The evolved neurophysiological mechanisms linked to the acquired salience of visually perceived secondary sexual characteristics are not detailed, but the acquired salience is correlated with levels of reproductive hormones.

In other mammals the relative salience of visual cues associated with levels of reproductive hormones seems less than the salience of olfactory/pheromonal cues from the social environment. These olfactory/pheromonal cues are directly linked to hormones and behavior via reciprocity in a gene-cell-tissue-organ-organ system pathway.

Minimally, it seems important to mention in this article either the likely means by which the brain activation occurs, or a non-human animal model that suggests visual cues of reproductive hormone levels are important to sex differences in behavior.

I continue to have difficulty understanding the significance of reports that link an unknown process to stimuli that elicit brain activation associated with reward centers. Doesn't the significance depend at least somewhat on the pathway?