Physical separation from the mate diminishes male's attentiveness towards other females: a study in monogamous prairie voles Microtus ochrogaster.

We tested whether continuous cohabitation in monogamous voles affects the mated male's attentiveness to his breeding partner versus another female. Each male was housed in a 3-chamber apparatus with a Focal female (FF) and a Control female (CF) for 13 days then placed in a T-maze to assess his attentiveness to and memory of those females. The Distal male remained physically separated from both females, but received their distal cues. The Separate male cohabited with the FF for 3 days then remained physically separated from both females. The Disrupt male's continuous cohabitation with the FF was disrupted by having him physically separated from her after 10 days and placed with the CF for the last 3 days. The Continuous male cohabited continuously with the FF for 13 days. With females in the T-maze, the Separate and Disrupt males spent more time near the FF's box and the Disrupt males spent more time manipulating the FF's box than the CF's box. The Separate males groomed themselves more when near the FF's box than the CF's box. The Distal and Continuous males' attentiveness to the two females did not differ. Results suggest that physical distance from the partner may reduce male's attentiveness toward other potential mates. Prairie voles might be similar to socially monogamous primates in using tactile cues as a signal for maintaining their social bonds.

Mating increases male's interest in other females: a cognitive study in socially monogamous prairie voles (Microtus ochrogaster).

To determine whether socio-sexual interactions with females influence the male prairie vole's cognitive processing, three groups of males were simultaneously exposed to sensory stimuli of a control and a focal female then tested for their behavioral and neuronal responsiveness to the female cues. From the control female, all males received distal cues. From the focal female, the Unmated males received distal cues, the Unmated-Contact males received all cues but did not mate with her, and the Mated-Contact males received all cues and mated with her. Males were tested for their attentiveness to enclosures holding each female and for their memory of the females' previous location. Males' brains were then examined to localize activated regions following exposure to the odor of familiar versus unfamiliar focal females. The Mated-Contact males spent more time in the cage of the control female attending to her enclosure than in the cage of the focal female. Exposure to odors of unfamiliar focal females activated the cingulate cortex of Unmated-Contact males. There was a negative correlation between the level of neuronal activation in the retrosplenial cortex of males that were exposed to the odors of a familiar focal female and their attentiveness to the enclosure of the control female. The data suggest that the effect of socio-sexual interactions with a female on males' cognition depends on the type of sensory signals males receive from females and how individual males perceive those signals.