NCT03822910

Hippocampal Memory Circuits in Delusions

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 212 (actual)
• Sponsor: NYU Langone Health · Academic / Other
• Sex: All
• Age: 16 Years – 35 Years
• Healthy volunteers: Not accepted

Summary

This study will investigate dentate gyrus (DG) and hippocampal CA3 sub field function, using the pattern separation paradigm, as reflected by the difference in brain activation in response to same-as-previously- seen (OLD) vs. similar-to-previously-seen (SIM) objects in first episode psychosis (FEP) subjects before and after anti psychotic treatment and in matched healthy controls (HC). The current study uses three novel high-resolution task-based and post-encoding resting fMRI measures to probe hippocampal circuitry in delusions. It will also study CA1 function, using a sequential associative mismatch paradigm, as reflected by activation of CA1 in response to mismatching information compared to memory of that stimulus in FEP subjects before and after antipsychotic treatment and in matched HC. Finally, this study will evaluate plasticity of hippocampal intrinsic functional connectivity (IFC) in response to memory consolidation, using an encoding-plasticity paradigm, in FEP subjects before and after anti psychotic treatment and in matched HC. For each of the three imaging projects, a total of 50 FEP subjects and 50 matched healthy controls (HC) will be studied; hence, 300 subjects will be studied over 5 years. Within each paradigm, medication-naive FEP subjects will be studied at baseline and 8 weeks after starting anti psychotic medication. HC participants will be studied at baseline and 8 weeks later but will not receive any treatment.

Conditions

• Psychosis

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Pattern Separation Paradigm	Will be used to investigate dentate gyrus (DG) and hippocampal CA3 subfield as reflected by the difference in brain activation in response to same as previously seen (OLD) vs similar to previously seen (SIM) objects in first episode (FEP) subjects before and after treatment.
DIAGNOSTIC_TEST	Sequential Associative Mismatch Paradigm	used to reflect activation of CA1 in response to mismatching information compared to memory of the stimulus in FEP subjects before and after antipsychotic treatment and in matched Healthy Control (HC).
DIAGNOSTIC_TEST	Encoding Plasticity Paradigm	Used to evaluate plasticity of hippocampal Intrinsic Functional Connectivity (IFC) in response to memory consolidation in FEP subjects before and after antipsychotic treatment and in matched HC.

Timeline

• Start date: 2019-07-13
• Primary completion: 2023-08-12
• Completion: 2023-08-12
• First posted: 2019-01-30
• Last updated: 2024-04-30

Locations

3 sites across 2 countries: United States, China