Saturday, May 30, 2009

Prefrontal Cortex

The prefrontal cortex is the anterior portion of the frontal lobes of the cerebrum. It lies in front of the motor and premotor areas. The prefrontal cortex is thought to be involved in planning complex cognitive behavior and in the expression of personality and appropriate social behavior. The prefrontal cortex can be divided into three basic areas: the orbitofrontal and ventromedial areas; the dorsolateral prefrontal cortex; the anterior and ventral cingulate cortex.

The prefrontal cortex has been shown to participate in the association of events separated by time and is responsible for the executive functions, which include mediating conflicting thoughts, making choices, and governing social control. When the pathways between the prefrontal cortex and the rest of the brain are damaged due to head injury, massive personality changes can result.

Many diseases, such as schizophrenia, bipolar disorder and ADHD, have been related to dysfunction of the prefrontal cortex, and thus this area of the brain offers the potential for new treatments of these diseases. Markers of inhibitory neurotransmission are altered in the prefrontal cortex (PFC) of subjects with schizophrenia, and several lines of evidence suggest that these alterations may be most prominent in the subset of GABA-containing neurons that express the calcium-binding protein, parvalbumin (PV).

The prefrontal cortex responds mostly to stimuli signaling the need for movement; nevertheless it is also responsible for many other specialized functions. It gets information from all sensory systems and can integrate a large amount of information. It has been shown that the prefrontal cortex is responsible for working memory. Working memory is defined as the information that is currently available in memory for working on a problem.