Objective: Assessment of cognitive functions in schizophrenia patients is very important. Because the cognitive deficiencies in memory and intelligence are the fundamental and underlying aspects. Both indicate from a structural and neurological similar deficits. The present study sought to examine the impact of severity and prognosis of schizophrenia on cognitive function, such as memory and intelligence and the relationship between intelligence and memory.

Material & Methods: In this study, 60 schizophrenia patients participate, who had at least 2 years of their diagnosis. Based on interviews by the PANSS scale in the two groups of 30 persons including the first group with mild symptoms (stable group) and the second group with severe symptoms (deteriorate group), were studied. Two groups by age, literacy, lack of mental retardation before diagnosis of disease, the use of ECT, the lack of anti-psychotic drug treatment more than three months during the past year were cloning. the Wechsler memory test and the raven IQ test for adults were used, the results were analyzed with using independent t-test, correlation and regression.

Results: Average of memory quotient in stable group with 77.4 and in deteriorated group with 65.93 had significant difference (P=0.002). Average of IQ in stable group with 84.26 and in deteriorated group with 76.9 had significant difference (P=0.015). Regression test showed that the memory can be predicted from IQ (P=0.001).

Conclusion: with severity of disease and deteriorated of schizophrenia and negative symptoms, deficiency in memory, has increased. In these patients, there was a positive relationship between intelligence and memory. The level of intelligence was in deteriorated group significantly lower than from stable group