Response of the brain to enrichment

Abstract

Before 1960, the brain was considered by scientists to be immutable, subject only to genetic control. In the early sixties, however, investigators were seriously speculating that environmental influences might be capable of altering brain structure. By 1964, two research laboratories proved that the morphology and chemistry or physiology of the brain could be experientially altered (Bennett et al. 1964, Hubel andWiesel 1965). Since then, the capacity of the brain to respond to environmental input, specifically "enrichment," has become an accepted fact among neuroscientists, educators and others. In fact, the demonstration that environmental enrichment can modify structural components of the rat brain at any age altered prevailing presumptions about the brain's plasticity , Diamond 1988. The cerebral cortex, the area associated with higher cognitive processing, is more receptive than other parts of the brain to environmental enrichment. The message is clear: Although the brain possesses a relatively constant macrostructural organization, the ever-changing cerebral cortex, with its complex microarchitecture of unknown potential, is powerfully shaped by experiences before birth, during youth and, in fact, throughout life. It is essential to note that enrichment effects on the brain have consequences on behavior. Parents, educators, policy makers, and individuals can all benefit from such knowledge.

Environmental enrichment increases progenitor cell survival in the dentate gyrus following lateral fluid percussion injury

“…In support of this hypothesis, EE improves spatial learning in intact animals [13,54,81] and increases neurogenesis in the dentate gyrus of the hippocampus [54,81]. Furthermore, antimitotic drugs that block cell proliferation, also block the beneficial effects of EE on hippocampal-dependent learning [7].…”

“…6), and 3 h/d of EE produced increases in neurogenesis and improvements in memory and learning in intact mice [18] and rats [7]. Even shorter durations, as little as 40 min/d, was sufficient to produce alterations in mRNA and brain weight in developing animals [13]. Thus, it appears that alterations to the brain can be produced with relatively short periods of EE, but whether this confers optimal benefits remains to be determined.…”

“…First, specific pathogen free (SPF) guidelines and space restrictions of our animal vivarium prevented us from housing animals in EE on a continuous basis. Second, whereas most previous studies have used continuous housing in an enriched environment, there have been a few reports demonstrating that short daily periods of EE, ranging from 45 min to 3 hours per day [13,18], could produce alterations in the brain. Third, shorter periods of EE may be more translatable to certain clinical situations than continuous EE.…”

“…Environmental enrichment (EE) is a well established intervention for attenuating cognitive deficits associated with FP injury [4,28,35,59,76], as well as other experimental brain injury models [13,79]. Although our understanding of how EE mediates functional recovery after brain injury is incomplete, one explanation is that it promotes adaptations of surviving neural networks, enabling them to take over functions of damaged regions of the brain.…”

Promoting positive states: the effect of early human handling on play and exploratory behaviour in pigs

“…In experiments carried out in rats, it was shown that rats reared in a rich environment with many exploratory objects developed a significantly thicker cerebral cortex than rats reared in a poor environment (Diamond, 2001; see also Levine, 2005). The increased thickness was due to a larger number of brain cells and more extensive branching of their dendrites and interconnections to other cells, which is associated with a better brain plasticity.…”