Psychology and neuroscience Flashcards
Why are post-mortem studies used to measure brain function?
Useful for ascertaining anatomical information
However limited FUNCTIONAL value (the brain is dead so we can’t measure how it worked while living)
What are “In Vitro” studies of brain function?
Study of living neurons in isolation e.g. in a tissue culture or tissue slice
Provides clearer info of how living neurons function, but limited information about how this translates into behavioural outputs
What are “In Vivo” studies of brain function?
Study of intact and living brains
Underpinned by information gained from post-mortem and in vitro studies, we can use these methods together to get a full picture of the neurological basis of a behaviour
What are the positive symptoms of schizophrenia?
Additional feelings/behaviours not found in typical individuals
Include abnormal ideas (delusions), abnormal perceptions (hallucinations, mainly auditory) and formal thought disorders such as disorganised thought and thought derailment
What are the negative symptoms of schizophrenia?
Thoughts, feelings and behaviours which should normally be present but which are diminished or absent in these individuals
Characterised by volitional, motor and behavioural deficits e.g. catatonia, abnormal posture, avolition and mutism
What are the cognitive symptoms of schizophrenia?
These include emotional disorders such as affective flattening, emotional withdrawal and anhedonia
Affective flattening commonly involves either no emotional response at all or inappropriate responses e.g. laughing at sad news
Why must schizophrenia be diagnosed and treated cautiously?
Any medical care heavily relies on a trusting interaction between practitioner and patient
Schizophrenia is mainly dealt with through talking with a patient, to try to identify their “reality” and how it differs from absolute reality
However patients are very firmly convinced of their reality and you will lose their confidence if they feel you don’t believe them (“trying to suppress the truth”, “working for the CIA”)
What is a key problem with the talking methods commonly used with schizophrenia?
Subjective method
In order to study and understand the condition, and develop appropriate treatments, we need objective measures that can be generalised between humans and animals, transferable and clearly measurable
How can studying the effect of brain injury on behaviour prove helpful in biological psychology?
For example, if we know someone has temporal lobe damage and we see symptoms resembling positive symptoms of schizophrenia, it suggests to us that the temporal lobe is involved in causing those symptoms in that condition
Similarly, finding frontal lobe involvement in presentations resembling negative symptoms of schizophrenia
What is the action of amphetamines and how can this help us in a study of schizophrenia?
Increases dopamine –> causes hallucinations and delusions
Thus suggests an involvement of dopamine in positive schizophrenic symptoms
What does LSD do and how does this help us to understand schizophrenia?
Mimics activity of serotonin –> hallucinations
Suggests involvement of serotonin in positive symptoms
What is Phencyclidine?
Antagonist of glutamate receptors –> cognitive, positive and negative-type symptoms (Ketamine also has similar effects)
Suggests possibility that glutamate may be involved in the core deficit underlying the problem of schizophrenia
What does the current therapeutic treatment of schizophrenia rely on?
Classical/typical antipsychotics (antagonists at dopamine receptors)
Newer/atypical antipsychotics (antagonists at dopamine and serotonin receptors)
The fact that these drugs have a therapeutic effect confirms the involvement of over-activity of dopamine and serotonin in causing schizophrenia or at least its symptoms
Why is targeting the core deficit (glutamate) currently tricky?
The glutamate system is very difficult to manipulate and even harder to localise - it is the most widespread neurotransmitter system in the brain, involved in a variety of functions which are in no way implicated in schizophrenia
Thus manipulation would have to be tightly targeted and specific to avoid undesirable side effects such as stroke-like or epileptic symptoms
What are 2 types of tasks which prove useful in understanding specificity of function of certain brain areas?
1) Latent inhibition (learning to ignore irrelevant stimuli - tests selective attention which requires temporal lobe function; positively symptomatic patients are deficient in these tasks, thus suggesting temporal lobe involvement in the condition
2) Wisconsin card sort/Tower of Hanoi - executive function relying on frontal lobe; negatively symptomatic patients perform poorly (first degree relatives of these patients are interestingly also deficient in these tasks)
