There are considerable differences in the assessment of schizophrenic symptoms in the last 20 years. Formerly, the focus of assessments was observable symptoms like hallucinations and paranoid symptoms but recently neurodevelopmental and cognitive aspects of schizophrenia has become the focus of interest.

Schizophrenic patients have various cognitive dysfunctions. Dysfunctions in attention, memory and executive functions develop on the basis of a generalized cognitive dysfunction.

Typical antipsychotics have no effect on the cognitive dysfunctions of schizophrenia, on the contrary they worsen the cognitive dysfunctions. It is shown that atypical antipsychotics which have strong 5-HT2A antagonism improve cognitive dysfunctions in schizophrenia in comparative studies with typical antipsychotics.

In the present review, the neurobiological basis of the effects of atypical antipsychotics on cognitive dysfunctions in schizophrenia is discussed and the effects of serotonin and dopamin antagonistic atypical antipsychotics currently used in Turkey (clozapine, risperidone, olanzapine and quetiapine) on cognitive dysfunctions in schizophrenia are reviewed.