Training of 7-month-old infants' manual object exploration skills: Effects of active and observational experience.

In the present study, a fine motor training was developed and evaluated in which infants were trained to manually explore objects in an advanced manner. Fifty 7-month-old infants were randomly assigned to three different training conditions: (1) to an active manual exploration training, in which they learned to explore objects efficiently, (2) to an observational manual exploration training, in which they observed how an adult performed sophisticated actions on objects, or (3) to a control group receiving no training. The results impressively indicate that infants with a low level of object exploration skill prior to the training showed the most training effects as compared to infants with proficient object exploratory actions. Interestingly, this differential training effect was true for both the active and observational training, highlighting the role of social learning in infancy. Importantly, our study shows for the first time the impact of normal individual variation in infants' manual object exploration skills on the effects of a fine motor training.