is conventionally divided into relay and diffuse projections nuclei. The relay nuclei project to sensory and motor cortical regions and receive projections from the same cortical areas. These recurrent connections may allow the thalamus to modulate sensory and motor input. The diffuse projection nuclei are believed to be part of a system that governs the level of arousal in the brain. Whatever its roles, the thalamus must have a fundamental and important function in human cognition because of its extensive connections to the rest of the brain(Joseph, 1999). Research on thalamic abnormalities in schizophrenia patients has shown a significant decrease in size, but it is not reported due to the fact that the findings could be due to partial voluming with the enlarged ventricles. However, their has been reports of abnormal activation in the thalamus when schizophrenic patients are experiencing auditory hallucinations. The final area of the brain that has been research in schizophrenic patients is the cerebellum. The cerebellum is phylogenetically interesting, which suggests that it could perform cognitive as well as a motor functions in humans. This makes this particular area well suited to perform massive parallel processing because of the nature of its cellular array. Output from the cerebellum passes through the thalamus before projecting on to various neocortical regions, including the prefrontal cortex. The entire system appears to be a reciprocally connected circuit with modular specificity. Cerebro-cerebellar connections have been established for motor, sensory, and limbic regions, as well as for parts of prefrontal and parietal association cornices (Andreasen et al., 1998). Schizophrenic patients with abnormalities in this area of the brain, suffer from verbal associative learning, and visual spatial skills, agrammatic speech, impaired memory, impaired procedural learning, decreased general intelligence as measured by IQ...
