Although we did not cover all of the behavioral assessments in the rodent stroke model, we did cover many that are commonly performed. The chosen battery of functional assessments should be able to detect even mild impairments. Because there are critical periods that are best for detecting deficits, identifying assessment and rehabilitation times is essential. For the best chance of ensuring wide orbit radio automation manual successful functional evaluation after stroke in a rodent model, it is important to obtain baseline data before experimental manipulations. In addition, for tasks that require pre-training, animals must be properly trained before surgery for dependable post-operative data. Furthermore, reducing the animal’s stress and anxiety during testing is imperative to obtain reliable data .

The use of enriched environments early in development is believed to be particularly effective during critical or sensitive periods, when brain plasticity is especially influenced by experience. The commercial industry and some political entities have propagated the idea that accelerating the progression of sensitive periods through early training is beneficial for children. Although animal studies have shown that the length of sensitive periods depends on experience, there is no evidence showing that shortening such periods is advantageous. However, many subsequent replications of this study did not support the original findings, and they have since been largely discredited (Pietschnig et al., 2010).

We had previously shown that if adult rats are given amphetamine, cocaine, or nicotine and then later placed in complex environments, neuronal plasticity was blocked (Hamilton & Kolb, 2005; Kolb, Gorny, Samaha, & Robinson, 2003b). In a subsequent study we gave juvenile rats methylphenidate and then in adulthood we placed these animals in complex environments and, once again, we found that the early drug exposure blocked the expected experience-dependent changes in the cortex (Comeau & Kolb, 2011). Furthermore, in a parallel study we showed that juvenile methylphenidate exposure impaired performance on neuropsychological tasks sensitive to prefrontal functioning. It has long been known that early exposure to alcohol is deleterious for brain development, but it has only recently been shown that other psychoactive drugs, including prescription drugs, can dramatically alter brain development.

Although many were impressed to learn that the cerebral cortex could increase its thickness in response to enriched living conditions, they raised the question about whether enrichment might similarly affect older animals. Once middle-aged rats brains showed positive responses to enrichment, the next step was to experiment with very old animals. The study results suggest that rats housed in standard conditions exhibit a higher demand for interactions with the new environment. However, once novelty is introduced, rats from the enriched environments spend more time than their standard counterparts exploring the new objects. No significant differences have been observed in the behaviour of rats from the stable and changeable conditions.

Interestingly, an enhanced environmental stimulation is able to restore ocular dominance plasticity not only in young adults , but also in the aging visual cortex, though to a slightly lower extent . Plasticity in response to one week of MD is detectable at both the level of subthreshold modifications of postsynaptic potentials and that of spike properties of cortical neurons (by means of single-unit recordings). This effect on neural plasticity offers an attractive explanation for the well known positive effects elicited by EE in the aging brain (e.g. . Accordingly, intervention protocols aimed at promoting an active lifestyle in aging people should be encouraged. Enrichment of the environment has long been proposed as a treatment or strategy for increasing cognitive ability and well-being, namely in rodents (Cooper and Zubek, 1958; Manosevitz, 1970) and in children in educational contexts (Stoddard and Wellman, 1940; Gruber, 1975). In animal studies, the nature of enrichment varies , but typically involve access to larger, more stimulating environments, with increased opportunities for socialization and voluntary physical activity (van Praag et al., 2000). “Enrichment” generally refers to increases in the variety and/or amount of multisensory stimulation, with the goal being to elicit exploratory behavior (Baroncelli et al., 2010).