The Nicotinic Cholinergic System and Cognitive Aging

CHRMS 16-284

Prior research has shown that a chemical system in the brain called the cholinergic system is primarily responsible for cognitive symptoms seen in people with dementia. While therapeutic benefits are clear in dementia, what remains uncertain is the role that the cholinergic system in general and a subset of receptors called the nicotinic system plays in cognition in healthy non-demented older adults (referred to as normal cognitive aging). This is critical because the ever growing healthy aging population will show declines in cognition that fall short of dementia but still impact functional abilities and independence. Maintaining good nicotinic system functioning throughout adulthood may lessen the cognitive symptoms of aging. At this time, it is not clear what the biological cause of age-related changes in cognition is. This study will examine the role of the nicotinic system in the healthy aging brain and examine its role in memory and thinking processes in older and younger adults.

2016-10-01

2021-12-01

2022-01-31

Completed

Early phase I

104

Inclusion Criteria: * Normal cognition, not demented, no mild cognitive impairment. IQ greater than 80. Exclusion Criteria: * Current use of barbiturates, rifampin, insulin, carbamezepine, oral hypoglycemics, antidepressants, diabetes, or untreated thyroid disease. * In addition, the following exclusions are specific for the challenge drugs: heavy alcohol or coffee use, significant cardiovascular disease, ischemic heart disease, asthma, chronic obstructive pulmonary disease, active peptic ulcer, hyperthyroidism, pyloric stenosis, narrow angle glaucoma, epilepsy, or current Axis I psychiatric disorders. * Current use of centrally active drugs and drugs with cholinergic properties. A minimum of 14 days will elapse between discontinuing centrally active or psychoactive agents and this study.

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2023-05-09