Presentation on theme: "Psychological Approaches to Psychopathology"— Presentation transcript:
1 Psychological Approaches to Psychopathology Variety of approaches which make assumptions about the cause of abnormalityBiological – biological factorsCognitive – thought processes underlying the processBehavioural – learning experiences are critical in understandingabnormalityPsychodynamic – early experience and unconscious processes arethe key influences on behaviour (normal andabnormal)
2 abnormality the biological approach To understand how the biological approach views mental disorders
3 To understand how the biological approach views mental disorders Lesson objectiveTo understand how the biological approach views mental disordersNB Biological Approach is also known as the Medical Model and/or Somatic* Model* somatic = ‘of the body’Bio approach to psychopathology studies THE RELATIONSHIP BETWEEN BEHAVIOUR AND THE BODY’S VARIOUS PHYSIOLOGICAL SYSTEMSMost important is the NERVOUS SYSTEM, esp. THE BRAIN, as this is the ‘processing centre’ controlling all complex behaviour.In theory ALL BEHAVIOUR, AB/NORMAL CAN BE RELATED TO CHANGS IN BRAIN ACTIVITY.
4 Psychological disorders are physical illnesses... When the same symptoms frequently occur together, they represent a syndrome or disorder. The cause, or ‘aetiology’ may be one or more of the following:Brain injuryInfectionNeurotransmittersGeneticsThinkBING !Brain injury – hitting the head might cause psychological disorders – people who knock their heads might become ‘different people’ afterwardsInfection – infections such as syphilis can cause mental disorder type symptoms...Neurotransmitters – too much or too little of a neurotransmitter might produce disorders – high levels of dopamine are linked to schizophreniaFaulty genes might cause some diseases that have psychological effects e.g. Huntington’s disease leads to a wearing away of mental abilities
5 Brain injury Remember Phineas Gage? Accidental Brain damage can lead to psychological disorders.After the accident, Phineas Gage was described as impulsive, disordered and having a different personalitySome months after the accident, probably in about the middle of 1849, Phineas felt strong enough to resume work. But because his personality had changed so much, the contractors who had employed him would not give him his place again. Before the accident he had been their most capable and efficient foreman, one with a well-balanced mind, and who was looked on as a shrewd smart business man. He was now fitful, irreverent, and grossly profane, showing little deference for his fellows. He was also impatient and obstinate, yet capricious and vacillating, unable to settle on any of the plans he devised for future action. His friends said he was "No longer Gage.“characterized by irreverence or contempt for god or sacred principles or things; irreligious.2. not devoted to holy or religious purposes; unconsecrated; secular ( opposed to sacred).3. unholy; heathen; pagan: profane rites.4. not initiated into religious rites or mysteries, as persons.5. common or vulgar.
6 Brain damageA degeneration or malformation of brain cells can cause memory loss often present in Alzheimer’s disease.Korsakoff’s syndrome occurs when drink and drugs damage part of the brain involved in memory.What causes Korsakoff's syndrome?Korsakoff's syndrome is caused by lack of thiamine (vitamin B1), which affects the brain and nervous system. Thiamine deficiency is often seen in people who consume excessive amounts of alcohol. This is because:Many heavy drinkers have poor eating habits. Their nutrition is inadequate, and does not contain essential vitamins.Alcohol can inflame the stomach lining and impede the body's ability to absorb the key vitamins it receives.The main symptom is memory loss - particularly of events arising after the onset of the condition. Sometimes, memories of the more distant past can also be affected. Other symptoms may include:difficulty in acquiring new information or learning new skillschange in personality − at one extreme the person may show apathy (unconcern, lack of emotional reaction), or at the other, talkative and repetitive behaviourlack of insight into the condition. Even a person with great gaps in their memory may believe that their memory is functioning normallyconfabulation − inventing events to fill the gaps in memory. For example, a patient who has been in hospital for several weeks may talk convincingly about having just visited his auntie on the south coast earlier that day. This is more common in the early stages of the illness.
7 InfectionSometimes an infection that causes one illness can lead to a secondary illness that has psychological symptoms.
8 InfectionSyphilis bacterium causes a sexually transmitted disease known as syphilis.It causes short-lived sores followed by general paresis - forgetfulness, mental deterioration and delusions of grandeur and persecution.The influenza virus has been linked to schizophrenia.Brown et al (2004)found that 14% of schizophrenic cases may be linked to the foetus being exposed to the ‘flu virus in the womb during the first trimester.
9 Neurotransmitter Imbalance Certain neurotransmitters have been thought to contribute to many psychological disordersNeurotransmitters are the chemicals that carry information around the nervous systeme.g. Dopamine, Serotonin, GABA9
10 Neurons conduct pulses of electricity – Nerve Impulse. Nerve impulses are the unit of information processing in the nervous system.All aspects of human behaviour - perception, memory, language, thought, emotion, personality – are coded by patterns of nerve impulse in thenervous system.When the NI reaches the axon terminal, it finds a gap – a synapse. It cannot jump the gap.Instead, the NI triggers the release of neurotransmitter molecules, which diffuse over the post synaptic membrane of the receiving neuron.the post synaptic membrane is covered with synaptic receptors.This bonding of neurotransmitter and receptor alters the biochemical characteristic of the post synaptic membrane, allowing the NI to proceed…hopefully.
11 Neurotransmitter Imbalance Too much or too little of a particular neurotransmitter can lead to psychopathologyOne of the factors involved in schizophrenia is an excessive amount of dopamineHigh levels of serotonin have been thought be involved in the manic state of bi-polar depression.Neurotransmitters have been studied quite a bit in relation to psychology and human behavior. What we have found is that several neurotransmitters play a role in the way we behave, learn, the way we feel, and sleep. And, some play a role in mental illnesses. The following are those neurotransmitters which play a significant role in our mental health.Dopamine – correlated with movement, attention, and learning§ Too much dopamine has been associated with schizophrenia, and too little is associated with some forms of depression as well as the muscular rigidity and tremors found in Parkinson’s disease.Drugs like cocaine increase dopamine levels and can induce schizophrenia –like symptoms.Serotonin – plays a role in mood, sleep, appetite, and impulsive and aggressive behavior§ Too little serotonin is associated with depression and some anxiety disorders, especially obsessive-compulsive disorder. Some antidepressant medications increase the availability of serotonin at the receptor sites.GABA (Gamma-Amino Butyric Acid) – inhibits excitation and anxiety§ Too little GABA is associated with anxiety and anxiety disorders. Some anti-anxiety medication increases GABA at the receptor sites.11
12 GeneticsIndividuals may inherit a predisposition* to certain illnesses. These are carried on genes, through DNA, which pass from one generation to the next*PREDISPOSITION = Increased vulnerability to a particular disease based on genetic factors12
13 Genetics Every human has 46 chromosomes (DNA) divided into 23 pairs. During reproduction, 23 chromosomes from mum and 23 chromosomes from dad are combined to make an embryo (cells before a baby)13
14 GeneticsThis is how we get our characteristics from both of our parents.If a disorder is caused genetically then we would expect individuals who are closely related to be more likely to have it14
15 Genetics How do we measure this? Concordance rate: measures how often two individuals who are closely related have the same disorder.15
16 Genetics Research Twin Studies: Twins can be identical (monozygotic,MZ) orfraternal (dizygotic, DZ).Monozygotic (MZ) twins have identical DNA16
17 McGuffin et al (1996)Studied twins where one of the pair already suffered from depression.Assessed the co-twin and found…46% concordance rate for depression (MZ)20% concordance rate for depression (DZ)
18 Gottesman (1991) Meta-analysis of about 40 twin studies Found concordance rate for schizophrenia of 48% in monozygotic twins and 17% in dizygotic twins
19 Kendler, Masterson and Davis (1985) Relatives of schizophrenics were 18 times more likely to be diagnosed with schizophrenia than we would normally expect.19
20 Strengths of biological approach Techniques have shown that there are biological components. Brain scanning has improved our ability to see this.Research shows that there can be a genetic linkDrugs can work as treatment optionsWhen it explains things, it is scientificNo blameBrain imaging studies etc show how neurotransmitters can be involvedBipolar disorder, phobias, schizophrenia etc sometimes run in familiesDepression, for example, can be effectively treated with drugsIt focuses upon physical factors in the same way that medicine does for physical disorders. Genes and brain chemistry can be reliably measured and manipulated.Patients may find it reassuring that their ‘condition’ can be attributed to a physical deficiency rather than ‘something wrong with them’ as a person
21 Weaknesses of biological approach ReductionistGenetics don’t provide a complete explanation, e.g. diathesis-stressDrugs won’t work for everyoneFocus of curing symptoms, not causeMight encourage patients to be passiveTakes only the biological view, when we know that there are also environmental factors. Doesn’t paint the full pictureThis component (genetic) must interact with non-genetic environmental fators. E.g. non genetic factor could be stress, which then triggers the genetic vulnerability.This is called diathesis-stress, the interaction between nature (e.g genetic vulnerability) and nurture (stress) = depression.Drug treatments not effective for everyone. And some disorders don’t respond at all, e.g. e.g. phobias and eating disorders. Drugs are like a plaster, they treat the symptoms, but not the underlying causes.