Cingulate gyrus

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Clinic

  • Cingulate cortex is a part of the brain situated in the medial aspect of the cerebral cortex.
  • It is usually considered part of the limbic lobe.
  • It receives inputs from the thalamus and the neocortex, and projects to the entorhinal cortex via the cingulum.
  • It is involved with emotion formation and processing, learning, and memory.
  • The combination of these three functions makes the cingulate gyrus highly influential in linking motivational outcomes to behavior (e.g. a certain action induced a positive emotional response, which results in learning).
  • This role makes the cingulate cortex highly important in disorders such as depression and schizophrenia.
  • It also plays a role in executive function and respiratory control.


Clinical significance in schizophrenia

Using a three-dimensional magnetic resonance imaging procedure to measure the volume of the rostral anterior cingulate gyrus (perigenual cingulate gyrus), Takahashi et al. (2003) found that the rostral anterior cingulate gyrus is larger in control (healthy) females than males, but this sex difference was not found in people with schizophrenia. People with schizophrenia also had a smaller volume of perigenual cingulate gyrus than control subjects.

Haznedar et al. (2004) studied metabolic rate of glucose in anterior and posterior cingulate gyrus in people with schizophrenia, schizotypal personality disorder (SPD) and compared them with a control group. The metabolic rate of glucose was found to be lower in the left anterior cingulate gyrus and the right posterior cingulate gyrus in people with schizophrenia relative to controls. Although people with SPD were expected to show a glucose metabolic rate somewhere between the individual with schizophrenia and controls, they actually had higher metabolic glucose rate in the left posterior cingulate gyrus. The volume of the left anterior cingulate gyrus was reduced in people with schizophrenia as compared with controls, but there was not any difference between people with SPD and people with schizophrenia. From these results it appears that the schizophrenia and SPD are two different disorders.

A study of the volume of the gray and white matter in the anterior cingulate gyrus in people with schizophrenia and their healthy first and second degree relatives revealed no significant difference in the volume of the white matter in the people with schizophrenia and their healthy relatives. Nonetheless a significant difference in the volume of gray matter was detected, people with schizophrenia had smaller volume of gray matter than their second degree relatives, but not relative to their first degree relatives. Both the person with schizophrenia and their first degree healthy relatives have smaller gray matter volume than the second degree healthy relatives. It appears that genes are responsible for the decreased volume of gray matter in people with schizophrenia.

Fujiwara et al. (2007) did an experiment in which they correlated the size of anterior cingulate gyrus in people with schizophrenia with their functioning on social cognition, psychopathology and emotions with control group. The smaller the size of anterior cingulate gyrus, the lower was the level of social functioning and the higher was the psychopathology in the people with schizophrenia. The anterior cingulate gyrus was found to be bilaterally smaller in people with schizophrenia as compared with control group. No difference in IQ tests and basic visuoperceptual ability with facial stimuli was found between people with schizophrenia and the control.

Summary

People with schizophrenia have differences in the anterior cingulate gyrus when compared with controls. The anterior cingulate gyrus was found to be smaller in people with schizophrenia. The volume of the gray matter in the anterior cingulate gyrus was found to be lower in people with schizophrenia. Healthy females have larger rostral anterior cingulate gyrus than males, this sex difference in size is absent in people with schizophrenia. The metabolic rate of glucose was lower in the left anterior cingulate gyrus and in the right posterior cingulate gyrus.

In addition to changes in the cingulate cortex more brain structures show changes in people with schizophrenia as compared to controls. The hippocampus in people with schizophrenia was found to be smaller in size when compared with controls of the same age group, and, similarly, the caudate and putamen were found to be smaller in volume in a longitudinal study of people with schizophrenia. While the volume of gray matter is smaller, the size of the lateral and third ventricles is larger in people with schizophrenia.