# Cortical mechanisms mediating visual function and behavior

> **NIH NIH R01** · UNIVERSITY OF TEXAS AT AUSTIN · 2022 · $510,855

## Abstract

Project Summary
Intracellular recording from sensory cortex provides a window into the synaptic inputs that shape spiking
responses of individual cortical neurons, but until recently, this powerful technique has been limited to
anesthetized animals. By combining the unique expertise from our laboratories, we have developed a novel
technique that allow us to conduct, on a routine basis, reliable, whole-cell intracellular recording in primary
visual cortex (V1) of awake, behaving macaque monkeys. We combine intracellular recording with an array of
concomitant measurements that provide access to the state of the local network in which the neuron is
embedded as well as to the internal state of the animal. Using these techniques, we have access to both
subthreshold (membrane potentials, representing input) and suprathreshold (spikes, representing output)
responses of individual cortical neurons, while also utilizing the precise control of visual stimulation and the
subject’s behavioral state afforded by behaving primates.
Our ability to perform intracellular recording in awake, behaving primates opens the door to addressing three
fundamental questions with respect to the circuit-level mechanisms that mediate visual perception: (1) what
are the nature, sources, and behavioral consequences of the large neural variability of sensory cortical
neurons, (2) what is the contribution of internal state fluctuations to this variability, (3) what circuit models
can account for the observed neural variability during spontaneous and evoked responses?
To address these questions, in Aim 1 we will study the quantitative relationship between sub- and
suprathreshold activity during spontaneous and stimulus-evoked responses in V1 of fixating monkeys. This
will allow us to test the generality of previous findings from anesthetized animals. In Aim 2, we will examine
the relationship between the activity of single V1 neurons and perceptual decisions in monkeys that are
engaged in a demanding visual detection task. Specifically, we will examine how sub- and suprathreshold
responses are altered by changing the attentional and motivational states under which the stimulus is
presented. Finally, in Aim 3 we will test a novel set of circuit models that can account for our observed results
and guide future experiments.

## Key facts

- **NIH application ID:** 10486135
- **Project number:** 5R01EY024071-06
- **Recipient organization:** UNIVERSITY OF TEXAS AT AUSTIN
- **Principal Investigator:** Nicholas J Priebe
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $510,855
- **Award type:** 5
- **Project period:** 2014-08-01 → 2026-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10486135

## Citation

> US National Institutes of Health, RePORTER application 10486135, Cortical mechanisms mediating visual function and behavior (5R01EY024071-06). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10486135. Licensed CC0.

---

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