Schizophrenia has a lifetime prevalence of 1% in the general population. It is positive symptoms including delusions and hallucinations, negative symptoms including anhedonia and avolition, and cognitive symptoms including memory deficits and social impairment. Past studies have found structural and functional changes in the hippocampus. Structural studies have illustrated decreased hippocampal volume in schizophrenia. characterized by Functional MRI studies have revealed resting- state hyperactivity of the hippocampus and have implicated glutamate as a driver of increase CBV. Schizophrenia is also associated with abnormal recruitment of the hippocampus during memory tasks. Some of these structural and functional results have been localized to specific regions of the hippocampus. However, it is unclear when in the natural history of the disease the changes in hippocampal CBV and volume occur. We propose a cross-sectional study that investigates hippocampal CBV and volume in patients with first-episode psychosis and schizophrenia. We hypothesize that hippocampal CBV is increased but hippocampal volume is not affected in first-episode psychosis. We predict that hippocampal CBV will also be increased in schizophrenia, but hippocampal volume will be reduced. In a subset of patients, we will implement a non-invasive inflow-based vascular-space occupancy (iVASO) method. We hypothesize that this method will serve as a more sensitive marker by selectively measuring arterial CBV (instead of arterial and venous CBV). If our hypotheses hold true, CBV measurements may serve as a functional biomarker that precedes hippocampal volume changes seen in schizophrenia and could be used as a target for future pharmacological interventions.

Public Health Relevance

Structural and functional changes in the hippocampus in schizophrenia are well characterized; however, it is unclear when these changes occur. The proposed project will investigate which regions within the hippocampus are affected and when these changes occur.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30MH102846-03
Application #
9109053
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Chavez, Mark
Project Start
2014-08-01
Project End
2018-07-31
Budget Start
2016-08-01
Budget End
2017-07-31
Support Year
3
Fiscal Year
2016
Total Cost
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Neurosciences
Type
Schools of Medicine
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37240
Talati, Pratik; Rane, Swati; Donahue, Manus J et al. (2016) Hippocampal arterial cerebral blood volume in early psychosis. Psychiatry Res Neuroimaging 256:21-25
Rane, Swati; Talati, Pratik; Donahue, Manus J et al. (2016) Inflow-vascular space occupancy (iVASO) reproducibility in the hippocampus and cortex at different blood water nulling times. Magn Reson Med 75:2379-87
Talati, Pratik; Rane, Swati; Skinner, Jack et al. (2015) Increased hippocampal blood volume and normal blood flow in schizophrenia. Psychiatry Res 232:219-25
Talati, Pratik; Rane, Swati; Kose, Samet et al. (2014) Increased hippocampal CA1 cerebral blood volume in schizophrenia. Neuroimage Clin 5:359-64