Chinese Journal of Physiology

ORIGINAL ARTICLE
Year
: 2019  |  Volume : 62  |  Issue : 6  |  Page : 245--255

Sex differences and the modulating effects of gonad intactness on behavioral conformity in a mouse model


Chianfang G Cherng1, Lung Yu2 
1 Education Center of Humanities and Social Sciences, National Yang-Ming University, Taipei, Taiwan
2 Department of Physiology; Institute of Behavioral Medicine, National Cheng Kung University College of Medicine, Tainan, Taiwan

Correspondence Address:
Prof. Chianfang G Cherng
Education Center of Humanities and Social Sciences, National Yang-Ming University, Taipei 11221
Taiwan
Prof. Lung Yu
Department of Physiology, National Cheng Kung University College of Medicine, Tainan 70101; Institute of Behavioral Medicine, National Cheng Kung University College of Medicine, Tainan 70101
Taiwan

Although gender differences in conformity are noticed in human studies, cultural norms and psychosocial factors inevitably affect such differences. Biological factors, especially the gonadal hormones and the brain regions involved, contributing to the sex differences in behavioral conformity remained scarcely explored. To prevent psychosocial and cultural norm confounds, intact and gonadectomized male and female mice were used to assess the modulating effects of gonadal hormones on behavioral conformity and such conformity-related brain regions using an approach of choice paradigm. Intact and gonadectomized mice' choices for the nonrewarded runway were assessed when these experimental mice were alone versus with a group, consisting of three same-sex noncagemates choosing the respective experimental mice' nonrewarded runway, in a double-J-shaped maze test. Although male and female mice exhibited comparable rewarded runway choices at the conclusion of the operant training procedures and in the test individually, male mice demonstrated greater conformity index as compared to female mice when group tested. Gonadectomy, done at their 4 or 9 weeks of age, decreased males' conformity index but did not affect females' when both sexes were group tested. Such gonadectomy did not affect the conditioning or conformity index when tested individually in either sex. Female mice had higher serum corticosterone (CORT) levels when group tested as compared to the female mice tested individually and male mice. Finally, the number of FOS-staining cells in high conformity-displaying mice was found less than it in the low conformity-performing mice in the nucleus accumbens. Taken together, we conclude that testis-derived hormones, at least, play a role in enhancing behavioral conformity in male mice. CORT and nucleus accumbal neuronal activity deserve further investigation for their involvement in behavioral conformity.


How to cite this article:
Cherng CG, Yu L. Sex differences and the modulating effects of gonad intactness on behavioral conformity in a mouse model.Chin J Physiol 2019;62:245-255


How to cite this URL:
Cherng CG, Yu L. Sex differences and the modulating effects of gonad intactness on behavioral conformity in a mouse model. Chin J Physiol [serial online] 2019 [cited 2020 Jan 27 ];62:245-255
Available from: http://www.cjphysiology.org/article.asp?issn=0304-4920;year=2019;volume=62;issue=6;spage=245;epage=255;aulast=Cherng;type=0