Clinical Research Directory

Inclusion Criteria: Participants in behavioral studies must be: * healthy and between the ages of 18-35 years old * native English speakers * right-handed. Participants in fMRI studies must be: * healthy and between the ages of 18-80 years old * native English speakers * right-handed. Exclusion Criteria: For behavioral studies: \- Potential participants will be informed that use of psychoactive drugs, mental health disorders, and chronic or temporary sleep deficits (an average of less than 6 hours of sleep over the past month or less than 4 hours of sleep the night prior to the experimental session) are reasons for exclusion because of the potential influence on cognitive functioning. For fMRI studies: * For some sub-studies, individuals older than age 35 will be excluded because of potential differences in cognitive and brain function across age groups that are beyond the scope of the proposed studies. * Individuals will be informed that use of psychoactive drugs, mental health disorders, and chronic or temporary sleep deficits (an average of less than 6 hours of sleep over the past month or less than 4 hours of sleep the night prior to the experimental session) are reasons for exclusion because of the potential influence on cognitive functioning.