User:Ahagman/sandbox

Environmental enrichment is a process concerning the stimulation of the brain by one's physical and social surroundings. Brains in richer, more stimulating environments have higher rates of synaptogenesis and more complex dendrite arbors, leading to increased positive brain activity. This effect takes place primarily during neurodevelopment, but also during adulthood in a lesser capacity. With extra synapses there is also increased synapse activity, leading to an increased size and number of glial energy-support cells. Environmental enrichment also enhances capillary vasculation, providing the neurons and glial cells with extra energy. The neuropil (neurons, glial cells, capillaries, combined together) expands, thickening the cortex. Research on rodent brains suggests that environmental enrichment may also lead to an increased rate of neurogenesis.

Research on animals finds that environmental enrichment could aid the treatment and recovery of numerous brain-related dysfunctions, including Alzheimer's disease and those connected to aging, whereas a lack of stimulation might impair cognitive development. Moreover, this research also suggests that environmental enrichment leads to a greater level of cognitive reserve, the brain's resilience to the effects of conditions such as aging and dementia.

Research on humans suggests that lack of stimulation, such as deprivation, delays and impairs cognitive development. Research also finds that attaining and engaging in higher levels of education, environments in which people participate in more challenging cognitively stimulating activities, results greater cognitive reserve.

Rehabilitation and resilience
Research in animals suggests that environmental enrichment aids in recovery from a diverse array of neurological disorders and cognitive impairments. There are two mains areas of focus: neurological rehabilitation and cognitive reserve, the brain's resistance to the effects of exposure to physical, natural, and social threats. Although most of these experiments used animal subjects, mainly rodents, researchers have pointed to the affected areas of animal brains to which human brains are most similar and used their findings as evidence to show that humans would have comparable reactions to enriched environments. The tests done on animals are thus meant to represent human simulations for the following list of conditions.

Neurological Rehabilitation
Autism

A study conducted in 2011 led to the conclusion that environmental enrichment vastly improves the cognitive ability of children suffering from autism. The study found that autistic children who receive olfactory and tactile stimulation along with exercises that stimulated other paried sensory modalities clinically improved by 42 percent while autistic children not receiving this treatment clinically improved by just 7 percent. The same study also showed that there was significant clinical improvement in autistic children exposed to enriched sensorimotor environments, and a vast majority of parents reported that their child's quality of life was much better with the treatment.

Alzheimer's disease

Researchers through environmental enrichment were able to enhance and partially repair memory deficits in mice between ages of 2 to 7 months with characteristics of Alzheimer's disease. Mice in enriched environments performed significantly better on object recognition tests and the Morris Water Maze than they had when they were in standard environments. It was thus concluded that environmental enrichment enhances visual and learning memory for those with Alzheimer's.

Huntington's disease

Research has indicated that environmental enrichment can help relieve motor and psychiatric deficits caused by Huntington's disease. It also improves lost protein levels for those with the disease, and prevents striatal and hippocampal deficits in the BDNF, located in the hippocampus. These findings have led researchers to suggest that environmental enrichment has a potential to be a possible form of therapy for those with Huntington's.

Parkinson's disease

Multiple studies have reported that environmental enrichment for adult mice helps relieve neuronal death, which is particularly beneficial to those with Parkinson’s disease. A more recent study shows that environmental enrichment particularly affects the nigrostriatal pathway, which is important for managing dopamine and acetylcholine levels, critical for motor deficits. Moreover, it was found that environmental enrichment has beneficial effects for the social implications of Parkinson’s disease.

Stroke

Research done in animals has shown that subjects recovering in an enriched environment 15 days after having a stroke had significantly improved neurobehavioral function. In addition these same subjects showed greater capability of learning and larger infarct post-intervention than those who were not in an enriched environment. It was thus concluded that environmental enrichment had a considerable beneficial effect on the learning and sensorimotor functions on animals post-stroke, aspects of the brain’s functions that are relevant to understanding humans. An April 2013 study also found that environmental enrichment socially benefits patients recovering from stroke. Researchers in that study concluded that stroke patients in enriched environments in assisted-care facilities are much more likely to be engaging with other patients during normal social hours instead of being alone or sleeping.

Rett syndrome

A 2008 study found that environmental enrichment was significant in aiding recovery of motor coordination and some recovery of BDNF levels in female mice with conditions similar to those of Rett syndrome. Over the course of 30 weeks female mice in enriched environments showed superior ability in motor coordination to those in standard conditions. Although they were unable to have full motor capability, they were able to prevent a more severe motor deficit by living in an enriched environment. These results combined with increased levels of BDNF in the cerebellum led researchers to conclude that an enriched environment that stimulates areas of the motor cortex and areas of the cerebellum having to do with motor learning is beneficial in aiding mice with Rett syndrome.

Amblyopia

A recent study found that adult rats with amblyopia improved visual acuity two weeks after being placed into an enriched environment. The same study showed that another two weeks after ending environmental enrichment, the rats retained their visual acuity improvement. Conversely, rats in a standard environment showed no improvement in visual acuity. It was thus concluded that environmental enrichment reduces GABA inhibition and increases BDNF expression in the visual cortex. As a result, the growth and development of neurons and synapses in the visual cortex were much improved due to the enriched environment.

Cognitive Reserve
Aging

Decreased hippocampal neurogenesis is a characteristic of aging. Environmental enrichment increases neurogenesis in aged rodents by potentiating neuronal differentiation and new cell survival. As a result, subjects exposed to environmental enrichment aged better due to superior ability in retaining their levels of spatial and learning memory.

Chronic spinal cord injuries

Research has indicated that animals suffering from spinal cord injuries showed significant improvement in motor capabilities even with a long delay in treatment after the injury when exposed to environmental enrichment. Social interactions, exercise, and novelty all play major roles in aiding the recovery of an injured subject. This has led to some suggestions that the spinal cord has a continued plasticity and all efforts must be made for enriched environments to stimulate this plasticity in order to aid recovery.

Prenatal and perinatal cocaine exposure

Research has shown that mice exposed to environmental enrichment are less affected by the consequences of cocaine exposure in comparison with those in standard environments. Although the levels of dopamine in the brains of both sets of mice were relatively similar, when both subjects were exposed to the cocaine injection, mice in enriched environment were significantly less responsive than those in standard environments. It was thus concluded that both the activating and rewarding effects are suppressed by environmental enrichment and early exposure to environmental enrichment can help prevent drug addiction.

Lead poisoning

During development, gestation is one of the most critical periods for exposure to any lead. Exposure to high levels of lead at this time can lead to inferior spatial learning performance. Studies have shown that environmental enrichment can overturn damage to the hippocampus induced by lead exposure. Learning and spatial memory that are dependent on the long-term potentiation of the hippocampus are vastly improve as subjects in an enriched environments had lower levels of lead concentration in their hippocampi. The findings also showed that enriched environments result in some natural protection of lead-induced brain deficits.

Maternal deprivation stress

Abandonment by a nurturing parent at a young age can result in maternal separation. This can lead to hindrance to emotional and intellectual behavior. Researchers suggest that environmental enrichment for those with maternal separation can reverse stress resulting from early-life adversity, particularly affecting the hippocampus and the prefrontal cortex. As these parts of the brain are main components of fear-response behavior, these findings have led researchers to conclude that environmental enrichment can significantly improve fear-response behavior in those who have suffered through early-life adversity.

Child neglect

In all children, maternal care is one of the significant influences for hippocampal development, providing the foundation for stable and individualized learning and memory. However, this is not the case for those who have experienced child neglect. Researchers determined that through environmental enrichment, a neglected child can partially receive the same hippocampal development and stability, albeit not at the same level as that of the presence of a parent or guardian. The results were comparable to those of child intervention programs, rendering environmental enrichment a useful method for dealing with child neglect.

Sensory deprivation

Studies have shown that with the help of environmental enrichment the effects of sensory deprivation can be corrected. For example, a visual impairment know as "dark-rearing" in the visual cortex can be prevented and rehabilitated. In general, an enriched environment will improve, if not repair, the sensory systems animals posses.