Saccadic repulsion in pop-out search: How a target's dodgy history can push the eyes away from it

Abstract

Previous studies have shown that even in the context of fairly easy selection tasks, as is the case in a pop-out task, selection of the pop-out stimulus can be sped up (in terms of eye movements) when the target-defining feature repeats across trials. Here, we show that selection of a pop-out target can actually be delayed (in terms of saccadic latencies) and made less accurate (in terms of saccade accuracy) when the target-defining feature has recently been associated with distractor status. This effect was observed even though participants' task was to fixate color oddballs (when present) and simply press a button when their eyes reached the target to advance to the next trial. Importantly, the inter-trial effect was also observed in response time (time to advance to the next trial). In contrast, this response time effect was completely eliminated in a second experiment when eye movements were eliminated from the task. That is, when participants still had to press a button to advance to the next trial when an oddball target was present in the display (an oddball detection task experiment). This pattern of results closely links the "need for selection" in a task to the presence of an inter-trial bias of attention (and eye movements) in pop-out search.

Exploring the contributions of spatial and non-spatial working memory to priming of pop-out

“…Inferior temporal areas are known to process object-related information such as color and shape (see, e.g., Grill-Spector, Kushnir, Edelman, Itzchak, & Malach, 1998;Grill-Spector & Malach, 2001), whereas the fronto-parietal network is believed to control spatial attention (Kastner & Ungerleider, 2001;LaBar, Gitelman, Parrish, & Mesulam, 1999). Finally, eye movement data on three-item oddball displays like the ones used here also showed that participants were actually relatively bad at fixating the target when the target on the current trial differed in color identity from that on the previous trial (Becker, 2008;Caddigan & Lleras, 2010). That is, if targets in these displays were really popping out, one would have expected exceedingly good (perhaps perfect) saccades to the target on every trial, yet that was not the case.…”

“…If this is the same mechanism responsible for PoP, it would suggest that spatial VWM is directly involved in this identity-based refoveating mechanism. One inconsistency, however, is that saccadic RTs in three-item oddball search displays are several hundred milliseconds slower (upward of 300 ms; see Caddigan & Lleras, 2010) than those in the gaze correction experiments reported by Hollingworth and colleagues (around 140 ms). Thus, the temporal dynamics for fast gaze correction do not seem to support target foveation in traditional PoP displays.…”

Trial History Effects in the Ventral Attentional Network

“…They are in line with behavioral work showing that most (if not all) of the DPE is exerted as a difficulty to orient to the target, when the target belongs to the category of items in the preceding target-absent trial. This has been shown using manual responses ), a saccadic selection task (Caddigan & Lleras, 2010), RSVP task ) and by modeling saccade performance in a pop-out task as an attentional decision making task (Tseng et al, 2014). The current results are therefore consistent with the larger literature in which the DPE is better understood as an attentional than a perceptual bias.…”

“…Ventral Stream ROI analysis; PPA: As mentioned above, the DPE reflects a compromise in the ability of an attended item to drive behavior if that item has been rejected on a previous trial; prior suppression of current distractor material does not benefit performance (Caddigan & Lleras, 2010;). Preview effects should therefore emerge in the regions active in processing target material.…”

“…Despite its name, the DPE in fact derives from the cost of orienting towards a target item that has the same features as recent non-targets rather than a benefit of orienting away from distractor features that have recently been ignored (Caddigan & Lleras, 2010;). Both phenomena illustrate the tendency of biases within the attentional system to persist across trials, even under circumstances in which attentional selection should be effortless and automatic (popout search).…”