cognitive: hemsley 1993- neuropsychological theory
Packages of informaion stored in our memories as schemas influence the way we interpret later events. Schizophrenics are subjected to sensory overload which means that superficial incidents might be seen as higly relevant. internal thoughts are sometimes not recognised as arising from memory and so are attributed to an external source and experienced as auditory hallucinations.
+useful in explaining some symptoms such as delusions and hallucinations.
-although Hemsley has linked this model to an underlying eurological system , there is little emperical evidence to support his theory.
-reductionist as it ignores other influential factors such as enironment, that might trigger the onset and maintanance of schizophrenia.
cognitive: frith 1992-cognitive process
Most symptoms of schizophrenia can be explained in terms of deficits in three processes called the meta-representations which are part of a general mechanism. these are: inability to generate willed action, inability to monitor willed action and inability to monitor the beliefs and intentions of others. Faulty operations of this mechanism is due to a functional disconnection between frontal areas of the brain that control perception. He detected changes in celebral blood flow in the brains of people with schizophrenia when engaged in specific cognitive tasks.
+replicable method, therefore has high reliability.
-inconclusive research support and theory is regarded as speculative (theoretical).
-also reductionist as it fails to take into account environmental factors.