A Critical Period for Social Experience–Dependent Oligodendrocyte Maturation and Myelination

Abstract

A Critical Period for Glia The brain develops in fits and starts—while one system is completed, another system may still be under construction. Such transient states are known as critical periods, and during these specific aspects of brain development may become more sensitive to outside agents than they would be later. Makinodan et al. (p. 1357 ) observed the effect of environmental conditions on the brains of mice bioengineered to develop fluorescent oligodendrocytes. The mice were exposed to a variety of social conditions during rearing, ranging from isolation to a normal laboratory cage setting, or to settings enriched with extra buddies and a steady rotation of new play toys. The results show that social isolation leaves a developmental trace that persists into adulthood. Specifically, they found that oligodendrocytes, which produce the myelin that insulates neurons, were underdeveloped, suggesting that there may be a critical period that governs development of these glial oligodendrocyte cells.

Measuring the Plasticity of Social Approach: A Randomized Controlled Trial of the Effects of the PEERS Intervention on EEG Asymmetry in Adolescents with Autism Spectrum Disorders

“…These dramatic developments in neural structure and function may be affected by the social environment available at or before this developmental stage (Makinodan et al 2012;Sheridan et al 2012). A multitude of studies have established that social isolation and loneliness are a significant determinant of physical health and longevity (Cacioppo and Hawkley 2009;Holt-Lunstad et al 2010;Uchino et al 1996), and mental health in humans (see Hawkley and Cacioppo 2010;Heinrich and Gullone 2006, for reviews).…”

“…Individuals that perceive themselves as isolated and lonely show weaker prefrontal and ventral striatal reward system responses to pleasant pictures of people, less activation in perspective-taking areas of temporo-parietal cortex , and more maladaptive cardiovascular responses to threatening or negative stimuli (Ong et al 2012). Research has also shown that children who experience isolation early in development show significantly smaller gray matter and white matter volumes as adolescents (Mehta et al 2009), and that isolation in post-weaned animals reduces myelination of white matter tracts (Makinodan et al 2012) and reduces prefrontal cortical volume (Fone and Porkess 2008). Although these studies of isolation do not perfectly mirror the An additional factor to consider, when examining links between social experiences and neural patterns, is that individual differences in the relative dominance of one hemisphere over the other have been linked to certain psychological styles (Tomarken et al 1992).…”

Developmental pruning of early-stage myelin segments during CNS myelination in vivo

“…The membrane-bound neuregulin1 (NRG1) is an axonal ligand for glial ErbB receptors, and NRG1-ErbB signaling is required for myelination in both the peripheral and central nervous systems [5][6][7][8]. To examine whether this signaling pathway has a role in the early-stage myelin pruning, we first used two previously characterized morpholino oligomers (MOs) to knock down the expression of NRG1 in zebrafish larvae.…”

Prevención de la carencia afectiva crónica: nuevos paradigmas en el modelo de familia de acogida temporal

“…Las investigaciones en neurociencias y particularmente los estudios por neuro-imágenes demuestran que la mielinización y desarrollo de las neuronas dependen, desde el principio de la vida, de la calidad y cantidad de estímulos que el niño reciba en su interacción con su entorno. Este proceso se vería comprometido por la experiencia de aislamiento social y de carencia afectiva a muy temprana edad 27 . Esta condición traumática se encuentra asociada a un déficit en la mielinización que podría modificar la velocidad de conducción de los impulsos y dificultar un mejor procesamiento de la información, pudiendo además relacionarse con déficits en la memoria y en las interacciones sociales 28 .…”