Prior sleep timing and visual recognition of emotional faces in 6-month-old infants

• Published in: Infant behavior & development Vol. 65; p. 101655
• Main Authors: Seehagen, Sabine, Herbert, Jane S., Zmyj, Norbert
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2021
• Subjects: Adult; Anger; Emotions; Face processing; Facial Expression; Facial Recognition; Humans; Infant; Infants; Nap; Prior sleep; Recognition, Psychology; Sleep; Visual recognition; Prior sleep; Infants; Nap; Face processing; Emotions; Visual recognition
• ISSN: 0163-6383; 1879-0453; 1934-8800
• DOI: 10.1016/j.infbeh.2021.101655

•We tested 6-month-olds’ face recognition in relation to prior sleep timing.•Recognition of faces showing negative emotions was enhanced after long wakefulness.•Infants’ emotional information processing might vary during their sleep-wake cycle. Face recognition is an important mnemonic ability for infants when navigating the social world. While age-related changes in face processing abilities are relatively well documented, less is known about short-term intra-individual fluctuations in this ability. Given that sleep deprivation in adults leads to impairments in information processing, we assessed the role of prior sleep on 6-month-old infants’ (N = 17) visual recognition of faces showing three emotional expressions (neutral, sad, angry). Visual recognition was inferred by assessing novelty preferences for unfamiliar relative to familiarized faces in a visual recognition memory paradigm. In a within-subject design, infants participated once after they had recently woken up from a nap (nap condition) and once after they had been awake for an extended period of time (awake condition). Infants failed to show visual recognition for the neutral faces in either condition. Infants showed recognition for the sad and angry faces when tested in the awake condition, but not in the nap condition. This suggests that timing of prior sleep shapes how effectively infants process emotionally relevant information in their environment.