Abnormal Psychology Notes Week 2- Chapter 3: Models of Abnormality The Biological Model -Adopts a medical perspective -Reductionistic-Mechanistic -Disease focused -Main focus is that psychological abnormality is an illness brought about by malfunctioning parts of the organism -Typically point to problems in brain anatomy or brain chemistry-abnormality brought by some malfunctioning parts of the organism-brain anatomy and brain chemistry -other parts of the body may play a role, but not oftenHow Do Biological Theorists Explain Abnormal Behavior?-Brain Anatomy -The brain is compose of ~100 billion nerve cells (called neurons) and thousands of billions of support cells (called glia) -Within the brain, large groups of neurons form distinct areas called brain regions -neurons make up part of the brain -may ask about neurons on test-the biological model directs attention to difference in brain anatomy- difference in different brain regions -Brain anatomy and abnormal behavior -Clinical researchers have discovered connections between certain psychological disorders and differences in specific brain areas -Example: Enlarged ventricles in schizophrenia; plaques between neurons in AD; Huntington’s disease and changes in basal ganglia and cortex -individuals who tried to study if there are brain differences in the structure of the brain(structural differences)-the structure of the brain- a scientist would lookat the brain-this person would have delusions-so they would compare this persons brain to another persons brain-look for things that are obvious-Alzheimers look like neurons get plaque on them- structural things of having a disorder -doesn’t necessarily distinguish between cause and effect Schizophrenia- the space between the ventricles look different -(Very Basic) Brain Chemistry -Information is communicated throughout the brain in the form of electrical impulses that travel from one neuron to one or more others -An impulse is first received by a neuron’s dendrites, travels down the axon, and is transmitted through the nerve endings to other neurons -Functional-introducing the idea of actually trying to treat something -brain functions different- different parts function different than other parts that have the disorder -The brain communicates through impulses-Hundreds of neurons exist in brain and communicate with each other -synaptic space- the way these neurons communicate deals with what happens in that space- release NT -Some NT activate (excitory) or deactivate (inhibitory) the neuron -Don’t change the number of neurons or the health of the neuron all they change is affecting the release or uptake of NT-Brain Chemistry -Neurons do not actually touch each other; they are separated by a space (the synapse), across which a message moves -When an electrical impulse reaches a nerve ending, the ending is stimulated to release a chemical, called a neurotransmitter (NT), that travels across the synaptic space to receptors on the dendrites of neighboring neurons -some MTs tell receiving neurons to “fire”; other NTs tell receiving neurons to stop firing -Brain Chemistry and abnormal behavior -Researchers have identified dozens of NTs-Examples: serotonin, dopamine, and GABA-Studies indicate that abnormal activity in certain NTs can lead to specific mental disorders -For example: depression has been linked (often indirectly) to low activity of serotonin and norepinephrine -some medications increase the effect by increasing certain NT-> SSRI- keeps serotionin in synaptic cleft -the biological model cease -Someone accidently found these results of medications that were used for other causes help mental disordersSources of Biological Abnormalities- Genetics -Abnormalities in brain anatomy or chemistry are sometimes the result of genetic inheritance -Studies suggest that inheritance plays a part in mood disorder, schizophrenia, and other mental disorders -appears that in most cases several genes combine to produce our actions and reactions-Genes that contribute to mental disorders -May be intraindividual mutations -May be inherited after a mutation in the family line -May be the result of normal evolutionary principles -Got shared genes, but no understanding that the genetic structure can change after birth- can change when still a fetus- the older you get the more set your genetic structure is- can have mutations- can start with the same genes, but don’t end with the same genesSources of Biological Abnormalities- Evolution -Evolutionary theorists argue that human reactions and the genes responsible for them have survived over the course of time because they have helped individuals thrive and adapt -Example: The fear response -In today’s world, however, those genes and reactions may not be so adaptiveSources of Biological Abnormalities- Viral Infections-Another possible source of abnormal brain structure or biochemical dysfunction is viral infections leading to intraindividual mutation -Example: Schizophrenia and prenatal viral exposure -Interest in viral explanations of psychological disorders has been growing in the past decade -Example: Depression and virus exposure and inflammatory processes -notion of fundamental germ theory disease-Prenatal viral exposure -Children that were born during a high influenza time- mother was more exposed to the Flu- have a higher chance of getting schizophreniaBiological Treatments-Biological practitioners attempt to pinpoint the physical source of dysfunction to determine the course of treatment-Three types of biological treatment:-Drug Therapy-most common-most have the effect of manipulating the effect of a NT -Electroconvulsive therapy (ECT)-Psychosurgery -Drug Therapy:-1950’s= advent of psychotropic medications -greatly changed the outlook for a number of mental disorders -Four major drug groups:-Antianxiety drugs (anxiolytics; minor tranquilizers)-Antidepressant drugs-Antibipolar drugs (mood stabilizers)-Antipsychotic drugs -Electroconvulsive therapy (ECT):-Used primarily for depression, particularly when drugs and other therapies have failed -this treatment is used on tens of thousands of depressed persons annually -Psychosurgery (or neurosurgery):-Historical roots in trephination -1930’s= first lobotomy -Much more precise today than in the past -Considered experimental and used only in extreme cases Assessing the Biological ModelStrengths:-Enjoys considerable respect in the field -Constantly produces valuable new information