An Emergent Discriminative Learning Is Elicited During Multifrequency Testing.
Xingui Zhang1, Xianhua Ye1, Rui Cheng1
1Department of Physiology, School of Basic Medical Sciences, Key Laboratory of Psychiatric Disorders of Guangdong Province, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China.
Frontiers in Neuroscience
|December 12, 2019
Summary
Auditory fear conditioning involves emergent discriminative learning, where mice distinguish conditioned sounds. This learning relies on the medial prefrontal cortex (mPFC) and primary auditory cortex (A1) neural pathways.
Area of Science:
- Neuroscience
- Auditory System Research
- Learning and Memory
Background:
- Auditory-conditioned fear learning typically involves a freezing response.
- The role of specific sound frequencies and emergent discriminative learning in auditory fear conditioning is not well understood.
- The neural circuits underlying auditory fear discrimination remain to be elucidated.
Purpose of the Study:
- To investigate whether emergent discriminative learning occurs in auditory fear conditioning.
- To identify the specific brain nuclei and pathways involved in this discriminative learning.
- To determine the functional roles of the medial prefrontal cortex (mPFC) and primary auditory cortex (A1) in auditory fear discrimination.
Main Methods:
- Behavioral assays to assess auditory discrimination in mice after fear conditioning.
- Electrophysiological recordings to measure neuronal responses in the mPFC and A1.
- Pharmacological manipulations (muscimol, lidocaine) to silence specific brain regions (mPFC, A1).
Main Results:
- Mice exhibited emergent discriminative learning, distinguishing conditioned auditory stimuli (CS) from unrelated frequencies (UFs) after fear conditioning.
- Medial prefrontal cortex (mPFC) neuronal responses to the CS were enhanced post-conditioning.
- Silencing the mPFC or primary auditory cortex (A1) blocked emergent discriminative learning, indicating their necessity.
Conclusions:
- Emergent discriminative learning is a key feature of auditory fear conditioning.
- The medial prefrontal cortex (mPFC) and primary auditory cortex (A1) are critical neural substrates for auditory fear discrimination.
- This study elucidates the neural mechanisms underlying the ability to discriminate between learned and novel auditory cues in a fear context.
