No templates for rejection: a failure to configure attention to ignore task-irrelevant features

ABSTRACT

Knowing the colour of an upcoming target allows one to bias attention towards objects of that colour. It is far less clear whether knowing the colour of an up-coming distractor can allow one to suppress attention to items of that colour. Arita, Carlisle, and Woodman (2012) suggest that people can create a template for rejection. However, the method used in Arita et al. may have allowed people to adopt a strategy of internally generating a positive cue for the target colour or target hemifield. Here we use a method very similar to theirs, but manipulate the display layouts and the number of un-cued colours in ways that should thwart such strategies. Across three experiments, we find a negative cuing benefit only in a very special circumstance that encourages a strategic shift to internally generating a positive cue (the same circumstance used by Arita et al.). We conclude that people are unable to use a negative feature-cue on a trial-by-trial basis to suppress attention to upcoming distractors, and attribute the finding in Arita et al. to a strategic shift rather than a template for rejection.     

Mind-reading without the scanner: Behavioural decoding of working memory content

ABSTRACT

Sophisticated machine learning algorithms have been successfully applied to functional neuroimaging data in order to characterize internal cognitive states. But is it possible to “mind-read” without the scanner? Capitalizing on the robust finding that the contents of working memory guide visual attention toward memory-matching objects, we trained a multivariate pattern classifier on behavioural indices of attentional guidance. Working memory representations were successfully decoded from behaviour alone, both within and between individuals. The current study provides a proof-of-concept for applying machine learning techniques to simple behavioural outputs (e.g., response times) in order to decode information about specific internal cognitive states.     

Satisfaction at last: Evidence for the “satisfaction” hypothesis for multiple-target search errors

ABSTRACT

Multiple-target visual searches are susceptible to Subsequent Search Miss (SSM) errors—a reduced accuracy for target detection after a previous target has already been detected. SSM errors occur in critical searches (e.g., evaluations of radiographs and airport luggage x-rays), and have proven to be a stubborn problem. A few SSM theories have been offered, and here we investigate the “satisfaction” account: failing to completely finish a search after having found a first target. Accuracy on a multiple-target search task was compared to both how long participants spent searching after finding a first target and their target sensitivity in a separate vigilance task. Less time spent searching and poor vigilance predicted higher SSM error rates. These results suggest that observers who are more likely to miss a second target are less likely to thoroughly search after finding a first target, thus offering some of the first evidence for the “satisfaction” account.     

Categorical target templates: Typical category members are found and identified quickly during word-cued search

What information do people use to guide search when they lack precise details about the appearance of their target? In this study, we employed categorical (word-cued) search and eye tracking, to examine how category typicality influences search performance. We found that typical category members were fixated and identified more quickly than atypical categories. This finding held when the participant was cued at the superordinate level (finding “clothing” among non-clothing items) or the basic level (finding a “shirt” among other clothing items). This suggests that categorical target templates may be constructed by piecing together features from the most typical category member(s).     

A reversal of the search asymmetry favouring negative schematic faces

Quite a number of studies have tested whether the affective valence of stimuli can guide attention in visual search. Studies using schematic affective faces frequently found a relative search asymmetry (RSA), with more efficient search for a negative face in a friendly crowd than vice versa. Whether, however, this effect relates to differences in affect or to the confounded differences in perceptual features is unknown. The present study proposes and tests a similarity-based account for the RSA. Experiments 1a and 1b first replicate the typical RSA. Experiment 2 shows that the stimulus could be simplified to some degree without losing the RSA. Experiments 3 and 4, finally, demonstrate that the RSA could be reversed by a rather simple stimulus change, that leaves the facial expression intact. It is concluded that the strong dependence of the RSA on stimulus factors seriously questions the claim that emotional factors drive the RSA.     

Failure to exploit learned spatial value information during visual search

ABSTRACT

In recent years there has been rapid proliferation of studies demonstrating how reward learning guides visual search. However, most of these studies have focused on feature-based reward, and there has been scant evidence supporting the learning of space-based reward. We raise the possibility that the visual search apparatus is impenetrable to spatial value contingencies, even when such contingencies are learned and represented online in a separate knowledge domain. In three experiments, we interleaved a visual choice task with a visual search task in which one display quadrant produced greater monetary rewards than the remaining quadrants. We found that participants consistently exploited this spatial value contingency during the choice task but not during the search task – even when these tasks were interleaved within the same trials and when rewards were contingent on response speed. These results suggest that the expression of spatial value information is task specific and that the visual search apparatus could be impenetrable to spatial reward information. Such findings are consistent with an evolutionary framework in which the search apparatus has little to gain from spatial value information in most real world situations.     

Episodic representation of diagnostic and nondiagnostic object colour

In three experiments, we investigated transsaccadic object file representations. In each experiment, participants moved their eyes from a central fixation cross to a saccade target located between two peripheral objects. During the saccade, this preview display was replaced with a target display containing a single object to be named. On trials in which the target identity matched one of the preview objects, its colour either matched or did not match the previewed object colour. The results indicated that colour changes disrupt perceptual continuity, but only for the class of objects for which colour is diagnostic of object identity. When the colour is not integral to identifying an object (for example, when the object is a letter or an object without a characteristic colour), object continuity is preserved regardless of changes to the object's colour. These results suggest that object features that are important for defining the object are incorporated into its episodic representation. Furthermore, the results are consistent with previous work showing that the quality of a feature's representation determines its importance in preserving continuity.     

Waldo reveals cultural differences in return fixations

ABSTRACT

Humans routinely perform visual search towards targets to adapt to the environment. These sequences of ballistic eye movements are shaped by a combination of top–down and bottom–up factors. Recent research documented that human observers display cultural-specific fixation patterns in a range of visual processing tasks. In particular, eye movement strategies extracting information from faces clearly differs between Western Caucasian (WC) and East Asian (EA) observers. However, whether such cultural differences are also present for visual scene processing remains debated. To this aim, we recorded the eye movements of WC and EA observers while they were solving visual search problems parametrically varying in difficulty: Where’s Waldo. Both groups had a comparable familiarity with the Waldo books reaching a comparable level of accuracy in target detection. Both cultural groups also showed a comparable temporal effect on inhibition of return, with longer fixation durations when saccades were performed to a return location compared to other locations. Westerners, however, located Waldo faster than Easterners. Interestingly, this modulation of speed was likely related to differences occurring on the low-level mechanisms of spatial inhibition of return, with EA observers returning more often to previously visited locations than the WC observers. This suboptimal eye movement strategy in the Easterners might be engendered by their cultural perceptual bias consisting in? a greater use of extra-foveal information. Overall, our data point towards the existence of a subtle, but significant difference in the processing of visual scenes across observers from different cultures during active visual search.     

Attributions for Memory Performance in Adulthood: Age Differences and Mediation Effects

We examined age differences in attributions to internal (controllable and uncontrollable), external (uncontrollable), and unstable factors for performance on a free recall memory task in 149 young, middle-aged, and older adults. Attributions varied by age and by level of memory performance. Middle-aged and older adults rated internal, uncontrollable factors (ability and genes) as more influential for high performance than for low performance, and they were less likely than young adults to attribute low performance to these factors. Within age groups, only the older adults rated memory ability as more influential than strategy use, even though they were as likely as the other age groups to use a categorization strategy. Attributions to both internal controllable (strategy use) and uncontrollable (ability) factors as well as to health were associated with better memory performance. These attributions partially mediated the relationship between age and memory performance. Thus, attributions may provide some insight into sources of age differences in memory performance.     

Age-related effects in inter-trial inhibition of attention

ABSTRACT

Young and older adults indentified the shape of a color oddball in a visual search task, and both showed faster and more accurate responses when the distractor color was passively viewed in the preceding target-absent trial than when the target color was previewed. This inter-trial effect, known as the distractor previewing effect (DPE), reflects an attentional bias that prevents attention from focusing on recently inspected features that failed to produce a target. The results showed that the DPE pattern was preserved across the lifespan, and that the age-related increase in the magnitude of the DPE appeared rooted in age-related slowing, suggesting substantial sparing of this inhibitory effect in old age.