Intergenerational transmission of maternal behavior in rhesus macaques and its underlying mechanisms

Thirteen group-living rhesus macaque females that were crossfostered shortly after birth were followed longitudinally until they gave birth for the first time. Their maternal behavior was compared to the behavior of both their foster and their biological mothers, and analyzed in relation to the cerebrospinal fluid (CSF) concentrations of serotonin, dopamine, and norepinephrine metabolites (5-HIAA, HVA, and MHPG) measured in their second year of life. Crossfostered females were similar to their foster mothers in their rates of maternal rejection and grooming, whereas their contact-making behavior was more similar to that of their biological mothers. Crossfostered females with lower CSF concentrations of 5-HIAA exhibited higher rates of maternal rejection than females with higher CSF 5-HIAA. In a related article (Maestripieri et al., 2006), we reported that rhesus infants reared by highly rejecting mothers had lower CSF 5-HIAA in their first 3 years of life. Taken together, these findings suggest that early social experience and experience-related long-term changes in serotonergic function may play a role in the intergenerational transmission of maternal rejection from mothers to daughters.     

Developmental craniofacial anthropometry: Assessment of race effects

Differences in craniofacial anatomy among racial groups have been documented in a variety of structures, but the oral and maxillofacial regions have been shown to be a particularly defining region of variability between different racial/ethnic groups. Such comparisons are informative, but they neither address developmental changes of the craniofacial anatomy nor do they assess or take into account the natural variability within individual races that may account for similar reported, across‐group variations. The purpose of this report was to compare—using medical imaging studies—the growth trend of select race‐sensitive craniofacial variables in the oral and pharyngeal regions when all races [White, Asian, Black, and Hispanic (AR)] are included versus only a single race category [White (WR)]. Race effect was tested by comparing sex‐specific growth fits (fourth degree polynomial model) for AR versus WR data. Findings indicate that the inclusion of all races versus a single race did not significantly alter the growth model fits. Thus, the inclusion of all races permits the advancement of general growth models; however, methodologically, it is best to treat the race variable as a covariate in all future analysis to test for both potential all race effects or individual race effects, on general growth models. Clin. Anat. 22:800–808, 2009. © 2009 Wiley‐Liss, Inc.