Schizophrenia

• characteristics

  • negative symptoms - behaviours inhibiting people with schizophrenia from demonstrating 'normal' behaviour such as being unable to hold conversation
  • positive symptoms - behaviours being exhibited in addition to 'normal' behaviours, if didn't have schizophrenia they wouldn't have symptom , include hallucination, delusions & disordered thinking
• positive symptoms

  • hallucinations - perceptions that are unreal , many people with schizophrenia report auditory hallucinations (hearing sounds or voices), tactile hallucinations (perceiving sensations if someone /something is touching their skin) & formication (small insects EG, spiders crawling on or under skin)
  • delusions - beliefs that are unreal , delusions of persecution (person/group etc want to hurt you), delusions of grandiosity (individual is special in some way EG powerful, special in some way)
  • disordered thinking - persons thoughts and discourse jump from topics & hard to follow
• negative symptoms

  • alogia - poverty of speech, can be loss of total speech or lack in meaning (simple, short answers can be issue)
  • anhedonia - individual doesn't react appropriately to pleasurable experiences
  • avolition - people seem to be indifferent/unconcerned of surroundings, lack of goal directed behaviour
  • flatness effect - individuals appear to have no emotion, show little or no emotional expression
  • catatonic behaviour - range from fast, repetitive, useless movements to little or no movement. Echopraxia can also occur were people mimic movements of other
• Biological explanation 1; dopamine hypothesis

  • proposes individuals with schizophrenia had too much of neurotransmitter dopamine as such they demonstrated symptoms related to high levels of dopamine, supported by Griffith (1968) induced psychosis in non-schizophrenic volunteers with drug that increases dopamine in the brain, found generally abrupt onset on paranoid delusions. Initial hypothesis identified as being too simple confirmed by administering drugs to reduce levels of dopamine had little to no effect
• dopamine hypothesis

  • complicated by discovery of several subtypes of dopamine receptor sites D1-D5 which are widely distributed in cerebral cortex & sub-cortically in limbic system. particular interest was D2 receptor, research as shown the impact of anti-psychotic drugs on this receptor as are found in subcortical regions and became main focus of dopamine hypothesis
  • revised dopamine hypothesis - limbic system has been main focus & consists of variety of subcortical structures engaged in many functions most notably emotions, memory formation. 2 main pathways include mesolimbic & mesocortical
• dopamine hypothesis

  • mesolimbic - carries signals from ventral tegmental area to nucleus accumbens, too much dopamine can cause overstimulation & positive symptoms (such as hallucinations/ delusions). Antispychotic drugs reduce dopamine transmission & such reduce positive symptoms
  • mesocortical - carries signals from ventral tegmental area to frontal lobe it's vital in emotional responses, motivation etc Davis (1991) notes too little dopamine in evident in D1 receptor
• biological explanation 1; evaluation

  • cause & effect - dopamine imbalances cause schizophrenia or schizophrenia cause dopamine imbalances, investigative techniques become less invasive & conduct research establish which comes first, PET scans aren't able to establish this
  • role of serotonin - serotonin identified as potential influence. Conventional antipsychotics traditionally work by temporarily blocking D2 receptor sites, not all with schizophrenia benefit from this. Atypical antipsychotics block D2 receptor,serotonin receptor 5-HT2A. dopamine hypothesis is wrong as cant explain sz on own
• biological explanation 2; structural abnormalities

  • Enlarged venitricals - cavities that produce & transport cerebrospinal fluid important as provide protection/buoyancy, 4 ventricles in brain = 1+2) left & right lateral ventricles between frontal,occipital & temporal lobe, 3) third ventricle between left and right thalamus, 4) fourth ventricle. Ventricles can be larger in some people than others without schizophrenia. Use of CAT scans reported ventricular size was greater in group of 58 individuals with chronic schizophrenia
• biological explanations 2; structural abnormalities

  • cortical atrophy - means loss of neurons in cerebral cortex, Cerebral atrophy can occur all over the brain or atrophy cam be focused in limited area, in the latter case it affects cognitive functions at that area of the cerebral cortex. Atrophy results in widening of the grooves covering cerebral cortex. Appears to characterise brains of 20%-35% of people with chronic schizophrenia
• Biological explanations 2; structural abnormalities

  • individuals without schizophrenia the left hemisphere is slightly larger than the right hemisphere (cerebral asymmetry), however in some individuals with schizophrenia the right hemisphere is notably larger (reversed cerebral asymmetry). Relevant when considering language function in normally found in left hemisphere so damage/deterioration in left hemisphere could lead to poverty of language (alogia) which is often seen in schizophrenia

  
• biological explanation 2; evaluation

  • cause or effect - unclear whether structural abnormalities are cause of schizophrenia or effect of having schizophrenia. Although researchers would ague they are a cause important to note environmental influences can impact brain tissue
  • not only linked to schizophrenia - Roy (1998) individuals diagnosed with bipolar disorder & schizoaffective disorder also found to have enlarged ventricles, disorders like bipolar & sz have overlapping symptoms & maybe result in similar structural abnormalities
• biological explanation 2; evaluation

  • are findings replicable - McCarley & collegues (1999) claim presence of enlarged ventricles in people with schizophrenia the most reliable findings in research come from brain scans. the link between cerebral atrophy & schizophrenia has been confirmed it has also not always been found & reproduced in studies of individuals with schizophrenia. McCarley siggests age,sex& severity of symptoms can have powerful influence on prevalent brain abnormalities
• individual differences 1; psychodynamic approach

  • schizophrenogenic mother (refrigerator mother) - the mother child relationship is one of the crucial development of schizophrenia. Concept proposes mothers of individuals with sz are overprotective & controlling but also rejecting & distant
  • regression - most adults satisfy oral desires (libido) through kissing, smoking etc however if they experience excessive amount of stress individuals may regress back to oral stage (ego defence mechanism) & causes ego to retreat to earlier stage
• individual differences 1; psychodynamic approach

  • fixation - during oral stage of psychosexual development the libido receives satisfaction from lips or mouth,the libidos urges are satisfied by feeding from mums breast. If infant receives too much /too little oral stimulation may become fixated.those with sz become fixated during first 1-2 months of oral stage
  • lose touch with reality - role of ego is to control id's impulses & balance demands of id with limitations imposed by superego, if individual regresses to point were ego didn't exist theres nothing stopping id from operating completely
• individual differences 1; evaluation

  • overlooks role of genetics - development of sz is consequence of early experience therefore therefore issue with nurture. Evidence to suggest biological factors as comes form adoption studies Heston (1966) 47 adoptees with same mother with diagnosis of sz & 50 adoptees with mother without sz. 10.6% who had biological mother with sz where diagnosed with sz, 0% of those without biological mother with sz where diagnosed with sz, suggests it could be co-current shared genes between mother and child
• Individual differences 1; evaluation

  • freudian concepts are out of date - first half of 20th century psychology was dominated by psychodynamic explanations. as century progressed psychologists were dissatisfied with unfalsified, unscientific nature. If cant show the existence of id,ego & superego should we trust these concepts to explain complex disorders schizophrenia
  • inconsostent support for schizophregenic mother - kasanin (1934), examined hospital records & found maternal overprotection in 33 out of 45 suggesting over 1/3 cases didnt have overprotective mother making it unconvincing
• individual differences 2; cognitive approach

  
• social psychological 1; dysfunctional families

  
• social psychological 1; evaluation

  
• social psychological 2; sociocultural factors

  
• social psychological 2; evaluation

  
• methods of modification 1; antipsychotic drugs

  
• methods of modification 1; evaluation

  
• methods of modification 2; CBT

  
• methods of modification 2; evaluation

  
• individual Differences 2; evaluation