Skip to content

Hippocampal Memory Circuits in Delusions

Hippocampal Memory Circuits in Delusions

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT03822910
Enrollment
212
Registered
2019-01-30
Start date
2019-07-13
Completion date
2023-08-12
Last updated
2024-04-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Psychosis

Brief 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.

Interventions

DIAGNOSTIC_TESTSequential 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_TESTPattern 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_TESTEncoding 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.

Sponsors

National Institutes of Health (NIH)
CollaboratorNIH
NYU Langone Health
Lead SponsorOTHER

Study design

Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
16 Years to 35 Years
Healthy volunteers
No

Inclusion criteria

* Males and females 16 to 35 years of age, inclusive, at the time of informed consent * Right-handed * Must have experienced a first episode of non-affective psychosis over the past five years * Must exhibit a persistence of delusions for at least 4 days per week for at least 4 weeks in the absence of psychotomimetic substance use or other potential organic etiologies, including epilepsy or significant head trauma. * Must score at least a 2 (mild to moderate) on the Amount of preoccupation with delusions and Conviction items on the Psychotic Symptom Rating Scale (PSYRATS).

Exclusion criteria

* Diagnosis of major mood disorder or other Axis I disorder other than Schizophrenia, Schizoaffective Disorder or Schizophreniform Disorder. * Significant medical or neurological illness by history or physical exam including seizure disorder, history of loss of consciousness related to head trauma or developmental disorder including mental retardation. * Metal implants, pacemaker, or other metal in the body or medicinal patch. * History of claustrophobia. * Currently taking any anti psychotic medication (within 4 weeks).

Design outcomes

Primary

MeasureTime frame
The difference in CA1 activation between a mismatch and an intact trial in FEP subjects after 8 weeks of antipsychotic treatment and the correlation of this change with change in delusions as measured by the Psyrats-D total score.8 Weeks
Change in hippocampus-to-VTA (hip-VTA) IFC and hip-to-lateral occipital complex (hip-LO) IFC, from pre- to post- encoding during the encoding-plasticity paradigm, between FEP and HC.8 Weeks
Change in (a) hip-VTA IFC and (b) hip-LO IFC, from pre- to post- encoding during the encoding-plasticity paradigm8 Weeks
correlation of change (a) hip-VTA IFC and (b) hip-LO IFC with change in delusional severity measured by the Psyrats-D total score.8 Weeks

Countries

China, United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026