Noise and attention span

Flexible processing of distractor stimuli under stress

Acute stress is assumed to affect executive processing of stimulus information, although extant studies have yielded heterogeneous findings. The temporal flanker task, in which a target stimulus is preceded by a distractor of varying utility, offers a means of investigating various components involved in the adjustment of information processing and conflict control. Both behavioral and EEG data obtained with this task suggest stronger distractor-related response activation in conditions associated with higher predictivity of the distractor for the upcoming target. In two experiments we investigated distractor-related processing and conflict control after inducing acute stress (Trier Social Stress Test). Although the stressed groups did not differ significantly from unstressed control groups concerning behavioral markers of attentional adjustment (i.e., Proportion Congruent Effect), or event-related sensory components in the EEG (i.e., posterior P1 and N1), the lateralized readiness potential demonstrated reduced activation evoked by (predictive) distractor information under stress. Our results suggest flexible adjustment of attention under stress but hint at decreased usage of nominally irrelevant stimulus information for biasing response selection.

When less is more

Easterbrook’s (1959) cue-utilization theory has been widely used to explain the inverted U-shaped relationship, initially established by Yerkes and Dodson, between emotional arousal and performance. The basic tenet of the theory assumes that high levels of arousal lead to restriction of the amount of information to which agents can pay attention. One fundamental derivative of the theory, as typically conceived in psychology, is the assumption that restriction of information or the ability to process a smaller set of data is fundamentally disadvantageous. To explore the merits of this point, we first argue that the relationship depicted by this collapsed version of the Yerkes-Dodson law is far too simplistic to account for the complex relationship between various cognitive functions and emotional arousal. Second, conceptualization of arousal as a unidimensional construct needs to be rejected. Finally, and most importantly, we challenge the notion that having more information available is necessarily preferable to having less information.

The impact of simulated MRI scanner background noise on visual attention processes as measured by the EEG

Environmental noise is known to affect personal well-being as well as cognitive processes. Besides daily life, environmental noise can also occur in experimental research settings, e.g. when being in a magnetic resonance scanner. Scanner background noise (SBN) might pose serious confounds for experimental findings, even when non-auditory settings are examined. In the current experiment we tested if SBN alters bottom-up and top-down related processes of selective visual attention mechanisms. Participants completed two blocks of a visual change detection task, one block in silence and one block under SBN exposure. SBN was found to decrease accuracy in measures of visual attention. This effect was modulated by the temporal occurrence of SBN. When SBN was encountered in the first block, it prevented a significant improvement of accuracy in the second block. When SBN appeared in the second block, it significantly decreased accuracy. Neurophysiological findings showed a strong frontal positivity shift only when SBN was present in the first block, suggesting an inhibitory process to counteract the interfering SBN. Common correlates of both top-down and bottom-up processes of selective visual attention were not specifically affected by SBN exposure. Further research appears necessary to entirely rule out confounds of SBN in assessing visual attention.

The impact of anxiety upon cognition: perspectives from human threat of shock studies

Anxiety disorders constitute a sizeable worldwide health burden with profound social and economic consequences. The symptoms are wide-ranging; from hyperarousal to difficulties with concentrating. This latter effect falls under the broad category of altered cognitive performance which is the focus of this review. Specifically, we examine the interaction between anxiety and cognition focusing on the translational threat of unpredictable shock paradigm; a method previously used to characterize emotional responses and defensive mechanisms that is now emerging as valuable tool for examining the interaction between anxiety and cognition. In particular, we compare the impact of threat of shock on cognition in humans to that of pathological anxiety disorders. We highlight that both threat of shock and anxiety disorders promote mechanisms associated with harm avoidance across multiple levels of cognition (from perception to attention to learning and executive function)-a "hot" cognitive function which can be both adaptive and maladaptive depending upon the circumstances. This mechanism comes at a cost to other functions such as working memory, but leaves some functions, such as planning, unperturbed. We also highlight a number of cognitive effects that differ across anxiety disorders and threat of shock. These discrepant effects are largely seen in "cold" cognitive functions involving control mechanisms and may reveal boundaries between adaptive (e.g., response to threat) and maladaptive (e.g., pathological) anxiety. We conclude by raising a number of unresolved questions regarding the role of anxiety in cognition that may provide fruitful avenues for future research.

Selective attention improves under stress: implications for theories of social cognition

Three influential perspectives of social cognition entail conflicting predictions regarding the selectivity of performance under stress. According to the attention view, selectivity to the task-relevant attribute improves under stress because of reduced utilization of task-irrelevant attributes. According to the capacity-resource approach, stress depletes attentional resources wherefore selectivity fails for all but chronically accessible information. A third perspective, ironic process theory, similarly holds that selective attention fails under stress but adds that task-irrelevant information is rendered hyperaccessible. The theoretical derivations were tested in a series of experiments using 2 classes of selectivity measures, with special care taken to control for hitherto neglected factors of context The results showed that the selectivity of attention improved under stress, consistent with the prediction of the attention view.

Trading accuracy for speed: gender differences on a Stroop task under mild performance anxiety

A standard Stroop task was used to examine the effect of performance anxiety on 58 male and 69 female undergraduates. Subjects were approached either by two casually dressed experimenters who did not stress speed or accuracy or by 4 or 5 formally dressed experimenters who stressed quick and accurate performance. Subjects were told the test would assess their "mental acuity"; their responses were visibly tape-recorded. Reaction times did not show differential response by anxiety condition; men and women showed different RTs only in the low-anxiety condition, with women performing significantly more slowly. There were no significant differences for the high-anxiety condition. Analysis of errors showed women were more accurate than men. Men traded accuracy for speed and may have been under equal performance stress in both situations. When performance was not stressed, women were slower and more accurate than men. When performance was stressed, women increased their speed to match that of men while maintaining their greater accuracy.

Annoyingness of Aircraft Noise in Relation to Cognitive Activity

College students were exposed by means of headphones to two kinds of aircraft noise (helicopter and jet) at three levels of loudness (60, 70, and 80 dB) while engaging in two tests of intelligibility and 12 cognitive tasks. In addition, the annoyingness of the noise was rated on a seven-point scale for each source/loudness combination in each task. Individual-differences measures (embedded figures, locus-of-control, and test anxiety) were also obtained. No performance difference related to noise was obtained in any of the cognitive tasks, and using the individual-difference measures as co-variates made no difference. In a second experiment a limited set of five modified cognitive tasks was used, again without producing any significant results. Finally, a third experiment utilized four cognitive tasks, a perceptual-motor task (Rotary Tracking) and intermittent rather than continuous noise, and yielded the same results. It was concluded that the failure to find performance differences on the cognitive tasks was probably due to the fact that concern for the welfare of the subjects limited the stimuli to loudness levels that were too low to be effective.