BODY PROCESSING AND ATTENTIONAL PATTERNS IN INFANCY

Bodies provide important social information, and adults benefit from this information by recognizing and responding appropriately to bodies. Body recognition is enabled by the fact that human bodies are defined by parts, such as the limbs, torso, and head, arranged in a particular configuration. To understand the development of social cognition, it is important to analyze and document how infants come to recognize bodies. Infants are sensitive to distortions to the global configurations of bodies by 3.5 months of age, suggesting an early onset of body knowledge. It was unclear, however, whether such sensitivity indicates knowledge of the location of specific body parts or solely reflects sensitivity to the overall gestalt or outline of bodies. The current study addressed this by examining whether infants attend to specific locations in which parts of the body have been reorganized. Results of Experiments 1 and 2 show that 5-month-olds, but not 3.5-month-olds, are sensitive to the location of specific body parts, as demonstrated by a difference in allocation of attention to the body joint areas that were normal (e.g., where the arm connects to the shoulder) versus ones that were reorganized. Furthermore, to examine whether this kind of processing is driven by information from the face/head, in Experiment 3 I tested infants on images in which the face/head was removed. Infants no longer exhibited differential scanning of normal versus reorganized bodies. To further assess whether infants were responding to critical information provided by the face/head or whether their processing was disrupted solely because the headless images were incomplete bodies, Experiment 4 examined infants’ performance on body images missing limbs. Once again, infants failed to exhibit differential scanning of typical versus reorganized bodies. Together, these results suggest that 5-month-olds are sensitive to the location of body parts. However, the presence of the face/head (Experiment 3) and limbs (Experiment 4) are necessary for 5-month-olds to exhibit differential scanning of reorganized versus intact body images. Overall, by 5 months of age, infants are sensitive to precise locations of body parts, and thus demonstrate a rather sophisticated level of knowledge about the structure of the human body. The role that the face/head and limbs play in body structure knowledge development is still unclear, and future studies need to address this question

Development of Body Emotion Perception in Infancy: From Discrimination to Recognition

Research suggests that infants progress from discrimination to recognition of emotions in faces during the first half year of life. It is unknown whether the perception of emotions from bodies develops in a similar manner. In the current study, when presented with happy and angry body videos and voices, 5-month-olds looked longer at the matching video when they were presented upright but not when they were inverted. In contrast, 3.5-month-olds failed to match even with upright videos. Thus, 5-month-olds but not 3.5-month-olds exhibited evidence of recognition of emotions from bodies by demonstrating intermodal matching. In a subsequent experiment, younger infants did discriminate between body emotion videos but failed to exhibit an inversion effect, suggesting that discrimination may be based on low-level stimulus features. These results document a developmental change from discrimination based on non-emotional information at 3.5 months to recognition of body emotions at 5 months. This pattern of development is similar to face emotion knowledge development and suggests that both the face and body emotion perception systems develop rapidly during the first half year of life