Chapter 2 - Integrative Approach to Psychopathology Flashcards
Multi-dimensional Integrative Approach
Biological Dimensions - Casual factors from the fields of genetics and neuroscience
Psychological Dimensions - causal factors from behavioral and cognitive processes, including learned helplessness, social learning, prepared learning,, and unconsciousness processes.
Emotional Influences - contribute in various ways to psychopathology, as do social and interpersonal influences.
Developmental Influences - figure in any discussion of causes of psychological disorders
Genes
Long molecules of deoxyribonucleic acid (DNA) at various locations on chromosomes within the cell nucleus are inherited from your parents and your ancestors.
Nature of Genes
An average human cell has 46 chromosomes arranged in 23 pairs.
Development of the brain and body
The first 22 pairs of chromosomes
Sex Chromosome
The last pair of chromosomes determines an individual’s sex.
X Chromosomes
The last pair of chromosomes are both X chromosomes for females.
Y Chromosomes
The last pair of chromosomes have a Y chromosome from the mother and an X chromosome from the father for males.
Dominant Gene
One pair of genes that strongly influences a particular trait
[We only need one to determine eye or hair color.]
Recessive Gene
It must be paired with another (recessive) gene to determine a trait.
Polygenic
Most of our behavior, our personality, and even our intelligence are influenced by many genes, each contributing only a tiny effect, all of which, in turn, may be influenced by the environment
The same is true for psychiatric disorders
Quantitative Genetics
Basically, it sums up all the tiny effects across many genes without necessarily telling us which genes are responsible for which effects.
Molecular Genetics
It focuses on examining the actual structure of genes with increasingly advanced technologies such as DNA microarrays.
DNA microarrays
Technologies that allow scientists to analyze thousands of genes all at once and identify broad networks of genes that may be contributing to a particular trait.
Gene studies in rat pups
The absence of normal maternal behavior of “licking and grooming” prevents the genetic expression of a glucocorticoid receptor that modulates stress hormones. This means that rats with inadequate maternal care are more sensitive to stress.
The Interaction of Genes and the Environment
Eric Kandel suggested that the very genetic. Cell structure may change due to learning if genes that were inactive or dormant interact with the environment in such a way that they become active.
(In other words, the environment may occasionally turn certain genes)
This type of mechanism may lead to changes in the number of receptors at the end of a neuron, which in turn, would affect biochemical functioning in the brain.
Diathesis-Stress Model
Individuals inherit tendencies to express certain traits or behaviors, which may be activated under stress conditions.
Each inherited tendency is a diathesis, which means, literally, a condition that makes someone susceptible to developing a disorder.
Vulnerability
The tendency of the diathesis that is inherited mixed with such a life event or type of stressor.
Diathesis is genetically based and the stress is environmentally based but they must interact together to produce a disorder
Two versions of a particular gene were studied for depression.
Allele: the long allele (LL) and the short allele (SS)
Long Allele (LL)
With at least two copies of the long allele (LL), animals were able to cope better with stress than individuals with two copies of the short allele (SS)
Recorded stressful life events show in people with two S alleles, the risk for having major depression doubled if they had at least four stressful events, compared to participants experiencing four stressful events who had two L alleles.
Gene-environment correlation model
or
Reciprocal gene-environment model
Some people might have a genetically determined tendency to create the environmental risk factors that trigger a genetic vulnerability.
Example: Someone may tend to seek out difficult relationships or other circumstances that lead to depression.
Epigenetics
Genes may be turned on or off by cellular material that is located just outside of the genome and stress, nutrition, or other factors can affect this epigenome, which is then immediately passed down to the next generation and maybe for several generations.
Human Nervous System
- Central Nervous System - consisting of the brain and spinal cord
- Peripheral Nervous System - consisting of the somatic nervous system and the automatic nervous system
Neurons
Transmit information throughout the nervous system.
On average the brain uses 140 billion neurons to control our thoughts and actions.
Typical neuron
It contains a central cell body with two branches: dendrites and axons.
a.) Dendrites have numerous receptors that receive messages in the form of chemical impulses from other nerve cells, which are converted into electrical impulses
b.) Axon transmits these impulses to other neurons through connections called synapses.
Action Potential
Information that is transmitted through electrical impulses within each neuron along the axon.
Terminal Button
The end of an axon
Synaptic Cleft
The space between the terminal button of one neuron and the dendrite of another
Neurotransmitter
Biochemicals (chemicals stored in the vesicles of the terminal buttons) that are released from the axons of one neuron and transmit the impulse to the dendrite receptors of another neuron
(Excess or insufficiencies in some neurotransmitters are associated with different groups of psychological disorders)
Major neurotransmitters relevant to psychopathology
- Norepinephrine (aka Noradrenaline)
- Serotonin
- Dopamine
- Gamma-aminobutyric acid (GABA)
- Glutamate
Excitatory Neurotransmitters
They increase the likelihood that the connecting neurons will fire.
- Research showed increased levels of dopamine activity linked to schizophrenia
- Research found correlations between depression and higher levels of norepinephrine
Inhibitory Neurotransmitters
They decrease the likelihood that the connecting neurons will fire.
- Research found reduced levels of GABA associated with excessive anxiety
- Research found correlations between depression and low levels of serotonin.
Overview of the brain in two parts
- Brain stem - a lower and more ancient part of the brain handling essential functions like breathing, sleeping, and moving in a coordinated way, containing the hindbrain, midbrain, thalamus, and hypothalamus.
- Forebrain - The largest part of the forebrain is the cerebral cortex, which allows us to look to the future and plan, reason, and create. Contains the Limbic system with the hippocampus (sea horse), cingulate gyrus (girdle), septum (partition), amygdala (almond), basal ganglia, and caudate (tailed) nucleus.
Hindbrain
Regulates many automatic activities like breathing, heart pumping (heartbeat), and digestion.
It contains the medulla, pons, and cerebellum.
*Cerebellum - controls motor coordination, and recent research suggests that abnormalities in the cerebellum may be associated with autism, although the connection with motor coordination is unclear.
Midbrain
Coordinates movement with sensory input and contains parts of the reticular activating system, which contributes to processes of arousal and tension, such as whether we are awake or asleep.
Thalamus and Hypothalamus
Involved broadly with regulating behavior and emotion
Primarily functions as a relay between the forebrain and the remaining lower areas of the brain stem.
Limbic system
Regulate our emotional experiences and expressions and, to some extent, our ability to learn and to control our impulses. (also involved with the basic drives of sex, aggression, hunger, and thirst)
Limbic means border, so named because it is located around the edge of the brain’s center.
Basal Ganglia and the Caudate (tailed) nucleus
Because damage to these structures is involved in changing our posture or twitching or shaking, they are believed to control motor activity.
Cerebral cortex division
Two hemispheres:
a.) Right hemisphere
b.) Left hemisphere
The hemispheres may look alike structurally and operate relatively independently (both are capable of perceiving, thinking, and remembering) however, recent research indicates that each has different specialties.
