Dopamine is widely believed to be involved in schizophrenia because its featured in the functioning of brain systems related to the symptoms of schizophrenia
original dopamine hypothesis
highdopamine activity in the subcortex (central areas of the brain) associated with hallucinations and poverty of speech
may explain specific symptoms e.g speech poverty
updates dopamine hypothesis
has added low levels of dopamine in the prefrontal cortex, could explain negative symptoms
explains origins of abnormaldopamine - genetic variations and early experiences of stress make some people more sensitive to corticalhypodopaminergia and hence hyperdopaminergia (howes)
one strength is support for dopamine in the symptoms of schizophrenia
Amphetamines (increase dopamine) mimicsymptoms (curran 2004). antipsychotic drugs (reduce dopamine) reduceintensity of symptoms (tauscher 2014). candidate genes act in the production of dopamine or dopaminereceptors. this strongly suggests that dopamine is involved in the development of schizophrenia
one limitation is evidence for a central role for glutamate
postmortem and scanningstudies found raised glutamate in people with schizophrenia (McCutcheon 2020). also, several candidategenes for schizophrenia are believed to be involved in glutamateproduction or processing. this means that a strongcase can be made for a role for other neurotransmitters in schizophrenia