Variation in oxytocin receptor density in the nucleus accumbens has differential effects on affiliative behaviors in monogamous and polygamous voles.
Level 5 - mechanism / opinion, no new human data
Animal experimental study using viral vector gene transfer in rodents.
PubMed 19193878 · doi:10.1523/JNEUROSCI.5039-08.2009
What was done
Researchers delivered adeno-associated viral vectors to overexpress oxytocin receptors in the nucleus accumbens of adult female monogamous prairie voles and nonmonogamous meadow voles. They evaluated the effects of accumbal oxytocin receptor upregulation on partner preference formation following cohabitation with a male and on alloparental care behavior.
What was found
No quantitative values, effect sizes, or p-values are reported in the abstract. Qualitatively, accumbal oxytocin receptor overexpression accelerated partner preference formation after cohabitation in female prairie voles without enhancing alloparental behavior. In contrast, introducing oxytocin receptors into the nucleus accumbens failed to facilitate partner preference in nonmonogamous meadow voles.
Why it matters
This study provides direct experimental evidence linking variations in accumbal oxytocin receptor density to differences in attachment behavior within a monogamous species, while demonstrating that receptor expression in this single brain region is not sufficient to induce pair bonding in a nonmonogamous species.
Limits
The study was conducted entirely in rodent models (voles), limiting direct human generalizability. The abstract reports no sample sizes, numerical outcomes, or variability measures. The experiment was confined to adult females and tested a single brain region.
Cited by
- contradicts Genetically modifying mice or non-monogamous animals to express oxytocin receptors causes them to become more socially active.