Social cues at encoding affect memory in 4-month-old infants

Abstract

Available evidence suggests that infants use adults' social cues for learning by the second half of the first year of life. However, little is known about the short-term or long-term effects of joint attention interactions on learning and memory in younger infants. In the present study, 4-month-old infants were familiarized with visually presented objects in either of two conditions that differed in the degree of joint attention (high vs. low). Brain activity in response to familiar and novel objects was assessed immediately after the familiarization phase (immediate recognition), and following a 1-week delay (delayed recognition). The latency of the Nc component differentiated between recognition of old versus new objects. Pb amplitude and latency were affected by joint attention in delayed recognition. Moreover, the frequency of infant gaze to the experimenter during familiarization differed between the two experimental groups and modulated the Pb response. Results show that joint attention affects the mechanisms of long-term retention in 4-month-old infants. We conclude that joint attention helps children at this young age to recognize the relevance of learned items.

Keywords:

• Event-related potentials
• Long-term memory
• Joint attention
• Infancy
• Visual recognition

Acknowledgments

This work was supported by the Ernst Rudolf Schloessmann Foundation. The authors wish to thank the members of the BabyLab at the Max Planck Institute for Human Development, and the parents and infants who participated in this study. We are grateful to Julia Delius for improving the English.

Notes

¹ Note that Session × Group also proved to be reliable on Pb latency in control analyses in posterior electrodes, F(1, 28) =  5.12, p =  .032, η² =  .16 (see Figure 2).

² Note that frequency and proportional duration of infant gaze to the experimenter were highly correlated (r =  .89, p < .001).