Background
Adolescence is considered a critical time of life for emotional development in humans.
During this period the amygdala, which regulates emotions, undergoes structural reorganization.
Auditory fear conditioning, a form of amygdala-dependent emotional learning, occurs
differently in juvenile and adult rodents. Because this learning is mediated by plastic
changes in the thalamic and cortical inputs to lateral amygdala (LA), we investigated
changes in synaptic properties of these inputs during juvenile-to-adult transition.
Methods
Whole-cell patch clamp recording in amygdala slices from juvenile and young adult
mice was conducted to investigate long-term potentiation and basal synaptic transmission
in the thalamic and cortical inputs to LA.
Results
We show that physiological differences develop between thalamic and cortical afferents
to LA during the juvenile-to-adult transition. Although in juvenile mice the two pathways
have similar properties, in young adult mice the thalamic pathway has reduced plasticity,
increased number of quanta released by a single action potential, and decreased proportion
of silent synapses.
Conclusions
Changes in thalamic but not cortical inputs to amygdala take place during late development
and might contribute to differences in auditory fear conditioning between juveniles
and adults.
Key Words
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Article Info
Publication History
Published online: August 25, 2009
Accepted:
July 7,
2009
Received in revised form:
July 6,
2009
Received:
March 20,
2009
Identification
Copyright
© 2009 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
