# Characterization of Hippocampal Neural Activity in Evidence Accumulation and Decision-Making

> **NIH NIH F32** · PRINCETON UNIVERSITY · 2020 · $67,446

## Abstract

Characterization of Hippocampal Neural Activity in Evidence
Accumulation and Decision-Making
Project Summary/Abstract
In an ever-changing environment, the ability to accumulate and evaluate evidence is crucial for optimal
decision-making. The hippocampus is thought to embody a cognitive map and has been well-studied in
navigation and foraging tasks. However, it is unknown how the hippocampus behaves when evidence for
decision-making must be accumulated over time. We will use calcium imaging to measure neural activity from
hundreds of CA1 neurons simultaneously in mice navigating a virtual T-maze with noisy visual cues that inform
the animal of the correct decision (left or right turn) at the end of the maze. Our first aim will be to build a
comprehensive model of CA1 neural activity during this task that can account for the primary variables of
evidence and place, possibly multiplexed with other perceptual and behavioral variables. Promising preliminary
evidence suggests that CA1 neurons encode spatial information that is modulated by the amount of evidence
that has been received. In addition to single cell activity, evidence also suggests that CA1 neurons can
organize into multiple sequences in the same environment. Our second aim is to evaluate whether the
sequential nature of CA1 population activity holds task-relevant information beyond individual neuron activity.
Our third aim is to investigate the biophysical underpinnings of these sequences and whether their formation
takes place as a causal result of population activity in the CA1. To achieve these goals, we will utilize rodent
virtual reality behavior, multidimensional analysis tools to investigate the coordinated activity of large
populations of neurons, in addition to combining cellular-resolution optogenetic activation/inhibition
simultaneously with 2-photon calcium imaging. Together, these experiments will establish a role for the
hippocampus in a previously unstudied context. Beyond the significance for basic science research,
understanding the neural processes behind evidence accumulation and decision-making also has important
implications in the management of psychiatric and neurological disorders, such as obsessive-compulsive
disorder, addiction, or attention deficit hyperactivity disorder, in which these functions are disrupted.

## Key facts

- **NIH application ID:** 9925650
- **Project number:** 5F32MH119749-02
- **Recipient organization:** PRINCETON UNIVERSITY
- **Principal Investigator:** Horng-An Edward Nieh
- **Activity code:** F32 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $67,446
- **Award type:** 5
- **Project period:** 2019-05-01 → 2022-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9925650

## Citation

> US National Institutes of Health, RePORTER application 9925650, Characterization of Hippocampal Neural Activity in Evidence Accumulation and Decision-Making (5F32MH119749-02). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/9925650. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*