the biochemical explanation

what does an agonist do

a chemical that binds to a receptor of a cell and triggers that response by that cell, increases or regulates a neurotransmitter

what does an antagonist do

blocks or reduces the effect of a neurotransmitter

what are typical antipsychotics

antagonists of dopamine, can be effective in reducing positive symptoms 

how do typical antipsychotics work

by blocking dopamine receptors on the postsynaptic cell without activating them, meaning that dopamine cannot bind to the receptor. this reduces the signalling between synapses that communicate using this specific neurotransmitter

how do atypical antipsychotics work

serotonin is an inhibitory neurotransmitter which decreases the likelihood of the postsynaptic neuron firing an action potential

what do atypical antispsychotics do

block both dopamine and serotonin receptors, which helps to balance the amount of dopamine rather than reducing it as significantly as typical antipsychotics

what are some examples of atypical antipsychotics

clozapine and risperidone

what are some examples of typical antipsychotics

chlorpromazine and haloperidol

name 3 features of clozapine

they have a range of side effects although less than typical antipsychotics. non-compliance can result from side effects. their negative symptoms may involve memory loss, meaning they’d forget to take it or have voices telling them not to take them

summary of zhao et al (2016)

completed a meta-analysis of over 10,000 people taking 18 different antipsychotics in 56 randomised trials. 17 drugs were found to have a lower relapse rate rather than the placebos however 4 drugs had no greater effect than their placebos at reducing hospital admissions

strengths of zhao et al (2016)

large scale study, nomothetic approach, generalisations from large sample sizes- use of quantiative data. use of PANSS scale which has high validity. self reported data and observations by clinicians and caregivers were also provided.

weaknesses of the biochemical treatments

too idiographic, high rate of relapse- 30-70%. ineffective for all individuals- 30-80%. lots of side effects 

strength of the biochemical treatments

high validity of research, significant evidence it is more effective than placebos