Effects of early adverse experiences on behavioural lateralisation in rhesus monkeys (Macaca mulatta)

Abstract

In the past 15 to 20 years, evidence of population-level handedness in non-human primates has emerged from a plethora of studies, although considerable inconsistency is also apparent. The study reported here examined two factors that may contribute to the expression of hand preference: early rearing history and sex differences. Handedness was assessed in rhesus monkeys (Macaca mulatta) using a task that measures coordinated bimanual actions and is referred to as the TUBE task. Nursery-reared monkeys demonstrated greater left-hand bias in the TUBE task when compared to their mother-reared counterparts. Females showed greater right-hand preference and stronger bias on the TUBE task compared to males. These results provide evidence that early rearing experiences significantly influence the development of lateralisation in nonhuman primates.

Acknowledgements

This work was supported by NIAAA grants AA-13995 and AA-11997 to AJB, NS-42867 and HD-56232 to WDH, the Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and Alcoholism, and the Laboratory of Comparative Ethology (LCE), National Institute on Child Health and Human Development. We are grateful for the contributions and support of Drs Peter J. Pierre, J. Dee Higley, Maribeth Champoux, and to Sue Higley, Heather Rupp, Cori Garrett-Goodyear, Kristina Kaiss, and the neonatal nursery staff at LCE NICHD.