Attentional Switching in Infants as a Function of Birth Experience: An Eye Movement Study

Studies have shown that visuospatial attentional performance in a Posner-like attentional cueing task by 3-month-old and 6-month-old infants, and adults, is influenced by birth experience; that is, whether they were delivered via C-section or vaginally. In particular, these findings suggested that C-section birth produces aberrant bottom-up attentional mechanisms. What is not known is whether this birth experience effect produces deficits in selective attention that are specific to the mechanisms engaged by peripheral cueing or translates to other attentional phenomena. To this end, in this study, 6-month-old infants born either vaginally or via C-section participated in an expectation cueing task that used central cueing and their anticipatory and reactive saccades were measured. In the first condition, infants saw centrally presented cues, one of the cues predicted a target to the left and the other predicted a target to the right. Halfway through, the cue that predicted a target to the left side, for example, switched and now predicted a target on the right side and vice versa. In the second condition, which served as a control, the cues did not predict target location during the first half of trials. In the second half, the cues now reliably predicted the target location. Results have indicated that 6-month-old infants, irrespective of birth experience, form expectations for the cue-target location relation and exhibit anticipatory saccades when that relation is predictable. When the cue-target location relation is switched, infants’ anticipatory saccades decreased irrespective of birth experience. Latencies of reactive saccade saccades, however, increased post-switch for infants born by C-section but not for those born vaginally. These findings suggest that C-section birth impacts selective attention mechanisms irrespective of the task. More importantly, that the effect of C-section birth is reflected in reactive saccades and not anticipatory saccades is consistent an aberrant bottom-up attentional mechanism.