New Form of Brain Plasticity: How Social Isolation Disrupts Myelin Production
ScienceDaily (Nov. 11, 2012) — Animals that are socially isolated for prolonged periods make less myelin in the region of the brain responsible for complex emotional and cognitive behavior, researchers at the University at Buffalo and Mt. Sinai School of Medicine report in
Nature Neuroscience online.
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This paper reveals that the stress of social isolation disrupts the sequence in which the myelin-making cells, the oligodendrocytes, are formed.
In the experiment, adult mice, normally social animals, were isolated for eight weeks to induce a depressive-like state. They were then introduced to a "novel" mouse, one they hadn't seen before; while mice are normally highly motivated to be social, those who had been socially isolated did not show any interest in interacting with the new mouse, a model of social avoidance and withdrawal.
Brain tissue analysis of the socially isolated animals revealed significantly lower than normal levels of gene transcription for oligodendrocyte cells in the prefrontal cortex, a brain region responsible for emotional and cognitive behavior.