S2W11Disord Flashcards
Cognitive disorders vs. disorders with cog. features
Cognitive Disorders (learning, memory, perception, problem solving)
Amnesia
Delirium
Dementia
Parkinson’s
Disorders with cognitive features (cognitive problems not primary feature):
Schizophrenia
Depression
Addiction
Parkinson’s hallucinations
16-40%
Result of medication that stimulates dopamine in Substantia Nigra
Also believed to be intrinsic to the disease through impairments of sensory processing.
Parkinson’s depression
25-50%
Understandable reaction.
Can occur 3 years prior to onset (potential predictor?)
Contributed to thinking that depression is accompanied by an allostatic state (biological state of stress) that accelerates disease in the brain
Parkinson’s & Dopamine
Parkinson’s results in dopamine deficiency.
Dopamine pills developed.
L-dopa – first drug developed taken as pill and converted to dopamine by neurons.
L-dopa increases dopamine release in all axons (those deteriorated and normal ones).
Alternates between high and low levels of release.
Doesn’t replace other depleted transmitters.
Doesn’t slow the continuing loss of neurons.
Side effects: restlessness, low blood pressure, repetitive movements and hallucinations and delusions
Parkinson’s & Schizophrenia
Drugs that increase dopamine help Parkinson’s but can cause psychosis.
Drugs that decrease dopamine should help psychosis.
Side effects similar to Parkinsons (motor problems)
High doses of recreational drugs over long periods cause psychosis (raise dopamine)
Anti-psychotic drugs developed that alleviate psychosis by blocking dopamine receptors
Dopamine Hypothesis
Dopamine receptors too sensitive – messages sent too often and too easily
Parkinson’s patients – not often enough.
Antipsychotics block dopamine receptors
Schizophrenia and Cogniton DSM
No explicit mention of cognitive deficits.
Two present for 1-month:
1) Delusions
2) Hallucinations
3) Disorganised Speech
Disorganised or catatonic behaviour
Negative symptoms (e.g. avolition)
Features of Schizophrenia
Positive symptoms (excess of normal functions)
Delusions, hallucinations, disorganised speech, disorganised or catatonic behaviour
Negative symptoms (reduced normal functions)
Flattened affect, alogia (poverty of speech), avolition (apathy)
Cognitive problems are related to schizophrenia
Some memory
Attention
Perceptual-motor
Executive Functioning
Language
Hallucinations
Delusions
Cognitive Theories
Theories centre around:
Attentional processes
Attributional/Information Processing
Theory of Mind
Attentional Processes Schizophrenia
Inability to associate relevant events or irrelevant associations.
Reflect inability to focus on relevant environmental aspects (underattention)
Or overattend to irrelevant aspects.
Deficits in orienting response (response to environmental change)
Skin Conductance to simple tones – schizophrenics less sensitive.
Highly distractible on cognitive tasks:
Sustained Attention, Selective Attention, Divided Attention.
Attributional and Information Processing Schizophrenia
Attribute negative events to external causes.
Excessively stable and global attributions to negative life events.
Attribute positive events to internal causes.
Explains reports of persecution in sufferers
Bentall & Kaney (1989) Stroop Schizophrenia
Emotional Stroop Task
Name the colours of words
Words related to negative affect, paranoia or neutral
Response times for Paranoid words slower
Processing bias schizophrenia Morrison (2001)
Bias labelling cognitive intrusion as threatening
Leads to negative mood and arousal that cause more intrusions.
Freeman et al (2002) Persecutory Delusions (Formation)
Hallucination/delusion with no obvious explanation
Arousal
Search for meaning
Incooperates belief about self and the world (biased)
Selection ofexplanation
Threat belief
Freeman et al (2002) Persecutory Delusions (Maintenance)
Delusional distress
Anxiety, depression create bias toward negative thinking
Discard disconfirmatory evidence
Obtain confirmatory evidence
Reinforcement of threat belief
Social factors such as isolation
Jumping to conclusions bias
Red and blue beads in a jar.
300 in each.
One with more red one with more blue.
Schizophrenics jump to conclusions earlier on and get it wrong.
Theory of Mind Schizophrenia
Deficits in Theories of Mind
Ability to understand our own and others mental states.
Sufferers have deficit in ability to infer beliefs/intentions of others
Jokes involving inferring the mental state of others more difficult to understand
Frith & Corcoran (1996)
TOM
Six stories to schizophrenics.
First order (character has false belief about world)
Second order (character has a false belief about the belief of another character)
Types of story (circumstantial, deception)
Asked one memory question and one question about inferring mental state of others.
Patientes with paranoid delusions impaired on mental state questions.
Patients with behavioural signs impaired on mental state questions, but difficulty associated with memory impairment.
CBT schizophrenia
Challenging negative beliefs and biases that maintain psychotic thinking.
interpretation bias leads to safety behaviours that lead to more hallucinations
CBT aims to generate acceptable explanations.
Good outcomes.
Reduction in positive symptoms that are long-lasting.
Reattribution Therapy
Help patients reattribute paranoid symptoms to normal daily events.
Patients challenged by:
Monitoring frequency of delusional beliefs
Generating alternative explanations
Creating behavioural experiments that allow for reality testing.
Verbal challenge often enough
Addiction
Produces dopamine that leads to people wanting to do it again.
Behavioural or chemical based.
Interference with everyday functioning: Substance Abuse Disorder.
Behavioural (e.g. gambling)
Neurochemical (e.g. drugs)
Both increase dopamine activity.
Also direct effect on dopamine in some drugs
Twin studies and addiction
Strong influence of genetics.
Few genes specific to addiction, but number associated with different disorders.
One gene controls variation in types of dopamine receptor (short or long).
Long less sensitive so substances are less reinforcing.
Stronger craving to make up for short fall in reinforcement.
Another gene controls COMT (breaks down dopamine).
If this gene is active it breaks down dopamine more quickly so r
Leads to impulsivity and risk-taking.
Cognitive Deficits of Addiction
Impulsivity and risk-taking involve decision-making.
Direct effects of particular substances on cognition:
Language, memory and perceptual motor: alcohol/drugs
Hallucinations/delusions caused by drugs.
May also be cognitive problems that facilitate and maintain the addictive behaviour indirectly (false beliefs about effects)
