Exploiting development to evaluate auditory encoding of amplitude modulation.

Title

Exploiting development to evaluate auditory encoding of amplitude modulation.

Creator

Rosen Merri J; Semple Malcolm N; Sanes Dan H

Publisher

The Journal of neuroscience : the official journal of the Society for Neuroscience

Date

2010
2010-11

Description

During development, detection for many percepts matures gradually. This provides a natural system in which to investigate the neural mechanisms underlying performance differences: those aspects of neural activity that mature in conjunction with behavioral performance are more likely to subserve detection. In principle, the limitations on performance could be attributable to either immature sensory encoding mechanisms or an immature decoding of an already-mature sensory representation. To evaluate these alternatives in awake gerbil auditory cortex, we measured neural detection of sinusoidally amplitude-modulated (sAM) stimuli, for which behavioral detection thresholds display a prolonged maturation. A comparison of single-unit responses in juveniles and adults revealed that encoding of static tones was adult like in juveniles, but responses to sAM depth were immature. Since perceptual performance may reflect the activity of an animal's most sensitive neurons, we analyzed the d prime curves of single neurons and found an equivalent percentage with highly sensitive thresholds in juvenile and adult animals. In contrast, perceptual performance may reflect the pooling of information from neurons with a range of sensitivities. We evaluated a pooling model that assumes convergence of a population of inputs at a downstream target neuron and found poorer sAM detection thresholds for juveniles. Thus, if sAM detection is based on the most sensitive neurons, then immature behavioral performance is best explained by an immature decoding mechanism. However, if sAM detection is based on a population response, then immature detection thresholds are more likely caused by an inadequate sensory representation.

Subject

Female; Male; Animals; Acoustic Stimulation/methods; Age Factors; Auditory Perception/*physiology; Gerbillinae; Auditory Threshold/*physiology; Auditory Cortex/*growth & development; Auditory Pathways/*growth & development

Rights

Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).

Pages

15509–15520

Issue

46

Volume

30

Citation

Rosen Merri J; Semple Malcolm N; Sanes Dan H, “Exploiting development to evaluate auditory encoding of amplitude modulation.,” NEOMED Bibliography Database, accessed December 4, 2024, https://neomed.omeka.net/items/show/5002.