PYC3702 Chapter 2A PDF

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Chapter 2A PERSPECTIVES/MODELS OF ABNORMAL BEHAVIOR MODELS IN THE STUDY OF PSYCHOPATHOLOGY DEF Psychopathology: Clinical term meaning abnormal behavior DEF Model:

Referring to patients and mental illness is to apply a medical model (Page 33 in PB Understanding Abnormal Behavior)

A MULTIPATH MODEL OF MENTAL DISORDERS DIMENSION 1 Biological DIMENSION 2 Psychological

DIMENSION 4 Socio-cultural

DIMENSION 3 Social

1. DIMENSION ONE: BIOLOGICAL FACTORS * Includes genetics, brain anatomy, biochemical imbalance, central nervous system functioning, autonomic nervous system functioning, autonomic nervous system reactivity * Biological explanations of normal and abnormal behaviour share certain assumptions: o Physical features, susceptibility to diseases, temperaments, and ways of dealing with stress are embedded in the genes. o Human thoughts, emotions and behaviours are associated with nerve cell activities in the spinal cord and brain o Change in thoughts, emotions and behaviours is associated with a change in activity or structure, or both, of the brain Mental disorders are highly correlated with some form of brain or other organ dysfunction Mental disorders can be treated by drugs and somatic intervention

1.1 The human brain The brain is composed of millions of neurons – nerve cells that transmit messages throughout the body. Responsible for 3 functions: o Receives info from outside world o Uses the info to decide on a course of action o Implements decisions by commanding muscles to move and glands to secrete Weighs approx 3 pounds Separated by 2 hemispheres which work contra laterally – left side controls right and vice versa Right hemisphere is associated with visual spatial abilities and emotional behaviour Left side is associated with language functions for all right handed people and for most left handed people. 1.1.1 The forebrain o Controls all higher order mental functions associated with human consciousness, learning, speech, thought and memory o Contains the thalamus, hypothalamus, RAS (reticular activating system), limbic system and cerebrum  Thalamus – relay station form transmitting nerve impulses from one part of the brain to another  Hypothalamus (under the thalamus) – regulates body drives such as hunger, sex, thirst and body conditions such as temperature and hormone balance  Limbic system – involved in experiencing and expressing emotion and motivation – fear, pleasure, aggression, sexual arousal and pain  Cerebrum – largest structure in the brain and contains the cerebral cortex which covers the midbrain and thalamus 1.1.2 The midbrain and hindbrain Involved in vision (hindbrain) and hearing (midbrain) and the hindbrain in control of sleep, alertness and pain. Midbrain manufactures chemicals – serotonin, nor-epinephrine and dopamine which are implicated in mental disorders The hindbrain also manufactures serotonin and controls functions like heart rate, sleep and respiration. The RAS – a formation of nerve fibres that control bodily states such as sleep, alertness, and attention starts in the hindbrain towards the midbrain

Damage to the brain could lead to observable mental disorders General paresis results from brain damage caused by parasitic microorganisms Tumors, strokes, excessive intake of alcohol or drugs and such external trauma are also linked to cognitive, emotional and behavioural disorders

Biochemical theories The basic premise of these theories is that chemical imbalances underlie mental disorders since most bodily functions involve chemical actions. Messages travel through the brain by electrical impulses via neurons – received by dendrites and transmitted via axon terminals. Neurons do not touch – synaptic cleft between them When neurotransmitters reach the dendrites of the receiving neuron they attach to receptors and if their shapes correspond, they bind, triggering a synaptic excitation (encouragement to produce other nerve impulses) or synaptic inhibition (a state preventing production of nerve impulses) An imbalance of neurotransmitters in the brain is implicated in mental disorders Three convincing lines of evidence have contributed to the search for biochemical causes and cures: o Studies have shown that antipsychotic drugs have benefited people with schizophrenia, lithium for controlling affective disorders and tricyclics and monoamine oxidise inhibitors for depression o Biochemical studies indicate that these drugs work by either blocking or facilitating neurotransmitter activity at receptor sites o Certain chemical imbalances appear to be disorder specific, e.g. insufficient dopamine and Parkinson’s or excess of dopamine and schizophrenia. Two hypotheses: people with schizophrenia may have too many post-synaptic dopamine receptors (a structural explanation) or that their receptors may be supersensitive to dopamine Drugs used to treat depression alter nor-epinephrine and serotonin sensitivity and receptivity at the receptor sites Drugs used to treat anxiety affect receptor reactivity of GABA MAJOR NEUROTRANSMITTERS AND THEIR EFFECTS Neurotransmitter Source and function Acetylcholine (ACH) Dopamine

Endorphins

Occurs in systems that control the muscles and in circuits related to brain and memory. Reduction = Alzheimer’s Concentrated in small areas of the brain – one of which is associated with muscles. Excess dopamine = hallucinations (schizophrenia), less dopamine = Parkinson’s Found in the brain and spinal cord – suppresses pain

Gamma aminobutyric acid (GABA) Norepinephrine

Serotonin

Widely distributed in the brain. Works against other neurotransmitters, especially dopamine Occurs in the Central Nervous system – regulates mood and may increase arousal and alertness. Associated with mood and eating disorders Occurs in the brain. Works in opposition to nor-epinephrine, suppressing activity and causing sleep. Linked with anxiety disorders, mood and eating disorders.

Genetic explanations Autonomic nervous system is inherited in human beings Several researchers implicate heredity as a causal factor in alcoholism, schizophrenia and depression To show that a disorder is inherited, researchers must demonstrate that it could not be caused by environmental factors alone, that closer genetic relationships produce greater similarity of the disorder in human being and that people with these problems have similar biological and behavioural patterns Biological inheritance is transmitted by genes Genotype – a person’s genetic makeup, e.g. eye colour Phenotype – interaction between the environment and a person’s genotype, e.g. height (due to nourishment) or observable physical and behavioural characteristics Human Genome Project (HGP) To understand the impact of genes on human life Mapped out location of all genes in the nucleus of a human cell Sequenced the order of DNA chemical sub-units in each cell HGP was successful in creating a basic blueprint of the entire genetic material found in each cell in the body The human genome is composed of all the genetic material in the chromosomes of a particular organism and is the most complex instruction manual ever conceived on how the body works Pharmacogenomics – the science of understanding the correlation between a patient’s genetic makeup and his or her response to drug treatment. Biology-based treatment techniques Biology/somatic treatment use physical means to alter the patient’s physiological state and hence her psychological state Psychopharmacology/medication or drug therapy – the study of the effects of drugs on the mind and on behaviour Four large classes of medication: o Anti anxiety drugs (minor tranquilizers) – e.g. benzodiazepine( bind to receptors at the synaples and block transmission) & propanediols – calm

and reduce anxiety and for psychosomatic symptoms. Do not work for hallucinations and agitation experienced by schizophrenics. o Antipsychotic drugs (major tranquilizers) – e.g. thorazine – decreased patients interests in what is around them and reduced psychotic episodes (blocks dopamine receptors), used for schizophrenia o Antidepressant drugs (relieve depression by lifting mood) – 3 classes of medical compounds - monoamine oxidase inhibitors (MAOIs) - correct balance of neurotransmitters in the brain, tricyclics – work like MAOIs but with fewer side effects, e.g. imipramine, which is at least as effective as psychotherapy in relieving symptoms of depression , and selective serotonin reuptake inhibitors(SSRIs) – preferred choice for treating depression – inhibit the central nervous system’s neuronal uptake of serotonin – effective for treating unipolar depression o Antimanic drugs (e.g. lithium) – mood controlling medications effective for treating bipolar disorders, especially mania. Medications do not cure mental disorders but are like control measures Medications seem to be effective in treating active symptoms such as delusions, hallucinations and aggression and much less effective with passive symptoms like withdrawal, poor interpersonal relationships, feelings of alienation, etc Electroconvulsive therapy (ECT) Can be used to treat certain mental disorders – particularly depression Induces convulsions Use has declined due to potential permanent damage to the brain and ethical objections raised by detractors Psychosurgery Brain surgery performed to correct severe mental disorder Used for schizophrenia and severe depression but also for personality and anxiety disorders Multipath implications of biological explanations The multipath model assumes that majority of human diseases are multidimensional and multifactorial, caused by many genes interacting in a cellular environment of hormones, electrical signals, and nutrient supplies as well as in our physical, psychological, social and cultural environments. Most biological explanations implicitly assume a correspondence between organic and mental dysfunction with a minimal impact from environmental, social and cultural influence – one dimensional (unidirectional) and linear Disorders are seen as the result of complex interactive and reciprocal processes – diathesis-stress model holds that it is not a particular abnormality that is inherited but rather a predisposition to develop illness. Environmental forces

(stressors) may activate the predisposition resulting in a disorder. In a supportive environment, the abnormality may never materialize Gene-environment interactions appear much more complex than having a predisposition to develop a disorder. Certain genes or gene combinations may actually promote an environment likely to elicit stressors that negatively affect the individual – genes may predispose a person to seek out situations that place them at high risk of experiencing stressors that trigger the disorder, e.g. depression. Different forms of the same genes, called alleles and critical development periods in the life of an individual may determine whether, when, how and what mental disorders develop, e.g. in kids 5-20, abuse, stressful life events and depression Researcher measured the gene serotonin transporter gene in the above kids and found: o Those with two short alleles o Those with one long and one short allele o Those with two long alleles The group with two short and one short and one long allele were more likely to experience depression as adults in the were mistreated while they would be ok if not mistreated Those with the long alleles were unlikely to suffer depression even if they were mistreated Gene-environment interactions that occur at early critical periods can set the staf for later behavioural phenotypes Biochemical changes, brain activity and structural neurological circuitry often occur because of environmental influence, e.g. stress produced fear & adrenalin. Although biology influences the development of mental disorders, the environment also influences brain activity, brain circuitry and biochemical production/inhibition. (Page 36-44 in PB Understanding Abnormal Behavior)

2. DIMENSION TWO: PSYCHOLOGICAL INFLUENCES Several psychological factors are responsible for the etiology of mental disorders, e.g. conflicts in the mind, emotions, learned behaviour, and cognitions in personality formation Four major psychological perspectives in explaining abnormal behaviour: o Psychodynamic o Behavioural o Cognitive o Existential Psychodynamic models Have 2 main distinguishing features:

o View disorders as a result of childhood traumas o Traumas operate unconsciously because the experiences are too threatening for the adult to face and are therefore repressed through defense mechanisms (ego protection strategies that shelter the individual from anxiety, operate unconsciously and distort reality) causing abnormal behaviour Personality structure Id (present at birth - pleasure principle – wants, wants, wants!)), Ego (rational and realistic reality principle – controls id) and superego (moral principle, conscience – scans environment and works toward an ego ideal – pride for moral behaviour, guilt for immoral behaviour) Human instincts give rise to thoughts and actions with sex and aggression being the dominant instincts Psychosexual stages Oral – first year Anal – second year Phallic – 3/4th years Latency – 6-12 years Genital – puberty Fixation is the arresting of emotional development at a particular psychosexual stage Traditional psychodynamic therapy Psychoanalytic therapy or psychoanalysis has three main goals: 1. 2. 3. Methods of psychotherapy include: a. Free association – patients say whatever comes to mind regardless to reveal unconscious b. Dream analysis – interpretation of hidden meanings in dreams c. Analysis of resistance – patients unconsciously attempt to impede analysis, e.g. sudden change of subject d. Analysis of transference – patient applies to analyst attitudes she had towards another. Contemporary psychodynamic theories The major differences between post Freudian theories and psychoanalysis lies in the emphasis that the former placed in five areas: o Freedom of choice and future goals o Ego autonomy

o Social forces o Object relations (past interpersonal relations) o Treatment of seriously disturbed people Very few psychodynamic therapists practice traditional psychoanalysis Adler – People are not passive victims of biology, instincts and unconscious forces – stressed freedom of choice Jung – collective unconscious – humans are goal directed and future oriented Anna Freud – emphasised role, operation and importance of the ego. Ego is an autonomous component not at the mercy of the id. Erik Erikson – formulated stages of ego development from infancy to late adulthood – personality is flexible and capable of growth into adulthood Karen Horney – rejected penis envy – stressed that behavioural disorders are the result of disturbed interpersonal childhood relationships H. D. Sullivan – interpersonal theory for psychological disorders – a person’s psych functions can be understood only in the context of their social relations Heinz Kohut – narcissistic personality – study of mother to child relationships Otto Kernberg – borderline personality – difficulty in forming stable relationships Hyman Spotniz – modern psychoanalysis can be used with severely disturbed clients as new techniques do not require clients to be intellectually capable of understanding interpretations Most are more active in sessions, restrict the number of sessions, place greater emphasis on current factors and have adopted client-centred techniques Criticisms 3 major criticisms o Empirical procedures – observations done under uncontrolled conditions with great reliance on case studies o Role of female sexuality and personality drew heavy criticism – penis envy, unfavourable comparison to the male, etc o Psychoanalysis cannot be applied to a wide range of disturbed people – best suited to the well-educated people of middle and upper class who exhibit anxiety and not psychotic behaviour Behavioural models Concerned with the role of learning human behaviour 3 explanations of how learning occurs: 1. Classical conditioning paradigm Responses to new conditions are learned through association Involves involuntary responses (reflexes, emotional reactions, sexual arousal) controlled by the autonomic nervous system Pavlov – unconditioned (food) and conditioned stimulus (bell),

Conditioned response (a learned response to a previously neutral stimulus) is reinforced or strengthened when the conditioned stimulus is paired with the unconditioned stimulus

2. Classical conditioning in psych Acquisition of a phobia (an exaggerated, seemingly illogical fear of a particular object or class of objects), unusual sexual attractions and extreme emotional reactions 3. Operant conditioning paradigm An operant behaviour is a voluntary and controllable behaviour such as walking or thinking that operates on an individual’s environment Most human behaviour is operant in nature Instrumental conditioning – operant conditioning (Thorndike) Differences to classical conditioning: Classical conditioning is linked to involuntary behaviour while operant is related to voluntary – e.g. getting out of the hot sun Behaviours caused by classical conditioning are events precede the response, e.g. the aroma of coffee makes you crave a hot cappuccino while in operant conditioning behaviours are controlled by reinforcers – consequences that influence the frequency or magnitude of the event they follow, where positive consequences (e.g. feeling cool in the shade) increase the likelihood and frequency of a response and negative consequences reduce the chance of the behaviour being repeated. 4. In psychopathology Relationship between environmental reinforcers and abnormal behaviour, e.g. self-injuring behaviour like head banging in psychotic, autistic and mentally retarded children – this may be increased by reinforcing features in the environment, e.g, more attention to the child, giving her a sweet, etc Self-injurious behaviour, hallucinations and delusional statements can be developed and maintained through reinforcement.

Some forms of alcohol and substance dependence can be a result of pleasurable feelings and lowered anxieties (positive reinforcements)people experience Negative reinforcement (removal of an averse stimulus) can also strengthen and maintain unhealthy behaviours, i.e. student changes classes to avoid giving an oral presentation Behavioural methods acknowledge that people are not passive beings and have moved toward using social modelling and cognitive processes to supplement the principles of classical and operant learning models 5. The observational learning paradigm An individual can acquire new behaviours simply by watching other people perform them Vicarious conditioning/modeling - Learning by observing and imitating models No reinforcement necessary Can involve both respondent and operant behaviours In Psych Abnormal behaviours are learned in the same way as normal behaviours Exposure to disturbed models is likely to produce disturbed behaviours (James & Gilliland) 6. Criticisms of behavioural models It neglects or places a low importance on the inner determinants of behaviour Criticises the extension of conclusions drawn on animal behaviour to human beings Views people as empty organisms coz it lacks attention to human values in relation to behaviour Cognitive models Is based on the assumption that conscious thought mediates, or modifies a person’s emotional state and/or behaviour in response to a stimulus. We create our own problems and symptoms by the way we interpret events and situations so modifying thoughts and feelings is essential to changing behaviour How we interpret events is a function of our schema – a set of underlying assumptions heavily influenced by our experiences, values and perceived capabilities. Assumes causes of psychopathology are found in one of two processes: Actual irrational/maladaptive assumptions and thoughts In distortions of the actual thought process Irrational and maladaptive assumptions and thoughts

Unpleasant emotional responses that lead to anger, unhappiness, depression, fear and anxiety result from one’s thoughts about an event...