Influence of swaddling on tactile manual learning in preterm infants

Background and aim: Swaddling is a well-known technique in developmental care programs as there is some evidence that swaddling is an appropriate stress-reducing method for preterm infants in the NICU. However, no experimental study has investigated the influence of swaddling in a learning context. This study aimed to assess the impact of swaddling on tactile manual abilities in preterm infants. Methods: Two phases were introduced for all infants: habituation (successive presentation of the same object, prism or cylinder in the left hand), followed by discrimination (presentation of a new-shaped object). The infants were assigned to one of the two conditions (swaddled; non-swaddled). Results: Forty preterm infants were included (between 28 and 35 weeks' postconceptional age). First, swaddled and non-swaddled infants exhibited similar tactile habituation abilities. However, all infants needed more time and more trials to habituate to the cylinder than to the prism. Second, they all exhibited an effective discrimination, but the importance of the increase in holding time for the new-shaped object varied according to the habituated-shape and the condition. Moreover, stress intensity was higher in non-swaddled infants during tactile exploration. Finally, infants with greater previous swaddling experience during the week preceding the test took more time and more trials to habituate to the object, regardless of the condition. Conclusion: Swaddling preterm infants during sensory learning did not influence the tactile memorization process but would improve the use of their attentional resources. Swaddling seems to provide favorable conditions for sensory learning by improving attention to tactile stimuli. Clinical Trial Registration: This trial, EMMASENS, has been registered at www.clinicaltrials.gov (identifier NCT04315428).