorder
in a population can be
explained by genetics
Other factors
• Shared environments – school siblings go to,
neighborhood, church, family vacations
• Nonshared environments – friends an
individual has, girl friends/boyfriends,
hobbies, extracurricular activities
especially crucial re mds
1) estimates run from 0 (genetics plays no
role – what language you speak) to 1
(genetics controls everything – tongue rolling)
2) refers only to large groups of people
(populations) not individuals
Behavior genetics
• How do our genes influence what we do?
• As stated earlier, genetics is not destiny
genotype – our total genetic potential
phenotype – what we are
subject to change depending
on our interactions with our environment
2
1/17/2014
For example, IQ in differing
environments
• If a child lives in a challenging environment
(low SES), the major factor in IQ is the
environment
• In a more stimulating environment, genetics
are more important
• Tough circumstances hurt more than good
help
Gene & Environment Interactions
• A person’s sensitivity to an environmental
event is shaped by genes
• Often an adverse reaction (depression)
requires both a genetic vulnerability and a
traumatic event
New Zealand abused children & depression
Molecular Genetics:
getting to the source
• Identifying which specific genes influence
which traits, abilities, characteristics, etc.
• Polymorphism – differences in individual
genes
• Single nucleotide polymorphisms –
differences caused by one DNA sequence
• Copy number variations – errors in copying
DNA, whether additions or deletions
Epigenetics – passing on traits without
genes
• Cross-fostered rat moms engaged in lots of
nurturing maternal behaviors, if they received
such treatment, even if they lacked the
applicable genetic marker
• And so did the next generation!
• But the affection triggered a gene which
facilitated such behavior.
It goes the other way too!
• Genes encourage the choice of certain
environments
• Reciprocal Gene-Environment Interaction
• Worse yet, these environments or behaviors
can then cause certain outcomes – like
depression or alcoholism
Genetic Paradigm Overview
• Genes in conjunction with the environment
clearly play a role in developing some mds
• But how do genes and environments do this?
• Animal studies offer clues
• How genes/environments influence the brain
shows great promise for understanding.
3
1/17/2014
Neuroscience
• Paradigm assumes that psychopathology is
caused by problems with the brain or nervous
system
• Three aspects:
1) Neurons and neurotransmitters
2) the brain, and
3) the Neuroendocrine System
Neurotransmitters
• Tiny packets of chemicals that bridge the gap
(synaptic cleft) between two neurons
• Attach to special receptors on the dendrite of
the receiving cell
• These events attempt to influence the
receiving neuron to send out its own message
(excitatory) or to refrain from sending a
message (inhibitory)
“Big” neurotransmitters
• Dopamine – involved with schiz, depression
• Serotonin – involved with depression, impulse
control, and sleep
• Norepinephrene – can cause anxiety and
stress
• Gaba – also deals with anxiety
Neurons – four components
• Dendrites receive information
(neurotransmitters)
• The cell body acts on info
• Axons
• Terminal buttons send info
(neurotransmitters)
Then what happens?
• Reuptake - Neurotransmitters can go back to
the terminal button (synaptic vesicles), or
• Reexcitation – neurotransmitter can be
expelled from receptor and then return to
excite another neuron, and
• Dispersal – enzymes can break down the
neurotransmitter and then what’s left can be
swept away by the bodily fluids
How do they cause problems?
• Too much or to little?
• Kinda, but it’s more complcated - enzymes
• If not broken down, effects can be
exaggerated
• If not produced, minimized
4
1/17/2014
Receptor troubles
• Too many – exaggerated effect – schiz &
dopamine
• To treat, use an antagonist to dampen activity
• Over-used – receptor become desensitized
• To treat, use an agonist to increase activity
The Brain
• Billions of tightly packed neurons
• Composed of two hemispheres connected by
the corpus callosum
• Four lobes within the cerebral cortex:
1) Frontal,
2) Temporal,
3) Occipital, and
4) Parietal
The Limbic System
• More subcortical structures
• Important with respect to emotions and drives
– hunger, thirst, sex, fight/flight
• Key are the hippocampus (memory) and the
amygdala (emotion, especially fear) and how
they work together
Don’t forget glial cells
• Support, nourish, and control neurons
• Improper functioning can play a role in
dementia or schiz
• New
Subcortical structures
• Beneath the cerebral cortex we find important
Parts of the brain
• Basal ganglia – parts of the brain which
together both start and stop cognitive and
motor activity
• Thalamus – relay center for most of the senses
• Brain stem – pons and medulla relay neural
activity
Brain development
• Very complicated process
• If things go wrong – problems result
5
1/17/2014
Once we find the reinforcer …
• We stop providing the reinforcement
• Or we administer punishment (time-out) to
weaken the behavior
• We reinforce desirable behaviors, by making
reinforcement contingent upon them
Systematic Desensitization
• A way to conquer unreasonable fear or
anxiety
• Two elements:
1) deep muscle relaxation, and
2) gradual exposure
• Can be either in vivo or imaginal
• Important to fade reinforcement once desired
behavior is performed consistently
How about thinking and feeling?
• Cognitive science adds treatment options
• Takes into account that we actively filter our
experiences based upon past info &
experience
• Schemas – mental structures for organizing
information about the world
New views on the Unconscious
• Cognitive scientists study the Unconscious
• But what was revealed points away from Freud’s
view
• Our brain does a lot that we aren’t aware of
• We are influenced by, monitor, and remember,
much that we do not consciously attend to
• Implicit Memory – priming and the Cocktail Party
Effect
The importance of Attention
• What, or how, we focus on in any situation is
crucial
• Anxious people focus on threatening events
• Schizophrenics can’t even focus
• The Stroop Task shows how attention can
compromised, even by emotional bias’
Cognitive Behavior Therapy
• Using cognitive insights to change behavior
• Cognitive Restructuring – changing thought
patterns
• Altering thoughts can change feelings and
behaviors
• Starts with close monitoring of
thoughts/moods
• Some are so deep-rooted they are automatic
6
1/17/2014
Beck’s Cognitive Therapy
• Underlying insight – we’re sad because of
what we distort life experiences
• Problems arise from:
1) What we attend to,
2) How we interpret it, and
3) What we remember.
The importance of Emotions
• The expression, experience, and physiology
that guide how we react to our environment
• Problems with emotion figure in most types of
psychopathology
Beck’s CBT II
• Therapy focuses on persuading p’s to change
their opinion of themselves and the way they
interpret life events
• Challenge negative thoughts and
interpretations of life events
• Beck’s CBT has been expanded in varying
directions
Emotional expression
• Schizophrenics – not enough, if any
• Panic attack- too much
• Crucial whichever paradigm we use
What emotion do want?
• Ideal affect
•
•
•
•
•
In the West, we want happiness or excitement
If we lack these, we feel bad
Leads to abuse of cocaine or amphetimines
In the East, calmness is referred
In turn, heroin is often abused
Sociocultural Influences
• Factors like gender, socioeconomic status,
ethnicity, race, and culture
• These can trigger, accelerate, or maintain mds
7
1/17/2014
Gender –the psychological aspects of
our sexuality
• Some mds effect the sexes disproportionately,
like depression, antisocial personality disorder,
or alcoholism
• What risk factors can we identify?
Culture and Ethnicity
• Some mds are found everywhere – schiz
• Others are limited to a particular culture – eating
disorders in the West, or hikikomori in Japan
• Ethnicity also can be important
• More schiz among African-Americans
• Caucasians are more likely to abuse drugs
• Further, culture may influence gene expression
Poverty
• Huge factor in mds
• Related to:
1) antisocial personality disorder
2) depression
3) anxiety
Interpersonal factors
• The quality of our relationships is key
• These include:
1) marriage
2) family
3) friends, and
4) casual acquaintances
• Could be plus (intimacy) or minus (hostility)
Family therapy
Attachment Theory
• Often crucial for many reasons
• Parenting skills – conduct disorder
• Communication, reducing criticism, education,
developing skills to cope or cure – bipolar,
schiz
• Acknowledging the problem itself – substance
abuse
• How we were nurtured in our first year of life
can have important ramifications
• Treated with sensitivity – able to form trusting
bonds as adults
• Not so lucky – likely to experience
psychological difficulties
8
1/17/2014
Diathesis-Stress:
an integrative paradigm
Diathesis-Stress II
• Merges the other paradigms
• Focuses on the interaction between a
predisposition to disease – the diathesis - and
environmental challenges – the stress
• Diathesis’ can be genetic, delivery
complications, poor nutrition, etc.
• Anything that has a deleterious effect on the
brain
• From a psychological perspective, diathesis
can be faulty schemas, excessive fears,
insecure attachment, etc.
• The stress element explains how the
predisposition turns into a md
• Consist of some adverse environmental event
such as severe trauma, loss, or even day to
day hassles
• Big point – takes both to produce md
9