How was goal directed imitation operationalised?

1. Goal-Directed Imitation: State or Trait? Elena Sakkalou, Katherine Ellis, Nia Fowler, Elma Hilbrink & Merideth Gattis Cardiff University • Introduction • Debates about the mechanisms underlying imitation focus on comparisons of group means across experimental conditions. Such comparisons allow inferences about whether imitation was goal-directed in one condition versus another, but do not allow inferences about whether goal-directed imitation varies consistently between individuals (Bekkering, Wohlschläger, & Gattis 2000; Carpenter, Call, & Tomasello, 2005) • Data at the individual level suggest that there is individual variability in imitative behaviour, but little else is known. • The aim of this project is to establish whether variability in imitation reflects meaningful individual differences, and therefore might be used to test hypotheses about the mechanisms. • We compared infant performance on two experimental measures of goal-directed imitation to examine whether goal-directed imitation is a trait with inter-individual variability. We tested 37 infants on two measures, one at 13 and one at 14 months. 1 0.8 0.6 0.4 0.2 0 Mean proportion Ohi-Nato Task No Action One Action Two Actions There was a relationship between the performance of infants on the two end locations in the Mouse-House Task and the proportion of intentional actions performed in the Ohi-Nato Task, r = .34 (p =.04). Ohi-Nato Task • Mouse-House Task • Age: Goal-directed imitation measured at 13 months • How was goal-directed imitation operationalised? • Reproducing the experimenter’s movement of a toy to a specific location. • How was a score computed? • A proportion was calculated by dividing the number of goal-directed actions performed by infants by the possible number of goal-directed actions. • Discussion • Our results are consistent with previous studies reporting group means: infants interpret adults’ actions in terms of goals, and early in the second year, reproduce those goals. • Performance on the two imitation tasks was positively correlated, supporting the hypothesis that goal-directed imitation is a trait with inter-individual variability. • Future studies will build on the consistencies in imitation to compare hypotheses about the mechanisms underlying imitative behaviours. Age: Goal-directed imitation measured at 14 months. • How was goal directed imitation operationalised? • Reproducing the action that had been accompanied by the purposeful tone of voice. • How was a score computed? • A proportion was calculated by dividing the number of intentional actions performed by infants by the total number of intentional and accidental actions performed by infants. 6 5 4 3 2 1 0 References Bekkering, H., Wohlschläger, A., & Gattis, M. (2000).Quarterly Journal of Experimental Psychology, 53A, 153–164. Carpenter, M., Call, J., & Tomasello, M. (2005). Developmental Science, 8, F13- F20. Acknowledgements We would like to thank the EPS for the Grindley Grant awarded to Elena Sakkalou and the Leverhulme Trust for funding this research. Frequency Frequency 0 .5 1