Testosterone and social context affect singing behavior but not song control region volumes in adult male songbirds in the fall.

Full Abstract

Testosterone (T) induces singing behavior and mediates changes in the sizes and neuroanatomical characteristics of brain regions controlling singing behavior (song control regions, SCRs) in songbirds. These effects may require the enzymatic conversion of T into androgenic and estrogenic metabolites by brain tissues and can be modulated by factors such as season and social context. Testosterone administration to adult male House Finches, Carpodacus mexicanus, in the spring increases the size of their SCRs. Here, we used males of this species to investigate effects of T and T metabolism on brain morphology and singing behavior in the fall. Birds received Silastic capsules containing androgens, estrogens, and/or inhibitors of androgenic action or estrogen synthesis to determine effects of these hormones on song rates and SCR volumes. We also manipulated the social environment by changing the number of birds in visual contact with each other. Testosterone treatment stimulated singing behavior in finches held in small, visually isolated groups and exposed to song playbacks. However, administration of T or T metabolites did not increase SCR sizes. The data suggest that photoperiodic condition and social context may modulate the effects of steroids on SCRs and singing behavior.

Author information

Author/s: Strand, C R (CR); Ross, M S (MS); Weiss, S L (SL); Deviche, P (P);

Affiliation: Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA 93407, USA. cstrand(-atsign-)calpoly.edu

Journal and publication information

Publication Type: Journal Article

Journal: Behavioural processes (Behav Processes), published in Netherlands. (Language: eng)

Reference: 2008-May; vol 78 (issue 1) : pp 29-37

Dates: Created 2008/03/17; Completed 2008/07/09;

PMID: 18206319, status: MEDLINE (last retrieval date: 2/18/2009, IMS Date: 18 Feb 2009 00:00:00)

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.