Gender	Male
E-mail	john.morrison@mssm.edu
Education and Training	Ph.D., Johns Hopkins University
Awards	2007 - 2017 Merit Award on Glutamate Receptors in Aging Cortical Circuits NIH
	2000 - 2010 Program Project Grant on Estrogen and the Aging Brain NIH

In October, 2006, Dr. Morrison stepped down as Chair of Neuroscience to assume the position of Dean of Basic Sciences and the Graduate School of Biological Sciences at Mount Sinai School of Medicine.

Dr. Morrison is also Professor of Neuroscience and the Willard T. C. Johnson Professor of Geriatrics and Adult Development in Neurobiology of Aging.

Visit Dr. John Morrison's Lab for more information.

Education and Training	Ph.D., Johns Hopkins University

Specific Clinical/Research Interest: Neurobiology of cognitive aging. Cortical organization, synaptic plasticity, and synaptic alterations with aging. Steroid effects on cortical circuitry, synaptic organization, and function. Neurodegeneration.

Current Students: PhD: Athena Wang, Erik Bloss, Megan Bailey. MD/PhD: Dani Dumitriu, Kimberly Kwei.

Postdoctoral Fellows: Rebecca Shansky and Yuko Hara.

Research Personnel: Lab Manager: Bill Janssen; Research Assistants: Shannon Wadsworth, Dan Ohm, and Rishi Puri.

Current Research
Neurobiology of Aging, Cellular and Synaptic Organization of Cerebral Cortex, Estrogen and the Aging Brain, Cognitive Aging, and Neurodegenerative Disorders
Our research program includes several related components, with the three primary areas being the cellular and synaptic organization of cerebral cortex, selective vulnerability in neurodegenerative disorders, and age-related alterations in glutamate receptor-mediated cortical circuits. These efforts involve cellular neuropathologic analyses of human brain, experimental and neuropathologic analyses of non-human primate and rat cortex, and detailed analyses of genetically manipulated mice. In both neocortex and hippocampus, we are particularly interested in determining the molecular and structural nature of age-related alterations in synaptic plasticity that lead to compromised cognitive function. We are particularly interested in age-related synaptic alterations and how the mechanism of such alterations differs from the degenerative cascade of Alzheimer’s disease. Virtually all of our microscopic analyses are quantitative in nature and through collaborations with cognitive neuroscientists, we are able to link quantitative cellular and synaptic measurements with cognitive performance in the same subjects.

Our studies on glutamate receptor-mediated circuits have focused on both neocortex and hippocampus of primates and rodents. Recently, we have been particularly interested in the cellular and molecular events underlying the functional decrements often seen in normal aging, particularly age-related memory impairment. In contrast to Alzheimer's Disease, cell loss is not likely to be a significant contributor to functional decline in normal aging. Shifts in expression and distribution of key molecules (i.e., glutamate receptors) in otherwise intact circuits, however, do appear to be occurring in aging, and in a manner that would have profound effects on synaptic transmission in key hippocampal and neocortical circuits. These alterations in the molecular constituents of the synapse occur against a background of structural alterations of the spines and synapses that also impact function. Our interests in aging and synaptic plasticity have been ex panded over the years to include research programs on the effects of stress on cortical function and plasticity, as well as the links between neuronal aging and endocrine senescence. These studies have revealed synaptic attributes in prefrontal cortex that are altered with aging yet rescued by estrogen treatment, thereby protecting against cognitive decline in aged female monkeys. We are continuing to pursue the mechanistic links between age-related decreases in estrogen levels (i.e., menopause), glutamate receptors, and cortical circuits in behaviorally and hormonally characterized aged non-human primates, with a particular focus on prefrontal cortex and related cognitive functions.

Goldwater DS, Pavlides C, Hunter RG, Bloss EB, Hof PR, McEwen BS, Morrison JH. Structural and functional alterations to rat medial prefrontal cortex following chronic restraint stress and recovery. Neuroscience 2009; 164: 798-808.

Radley JJ, Rocher AB, Rodriguez A, Ehlenberger DB, Dammann M, McEwen BS, Morrison JH, Wearne SL, Hof PR. Repeated stress alters dendritic spine morphology in the rat medial prefrontal cortex. J. Comp. Neurol 2008; 507(1): 1141-1150.

Yildirim M, Janssen WM, Tabori NE, Adams MM, Yuen GS, Akama KT, McEwen BS, Milner TA, Morrison JH. Estrogen and aging affect synaptic distribution of phosphorylated LIM kinase (pLIMK) in CA1 region of female rat hippocampus. Neuroscience 2008; 152(2): 360-370.

Hao J, Rapp PR, Janssen WM, Morrison JH, Lasley BL, Hof PR, Lou W. Interactive effects of age and estrogen on cognition and pyramidal neurons in monkey prefrontal cortex. Proc. Natl. Acad. Sci. USA 2007; 104: 11465-11470.

Morrison JH, Gore AC, Schmidt PJ, Brinton RD. Estrogen, menopause, and the aging brain: How basic neuroscience can inform hormone therapy in women. J. Neurosci 2006; 26(41): 10332-10348.

Hao J, Rapp PR, Leffler AE, Leffler SR, Janssen WG, Lou W, Mc Kay H, Roberts JA, Wearne SL, Hof PR, Morrison JH. Estrogen alters spine number and morphology in prefrontal cortex of aged female rhesus monkeys. J Neurosci 2006 Mar; 26(9): 2571-2578.

Moga DE, Morrison JH, Shapiro ML. Bidirectional redistribution of AMPA but not NMDA receptors after perforant path stimulation in the adult rat hippocampus in vivo. Hippocampus 2006; 16(11): 990-1003.

Radley JJ, Sisti HM, Hao J, Rocher AB, Mc Call T, Hof PR, Mc Ewen BS, Morrison JH. Chronic behavioral stress induces apical dendritic reorganization in pyramidal neurons of the medial prefrontal cortex. Neuroscience 2004; 125(1): 1-6.

Wu CC, Chawla F, Games D, Rydel RE, Freedman S, Schenk D, Young WG, Morrison JH, Bloom FE. Selective vulnerability of dentate granule cells prior to amyloid deposition in PDAPP mice: digital morphometric analyses. Proc Natl Acad Sci U S A 2004 May; 101(18): 7141-7146.

Hof PR, Morrison JH. The aging brain: morphomolecular senescence of cortical circuits [review]. Trends Neurosci 2004 Oct; 27(10): 607-13.