Ada Mishler

Redundancy gain for categorical targets depends on display configuration and duration

ABSTRACT Redundancy gain is an improvement in speeded target detection when the number of targets associated with a single response is increased within a single display. The effect has been clearly demonstrated with specific targets, but it is not clear if it occurs in categorization tasks with non-identical targets. The current study tested the effect of target redundancy on speed and accuracy in a go/no-go categorization task. Targets were digits tilted 45° to the left, and were displayed in unilateral, bilateral, or central displays for either 1500 ms or 100 ms. Redundancy gain only occurred for brief targets displayed bilaterally in the upper visual field. The results indicate that redundancy gain is possible for categorization tasks with some bilateral configurations, supporting a role for interhemispheric processing in redundancy gain. Additionally, the results may indicate that processing strategies mask redundancy gain when participants can view targets for a long period of time.

You Can’t Catch ‘Em All: Inattention During Active Mobile Gaming.

Using a mobile device while driving or walking leads to inattention. The popular augmented reality mobile game Pokémon GO (PGO) requires users to walk in order to play, creating a possible multitasking conflict as users interact with the game. This study required three groups to walk a predefined course while either playing PGO, texting with a confederate, or walking naturally. After the walk, participants were given a surprise memory test for what they saw while walking the course, also rating confidence in their responses. Accuracy was significantly lower only in the texting condition; however, both multitasking conditions had significantly lower confidence ratings for their responses as well as more safety infractions. Overall, while the PGO participants did not suffer the same attentional costs as the texting condition, their unsafe walking behavior and low confidence in their responses may still lead to dangerous situations.

Improving Wayfinding for Older Users With Selective Attention Deficits

Older adults experience difficulties with navigating their environments and may need to rely on signs more heavily than younger adults. However, older adults also experience difficulties with focusing their visual attention, which suggests that signs need to be designed with the goal of making it as easy as possible to attend to them. This article discusses some design principles that may be especially important to compensate for declining attentional focus. These principles include distinctiveness, consistent appearance and location, standardized images, simplicity, isolation from other elements of the environment, and reassurance about the current route.

Absence of distracting information explains the redundant signals effect for a centrally presented categorization task

The redundant signals effect, a speed-up in response times with multiple targets compared to a single target in one display, is well-documented, with some evidence suggesting that it can occur even in conceptual processing when targets are presented bilaterally. The current study was designed to determine whether or not category-based redundant signals can speed up processing even without bilateral presentation. Toward that end, participants performed a go/no-go visual task in which they responded only to members of the target category (i.e., they responded only to numbers and did not respond to letters). Numbers and letters were presented along an imaginary vertical line in the center of the visual field. When the single signal trials contained a nontarget letter (Experiment 1), there was a significant redundant signals effect. The effect was not significant when the single-signal trials did not contain a nontarget letter (Experiments 2 and 3). The results indicate that, when targets are defined categorically and not presented bilaterally, the redundant signals effect may be an effect of reducing the presence of information that draws attention away from the target. This suggests that redundant signals may not speed up conceptual processing when interhemispheric presentation is not available.

Coactivation in Peripheral Triple Conjunction Search

The triple conjunction effect (TCE) is characterized by faster response time (RT) when a target is defined by a conjunction of three features than when it is defined by two features. One possible, but unaccounted for, explanation of this finding is feature coactivation, in which information from multiple features combines to reach a response threshold more quickly than separate single features. The purpose of the current study was to determine if the TCE could be attributed to feature coactivation; in addition, we explored whether or not the TCE occurs in peripheral visual search. Participants searched for the presence of a target letter in 6 counterbalanced blocks, with 4 blocks of conjunction searches (2 of color and orientation, and 2 of form and orientation) and 2 blocks of triple conjunction searches (color, form, and orientation). Each trial contained 4 or 8 letters subtending 2° by 2° on an invisible circle 8° from the center of the display. Trials were terminated if participants moved their eyes more than 2.75° from the center or did not respond within 4 seconds. Each conjunction search had 4 types of distractors, and each triple conjunction search had 3 types of distractors. A second experiment had 3 distractor types in all search conditions, to rule out distractor homogeneity effects. In both experiments, RT was faster in triple conjunction (~206 ms) than conjunction search. The Townsend Bound, a race model prediction about the redundant target RT distribution, was violated at several quantiles (5-16 of 18 quantiles, depending on experiment, set size, and target), providing evidence for coactivation when RTs were averaged across participants. Anderson-Darling tests indicated that most participants individually violated the Townsend Bound, providing further evidence for coactivation. The results suggest that the peripheral TCE is at least partially due to coactivation of target-relevant features. Meeting abstract presented at VSS 2015.