The proteins responsible for regulating the processes of cell birth and cell death in the brain are known as neurotrophic factors, one of which is BDNF. When a neuron obtains an adequate amount of these proteins during development, it survives, while neurons that do not receive enough die. As these proteins are not abundant, neurons must compete for them during development and even into old age.
Consequently, decreased levels of BDNF have been associated with neurodegenerative disorders such as Parkinson’s disease, Alzheimer’s disease, multiple sclerosis, and Huntington’s disease. Higher levels are associated with improved cognitive functioning, mental health, and memory.