Testosterone reduces amygdala-orbitofrontal cortex coupling.
Testosterone influences various aspects of affective behavior, which is mediated by different brain regions within the emotion circuitry. Previous neuroimaging studies have demonstrated that testosterone increases neural activity in the amygdala. To investigate whether this could be due to altered regulation of amygdala functioning which is thought to be mediated by the prefrontal cortex, we studied the effects of exogenous testosterone on the interaction between the amygdala and other brain regions. Healthy middle-aged women received a single nasal testosterone dose in a randomized, placebo-controlled, crossover manner, and performed an emotional face matching task while their brain activity was measured with functional MRI. The results show that testosterone rapidly reduced functional coupling of the amygdala with the orbitofrontal cortex, and enhanced amygdala coupling with the thalamus. This suggests that testosterone may reduce the regulatory control over the amygdala, or that testosterone shifts amygdala output away from the orbitofrontal cortex towards the thalamus. Testosterone also reduced functional coupling with the contralateral amygdala. Because interhemispheric amygdala coupling is lower in men than in women, this result suggests that circulating testosterone may contribute to this sexual dimorphism.
Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Kapittelweg 29, 6525 EN Nijmegen, The Netherlands. guido.vanwingen@donders.ru.nl
Guido
G
van Wingen
Claudia
C
Mattern
Robbert Jan
RJ
Verkes
Jan
J
Buitelaar
Guillén
G
Fernández
D000328:Adult; D000679:Amygdala / Q000187:drug effects*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008597:Menstrual Cycle / Q000502:physiology; D008875:Middle Aged; D009434:Neural Pathways / Q000187:drug effects; D017397:Prefrontal Cortex / Q000187:drug effects*; D011597:Psychomotor Performance / Q000187:drug effects; D011795:Surveys and Questionnaires; D013739:Testosterone / Q000097:blood / Q000494:pharmacology*
D013739:Testosterone