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Marilyn Hartman

Research Interests

My primary area of research is in the area of age-related declines in cognition (see below, however, for other research interests!). Although this research is informed by knowledge of cognitive neuropsychology, cognitive neuroscience, and clinical neuropsychology, the methods and approaches I utilize involve primarily experimental cognitive tasks, and the goal is to understand the information processing underpinnings of age differences in cognition.

In recent years, neuropsychological and cognitive studies have converged in identifying working memory as a key function in the reduced performance of older adults on tests of higher level cognition, including those dependent on prefrontal circuitry. My work has demonstrated the contribution of working memory deficits to age differences on a number of neuropsychological tests of frontal lobe function, and now primarily focuses on the components of working memory itself.

Declines in working memory appear to occur at the time of encoding rather than during maintenance or retrieval stages. A number of factors that might explain this phenomenon are under investigation in my laboratory:

1. Reduced consolidation of information into the short-term store. These studies test updating processes, bottlenecks in encoding, speed of encoding, and asymptotic levels of performance.
Tasks: Delayed Match to Sample Test, Temporal Integration Task, N-back Tasks

2. Declines in interference control in working memory. These studies test the effects of interference during and after encoding.
Tasks: Delayed Match to Sample Test, N-Back Tasks, Reading Span Tests

3. Reduced memory for contextual information and associations among stimuli. These studies assess age differences as well as look for similar mechanisms among these types of memory.
Tasks: Temporal memory, free recall, and recognition memory; N-Back Tasks; Delayed Match to Sample Test

4. Slowed processing speed. These studies test the extent to which generalized slowing can explain age differences in cognition.
Tasks: Perceptual Comparison Tests, Delayed Match to Sample Test, Temporal Integration Task

Other Research Activities

1. The relationship of neuropsychological function and declines in neuropsychological function to sleep structure and respiration during sleep in older adults. This study is a longitudinal study and represents an interdisciplinary approach, involving colleagues in the School of Nursing and Anesthesiology.

2. Volunteer caregiving in the community. This study examines the experiences and effectiveness of volunteers working together in teams to provide support to individuals and families facing serious illness and end of life. This study represents a partnership with a local nonprofit agency, Project Compassion.

3. The relationship between mindfulness and well-being (with Kimberly Coffey). This project focuses on identifying the mechanisms by which mindfulness leads to psychological benefits.