Eye movement feedback fails to improve visual search performance

Abstract Many real-world searches (e.g., radiology and baggage screening) have rare targets. When targets are rare, observers perform rapid, incomplete searches, leading to higher miss rates. To improve search for rare (10% prevalence) targets, we provided eye movement feedback (EMF) to observers during their searches. Although the nature of the EMF varied across experiments, each method informed observers about the regions of the display that had not yet been inspected. We hypothesized that feedback would help guide attention to unsearched areas and increase the proportion of the display searched before making a target-absent response, thereby increasing accuracy. An eye tracker was used to mark fixated areas by either removing a semiopaque gray overlay (Experiments 1 and 4) as portions of the display were fixated or by adding the overlay once the eye left a segment of the image (Experiments 2 and 4). Experiment 3 provided automated EMF, such that a new region was uncovered every 540 milliseconds. Across experiments, we varied whether people searched for “Waldo” in images from “Where’s Waldo?” search books or searched for a T among offset Ls. We found weak evidence that EMF improves accuracy in Experiment 1. However, in the remaining experiments, EMF had no effect (Experiment 4), or even reduced accuracy (Experiments 2 and 3). We conclude that the one positive result we found is likely a Type I error and that the EMF method that we used is unlikely to improve visual search performance

ProcessBasedFBAllData.xlsx

Data set from the submission to CRPI titled, "Process Based Feedback Does Not Improve Visual Search for Rare Targets.

Motor Biases Do Not Account for the Low Prevalence Effect

Motor Bias experiments 1 and 2 dat

(2A) Principle display panels (PDP for the four brands of cereal (top row) and four brands of crackers (middle row) that were created (in the form of packages) for the experiment. (2B) PDP of a single brand of cereal depicted at high and low levels of health which include the corresponding traffic light labels. (2C) Illustration of the standard Nutrition Facts Panel (NFP) that appears on the panel immediately to the right of the PDP on cereal boxes.

<p>(2A) Principle display panels (PDP for the four brands of cereal (top row) and four brands of crackers (middle row) that were created (in the form of packages) for the experiment. (2B) PDP of a single brand of cereal depicted at high and low levels of health which include the corresponding traffic light labels. (2C) Illustration of the standard Nutrition Facts Panel (NFP) that appears on the panel immediately to the right of the PDP on cereal boxes.</p

Estimated mean total eye-gaze time spent on the Nutrition Facts Panel for cereal and cracker packages that did and did not include an FOP label.

<p>A 2-way interaction was apparent between product type and whether an FOP label was present or not, P<0.05.)</p

Plots the percentage of each type of nutritional label that has been fixated as a function of viewing time.

<p>Data were collapsed across participants so the percentage was based on the number of labels fixated out of the 220 total labels per label type (4 labels x 55 participants)</p

Participant Characteristics.

<p>Participant Characteristics.</p

(1A) Examples of Non-Directive labels (1B) Examples of Semi- directive FOPs (1C) Examples of Directive FOPs.

<p>(1A) Examples of Non-Directive labels (1B) Examples of Semi- directive FOPs (1C) Examples of Directive FOPs.</p