John Maunsell

Albert D. Lasker Professor



Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior

The University of Chicago
5812 S Ellis Street, MC0912
Chicago, IL 60637 

Phone: (773) 702-3203
Office: P423
Lab: J446

Maunsell Lab website


Research Summary

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.

Select Publications

Ni, A.M., Ray, S., Maunsell, J.H.R. (2012) Tuned normalization explains the size of attention modulations. Neuron  73:803-813.

Histed, M.H., Ni, A.M., Maunsell, J.H.R. (2012) Insights into cortical mechanisms of behavior from microstimulation experiments. Progress in Neurobiology.

Glickfeld, L.L., Histed, M.H., Maunsell J.H.R., (2013) Mouse primary visual cortex is used to detect both orientation and contrast changes. Journal of Neuroscience 33:19416-19422. 

Histed, M.H., Maunsell, J.H.R. (2014) Cortical neural populations can guide behavior by integrating inputs linearly, independent of synchrony.  Proceedings of the National Academy of Science 111, E178–87.

Ray, S., Maunsell, J.H.R. (2015) Do gamma oscillations play a role in cerebral cortex? Trends in Cognitive Science 19:78-85.