Neurological effects of moving from an enriched environment to social isolation in adult mice

[littlemissmartypants]

Neurological effects of moving from an enriched environment to social isolation in adult mice

Authors
*V. HENG1, M. J. ZIGMOND2, R. J. SMEYNE1;
1Neurosci., Thomas Jefferson Univ., Philadelphia, PA; 2Neurol., Univ. of Pittsburgh, Pittsburgh, PA

Abstract
As social animals, our health depends on interactions with others. Yet millions suffer from chronic social isolation (SI), including those living in nursing/assisted living facilities as well as their caregivers. SI also manifests in our criminal justice system, where more than 80,000 people are housed in solitary confinement (SC); defined as segregation from the general prison population for at least 22-23 hours/day for a period longer than 30 days. This condition is known to have toxic physiological and psychological consequences, including depression, stress, cognitive deficits, memory loss, and impaired concentration. Despite these well-known consequences, little is known about the impact of SI on the brain itself. In this study, we have developed a mouse model of SC where animals (C57Bl/6J) are born and raised in an enriched environment (EE) and then as adults (4 months of age) are placed into isolated conditions. After 30 days of isolation, we examined the shape, size, and arborization of neurons in specific regions of the brain selected because of their relevance to known psychological effects induced by SC including alterations in memory (hippocampus), loss of sensory threshold and discrimination (somatosensory cortex) and deficits in motor function (motor cortex). We used a modified Golgi-Cox method together with confocal microscopy and Neurolucida 360 image analysis to determine the total and average dendritic length per neuron, spine counts, the total neuronal volume, and the extent of dendritic branching. After 1 month of isolation significant differences were observed in the total neuronal volume, with the greatest effect in layer V of pyramidal neurons in the motor cortex. In addition, these changes were sex-dependent, with greater deficits in males. Despite these changes, we do not yet know whether these changes were dependent on the age at which isolation starts, the duration of isolation, are permanent, or alter behavior.

More at link.
https://abstractsonline.com/pp8/#!/4649/presentation/20940

♡ lmsp

[JHan]

1. I'd read studies about this on rates of cancer survival.

fascinating stuff.