We found that attraction to female odors emerges at postnatal day 37 in male Syrian hamsters.
We then measured the level of polysialylated neural cell adhesion molecule (PSA-NCAM) in numerous brain regions.
PSA-NCAM was selectively elevated in the posterodorsal medial amygdala, just before the emergence of opposite sex attraction
Serum T was unrelated to PSA-NCAM in the MePD, but was inversely related to it in the habenula and thalamus.
Depletion of polysialic acids from posterodorsal medial amygdala blocked the emergence of attraction to female odors.