Poster #23 - Children’s Mental Rotation of Hands: Younger Children’s Mental Transformations Follow the Actual Movement

• In Event: 3-206 - Poster Session 13
  In Poster Session: PS 13 Section - Cognitive Processes

Integrative Statement

In previous studies different trajectories concerning the development of embodiment have been reported. Different theoretical approaches can be formulated to explain these findings. On the one hand, children might include motor resources in their cognitive processes increasingly over development which would lead to synergy effects. In this case, we would expect to find effects of embodiment in older children that are not detectable in younger ones. On the other hand, motor processes might become increasingly decoupled from cognitive processes enabling abstract thought. According to the latter approach, we would expect to find effects of embodiment in younger children that are not verifiable in older children.
Testing these approaches, we asked children aged 5 and 6 years to solve mental rotation tasks. Pictures of hands from a palmar perspective were used as stimuli. Children were presented with large pictures of either a left or a right hand. These pictures were displayed in different angles of rotation (0°, 90°, 180°, & 270° clockwise). In each trial, children were asked to decide which of two smaller comparison pictures matched the laterality of the large one (Fig. 1).
It is assumed that, in mental rotation tasks, the decision whether two stimuli are congruent, is based on a mental transformation of one of the stimuli along the shortest path to bring it into alignment with the other stimulus. Then it can be decided whether both stimuli are congruent. Usually, this results in a linear relation between reaction time (RT) and angular disparity. Comparing the RT patterns between both age groups, we found that such a linear trend was only present in the 6-year-olds. In contrast, 5-year-olds’ rotation paths seemed to follow an inward path instead of the shortest path. Actually, when beginning with one’s hands in the 0° position (as displayed in the comparison pictures in Fig. 1), due to physiological constraints, an outward rotation is blocked while an inward rotation is convenient. Concerning the right hand, this leads to a possible counter-clockwise rotation and for the left hand to a clockwise rotation. As can be seen in Figure 2a, the RT pattern suggests that 5-year-olds’ mental transformations of hands follow the physiological constraints exactly. It appears that, instead of an outward rotation of 90° (shortest path), the longer path in the opposite direction was chosen (270°), which takes longer than a rotation of 180°. In contrast to this, 6-year-olds’ mental transformations seemed to be influenced by the physiological constraints in a more subtle manner, as these constraints were reflected in a faster inward rotation of 90° in contrast to a slower outward rotation of 90° (Fig. 2b).
These findings suggest that younger children’s mental transformations are controlled more closely by physiological movement constraints than those of older children's ones. This can be interpreted as an indication of embodiment decreasing with development.

Authors

• Markus Krüger, University of Greifswald
  Presenting Author

• Horst Krist, University of Greifswald
  Non-Presenting Author