Extensive research in the nervous system has supported the idea that epigenetic chromatin structure regulation plays a crucial role in development, cellular differentiation, behavior, and memory formation. Alzheimer's disease (AD) is a degenerative brain disorder that results in a progressive decline in one's cognition, memory, and learning. Parkinson's disease is a movement disorder condition that is characterized by tremors, muscle rigidity, bradykinesia, and postural instability. Early life experiences have a strong, lasting effect on stress- and anxiety-mediated behavioral responses in an organism. Alterations in covalent modifications of histones and associated DNA modulate gene expression, to yield altered gene expression patterns, which may ultimately contribute to the phenotypic manifestation of neurological disorders. Although still in its elementary stages, further investigation of chromatin-modifying drugs as a therapeutic approach for neuropsychiatric, eurodevelopmental, and neurological disorders may produce positive results.