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Title: Age‐specific and context‐specific responses of the medial extended amygdala in the developing prairie vole
Abstract

The social needs of organisms change as they mature. Yet, little is known about the mechanisms that subserve processing social interactions or how these systems develop. The medial extended amygdala (meEA) is comprised of the medial bed nucleus of the stria terminalis (BSTm) and the medial amygdala (MeA). This neural complex holds great promise for understanding how the social brain processes information. We assessed expression of the immediate early genecFos and the enzyme tyrosine hydroxylase (TH) at three developmental time‐points (postnatal day [PND] 2, 9, and 21) to determine how developing prairie voles process familial social contact, separation, and reunion. We demonstrate that (1)BSTmcFos responses were sensitive to separation from family units atPND9 andPND21, but not atPND2; (2) MeAcFos responses were sensitive to reunion with the family, but only inPND21 pups; (3)BSTmTHneurons did not exhibit differential responses to social condition at any age; and (4) MeATHneurons responded strongly to social contact (remaining with family or following reunion), but only atPND21. Our results suggest that the sub‐units of the meEAbecome functionally responsive at different developmental time points, and are differentially activated in response to distinct social contexts. Overall, our results support the notion that interconnected regions of the meEAfollow divergent developmental timelines and are sensitive to distinct properties of social contexts.

 
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PAR ID:
10078724
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Developmental Neurobiology
Volume:
78
Issue:
12
ISSN:
1932-8451
Page Range / eLocation ID:
p. 1231-1245
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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