Crossmodal Induction of Thalamocortical Potentiation Leads to Enhanced Information Processing in the Auditory Cortex
Emily Petrus, et al.
Neuron 81(3):664–673, 5 February 2014
http://www.cell.com/neuron/abstract/S0896-6273(13)01091-X
Highlights:
•Visual deprivation improves frequency selectivity of A1 neurons
•Visual deprivation improves sound discrimination performance by A1 neurons
•Visual deprivation strengthens thalamocortical synapses in A1, but not in V1
•Crossmodal changes are more effectively recruited than unimodal changes in adult
Sensory systems do not work in isolation; instead, they show interactions that are specifically uncovered during sensory loss.
To identify and characterize these interactions, we investigated whether visual deprivation leads to functional enhancement in primary auditory cortex (A1).
We compared sound-evoked responses of A1 neurons in visually deprived animals to those from normally reared animals.
Here, we show that visual deprivation leads to improved frequency selectivity as well as increased frequency and intensity discrimination performance of A1 neurons.
Furthermore, we demonstrate in vitro that in adults visual deprivation strengthens thalamocortical (TC) synapses in A1, but not in primary visual cortex (V1).
Because deafening potentiated TC synapses in V1, but not A1, crossmodal TC potentiation seems to be a general property of adult cortex.
Our results suggest that adults retain the capability for crossmodal changes whereas such capability is absent within a sensory modality. Thus, multimodal training paradigms might be beneficial in sensory-processing disorders.
journalistic version:
Seeing Less Helps The Brain Hear More
February 05, 2014
http://www.npr.org/blogs/health/2014/02/05/272092118/seeing-less-helps-the-brain-hear-more
A few days in the dark can improve an animal’s hearing, scientists report this week in the journal Neuron.
This temporary loss of visual input seems to trigger favorable changes in areas of the brain that process auditory information.
Even when blindness occurs after that critical period in early childhood.