Abstract: The present invention provides a method to determine the extent of neuronal degradation due to aging, a learning disability, or a neurological disorder, which includes: (a) stimulating a neuronal cell population under suitable conditions so as to induce a late-phase long term potentiation; (b) stimulating a normal neuronal cell population under suitable conditions so as to induce a late-phase long term potentiation; and (c) comparing the duration of the late-phase long term potentiation of the neuronal cell population in step (a) with that of the normal neuronal cell population of step (b) so as to determine the extent of neuronal degradation due to aging, the learning disability or the neurological disorder. The learning disability or neurological disorder may be Alzheimer's Disease, a degenerative disorder associated with learning, memory or cognitive dysfunction, cerebral senility, multi-infarct dementia and senile dementia, electric shock induced amnesia or amnesia.