Neuroticism and vigilance revisited: A transcranial doppler investigation

The Role of State and Trait Self-Control on the Sustained Attention to Response Task

OBJECTIVE

This study aimed to assess the plausibility of self-control depletion, or ego-depletion, as the underlying cognitive resource responsible for performance decrements on the sustained attention to response task.

BACKGROUND

Researchers suggested that self-control is a limited cognitive resource used to complete a myriad of processes, including sustained attention. Past research showed that trait self-control affects some sustained attention tasks. However, little research has investigated the effect of self-control as a limited cognitive resource that varies over time (i.e., as a state-dependent variable).

METHODS

This experiment investigated the effect of self-control (trait and state) on a sustained motor-inhibition task (e.g., sustained attention to response task; SART). State self-control was manipulated using a between-subjects design-participants in the experimental condition completed a task designed to deplete state self-control prior to performing the SART while the control condition completed a modified version that did not deplete self-control.

RESULTS

Trait self-control predicted performance on the SART, but the depletion task (state self-control) had no detectable effect.

CONCLUSION

Given the evidence, it is unlikely that state self-control plays a causal role in performance decrements in the SART, but there appears to be some association between performance on the SART and trait self-control.

APPLICATION

Trait self-control ought to be considered in future work for personnel selection in real-world tasks that the SART models such as long-distance driving, air traffic control, and TSA operations.

Personality captures dissociations of subjective versus objective hearing in noise

Acoustic noise is pervasive in human environments. Some individuals are more tolerant to noise than others. We demonstrate the explanatory potential of Big-5 personality traits neuroticism (being emotionally unstable) and extraversion (being enthusiastic, outgoing) on subjective self-report and objective psycho-acoustic metrics of hearing in noise in two samples (total N = 1103). Under statistical control for demographics and in agreement with pre-registered hypotheses, lower neuroticism and higher extraversion independently explained superior self-reported noise resistance, speech-hearing ability and acceptable background noise levels. Surprisingly, objective speech-in-noise recognition instead increased with higher levels of neuroticism. In turn, the bias in subjectively overrating one's own hearing in noise decreases with higher neuroticism but increases with higher extraversion. Of benefit to currently underspecified frameworks of hearing in noise and tailored audiological treatments, these results show that personality explains inter-individual differences in coping with acoustic noise, which is a ubiquitous source of distraction and a health hazard.

Effects of state motivation in overload and underload vigilance task scenarios

Vigilance, or sustained attention, is the ability to maintain attention for prolonged periods of time. Interestingly, to date, few studies on vigilance have focused on the role of state motivation in sustaining attention. To address this disparity in the literature, the present study examined the effect of two types of state motivation on vigilance performance across task types (cognitive or sensory) and across the number of displays (one, two, or four). A sample of 105 participants completed a 24-min overload or underload vigilance task in a research laboratory. Participants were randomly assigned to either a cognitive or sensory vigilance task, and were randomly assigned to monitor one, two, or four displays for target stimuli. The results indicated that intrinsic state motivation predicted correct detection performance and state success motivation predicted sensitivity, but not false alarm performance, response bias, or global workload. We conclude with a discussion of the theoretical and practical applications of this research.

Does Depleting Self-Control Result in Poorer Vigilance Performance?

OBJECTIVE

To investigate whether depleting self-control prior to vigilance results in a steeper vigilance decrement.

BACKGROUND

The resource-control theory of vigilance asserts that an inherent bias toward self-generated mind-wandering draws attentional resources away from the primary task. This study seeks to test whether depleting self-control, the potential mechanism of self-generated mind-wandering, results in poorer vigilance performance.

METHOD

This study featured a between-subjects design where participants either completed a typing task that depleted self-control resources or a standard typing task that did not require self-control before performing a vigilance task. In the self-control depletion condition, participants typed a passage while omitting any "e" and "space" keys. In the standard typing task, participants typed the same passage without skipping any keys. Following both typing tasks, participants in both conditions completed an identical 12-min vigilance task.

RESULTS

Results demonstrated decreased accuracy and increased reaction times over time for both groups. Depleting self-control did not result in significant differences in accuracy, reaction time, nor a steeper vigilance decrement.

CONCLUSION

These results provide evidence against resource-control theory and self-control as an explanation for vigilance, and provide further support for cognitive resource theory as the predominant explanation for vigilance impairments.

APPLICATION

It is still unclear exactly what constitutes a "resource." A better understanding of the nature of these resources can help researchers and practitioners identify how they can be replenished, which could enhance human performance in situations requiring vigilance such as baggage screening.

Transcranial Doppler Sonography Reveals Reductions in Hemispheric Asymmetry in Healthy Older Adults during Vigilance

Given that older adults are remaining longer in the workforce, their ability to perform demanding cognitive tasks such as vigilance assignments needs to be thoroughly examined, especially since many vigilance assignments affect public safety (e.g., aviation, medicine and long distance driving). Previous research exploring the relation between aging and vigilance is conflicted, with some studies finding decreased vigilance performance in older adults but others finding no effect of age. We sought a better understanding of effects of age on vigilance by assessing neurophysiological change over the course of a vigil in young (aged 18–24) and healthy older (aged 66–77) adults. To measure temporal changes in cerebral blood flow, participants underwent functional transcranial doppler (fTCD) recording during a 1 h vigilance task. Based on research showing a compensatory effect of increased left hemisphere activation during vigilance in young adults and the “hemispheric asymmetry reduction in older adults” (HAROLD) model, we predicted that during vigilance our older adults would show greater left hemisphere activation but perform at a similar level compared to young adults. While cerebral blood flow velocity (CBFV) declined over time in both groups, only young adults showed the typical right-lateralized CBFV pattern. Older adults showed greater left hemisphere activation consistent with the HAROLD model. However, the increased left hemisphere activation did not appear to be compensatory as the older adults performed at a significantly lower level compared to young adults over the vigil. Findings are discussed in terms of the HAROLD model of healthy aging and the resource theory of vigilance.