Perceived reachability for self and for others by 3- to 5-year-old children and adults

Ability to perceive the distance at which an object is within reach was assessed in 3-, 4-, and 5-year-old children and adults. In different situations, subjects had to judge whether an object placed in the vertical or horizontal plane was reachable for themselves or for someone else (the experimenter). Adults as well as children differentiated between the limits of their own prehensile space and those of another person. At all ages, children tend to attribute systematically more reachability to the adult experimenter. Furthermore, both children and adults systematically underestimate reachability for others in a horizontal presentation of the object. For all age groups, judgments of reachability for self are bodily scaled and based on perceived degrees of behavioral freedom for self and for others. From 3 years of age, children are shown to resemble adults in their ability to perceive what objects afford for action, either for self or for others. These results are interpreted as further evidence of early allocentrism (i.e., spatial decentration and perspective taking) in the context of a practical task.