Keenan Walker, Ph.D.


Multimodal Imaging of Neurodegenerative Disease (MIND) Unit


251 Bayview Boulevard
Room 04B316
Baltimore, MD 21224


Research Topics

Dr. Walker's research program focuses on understanding the role of abnormal immune function and inflammation in Alzheimer's disease and late-life cognitive decline. He uses proteomic and genetic methods, brain-derived extracellular vesicles, and multimodal neuroimaging to investigate the link between chronic systemic inflammation, neuroinflammation, and neurologic endpoints using data from ongoing cohort studies, including the Baltimore Longitudinal Study of Aging (BLSA), Atherosclerosis Risk in Communities (ARIC) Study, Women's Health Initiative Memory Study (WHIMS), and the BIOCARD Study. Other areas of research focus include understanding the mechanisms leading to cognitive decline following critical illness and major infection, and evaluating how middle- and late-life vascular risk factors relate to dementia risk and structural brain changes.

Dr. Walker is the director of the Multimodal Imaging of Neurodegenerative Disease (MIND) Unit within the Laboratory of Behavioral Neuroscience.


Dr. Walker received his Ph.D. in clinical psychology from St. John's University. He completed his pre-doctoral internship in clinical neuropsychology at the University of California San Diego / VA San Diego Healthcare System before beginning an NIH-funded postdoctoral fellowship at Johns Hopkins University School of Medicine in age-related cognitive disorders. He began as an Assistant Professor of Neurology at Johns Hopkins in 2019 and soon after received funding for an NIH K23 career development award to study systemic inflammation and neuroinflammation in Alzheimer's disease. In 2020 he joined NIA's Laboratory of Behavioral Neuroscience as a Tenure-Track Investigator.

Selected Publications

  1. Walker KA, Chawla S, Nogueras-Ortiz C, Coresh J, Sharrett AR, Wong DF, Jack CR Jr, Spychalla AJ, Gottesman RF, Kapogiannis D. Neuronal insulin signaling and brain structure in nondemented older adults: the Atherosclerosis Risk in Communities Study. Neurobiol Aging. 2021;97:65-72.

  2. Kivimäki M, Walker KA, Pentti J, Nyberg ST, Mars N, Vahtera J, Suominen SB, Lallukka T, Rahkonen O, Pietiläinen O, Koskinen A, Väänänen A, Kalsi JK, Goldberg M, Zins M, Alfredsson L, Westerholm PJM, Knutsson A, Theorell T, Ervasti J, Oksanen T, Sipilä PN, Tabak AG, Ferrie JE, Williams SA, Livingston G, Gottesman RF, Singh-Manoux A, Zetterberg H, Lindbohm JV. Cognitive stimulation in the workplace, plasma proteins, and risk of dementia: three analyses of population cohort studies. BMJ. 2021;374:n1804.

  3. Lindbohm JV, Mars N, Walker KA, Singh-Manoux A, Livingston G, Brunner EJ, Sipilä PN, Saksela K, Ferrie JE, Lovering RC, Williams SA, Hingorani AD, Gottesman RF, Zetterberg H, Kivimäki M. Plasma proteins, cognitive decline, and 20-year risk of dementia in the Whitehall II and Atherosclerosis Risk in Communities studies. Alzheimers Dement. 2021.

  4. Sullivan KJ, Blackshear C, Simino J, Tin A, Walker KA, Sharrett AR, Younkin S, Gottesman RF, Mielke MM, Knopman D, Windham BG, Griswold ME, Mosley TH. Association of Midlife Plasma Amyloid-β Levels With Cognitive Impairment in Late Life: The ARIC Neurocognitive Study. Neurology. 2021.

  5. Tin A, Walker KA, Bressler J, Windham BG, Griswold M, Sullivan K, Wu A, Gottesman R, Fornage M, Coresh J, Sharrett AR, Folsom AR, Mosley TH. Association between Circulating Protein C Levels and Incident Dementia: The Atherosclerosis Risk in Communities Study. Neuroepidemiology. 2021;55(4):306-315.

This page was last updated on August 21st, 2021