amnestic mild cognitive impairment

Amnestic mild cognitive impairment (MCI) is a transitional stage between normal aging and Alzheimer disease, characterized by noticeable memory dysfunction while other cognitive abilities remain intact. This condition is a type of memory disorder that can result from various factors, including diffuse brain diseases and specific structural damage within the brain.12

The pathology of amnestic MCI is closely linked to the underlying processes of Alzheimer disease. Key neuropathological features include the presence of neuritic plaques and neurofibrillary tangles in the brain. Neuritic plaques are formed by deteriorating neuronal material surrounding deposits of amyloid beta protein, while neurofibrillary tangles are twisted protein fibers within nerve cells composed of tau protein. These abnormalities are thought to interfere with normal cellular function, though whether they cause or are a consequence of the disease is still under investigation. Deficiencies in neurotransmitters like acetylcholine, which plays a role in memory, are also observed.1

While the exact causes are complex, research suggests that abnormal insulin signaling in the brain and genetic variants, such as those in the APP and APOE genes, may contribute to the development of Alzheimer disease and related cognitive impairments. Memory loss, particularly for recent events, is a common symptom, and in some cases, it can be a precursor to more severe dementia.12