Task demands determine whether shape or arousal of a stimulus modulates competition for visual working memory resources

Towards enhanced performance: an integrated framework of emotional valence, arousal, and task demand

Extensive evaluations exist concerning the linkage between objective task demands and subsequent effects on user performance. However, the human user also experiences a range of emotions related to external task demands. Problematically, little is known about the associations between emotional valence, and arousal associated with the task demand-performance axis. In this paper, we advance a theoretical model concerning such interactive influences using three dimensions: (1) emotional valence, (2) arousal, and (3) task demand. The model evaluates the impact of these dimensions on user performance. It also identifies critical emotional user states, particularly those resulting in negative performance effects, as well as non-critical emotional states that can positively impact performance. Finally, we discuss the implications for affect-adaptive systems that can mitigate the impact of critical emotional states while leveraging the benefits of non-critical ones.

No evidence of attentional prioritization for threatening targets in visual search

Throughout human evolutionary history, snakes have been associated with danger and threat. Research has shown that snakes are prioritized by our attentional system, despite many of us rarely encountering them in our daily lives. We conducted two high-powered, pre-registered experiments (total N = 224) manipulating target prevalence to understand this heightened prioritization of threatening targets. Target prevalence refers to the proportion of trials wherein a target is presented; reductions in prevalence consistently reduce the likelihood that targets will be found. We reasoned that snake targets in visual search should experience weaker effects of low target prevalence compared to non-threatening targets (rabbits) because they should be prioritized by searchers despite appearing rarely. In both experiments, we found evidence of classic prevalence effects but (contrasting prior work) we also found that search for threatening targets was slower and less accurate than for nonthreatening targets. This surprising result is possibly due to methodological issues common in prior studies, including comparatively smaller sample sizes, fewer trials, and a tendency to exclusively examine conditions of relatively high prevalence. Our findings call into question accounts of threat prioritization and suggest that prior attention findings may be constrained to a narrow range of circumstances.

The interference of negative emotional stimuli on semantic vigilance performance in a dual-task setting

A large body of previous research has shown that emotional stimuli have an advantage in a wide variety of cognitive processes. This was mainly observed in visual search and working memory tasks. Emotionally charged objects draw and hold attention, are remembered better, and interfere more with the completion of the primary task than neutral ones. Therefore, it seems reasonable to assume that emotional stimuli also greatly affect sustained attention and vigilance decrement. In the present research, we investigated whether emotional stimuli demand more attentional resources than neutral ones in a dual-task paradigm. We adopted the abbreviated semantic discrimination vigilance task and measured participants' (N = 49) performance in a single-task and two dual-task settings. In the dual-task conditions, the visual semantic vigilance paradigm was combined with an auditory word recall task (with neutral or emotional stimuli). We found reduced vigilance and improved word recall performance in the emotional dual-task condition compared to the neutral dual-task and single-task conditions. The reduced performance was apparent throughout the task, while in the neutral conditions, participants' performance first increased and then dropped as time progressed. To conclude, our results indicate that emotional stimuli not only have an advantage in cognitive processing but also demand more attentional resources continuously while it is present compared to neutral stimuli. These results are consistent with the emotionality effect theory and evolutionary accounts of the neural circuits underlying motivated behaviors associated with critical survival needs.

Can the processing of task-irrelevant threatening stimuli be inhibited? - The role of shape and valence in the saliency of threatening objects

Numerous studies have demonstrated that attention is quickly oriented towards threatening stimuli, and that this attentional bias is difficult to inhibit. The root cause(s) of this bias may be attributable to the affective (e.g., valence) or visual features (e.g., shape) of threats. In two experiments (behavioral, eye-tracking), we tested which features play a bigger role in the salience of threats. In both experiments, participants looked for a neutral target (butterfly, lock) among other neutral objects. In half of the trials a threatening (snake, gun) or nonthreatening (but visually similar; worm, hairdryer) task-irrelevant distractor was also present at a near or far distance from the target. Behavioral results indicate that both distractor types interfered with task performance. Rejecting nonthreatening distractors as nontargets was easier when they were presented further from the target but distance had no effect when the distractor was threatening. Eye-tracking results showed that participants fixated less often (and for less time) on threatening compared to nonthreatening distractors. They also viewed targets for less time when a threatening distractor was present (compared to nonthreatening). Results suggest that visual features of threats are easier to suppress than affective features, and the latter may have a stronger role in eliciting attentional biases.

Motor inhibition impacts the motor interference effect of dangerous objects based on a prime-target grasping consistency judgment task

Whether motor inhibition impacts the motor interference effect of dangerous objects is controversial. Previous studies have manipulated task type and found that dangerous objects elicited increased motor inhibition compared to safe objects in the reachability judgment task but not in the categorization task. However, it was still unclear why motor inhibition was reduced for dangerous objects in the categorization task. We speculated that the activation strength of object affordance might modulate the occurrence of motor inhibition. To test this hypothesis, the present study designed a prime-target grasping consistency judgment task and manipulated target grips (power grip vs. precision grip), target dangerousness (dangerous vs. safe), and Go/NoGo (Go vs. NoGo). The results showed that under the condition of high activation strength of the target affordance (i.e., power grip targets), processing dangerous targets evoked increased motor inhibition (reflected by a more negative frontal N2 component) compared to safe targets and produced a motor interference effect in reaction time (RT). In contrast, under the condition of low target affordance activation strength (i.e., precision grip targets), processing dangerous targets facilitated RT compared to safe targets, with no difference found between the dangerous and safe conditions in the frontal N2 component. Furthermore, compared to safe objects, dangerous objects attracted more attention and recruited more cognitive resources to select appropriate responses to them. This study extended the findings of previous studies on the motor interference effect by highlighting the importance of activation strength for eliciting motor inhibition based on the prime-target consistency judgment task.

The bigger the threat, the longer the gaze? A cross-cultural study of Somalis and Czechs

High fear reaction, preferential attention, or fast detection are only a few of the specific responses which snakes evoke in humans. Previous research has shown that these responses are shared amongst several distinct cultures suggesting the evolutionary origin of the response. However, populations from sub-Saharan Africa have been largely missing in experimental research focused on this issue. In this paper, we focus on the effect of snake threat display on human spontaneous attention. We performed an eye-tracking experiment with participants from Somaliland and the Czechia and investigated whether human attention is swayed towards snakes in a threatening posture. Seventy-one Somalis and 71 Czechs were tested; the samples were matched for gender and comparable in age structure and education level. We also investigated the effect of snake morphotype as snakes differ in their threat display. We found that snakes in a threatening posture were indeed gazed upon more than snakes in a relaxed (non-threatening) posture. Further, we found a large effect of snake morphotype as this was especially prominent in cobras, less in vipers, and mostly non-significant in other morphotypes. Finally, despite highly different cultural and environmental backgrounds, the overall pattern of reaction towards snakes was similar in Somalis and Czechs supporting the evolutionary origin of the phenomenon. We concluded that human attention is preferentially directed towards snakes, especially cobras and vipers, in threatening postures.