Effect of environmental enrichment on neuroplasticity

Environmental enrichment can be defined as external stimulation by the physical or social surroundings. Classical and rapid-acting antidepressants have been shown to bind directly to BDNF receptor TrkB to promote neuronal plasticity. Like antidepressants, environmental enrichment has been shown to promote neuronal plasticity in the brain, although the exact mechanisms of action are unknown. Environmental enrichment could thus potentially act as a complementary or alternative non-pharmacological treatment for neuropsychogical disorders. This study investigated the effect of 10 weeks of environmental enrichment on neuroplasticity-dependent behaviour in female wildtype, BDNF-het, and hTrkB-Y433F mutant mice. Mice were randomly assigned into standard or enriched housing. The enriched cages measured 90x90x30cm and enrichment consisted of a large social group (10-12 mice), various tunnels and tubes, running wheels, extra igloos, extra bedding material, and wooden blocks. The standard housing groups were in standard IVC cages in groups of 3- 4 with access to standard enrichment: one igloo, bedding material, handling tube, and wooden blocks. Behavioural tests, OF, EPM, and NOR, were conducted to assess memory, learning, and anxiety-like behaviour. Environmental enrichment was seen to differentially affect the behavioural test outcomes for the different genotype groups. The next steps will be to assess if there are differences at a molecular level. More research is needed to determine the exact mechanisms of action behind environmental enrichment. Environmental enrichment seems to be a promising avenue for alternative and complementary treatment of brain disorders.