Abstract # 2359 Event # 133:

Scheduled for Saturday, June 21, 2008 09:15 AM-09:25 AM: Session 14 (Meeting Room 1GHI) Oral Presentation


INTERINDIVIDUAL DIFFERENCES IN NEONATAL IMITATION AND THE DEVELOPMENT OF ACTION CHAINS IN RHESUS MACAQUES

P. Ferrari1,2, A. Paukner2, A. Ruggiero2, L. Darcey2, S. Unbehagen2 and S. J. Suomi2
1Dipartimento di Biologia Evolutiva e Funzionale, Università di Parma, via Usberti 11A, 43100, Parma, Italy, Parma, Emilia Romagna 43100, Italy, 2Laboratory of Comparative Ethology, NICHD, NIH, Bethesda, MD 20892-7971, USA
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     We recently reported newborn imitation in macaques. Interindividual variability in the display of this behavior may be related to differences in specific sensorimotor processes at birth that can lead to differential expressions of neurobehavioral patterns of development. We evaluated the differential imitative neonatal response of newborn macaques (Macaca mulatta) in the first week of life (3 test sessions) in relation to the development of sensory, motor and cognitive skills in the first month of life. Nursery-reared infant macaques were tested once a week by means of neonatal neurobehavioral assessment scales. Results show that newborns that imitate facial gestures at birth (n=21) display more developed skills in goal-directed movements (reaching-grasping and fine hand motor control) than non-imitators [n=15; ANOVA, a=0.01]. Other neurobehavioral parameters and weight development did not differ between the two groups. Our data indicate that a basic chain organization for reaching and grasping is present in newborn macaques. Very likely the difference between imitators and non imitators in the control of goal-directed movements might reflect the differential maturation of motor chains in the parietal and motor cortex. We hypothesize that part of these cortical areas are in common with those of the mirror neuron system, a mechanism matching action execution with action observation and that is involved in adult human imitation. This work is supported by the intramural research program of the NIH