Abstract # 75:

Scheduled for Thursday, August 18, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation

Picture It: The Use of Multi-Dimensional Scaling Techniques in Understanding Mother/Infant Rhesus Monkey (Macaca mulatta) Behavior

K. McCormack1,2, M. M. Sanchez1,2, D. Maestripieri2,3 and M. Bardi4
1Emory University, Department of Psychiatry and Behavioral Sciences, Atlanta, GA, 2Yerkes National Primate Research Center, 3Institute for Mind and Biology, University of Chicago, 4Department of Comparative Medicine, Southwest Foundation Biomedical Research, San Antonio, TX
     This study examined the underlying structures of behavior among abusive and non-abusive rhesus mother-infant pairs. Multidimensional scaling (MDS) is a data reduction technique that uncovers the similarities among subjects and their behaviors. MDS can provide a map of the overall maternal styles of monkey mothers, as well as a global representation of the behaviors that characterize infants. Ten abusive and ten non-abusive mother-infant pairs were observed weekly, from months 1-6, at the Yerkes Primate Center. All mother-infant interactions were recorded, as well as infant behaviors alone, and with others. These behaviors were subjected to nonmetric unfolding MDS analyses, in two time blocks: months 1-3 and 4-6. Maternal MDS analyses revealed two primary clusters of care: rejecting and protective/restraining. Ninety percent of the abusive mothers fell within the rejecting cluster, while ninety percent of the control mothers were protective. Infant MDS analyses revealed two primary clusters of behavior: exploratory and dependent. The majority of the abused infants fell into the dependent cluster, while the majority of the non-abused were exploratory. For both the maternal and infant analyses, findings were most robust during months 1-3 (RSQ = 0.82 and 0.88 respectively), which is when abuse was frequent, compared to months 4-6 (RSQ = 0.70 and 0.64 respectively). These results suggest that there are differences in maternal care among abusive and non-abusive mothers, and that these differences impact the behavioral repertoire of the infants. Support: NIMH grants MH01005 (MMS), MH62577 (DM), GM00680 (KM), & RR-00165.