Diseases that cause neurodegeneration, such as Alzheimer's disease, can also be a factor in a person's short-term and eventually long-term memory. Short term memory performance is majorly influenced by the nature of diet that one takes. More intake of blue berries has shown to improve short term memory after continuous use whereas alcohol decreases short term memory performance. Damage to certain sections of the brain due to this disease causes a shrinkage in the cerebral cortex which disables the ability to think and recall memories.