Differential Attentional Responding by Planned and Emergency Caesarean-Section Versus Vaginally Delivered Infants and Adults

Search asymmetry occurs when feature-present targets are detected more easily than feature-absent targets, resulting in an efficient search (i.e. flat RT - set size function) for feature- present targets, but an inefficient search (i.e. increasing RT set size function) for feature-absent targets. Both 3-month-old infants and adults have been found to exhibit a search asymmetry when assessed with saccade latencies (Adler & Gallego, 2014). Additionally, caesarean-section delivered infants exhibit slower attention and saccadic latencies than those born vaginally (Adler & Wong-Kee-You, 2015). This study is designed to determine the relative effects of different birth experiences on attention and search asymmetry performance and whether differences persist in adulthood. Two different visual circular arrays were presented: feature-present target among feature-absent distractors (R among Ps) or feature-absent target among feature-present distractors (P among Rs) with array set sizes of 1, 3, 5, 8. Results indicated that infants and adults saccadic latencies were unaffected by set size in feature-present arrays, suggesting an efficient search. Both caesarean-section born infants and adults had slower saccadic latencies when compared to the vaginal groups. Interestingly, infants born via planned caesarean-section were slower when compared to an emergency caesarean-section. There were no differences in saccadic latencies, however, between emergency and planned caesarean-section adults, suggesting that any difference due to planned vs emergency caesarean-sections does not persist into adulthood. For feature absent targets, both infants and adults exhibited increasing saccadic latencies with set size, suggesting an inefficient search. These findings suggest that any caesarean-section birth influences bottom-up attention and requires greater reliance on top-down processing even into adulthood. Thus, the development of attentional mechanisms can be influenced by early birth experiences that also impact adulthood.