Negative symptoms: which represent a loss or a decrease in the ability to initiate plans, speak, express emotion, or find pleasure in everyday life. These symptoms are harder to recognise as part of the disorder and can be mistaken for laziness or depression
Cognitive symptoms (or cognitive deficits): which are problems with attention, certain types of memory, and the executive functions that allow us to plan and organise. Cognitive deficits can also be difficult to recognise as part of the disorder but are the most disabling in terms of leading a normal life" (NARSAD, 2006)
It has been reported that "psychiatric researchers at The Zucker Hillside Hospital campus of The Feinstein Institute for Medical Research, including NARSAD-supported and affiliated scientists, have uncovered evidence of a gene that appears to influence intelligence" (NARSAD, 2006). This discovery means that the genes that are associated with the cognitive impairment caused by schizophrenic sufferers, has been mapped to the "dysbindin-1 gene (DTNBP1)" (NARSAD, 2006). Dr. Katherine Burdick will be reporting in the May 15 print issue of Human Molecular Genetics, that "a robust body of evidence suggests that cognitive abilities, particularly intelligence, are significantly influenced by genetic factors. Existing data already suggests that dysbindin may influence cognition" (Burdick, 2006).
There is also evidence found by Lipska, Law, Weinberger, Kleinman, (2006) in ...