Proprioception, Body Reaching, and the Development of Mirror Self-Recognition

• In Event: The Role of Proprioception in the Development of Reaching and Knowledge About the Self

Abstract

Proprioception underlies knowledge about the position of our own bodies and self-movements, yet how it supports the development of body knowledge and, more broadly, self-knowledge is little understood. We examined how functional body knowledge, measured via self-reaching capabilities that rely on proprioception and tactile perception, developed across the first year. Next, we tested how this tactile reaching experience, along with additional contingent proprioceptive-visual experience, accelerated self-recognition. Taken together, these two studies provide insight into how a fundamental sense of body positioning may contribute to higher-order body abilities and self-knowledge.

In Study 1, a vibrotactile stimulus was placed at different locations on infants' faces (ears, mouth corners, chin, center forehead, lateral temples), one by one, and infants reaching responses to the target were recorded. Participants (n=24, age=2-11 months) were tested longitudinally approximately every two to three weeks. Infants improved at reaching to face targets across the first year (Wald x2 = 182.00, p < .001). Additionally, reaches became more direct across the first year (Wald x2 = 19.69, p < .001). These results suggest that during the first year infants become better at coordinating proprioceptive and tactile input centered on the face.

Next, a number of these infants (n=17) returned to the lab for monthly visits beginning at approximately 14 months, and continuing until up to 20 months. They were prompted to reach to the vibrotactile face target while looking in the mirror, prior to performing a rouge task. The goal was to test whether contingent proprioceptive, tactile, and visual information accelerated self-recognition. A control group was age-matched to the original group's first instance of self-recognition. For the experimental group 15 out of 17 infants indicated self-recognition on the rouge task (mean age of self-recognition=16.32 months). In contrast, for the age-matched control group, only 3 out of 15 infants indicated self-recognition (Fisher's exact test p <.001). The findings indicate that infants with tactile-proprioceptive-visual contingency experience recognized themselves earlier in a mirror than a control group without this experience.

Collectively, the results of these two studies indicate that functional body knowledge, which relies on proprioception and self-reaching, develops gradually across the first and second years. Furthermore, experience with contingent proprioceptive and visual information about the body accelerates mirror self-recognition. The findings suggest that earlier sensorimotor experiences centered on the body can promote later-developing and broader forms of self-knowledge.

Authors

• Lisa K. Chinn, University of Houston
  Presenting Author

• Katarina S. Patton, Tulane University
  Non-Presenting Author

• Claire Noonan, Tulane University
  Non-Presenting Author

• Jeffrey J Lockman, Tulane University
  Non-Presenting Author