Psychopathology - Lecture notes section 4 PDF

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2018

Psychopathology PS111: BRAIN AND BEHAVIOUR DANIEL TONES

Introduction to Psychopathology Defining a mental disorder 

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DSM-V o Disorder occurs within individual o Goes beyond what would be culturally accepted reaction to event o Not primarily result of social deviance or conflict with society Personal distress o Part of definition o Not all involve distress (e.g. antisocial personality disorder) o Not all psychological distress related to mental disorder (e.g. grief after death of loved one) Disability o Impairment in some important area of life; social or occupational o Not all disorders involve disability (e.g. bulimia) Violation of social norms o Social norms: widely held standards defining what is considered to be normal behaviour in a particular situation  Vary across cultures and ethnic groups o Example: conversation with imaginary voices in schizophrenia o Not all disorders involve violation of social norms o Not all violations of social norms are related to a mental disorder Dysfunction o Psychological processes not functioning in a normal way

History of Psychopathology 

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Ancient times till 19th century o Early demonology  Before age of scientific inquiry all good and bad manifestations of power beyond human control were regarded as supernatural  Doctrine that evil being, or spirit can dwell within a person and control his/her mind  Treatments  Exorcism  Trephination Early biological explanations: Hippocrates (fifth century BC) o Separated medicine from religion, magic and superstition o Seizures not sacred o Brain is organ of consciousness, intellectual life and emotions o Content of dreams possibly symbolic  Three categories of mental illness  Mania  Melancholia  Phrenitis  Depends on delicate balance of four humors/fluids  Imbalance produce mental illness  Blood, black bile, yellow bile and phlegm o Treatments  Very different to exorcism  E.g. melancholia: prescribe tranquillity, sobriety, care in choosing food and drink, abstinence from sexual activity Early biological explanations: Plato (fourth century BC) o Soul as two-horse chariot  Spirit (noble emotions)  Appetite (basic drive)  Imbalance leads to mental illness Dark ages and demonology (2nd – 17th century) o Christian monasteries replaced physicians as healers/authorities on mental disorder  Church gained influence  Return to a belief in supernatural causes of mental disorders o Persecution of witches (13th century)  Witchcraft seen as heresy and denial of God Development of asylums (15th century) o Leprosariums converted to asylums  Deplorable conditions, did not lead to more humane and effective treatment Pinel’s Reforms during French Revolution o Primary figure in movement for humanitarian treatment o Begun to treat patients as sick humans rather than as beasts Moral treatment (18th century) o Based on humane psychosocial care o Derived partly from moral concerns o Close contact with attendants, who talked and read to them

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o Purposeful activities: residents led lives as close to normal as possible Robert Burton: Anatomy of melancholy – 1621 o Comprehensive treatise containing personal disclosure o Inwardly-directed anger/guilty o Alliance with sympathetic, impartial counsellor crucial Biological approaches of the 19th century o Discovery of biological origins in Paresis and Syphilis  Biological causes of types of psychopathology  Biological approaches gained credibility o Genetics: Francis Galton  Originator of genetic research with twins  Attributed behavioural characteristics to heredity  Coined term ‘nature/nurture’  Created eugenic movement in 1883 o Bloodletting: treatment for agitating behaviour o Hydrotherapy: another treatment for agitated behaviour Psychological approaches of the 18th and 19th century o Mesmer and Charcot  Many people observed to be subject of hysteria, referring to physical incapacities such as blindness or paralysis, for which no physical causes could be found  Both used a form of hypnosis to treat hysteria o Franz Mesmer  Believed hysteria caused by particular distribution of universal magnetic fluid o Jean-Martin Charcot  Hysteria problem with NS, but persuaded with psychological explanations  Developed hypnosis  Influences on Freud o Josef Breuer  Cathartic method  Treated young women’s hysteria with pseudonym ‘Anna O’  Cathartic method: ‘reprocessing’ under hypnosis  Reliving earlier emotional trauma and releasing emotional tension by expressing previously forgotten thoughts about the event  Recalling the event associated with the first appearance of that symptom under hypnosis and expression the emotion felt at the time

Stigma     

Most people do share a rather scientifically informed view o However mental illness still stigmatised A label is applied to a group of people that distinguishes individuals with mental illnesses from others (e.g. “crazy” The label is linked to deviant or undesirable attributes by society o E.g. crazy = dangerous People with the label are seen as essentially different from those without People with the label are discriminated against unfairly

Paradigms in Psychopathology What is a paradigm?    

Conceptual framework or approach within which a scientist works Often involve concept or view of human nature Profound implications on which questions scientists ask and which answers they give Proposed treatment procedures differ according to the paradigms within they are set up

Paradigms of the 20th century 

Freud: psychoanalysis o Much of human behaviour determined by forces that are inaccessible to awareness o Psychopathology results from unconscious conflicts within the individual o Three structures of the mind  Id  Present at birth, where energy comes from, which is needed to run psyche, including basic urges for food, water, elimination, warmth, affection and sex  Libido: biological and unconscious  Operates on pleasure principle, seems immediate gratification  When the id is not satisfied, tension is produced, and the id impels person to eliminate this tension  Ego  Begins to develop from the id at the end of 1st year of life  Primarily conscious  Operates on reality principle; how to deal with reality  Mediates between demands of reality and id’s demand for immediate gratification  Superego  Roughly conceived as person’s conscience  Develops during phallic stage (3-6 years), related to the Oedipus Complex  Children incorporate parental values as their own, in order to receive the pleasure of parental approval and avoid the pain of disapproval o Oedipus and Electra Complex  During phallic stage of development (3-6 years), boy falls in love with his mother  Afraid of castration by father and represses his desire and starts to identify with his father  In girls: ‘Electra Complex’; vice versa o Defence mechanisms  Un- or preconscious strategies used by the ego to protect itself from anxiety o Psychodynamic treatments  Still practiced today, but not as common  Understand early childhood experience; key relationships and patterns in current relationships  Make conscious what was repressed thus overcoming mental disorders  Free association and interpretation  Technique to help people explore their repressed and unconscious conflicts  Mostly talking about dreams which are interpreted by analyst  Defence mechanisms principle focus

Criticism  Overinterpretation of evidence generated during free association  Lack of empirical evidence  Lack of effectiveness of the technique of free associations in curing o Continuing influences  Childhood experiences shape adult personality  There are unconscious influences on behaviour  The causes and purposes of human behaviour are not always obvious Behaviourism o Observable behaviour o All behaviour acquired by simple learning processes; classical (Pavlovian) and operant (Skinnerian) conditioning o Case of Little Albert  Watson et al. used classical conditioning to evoke pathological fear within 9month-old Albert  Albert developed fear of white rats after Watson’s co-worker made a noise whenever white rat present o Extinction: when CS no longer followed by UCS o Operant conditioning  Positive reinforcement: response strengthened by pleasant effect  Negative reinforcement: response strengthened by removal of an aversive event o Modelling  Learning by watching and imitating others  Children of parents with phobias or substance abuse may acquire similar behaviour patterns, in part through observation o Behaviour therapy  Emerged in 1950s  Based on classical and operant conditioning to alter clinical problems  Systematic desensitisation  Deep muscle relaxation  Gradual exposure to a list of increasingly feared situations  Flooding/Exposure therapy in vivo or virtual reality o Limitations  Focus on behaviour, excluding cognition and emotion Cognitive therapy o The way in which people think about, or appraise situations can influence behaviour in a dramatic way o How people construe themselves and the world is a major determinant of psychological disorders o Change feelings, behaviours and symptoms by changing thoughts  Beck’s cognitive therapy  Based on negative triad (world, future, self)  Ellis’ Rational-Emotive Therapy  Sustained emotional reactions caused by internal sentences people repeat to themselves  People with psychological distress maintain irrational high demands towards themselves  Aim of REBT is to eliminate these self-defeating beliefs and reconsider irrationally high demands o

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Current paradigms in psychopathology 

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Genetic paradigm o Gene: carriers of genetic information o Gene expression: the process by which genes make proteins that in turn make up the body and brain o Psychopathology is polygenetic o Heritability  Extent to which variability of a trait or disorder can be accounted by genetic factors  0.0 to 1 (based on similarities between MZ and DZ twins or adoption studies) o Shared environment/nonshared environment factors just as important as genes in genetic research o Behaviour genetics  Studies of the degree to which genes and environmental factors influence behaviour; mostly twin and adoption studies  Genotype  Total genetic makeup of individual  Phenotype  Totality of observable physical and behavioural characteristics  Product of interaction between genotype and environment  E.g. intelligence o Molecular genetics  Studies to identify particular genes and their function  Identify differences in sequence and structure  Polymorphisms  Difference in DNA sequence on a gene that occurs in the population  Single nucleotide polymorphism  Most common type  Copy number variations  Abnormal copy of one or more sections of DNA within gene(s) o Gene environment interaction  Caspi et al. (2003) – large sample of children followed from age 3 to age 26  Assessment of the 5-HTT gene and childhood maltreatment  People with the short allele combinations of the 5-HTT gene AND suffered maltreatment  Lead to increased risk of major depressive disorder o Reciprocal gene-environment interaction  Genes may predispose us to seek out certain environments that then increase the risk for developing a disorder Neuroscience paradigm o Concerned with ways in which the brain contributes to psychopathology o Key neurotransmitters implicated in psychopathology  Agonist/antagonist  Drug that works on the neurotransmitter’s receptor to either stimulate or dampen the activity of that neurotransmitter  Second messengers  Released by receptor, when a cell is firing more frequently  Helps neuron adjust receptor sensitivity when it has been overly active o Prefrontal cortex  Involved in behaviour organisation  Poor executive function involved in most mental disorders

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 PFC helps regulate amygdala Limbic system  Support visceral and physical expression of emotion  Amygdala  Area for attention on emotionally salient stimuli and memory  Assumed to play major role in anxiety disorders Two stress axes  HPA axis (hypothalamic-pituitary-adrenocortical axis)  Hypothalamus – releases corticotropin releasing factors (CRF), which communicate with the pituitary gland  Pituitary gland – releases adrenocorticotropic hormones, which travel via blood to adrenal glands  Adrenal cortex – releases cortisol (stress hormone)  HPA axis central to body’s response to stress  Operates rather slowly; about 10 mins  Autonomic nervous system  Sympathetic/parasympathetic  Quick operation, without conscious awareness

Factors that cut across the paradigms 

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Sociocultural factors o Gender  Some disorders affect men and women differently o Socioeconomic status  Poverty as major influence on psychological disorders o Cultural and ethnic factors  Number of disorders observed in diverse parts of the world  Other disorders appear to be specific to particular cultures  Culture influences how symptoms are expressed Interpersonal factors o Quality of relationships  Family and marital relationships  Social support  Amount of casual social contact  Couples therapy  People in distressed marriage 2 to 3 times as likely to experience a psychological disorder  Working with both partners to reduce relationship distress  Family therapy  Problems of the family impact on the members and vice versa  Family therapy often interprets specific symptoms of a family member as a problem of the family system  Interpersonal therapy  Emphasise importance of current relationships and how problems in these relationships can contribute to psychological problems  Attachment theory  Attachment styles; how we relate to our closest friends and relatives Diathesis-stress model o Links genetic, neurobiological, psychological and environmental factors o Interaction between diathesis (predisposition) and stress (environmental/life disturbances)

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Both necessary to develop disorder

Mood Disorders 

Disabling disturbances in emotions o From the extreme sadness and disengagement of depression to the extreme elation and irritability of mania  Two broad types  Depressive disorders  Bipolar disorders

Depressive disorders 

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Cardinal symptoms o Profound sadness and/or… o Inability to experience pleasure Cognitive symptoms o Self-recrimination, focused on deficits o Difficulty to concentration Physical symptoms o Fatigue and low energy o Sleep: too much or too little, difficulty falling or staying asleep o Change in appetite; weight loss/weight gain o Decrease in sexual interest o Psychomotor retardation or agitation Initiative disappears o Social withdrawal o Neglect of appearance Major Depressive Disorder o Diagnosis (DSM-V)  At least 5 symptoms; must include depressed mood or loss of interest/pleasure; additional symptoms  Time criterion: symptoms must be present for at least 2 weeks o Episodic disorder; present for a period then clear o Recurrence  2/3 of affected people experience at least one more episode  Mean: four episodes  With every new episode, the risk for a further episode increases by 16% Dysthymia o Chronic depressive disorder  Chronically depressed for more than half of the time and at least two additional symptoms  For at least two years  Mean duration: more than 5 years o Symptoms  Do not clear for more than 2 months at a time  Milder than MDD but not less severe (it is chronic) Epidemiology o Lifetime prevalence o High comorbidity with:  MDD = 16%  Anxiety disorders  Dysthymia = 2.5%  Substance related o Onset disorders  Late teens/early twenties  Sexual dysfunction o Gender differences  Personality  After age 15 MDD is twice as common in women disorders  No gender differences in childhood o

Increasing prevalence across 20th century

Bipolar disorders 

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Three forms o Bipolar I o Bipolar II o Cyclothymic disorder  All three defined by manic symptoms  Differ in severity and duration Termed bipolar o Most people who experience mania, will also experience depression o An episode of depression IS NOT REQUIRED for Bipolar I but IS REQUIRED for Bipolar II Mania o State of intense elation and irritability accompanied by other symptoms that affected people may get  Louder and make incessant stream of remarks  Flight of ideasBi  From sociable to intrusive  Excessively self-confident  Oblivious to consequences of their behaviour  Stop sleeping, stay energetic o Manic episode lasts at least one week and causes significant distress or functional impairment Hypomania o Hypo = under o Less distinct symptoms o Hypomanic episode: symptoms last at least four days o Clear changes in functioning, but no impairment  No serious problems  More social, flirtatious, energised and productive o No psychotic symptoms Diagnosis of Bipolar I Disorder (DSM-V) o A manic episode at least once in a lifetime  Distinctly elevated or irritable mood  Abnormally increased activity and energy o Time criterion: over a week o Does not have to experience current symptoms o High rates of recurrence  More than 50% experience 4 or more episodes o More severe form of mental illness than MDD  High rates of inability to work, suicide, other medical conditions Diagnosis of Bipolar II Disorder (DSM-V) o At least one major depressive episode AND o At least one episode of hypomania Diagnosis of Cyclothymic Disorder (DSM-V) o Symptoms last at least 2 years among adults o Frequent but mild symptoms of depression, alternating with mild symptoms of mania Epidemiology o Life time prevalence o Comorbidity  Bipolar I = 1%  2/3 also suffer from  Bipolar II = 0.4-2% anxiety disorders  Cyclothymia = 4%  1/3 also suffer from o Onset substance abuse  In more than 50% of people, before age 25 o Gender  Equally often in women and men but women experience more depressive episodes

Aetiology of mood disorders  

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Aetiology = study of cause/origination of a disorder Diathesis-stress model o Neurobiological factors  Genetic factors  Neurotransmitters  Differences in brain structure and/or function  Neuroendocrine o Psychosocial factors Genetic factors o Twin studies reveal heritability of  37% for MDD  93% for bipolar o Specific genes/regions  Inconcsistent results, often non-replications  Probably it is rather a set of genes than a single one o Polymorphisms consistently related to the vulnerability to develop MDD  Polymorphism of the serotonin transporter gene  Influence serotonin function  Polymorphism of the DRD4.2 gene  Influence on dopamine function Neurotransmitters o Absolute level of serotonin, dopamine and norepinephrine in synaptic cleft; too high or too low  Depression: low norepinephrine, dopamine and serotonin  Mania: high norepinephrine and dopamine, low serotonin  Research on antidepressants DO NOT support hypothesis of absolute level of neurotransmitters  Antidepressants rapidly change NT levels, effect on symptoms occurs with a lag of around 2 weeks (sometimes even transient worsening of symptoms within first few days)  Metabolites of serotonin are not different in people with MDD in terms of absolute levels o Alternative explanation: sensitivity of receptors  Sensitivity of serotonin receptors  People with insensitive receptors experience depressive symptoms as levels of serotonin drop  Studies with tryptophan as major precursor of serotonin  Depletion of tryptophan causes temporary depressive symptoms among people WITH history of depression  Depletion of tryptophan causes NO depressive symptoms amoung people WITHOUT history of depression Differences in brain structures and/or function o Functio...