John H.R. Maunsell, PhD

Our research is aimed at understanding how neuronal signals in visual cerebral cortex generate perceptions and guide behavior. Our approach is to record from individual neurons in trained, behaving monkeys and mice while they perform visual tasks.



Much of our work is directed at understanding how paying attention to specific visual targets affects the way that they are represented in the brain, and how changes in the sensory representation caused by attention relate to changes in perception and behavior. We have shown that attention increases the strength of neuronal responses without changing their selectivity, effectively representing the attended stimulus as if it were more intense than it really is. Paired measurements of neuronal responses and behavioral performance have shown that much of the behavioral advantage conferred by attention may be explained by this change it causes in the sensory representation, rather than decision processes.



Another line of research has been exploring the more general question of how the activity of given neurons contributes to specific visual behaviors. Measurements of the trial-to-trial correlation between the strength of a neuron's responses to a weak stimulus and the animal's performance detecting that stimulus have shown that different neurons contribute to a greater or lesser degree to particular behaviors depending on which stimuli they are most sensitive to.



We also use electrical and optical microstimulation to explore how different regions in visual cortex contribute to visual perceptions. By measuring the stimulus strength needed to produce a just-detectable stimulus in different cortical areas, we have found that all regions of cerebral cortex are comparable in their ability to produce detectable percepts.

Duke University
Durham, NC
BS - Zoology

California Institute of Technology
Pasadena, CA
PhD - Biology

Massachusetts Institute of Technology
Cambridge, MA
Postdoc - Psychology

Normalization in mouse primary visual cortex.
Normalization in mouse primary visual cortex. PLoS One. 2023; 18(12):e0295140.
PMID: 38109430

Rodent attention: Probing the mouse mind with reverse correlation.
Rodent attention: Probing the mouse mind with reverse correlation. Curr Biol. 2023 09 11; 33(17):R916-R918.
PMID: 37699352

Temporal weighting of cortical and subcortical spikes reveals stimulus dependent differences in their contributions to behavior.
Temporal weighting of cortical and subcortical spikes reveals stimulus dependent differences in their contributions to behavior. bioRxiv. 2023 Aug 24.
PMID: 37662213

Increments in visual motion coherence are more readily detected than decrements.
Increments in visual motion coherence are more readily detected than decrements. J Vis. 2023 05 02; 23(5):18.
PMID: 37223942

Normalization in mouse primary visual cortex.
Normalization in mouse primary visual cortex. bioRxiv. 2023 Apr 18.
PMID: 37131716

Neuronal correlates of selective attention and effort in visual area V4 are invariant of motivational context.
Neuronal correlates of selective attention and effort in visual area V4 are invariant of motivational context. Sci Adv. 2022 06 10; 8(23):eabc8812.
PMID: 35687684

Perceptual Weighting of V1 Spikes Revealed by Optogenetic White Noise Stimulation.
Perceptual Weighting of V1 Spikes Revealed by Optogenetic White Noise Stimulation. J Neurosci. 2022 04 13; 42(15):3122-3132.
PMID: 35232760

Single trial neuronal activity dynamics of attentional intensity in monkey visual area V4.
Single trial neuronal activity dynamics of attentional intensity in monkey visual area V4. Nat Commun. 2021 03 31; 12(1):2003.
PMID: 33790282

An Open Resource for Non-human Primate Optogenetics.
An Open Resource for Non-human Primate Optogenetics. Neuron. 2020 12 23; 108(6):1075-1090.e6.
PMID: 33080229

The Mind of a Mouse.
The Mind of a Mouse. Cell. 2020 09 17; 182(6):1372-1376.
PMID: 32946777

View All Publications

Member
National Academy of Sciences
2021

Golden Brain Award
Minerva Foundation
2020

Member
Dana Alliance for Brain Initiatives
2018 - 2022

Elected Fellow
American Academdy of Arts and Science
2014

Astor Visiting Lecturer
Oxford University
2008

Elected Fellow
American Academy for the Advancement of Science
2002

Development Award
McKnight Foundation
1991 - 1993

Young Investigator Award
Office of Naval Research
1986 - 1989

Outstanding PhD Thesis Award
Intra-Science Research Foundation
1982