Normal cells primarily produce energy with the help of the "mitochondria". These "small organs" are also called the "powerhouses of the cell" turn the sugars, fats and proteins that is eaten into forms of chemical energy that the body can use to carry on living. This process is called oxidative phosphorylation. In addition to the help from the mitochondria and oxidative phosphorylation, most cells can produce energy by lactic acid fermentation. This process is less energy efficient but faster and used by the brain, muscle or other organs under specific circumstances and energy demands, even in the presence of abundant oxygen. It is also called aerobic glycolysis. Aerobic glycolysis and oxidative phosphorylation are the two major mechanisms involved in brain energetics.

The consequences of Alzheimer's disease (AD) (deposition of amyloid plaques and neurofibrillary tangles) are known. The cause of these deposition of proteins is not. Some scientist argue that an increase in oxidative phosphorylation activity and a lack of ability to shift to aerobic glycolysis are the underlying source of these changes. The purpose of this study is to test whether there is a correlation between neuroenergetic levels of aerobic glycolysis/oxidative phosphorylation and risk for Alzheimer's disease. The study will examine these neuroenergetic adaptations in a group of 15 elderly participants (age range: 70-85 y/o) with amnestic mild cognitive impairment (aMCI) and 30 cognitively normal controls (NL). Multimodal (MR/PET) and multinuclear (31P/1H) neuroimaging will allow us to gain access to a uniquely comprehensive and highly consistent view of neuroenergetic adaptations in both the clinical and preclinical stages of Alzheimer's disease.

Inclusion Criteria:

• NL Group: Adults (male and female) aged >70 years in overall excellent health with normal cognition (CDR=0), and at least high school graduate level education.
• aMCI Group: Adults (male and female) aged >70 years, Clinical Dementia Rating (CDR)= 0.5 - 1 and Mini-Mental State Examination (MMSE): 20-25
• English as first language or demonstrated proficiency in English for non-native speakers

Exclusion Criteria:

• Any tumor, stroke, or trauma that would result in abnormal radiological findings History of bipolar disorder, schizophrenia, intellectual disability or substance abuse MRI scanner contraindications

Adults (male and female) aged >70 years in overall excellent health with normal cognition (CDR=0), and at least high school graduate level education.