curcumin functions to reduce inflammation and free radicals. Curcumin also increases BDNF post TBI, which will improve synaptic plasticity, cognition, and memory.
High saturated fat and sugar diet causes reduced BDNF in the hippocampus. This is an animal model. The effect was a reduction in spacial learning. Dietary choice can effect the neuroplasticity and learning capacity of the hippocampus.
DHA enriched diet plus exercis improved cognition through a increase in brain derived neurotrophic factor (BDNF). The result was increased neuroplasticity. Additionally, they were shown to reduce hippocampal lipid peroxidation.
Neurogenesis and neuroplasticity are under epigenetic control. Stress and aging downregulate adult neurogenesis; whereas physical activity, environment enrichment and learning/memory increase. Check out figure 1. Exercise increases BDNF and hence neuroplasticity. This was a synRas mouse study.
The absolute best way to promote neurogenesis is through exercise. This is through an increase in BDNF. There are ways to augment this: curcumin, n-3, nutrition... The concept that the brain doesn't heal is out the window.