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Related Experiment Video

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Author Spotlight: An Accurate and Quantitative Approach to Study Visual Feature Selectivity of the Optokinetic Reflex in Mice

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Published on: June 23, 2023

Renewed Attention on the Pupil Light Reflex.

Paola Binda¹, Paul D Gamlin²

¹Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.

Trends in Neurosciences

|July 12, 2017

Summary

Electrical stimulation of the frontal eye fields (FEF) in macaques influences the pupillary light reflex. This suggests prefrontal cortex involvement in basic reflex control, extending beyond visual processing.

Keywords:

attention frontal eye fields prefrontal cortex pupillary light reflex

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Area of Science:

Neuroscience
Ophthalmology
Cognitive Science

Background:

The frontal eye fields (FEF) are crucial for visual attention and eye movements.
The pupillary light reflex is a fundamental, involuntary response to light.
Previous research linked prefrontal cortex activity to attentional modulation of visual processing.

Purpose of the Study:

To investigate whether subthreshold electrical microstimulation of the macaque FEF affects the pupillary light reflex.
To explore the extent to which prefrontal cortical areas influence subcortical reflex circuits.

Main Methods:

Subthreshold electrical microstimulation was applied to the FEF in macaque monkeys.
The pupillary light reflex was measured under different stimulation conditions.
Behavioral and physiological responses were recorded.

Main Results:

Subthreshold electrical microstimulation of the FEF modulated the pupillary light reflex.
This modulation indicates a functional connection between the FEF and the neural circuitry controlling pupil response.
The findings demonstrate that FEF stimulation can alter a basic, subcortical reflex.

Conclusions:

The frontal eye fields (FEF) exert top-down control over the pupillary light reflex.
Attentional modulation by the prefrontal cortex extends to subcortical circuits.
This study reveals a novel link between higher cognitive functions and basic physiological reflexes.