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In the flanker paradigm, participants identify a target letter while attempting to ignore an irrelevant flanker. When the identity of this flanker mismatches the target, target identification is slowed (called the flanker compatibility effect). Interestingly, reducing the array set size greatly increases flanker compatibility effects. This finding inspired 2 prominent explanations: perceptual load (mandatory capacity spillover) and dilution (visual interference). However, an alternative explanation, based on early selection theory and attention capture research, can also explain the data pattern. According to this "slippage" account, observers sometimes accidentally allocate spatial attention to the flanker (see Lachter, Forster, & Ruthruff, 2004), especially when the flanker has the property used to find the target (cf. contingent capture). In Experiments 1 through 4, deterring slippage to the flanker nearly eliminated flanker compatibility effects, even at the low set size. In Experiment 5, promoting slippage to the flanker dramatically enhanced compatibility effects, even at the high set size. Thus, slippage strongly modulates flanker effects and can, by itself, readily explain the impact of set size. The perceptual load and dilution accounts are, at best, incomplete, and, at worst, not needed.

Theeuwes (Psychonomic Bulletin & Review 11:65-70, 2004) proposed that stimulus-driven capture occurs primarily for salient stimuli that fall within the observer's attentional window, such as when performing a parallel search. This proposal, which is supported by some studies, can explain many seemingly discrepant results in the literature. The present study tested this proposal using a modified precuing paradigm. Search mode was manipulated via target-distractor similarity in color space. In the parallel search condition, the orange target "popped out" from a set of distantly colored distractors (blue and green). In the serial search condition, the orange target was more difficult to find amongst a set of similarly colored distractors (yellow and red). In Experiments 1 and 2, cue validity effects for irrelevant-color singleton cues were greater under parallel than under serial search, at least partially replicating previous studies favoring the attentional-window account (e.g., Belopolsky, Zwaan, Theeuwes, & Kramer, Psychonomic Bulletin & Review 14:934-938, 2007). We found the opposite pattern, however, for capture by abrupt onsets (Experiments 3 and 4), in which case capture effects were actually greater under serial search. In sum, parallel search appears to facilitate capture by color singletons, yet to inhibit capture by abrupt onsets.Keywords Attentional capture . Visual search . Spatial attention Sometimes, task-irrelevant information draws our attention. While driving, for example, a bright billboard advertisement might draw attention, seemingly against our will. Yet at other times, very salient information fails to capture our attention: A waving pedestrian (or, classically, a waving gorilla) may go unnoticed (Simons & Chabris, 1999). Indeed, one might wonder how a person distracted by every salient stimulus (e.g., flashing police beacons, brake lights, blinking crosswalk signs, or neon traffic cones) could possibly survive a single trip to the grocery store. These simple observations raise the question of how involuntary shifts of attention are guided. Can certain "super" stimuli capture our attention at any moment (bottom up)? Or are these shifts involuntary and yet, counterintuitively, driven by what we are looking for (top down)?Research on attention capture has made great strides in identifying laboratory scenarios in which salient stimuli do and do not capture attention. However, opinions are still sharply divided about how to reconcile the puzzling empirical discrepancies from different paradigms and different types of salient stimuli. Theeuwes (2004Theeuwes ( , 2010 has proposed one promising reconciliation, in which stimulus-driven capture occurs only when objects are searched in parallel. This claim, if correct, would have important theoretical implications, as well as important practical implications for identifying realworld scenarios that leave an operator vulnerable to irrelevant capture. Although several findings have been suggestive (e.g

BackgroundGraft shrinkage or radial extrusion is a reported complication after meniscus allograft transplantation (MAT). Whether shrinkage or extrusion progress after surgery and whether they are associated with the clinical outcome of MAT remain debatable. In this study, graft shrinkage and extrusion were measured in the coronal and sagittal planes using serial postoperative magnetic resonance imaging (MRI). The purpose of this study was to evaluate if graft shrinkage or extrusion is correlated to the clinical outcome of MAT.MethodsMRIs acquired at 3 and 12 months postoperatively in 30 patients (21 men and 9 women) who underwent MAT (6 medial and 24 lateral menisci) from 2010 to 2016 were analyzed. Two orthopedic surgeons and two musculoskeletal specialized radiologists each performed the MRI measurements. Allograft shrinkage was measured by the width and thickness of the graft at the coronal and sagittal planes. To determine the graft extrusion, distances between the proximal tibia cartilage margin and the extruded graft margin were measured in both coronal (either lateral or medial) and sagittal (both anterior and posterior) plane and relative percentage of extrusion (RPE) were calculated. Subjective International Knee Documentation Committee (IKDC) scores at 12 months were evaluated as a clinical outcome measurement, and correlations between shrinkage or extrusion of allograft and IKDC score were analyzed.ResultsIn the coronal plane, radial RPE averaged 43.6% at postoperative 3 months, but there was no significant progression of extrusion at 12 months (average 42.0%) (P = 0.728). In the sagittal plane, there were no significant progressions of anterior and posterior RPE (P = 0.487 and 0.166, respectively) between postoperative 3 and 12 months. Shrinkage was calculated by multiplying the width and height of the three sections and summing these values. There was no significant progression of shrinkage between postoperative 3 and 12 months (P = 0.150). RPE in the radial (R = 0.147, P = 0.525), anterior (R = 0.249, P = 0.264), and posterior (R = 0.230, P = 0.315) directions and shrinkage (R = 0.176, P = 0.435) were not correlated to IKDC score at postoperative 12 months.ConclusionsIn the coronal and sagittal planes, extrusion and shrinkage did not progress from 3 months to 1 year. Extrusion and shrinkage had no correlation with early clinical outcomes. This finding suggests that graft extrusion or shrinkage may be not a great concern especially in early postoperative period of MAT, and multiple, serial MRI may be not necessary.