Abstract
Previous research with infants has indicated that they are fully capable of performing a feature search in a manner nearly identical to adults (Adler & Orprecio, 2006; Fuda & Adler, 2012), but are developmentally immature in localizing a target in a conjunction search (Fuda & Adler, 2012). This might be accounted for by feature searches relying mainly on bottom-up attentional resources to localize a target, whereas conjunction searches would require top-down attentional resources in addition to bottom-up resources (Wolfe, 1994). Since infants have been shown to perform a feature search but not a conjunction search in a similar manner to that performed by adults, the current study attempted to investigate whether this might be due to bottom-up attentional mechanisms developing before top-down mechanisms. To this end, 3-month-old infants were presented with two types of cues prior to a conjunction search array that provided them with either bottom-up or top-down information that might facilitate their conjunction search. The bottom-up cue consisted of four rectangular frames indicating where the possible location of the target would be, whereas the top-down cue consisted of the brief presentation in the visual center of what the target would be. Infants’ saccade latencies were recorded for three different set sizes of (5, 8, & 10) when the target was either present or absent. Results revealed that the top-down cue, but not the bottom-up cue, facilitated infants’ exhibition of a more adult-like conjunction search function where latencies increased with increasing set sizes. These findings suggest young infants’ top-down processing mechanisms are developmentally immature relative to their bottom-up mechanisms, at least in visual search tasks. Furthermore, this study represents the first time these attentional mechanisms have been assessed in infancy and may serve as a window into understanding not only typical attentional development but also atypical development with attentional deficits.
Meeting abstract presented at VSS 2013