Related Experiment Video
Updated: May 12, 2026
10:53
Optogenetic Stimulation of the Auditory Nerve
Published on: October 8, 2014
Visual behaviour mediated by retinal projections directed to the auditory pathway
L von Melchner1, S L Pallas, M Sur
1Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge 02139, USA.
Nature
|April 29, 2000
Summary
In ferrets, rerouting visual input to the auditory cortex created a functional visual area. This demonstrates that extrinsic inputs significantly instruct a neocortical region's perceptual modality.
Area of Science:
- Neuroscience
- Developmental Neuroscience
- Sensory Processing
Background:
- Cortical development involves intrinsic and extrinsic factors shaping functional areas.
- The role of extrinsic inputs in determining a cortical area's modality is debated.
Purpose of the Study:
- To investigate if redirected visual input can induce visual perception and behavior in the auditory cortex.
- To determine the extent to which extrinsic inputs instruct perceptual modality.
Main Methods:
- Neonatal ferrets underwent surgical redirection of retinal projections to the auditory thalamus.
- Auditory cortex responses and behavioral responses to visual stimuli presented via the rewired pathway were analyzed.
Main Results:
- Rewired ferrets exhibited visually responsive cells and retinotopic maps in the auditory cortex.
- These ferrets demonstrated visual behavioral responses to light stimuli, perceiving them as visual, not auditory.
- Discrimination of grating spatial frequencies was possible via the rewired pathway, albeit with reduced acuity.
Conclusions:
- Extrinsic inputs play a crucial role in instructing the perceptual modality of neocortical areas.
- Functional visual capabilities can be established in a non-visual cortical region through cross-modal projections.
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01:32The Retina
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01:24Vision
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01:15Auditory Pathway
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01:26Visual System
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01:17Auditory Perception
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