The development of foraging organization

One factor to bind them all: visual foraging organization to predict patch leaving behavior with ROC curves

Predicting quitting rules is critical in visual search: Did I search enough for a cancer nodule in a breast X-ray or a threat in a baggage airport scanner? This study examines the predictive power of search organization indexes like best-r, mean ITD, PAO, or intersection rates as optimal criteria to leave a search in foraging (looking for several targets among distractors). In a sample of 29 adults, we compared static and dynamic foraging. Also, we reanalyze data from diverse foraging tasks in the lifespan already published to replicate results. Using ROC curves, all results consistently show that organization measures outperform classic intake rates commonly used in animal models to predict optimal human quitting behavior. Importantly, a combination of organization and traditional intake rates within a unitary factor is the best predictor. Our findings open a new research line for studying optimal decisions in visual search tasks based on search organization.

The effects of visual and auditory synchrony on human foraging

Can synchrony in stimulation guide attention and aid perceptual performance? Here, in a series of three experiments, we tested the influence of visual and auditory synchrony on attentional selection during a novel human foraging task. Human foraging tasks are a recent extension of the classic visual search paradigm in which multiple targets must be located on a given trial, making it possible to capture a wide range of performance metrics. Experiment 1 was performed online, where the task was to forage for 10 (out of 20) vertical lines among 60 randomly oriented distractor lines that changed color between yellow and blue at random intervals. The targets either changed colors in visual synchrony or not. In another condition, a non-spatial sound additionally occurred synchronously with the color change of the targets. Experiment 2 was run in the laboratory (within-subjects) with the same design. When the targets changed color in visual synchrony, foraging times were significantly shorter than when they randomly changed colors, but there was no additional benefit for the sound synchrony, in contrast to predictions from the so-called "pip-and-pop" effect (Van der Burg et al., Journal of Experimental Psychology, 1053-1065, 2008). In Experiment 3, task difficulty was increased as participants foraged for as many 45° rotated lines as possible among lines of different orientations within 10 s, with the same synchrony conditions as in Experiments 1 and 2. Again, there was a large benefit of visual synchrony but no additional benefit for sound synchronization. Our results provide strong evidence that visual synchronization can guide attention during multiple target foraging. This likely reflects the local grouping of the synchronized targets. Importantly, there was no additional benefit for sound synchrony, even when the foraging task was quite difficult (Experiment 3).

The time course of visual foraging in the lifespan: Spatial scanning, organization search, and target processing

Visual foraging is a variant of visual search, consisting of searching for an undetermined number of targets among distractors (e.g., looking for various LEGO pieces in a box). Under non-exhaustive tasks, the observer scans the display, picking those targets needed, not necessarily all of them, before leaving the search. To understand how the organization of such natural foraging tasks works, several measures of spatial scanning and organization have been proposed in the exhaustive foraging literature: best-r, intertarget distances, PAO, and target intersections. In the present study, we apply these measures and new Bayesian indexes to determine how the time course of visual foraging is organized in a dynamic non-exhaustive paradigm. In a large sample of observers (279 participants, 4-25 years old), we compare feature and conjunction foraging and explore how factors like set size and time course, not previously tested in exhaustive foraging, might affect search organization in non-exhaustive dynamic tasks. The results replicate previous findings showing younger observers' searching being less organized, feature conditions being more organized than conjunction conditions, and organization leading to a more effective search. Interestingly, observers tend to be less organized as set size increases, and search is less organized within a patch as it advances in time: Search organization decreases when search termination is coming, suggesting organization measures as potential clues to understand quitting rules in search. Our results highlight the importance of studying search organization in foraging as a critical source of understanding complex cognitive processes in visual search.

I can look for it! Modulation of a concurrent Visual Working Memory task in Visual Search in development

Daily classroom activities that require children to perform visual search (VS) tasks are common across all educational levels: from searching for a missing piece of a puzzle in kindergarten to solving equations in college. However, VS tasks are often not performed in isolation, but rather students are maintaining information related to an ongoing task that loads working memory (WM). Unfortunately, it is still unclear how these processes interact and evolve in development. The present work aims to study how a concurrent visual WM (VWM) load can modulate VS performance based on the Developmental Model of Endogenous Mental Attention (Pascual-Leone and Johnson, 1999, 2005, 2021). A sample of kindergarten, elementary (2nd and 4th grades), middle school (6th grade), and college students looked for real-world photorealistic targets while maintaining similar objects in VWM in a dual-task paradigm. VWM load was manipulated using high and low memory load conditions. Additionally, looking for potential modulations related to individual differences, we studied the relationship between IQ, VWM span, and executive functions with VS efficiency. Finally, we also registered reported measures of potential strategies employed during the VS task. The results from a large sample of 147 participants between 5 and 25 years old revealed that even the youngest children could efficiently perform a VS task with a concurrent VWM load, replicating previous results found in adulthood. However, we found a slight increase in false alarms and commission errors when memory was highly loaded for all the participants regardless of age. As expected, we found positive correlations between VS efficiency and IQ and VWM span measures. Interestingly, the proportion of participants who used tracking organization strategies increased with age in all cases. However, although cognitive strategies to remember the target became more complex as age increased, it was only significant under the low VWM load conditions. The results seem relevant to understanding the development of VS based on the Model of Endogenous Mental Attention and the design of training programs to improve attention. The implications in educational contexts are discussed and are especially relevant for students with learning disabilities or attention problems.

Advances in the application of a computational Theory of Visual Attention (TVA): Moving towards more naturalistic stimuli and game-like tasks

The theory of visual attention, “TVA”, is an influential and formal theory of attentional selection. It is widely applied in clinical assessment of attention and fundamental attention research. However, most TVA-based research is based on accuracy data from letter report experiments performed in controlled laboratory environments. While such basic approaches to questions regarding attentional selection are undoubtedly useful, recent technological advances have enabled the use of increasingly sophisticated experimental paradigms involving more realistic scenarios. Notably, these studies have in many cases resulted in different estimates of capacity limits than those found in studies using traditional TVA-based assessment. Here we review recent developments in TVA-based assessment of attention that goes beyond the use of letter report experiments and experiments performed in controlled laboratory environments. We show that TVA can be used with other tasks and new stimuli, that TVA-based parameter estimation can be embedded into complex scenarios, such as games that can be used to investigate particular problems regarding visual attention, and how TVA-based simulations of “visual foraging” can elucidate attentional control in more naturalistic tasks. We also discuss how these developments may inform future advances of TVA.