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Updated: Dec 23, 2025
12:03
A Method for Tracking the Time Evolution of Steady-State Evoked Potentials
Published on: May 25, 2019
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Experience-Dependent Coding of Time-Dependent Frequency Trajectories by Off Responses in Secondary Auditory Cortex
Kelly K Chong1,2, Dakshitha B Anandakumar1,2, Alex G Dunlap1,2
1Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332.
Summary
Neural responses in the auditory cortex track subtle frequency changes in sounds. Specific "Off" responses in secondary auditory cortex (A2) adapt with experience to better interpret meaningful pitch trajectories.
Area of Science:
- Neuroscience
- Auditory Perception
- Animal Behavior
Background:
- Time-dependent frequency trajectories in sounds are crucial for conveying meaning across species.
- Understanding neural encoding of dynamic sound features and its plasticity is essential for auditory processing.
- The role of specific auditory cortical pathways in processing frequency trajectories remains unclear.
Purpose of the Study:
- To investigate neural tuning to subtle frequency trajectory variations in the mouse auditory cortex.
- To determine the role of experience-dependent plasticity in auditory cortical responses to behaviorally relevant sounds.
- To identify neural substrates critical for encoding dynamic frequency information in natural vocalizations.
Main Methods:
- Electrophysiological recordings in the auditory cortex of female mice.
- Stimulation with pure tones exhibiting subtle frequency modulations.
- Utilizing an ethologically inspired maternal mouse paradigm for vocalization learning.
Main Results:
- Auditory cortical neurons exhibit sensitivity to frequency trajectory variations as small as 1/24th of an octave.
- Late spiking responses ('Off' responses) after sound offset are more sensitive to frequency variations than during-sound responses.
- Experience-dependent plasticity in 'Off' responses was observed in the secondary auditory cortex (A2), but not core auditory cortex.
Conclusions:
- The mouse auditory cortex can accurately track fine frequency changes over time.
- A2 'Off' responses are plastic and can be modified by experience to enhance the representation of learned sound categories.
- These findings highlight the importance of dynamic neural coding in auditory perception and learning of behaviorally relevant sounds.
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