Dr. Lynn Hasher
Research Focus
The work in my laboratory continues to focus on inhibitory control over the contents of working memory - or over momentary consciousness. Most recently we have shown that classic measures of working memory do not measure how much information can be held onto. Rather they measure the amount of task-relevant information that is held. People with small working memory spans tend to continue to deal with no longer relevant information while people with large working memory spans focus only on the currently relevant information. Older adults' spans tend to be reduced in size, relative to that of younger adults' spans, but that reduction is because older adults continue to consider no longer relevant information, while younger adults do not. The theory that guides this work is published in a chapter in the Attention and Performance volume (2000).Other work focuses on the degree to which performance, particularly that of older adults' is impacted by the time at which they are tested. We continue to show that on many tasks (e.g., including span tasks, attention tasks, memory tasks and some neuropsychological tests), the performance of older adults is far better at their optimal time (usually the morning) than it is at their nonoptimal time (later in the day). We attribute this to the operation of circadian arousal patterns that impact on inhibitory control, but not on excitatory control.
Select Publications
- Rabi R, Chow R, Paracha S, Hasher L, Gardner S, Anderson ND, Alain C. (2022). Time of day effects on inhibitory functioning: Cognitive and neural inhibitory evidence of sundowning in individuals with amnestic mild cognitive impairment. Journal of Alzheimer’s Disease, 90, 869-890.
- Rabi R, Chow R, Paracha S, Hasher L, Gardner S, Anderson ND, Alain C. (2022). Cognitive and neural inhibitory sundowning in individuals with amnestic mild cognitive impairment. Journal of Alzheimer’s Disease, 90, 869-890.
- Chow R, Rabi R, Paracha S, Vasquez BP, Hasher L, Alain C, Anderson ND. (2022). Inhibitory deficits in single- and multiple-domain amnestic mild cognitive impairment. Journal of Gerontology: Psychological Sciences, 77, 71-83.
- Alain C, Chow R, Lu J, Rabi R, Sharma V, Shen D, Anderson ND, Binns M, Hasher L, Yao D, Freedman M. (2022). Aging enhances neural activity in auditory, visual, and somatosensory cortices: The common cause hypothesis revisited. The Journal of Neuroscience, 42, 264-275.
