Preclinical Assays of Hippocampal-Prefrontal Cortical Circuit Engagement for Application in Therapeutic Development 

About This Grant

TITLE: Preclinical Assays of Hippocampal-Prefrontal Cortical Circuit Engagement for Application in Therapeutic Development FOA type: PAR-19-289: Abstract: The high failure rate of translating discovery science to positive clinical outcomes in the treatment of psychiatric diseases demonstrates the necessity of improving the efficiency and rigor of the therapeutic development pipeline. To this end, the critical importance of advancing the discovery of in vivo physiological and behavioral measures of the engagement of specific circuits for normal cognitive function has been acknowledged across funding initiatives. The hippocampus (HPC)-prefrontal cortical (PFC) circuit is critical for affective processing as well as higher cognitive functions and vulnerable in a number of mental health disorders. Although disrupted functional connectivity in the HPC-PFC circuit is a common feature of anxiety, bipolar disorder, schizophrenia, and autism, how local cellular interactions within this circuit manifest as large-scale temporal coordination to support higher cognitive functions remains unknown. Addressing this fundamental gap in our knowledge will establish a foundation for using circuit-based models for therapeutic target discovery and screening tools of novel drug efficacy. The long-term goal of this proposal, in line with the Funding Opportunity Announcement (PAR-19-289), is to enhance the therapeutic development pipeline for mental illness treatment by optimizing, evaluating, and mechanistically testing neurophysiological and behavioral measures of circuit engagement. The primary objective of this proposal, which is the first step towards achieving our goal, is to relate behavioral performance on the rodent analog on the Paired Associates Learning task (PAL), part of human Cambridge Neuropsychological Test Automated Batteries [CANTAB] assessment, and surface EEG recordings to invasive neurophysiological measures of neural coordination in the HPC-PFC circuit. Through an innovative series of experiments that integrate in vivo neurophysiological local field potential (LFP) recordings, circuit manipulation, surface EEG, and behavior, we will optimize, evaluate and mechanistically test novel noninvasive biomarkers of HPC-PFC circuit engagement by pursuing the following specific aims: 1) Optimize behavioral and non-invasive EEG biomarkers for inferring HPC-PFC circuit engagement and temporal coordination, 2) Evaluation of behavioral and non-invasive EEG biomarkers for determining HPC-PFC circuit engagement through pharmacological manipulation, and 3) Mechanistically test HPC-PFC projections as a driver of surface EEG organization. The proposed research is innovative because it integrates a clinically relevant behavioral task, designed to be analogous to human cognitive assessments, with surface EEG measures that translate across mammals. This will enable the optimization, evaluation, and testing of novel and translatable measures of HPC-PFC circuit engagement in the context of higher cognition and global neural organization. The significance of this contribution will be to provide novel diagnostic tools that can be used to enhance the therapeutic development pipeline for treating mental illness.