Mild cognitive impairment (MCI) is generally referred to as the transitional zone between normal cognitive aging and early dementia or clinically probable Alzheimer’s disease (AD) (1), although not all AD patients pass through an MCI stage. The term was first coined by Petersen (2). Most individuals with MCI eventually develop AD, which suggests MCI may be the earliest phase of the AD (3–6). MCI can be divided into two broad subtypes: amnestic (memory-affecting) MCI or non-amnestic MCI (2,7). Other functions, such as language, attention, and visuospatial skills, may be impaired in either type. Amnestic mild MCI patients characteristically have subtle but measurable memory disorder not associated with dementia. Individuals with MCI are at an increased risk of developing AD, or another form of dementia with a rate of progression between 10% and 15% per year (8,9), although there have been cases where patients have reverted to normal (1,10,11). Criteria for MCI include (a) a memory complaint corroborated by an informant; (b) objective memory test impairment (age and education adjusted); (c) general normal global intellectual function; (d) activities of daily living not disturbed; (e) clinical dementia rating (CDR) score of 0.0 to 0.5; (f) no dementia; and (g) a clinical evaluation that revealed no other cause for memory decline (12). Moreover, neuroim-aging studies by magnetic resonance imaging (MRI) demonstrate the atrophy of the hippocampus or entorhinal cortex in MCI patients, indicating the relationships with transition of normal aging to MCI, then later to clinical AD (13). Pathologically, MCI brain shows mild degradation of the hippocampus, entorhinal cortex, sulci, and gyri using MRI (14,15). These aforementioned areas undergo considerable degradation in AD (16–20). Since the hippocampus is the region of the brain primarily responsible for processing memory, it is clearly understandable why those persons with AD and MCI have memory loss.