John Morrison, PhD

Dr. Morrison’s research program focuses on the cellular, molecular, and synaptic organization of hippocampus and neocortex. Much of this work has been focused on the age-related cellular, molecular, and synaptic events that lead to cognitive decline, as well as the cellular pathology of Alzheimer’s Disease (AD) and other neurodegenerative disorders. We have identified multiple synaptic attributes in prefrontal cortex (PFC) of the rhesus monkey that are highly vulnerable to aging and their loss is strongly correlated with cognitive decline. Many of these attributes are protected by cyclical estradiol treatment (E2T) that also protects against age-related cognitive decline. We have also revealed several reflections of synaptic aging in rhesus monkey hippocampus that lead to age-related cognitive decline, and interestingly, the vulnerable synapses in hippocampus bear little resemblance to the patterns of vulnerability in PFC, demonstrating independent region-specific mechanisms of synaptic aging. Through these synaptic analyses we are developing a molecular and structural profile of Synaptic Health. We are now developing and characterizing both tau and Ab oligomer based monkey models of AD, as well as a model of HIV-associated Neurocognitive Disorder (HAND). We are now applying the same microscopic techniques to analyze the effects of SAR-CoV-2 on the brain of young and aged monkeys, as well as developmental pathology induced by Zika and fetal brain injury induced by intrauterine inflammation, bringing our focus to both ends of the health span with respect to the interface between neuroscience and infectious diseases.

Graduate group affiliations:

• Neurosciences Graduate Group (GNES)