Infants' and toddlers' remembering and forgetting of a stressful medical procedure.

Objective: To examine whether a distressing medical procedure leaves lasting impressions in young children's memories.

Methods: Children 12- to 78-weeks old (N = 172) received inhalation treatment through a face mask or underwent other interventions at a pediatric emergency department. They were randomized to be presented with neutral cues and cues from the inhalation 1 week or 6 months after the target event. Children's reactions at cue presentation were scored from videotapes.

Results: Across the age span tested, children treated with inhalation showed higher distress than controls when presented with cues from inhalation 1 week, but not 6 months after target treatment.

Conclusions: Stress during medical procedures in preverbal children may develop as a result of prior experience of such procedures. These memories typically seem to fade within 6 months.