Hippocampus increases volume in
response to exercise in patients with schizophrenia
Potentially beneficial increases in the volume of the
hippocampus occur in response to exercise both in patients with schizophrenia
and healthy controls, according to a report in the February issue of Archives
of General Psychiatry, one of the JAMA/Archives journals. The findings suggest
that the brain retains some plasticity, or ability to adapt, even in those with
psychotic disorders.
Schizophrenia is known to be associated with a reduced
volume in the area of the brain known as the hippocampus, which helps regulate
emotion and memory, according to background information in the article. "In contrast
to other illnesses that may display psychotic features, such as bipolar disorder,
schizophrenia is often characterized by incomplete recovery of psychotic symptoms
and persistent disability," the authors write. "These clinical features of illness
may relate to an impairment of neural plasticity or mechanisms of reorganizing
brain function in response to a challenge."
The formation of new neurons is one component of plasticity;
previous studies have shown that neuron growth in the hippocampus of healthy individuals
can be stimulated by exercise. Frank-Gerald Pajonk, M.D., of The Saarland University
Hospital, Homburg, and Dr. K. Fontheim's Hospital for Mental Health, Liebenburg,
Germany, and colleagues assessed changes in hippocampal volume in response to
an exercise program in both male patients with schizophrenia and men who had similar
demographics and physical characteristics but did not have the condition.
Eight participants with schizophrenia and eight controls
were randomly assigned to exercise (supervised cycling) three times per week for
30 minutes, whereas an additional eight patients with schizophrenia instead played
tabletop football for the same period of time. The game enhances coordination
and concentration but does not affect aerobic fitness. All participants underwent
fitness testing, magnetic resonance imaging of the hippocampus, neuropsychological
testing and other clinical measures before and after participating in the program
for 12 weeks.
Following exercise training, hippocampal volume increased
12 percent in patients with schizophrenia and 16 percent in healthy controls.
"To provide a context, the magnitude of these changes in volume was similar to
that observed for other subcortical structures when patients were switched from
typical to atypical antipsychotic drug therapy," the authors write. Conversely,
patients with schizophrenia who played tabletop football instead of exercising
experienced a 1 percent decrease in hippocampal volume.
Aerobic fitness also increased among all who exercised,
and improvement in test scores for short-term memory was correlated with increases
in hippocampal volume among patients and healthy controls.
"Further clinical studies are needed to determine if
an incremental improvement in the disability related to schizophrenia could be
obtained by incorporating exercise into treatment planning and lifestyle choice
for individuals with the illness," the authors conclude.
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