Pupillary correlates of lapses of sustained attention

The current study examined the extent to which pupillary responses (both pretrial baseline and phasic responses) would accurately track lapses of attention as predicted by theories of locus coeruleus norepinephrine (LC-NE) functioning. Participants performed a sustained attention task while pupil responses were continuously recorded. Periodically during the task, participants were presented with thought probes to determine if they were on or off task. The results suggested the pupillary responses accurately distinguished on from off-task states. Importantly, pretrial baseline pupil responses distinguished different types of lapses of attention, with inattentive and mind-wandering states being associated with small pretrial baseline pupil diameters on average and distracted states being associated with larger pretrial baseline pupil diameters on average compared to focused states. These results support the notion that pupil diameter is sensitive to different types of lapses of attention which may be associated with different LC-NE modes.     

Natural scene stimuli and lapses of sustained attention

We conducted two experiments using naturalistic scene stimuli to test the resource theory and mindlessness theory of sustained attention. In experiment 1, 28 participants completed a traditional formatted vigilance task consisting of non-repeating forest or urban picture stimuli as target stimuli. Participants filled out pre- and post-task assessments of arousal and conscious thoughts. There was still a vigilance decrement, despite non-repetitive, natural target stimuli. Participants found the task demanding and were actively engaged in the task. In experiment 2, 25 participants completed a Sustained Attention to Response Task (SART) using the stimuli from experiment 1. Participants performed significantly worse on this SART than either brain injury patients or controls performing equivalent numeric stimuli SARTs have in previous studies. Participants thought the task was demanding and they were actively engaged with the task. Overall, the results of both studies support a resource theory of sustained attention lapses, not a mindlessness theory.     

Attention failures versus misplaced diligence: separating attention lapses from speed-accuracy trade-offs

In two studies of a GO-NOGO task assessing sustained attention, we examined the effects of (1) altering speed-accuracy trade-offs through instructions (emphasizing both speed and accuracy or accuracy only) and (2) auditory alerts distributed throughout the task. Instructions emphasizing accuracy reduced errors and changed the distribution of GO trial RTs. Additionally, correlations between errors and increasing RTs produced a U-function; excessively fast and slow RTs accounted for much of the variance of errors. Contrary to previous reports, alerts increased errors and RT variability. The results suggest that (1) standard instructions for sustained attention tasks, emphasizing speed and accuracy equally, produce errors arising from attempts to conform to the misleading requirement for speed, which become conflated with attention-lapse produced errors and (2) auditory alerts have complex, and sometimes deleterious, effects on attention. We argue that instructions emphasizing accuracy provide a more precise assessment of attention lapses in sustained attention tasks.     

Schizotypy and sustained attention

We examined sustained attention in 32 schizotypic and 43 normal control subjects from a large, randomly ascertained nonclinical university population. Schizotypy status was determined with the Perceptual Aberration Scale. Sustained attention was measured with the Continuous Performance Test-Identical Pairs. Schizotypic subjects displayed significantly poorer sustained-attention performance than did control subjects, as measured by d and overall hit rate. Although schizotypic subjects evidenced greater levels of anxiety and depression, sustained-attention performance was not significantly associated with these mental state factors. Our results provide evidence for a subtle sustained-attention deficit among schizotypes and are interpreted in light of previous attention research with actual schizophrenic patients as well as children at risk for schizophrenia. Utility of the psychometric high-risk strategy in psychopathology research is discussed.     

Everyday attention lapses and memory failures: the affective consequences of mindlessness

We examined the affective consequences of everyday attention lapses and memory failures. Significant associations were found between self-report measures of attention lapses (MAAS-LO), attention-related cognitive errors (ARCES), and memory failures (MFS), on the one hand, and boredom (BPS) and depression (BDI-II), on the other. Regression analyses confirmed previous findings that the ARCES partially mediates the relation between the MAAS-LO and MFS. Further regression analyses also indicated that the association between the ARCES and BPS was entirely accounted for by the MAAS-LO and MFS, as was that between the ARCES and BDI-II. Structural modeling revealed the associations to be optimally explained by the MAAS-LO and MFS influencing the BPS and BDI-II, contrary to current conceptions of attention and memory problems as consequences of affective dysfunction. A lack of conscious awareness of one's actions, signaled by the propensity to experience brief lapses of attention and related memory failures, is thus seen as having significant consequences in terms of long-term affective well-being.     

Effect of attention control on sustained attention during induced anxiety

Anxiety has wide-reaching and complex effects on cognitive performance. Although it can intrude on cognition and interfere with performance, it can also facilitate information processing and behavioural responses. In a previous study, we showed that anxiety induced by threat of shock facilitates performance on the Sustained Attention to Response Task, a vigilance test, which probes response inhibition to infrequent nogo stimuli. The present study sought to identify factors that may have contributed to such improved performance, including on- and off-task thinking (assessed with thought probes) and individual differences in attention control, as measured with the Attention Control Scale. Replicating our prior finding, we showed that shock threat significantly reduced errors of commission on the nogo trials. However, we extended this finding in demonstrating that this effect was driven by subjects with low attention control. We therefore confirm that anxiety increases inhibitory control of prepotent responses—a mechanism which is adaptive under threat—and show that this effect is greater in those who rely more upon such prepotent responding, i.e., those with low attentional control.     

How facial attractiveness affects sustained attention

The present study investigated whether and how facial attractiveness affects sustained attention. We adopted a multiple‐identity tracking paradigm, using attractive and unattractive faces as stimuli. Participants were required to track moving target faces amid distractor faces and report the final location of each target. In Experiment 1, the attractive and unattractive faces differed in both the low‐level properties (i.e., luminance, contrast, and color saturation) and high‐level properties (i.e., physical beauty and age). The results showed that the attractiveness of both the target and distractor faces affected the tracking performance: The attractive target faces were tracked better than the unattractive target faces; when the targets and distractors were both unattractive male faces, the tracking performance was poorer than when they were of different attractiveness. In Experiment 2, the low‐level properties of the facial images were equalized. The results showed that the attractive target faces were still tracked better than unattractive targets while the effects related to distractor attractiveness ceased to exist. Taken together, the results indicate that during attentional tracking the high‐level properties related to the attractiveness of the target faces can be automatically processed, and then they can facilitate the sustained attention on the attractive targets, either with or without the supplement of low‐level properties. On the other hand, only low‐level properties of the distractor faces can be processed. When the distractors share similar low‐level properties with the targets, they can be grouped together, so that it would be more difficult to sustain attention on the individual targets.     

Learning-disordered children's evoked potentials during sustained attention

Evoked potentials and performance of 19 learning-disordered (LD) and 19 normally achieving children were studied in two versions of the Continuous Performance Test (CPT). In both CPT procedures, LD children made more errors of omission and commission than did normal children. Evoked potential differences between groups were especially prominent in the more difficult BX version of the CPT. LD children displayed significantly smaller late positive components (LPC) of the evoked potential to critical stimuli in the task. There were no LPC differences between diagnostic groups for noncritical stimulus categories. The results suggest a deficit in behavioral and cortical indices of sustained attention among LD children.This research is based on a doctoral dissertation in psychology submitted by the first author (Dainer, 1980) and supervised by the second author. The research was partly supported by NIMH Grant MH 32103 and New York State Health Research Council Contract 1396 to the second author. We are grateful to the Strong Memorial Hospital Learning Disorders Clinic; B.O.C.E.S. School #1, Fairport, New York; Rochester Learning Disabilities Association; and Winifred Stebbins for referring learning-disordered children, and to the Rochester Central YMCA for referring normally achieving children. The University of Rochester College of Arts and Science provided partial support for computer funds. For their assistance, we are grateful to Lance Bauer, John Chapman, Michael Davidson, Dale McAdam, James Metz, and Lawrence Ota.     

Schizotypy and sustained attention: confirming evidence from an adult community sample

Sustained attention deficits represent one of the most robust findings in the study of schizophrenia and schizotypy. However, very little is known about the nature of sustained attention performance and schizotypy in the general adult population. The present study assessed sustained attention performance in a large, normative adult community sample (N = 305) with no history of psychosis using the Continuous Performance Test-identical pairs version (CPT-IP). Associations between overall CPT-IP performance and schizotypal personality disorder features, controlling for the effects of age, sex, and educational level, revealed diminished sensitivity (d', discriminability), and increased random errors were related to increased reality distortion features. These data, drawn from a general population sample, provided support for overall sustained attention deficits as an endophenotype for schizophrenia liability.     

Effects of depression on expectancy in sustained attention

The effects of expectancies generated during a pretest on the subsequent vigilance performance of depressed and nondepressed observers were assessed. Among the nondepressed, those who were exposed to a high signal probability during the pretest detected more signals in the main watch than those exposed to a low pretest probability, regardless of the signal probability in the vigil itself (high or low). This expectancy effect was not evident among the depressed. The vigilance decrement in both subject categories was steeper under conditions of low as compared to high test probability. These results indicate that depressed monitors do not demonstrate a deficit in attentional capacity. It is suggested that the nonperseveration of pretest expectancies among the depressed may stem from a lack of motivation to effortfully process information in the same manner as nondepressed observers.The authors would like to thank Mark Scerbo and Tom Lanzetta for their technical assistance.     

Event asynchrony and signal regularity in sustained attention

Subjects monitored the repetitive presentation of a vertically oriented line of light (background events) for occasional increments in the height of the line (critical signals). Signals for detection occurred in either a temporally regular or an irregular manner and were blended within a background of temporally synchronous (regular) or asynchronous (irregular) background events. The vigilance decrement, as reflected by a decline in perceptual sensitivity (A‘), during the watch was eliminated when critical signals appeared regularly within a synchronous event context. By contrast, in the context of event asynchrony, regular signal appearances exacerbated the decrement. The results highlight the importance of event asynchrony as a factor in vigilance performance, and link vigilance to a growing list of psychological processes that are dependent upon contextual rhythmicity. This report was completed while Joel S. Warm was a National Science Foundation senior postdoctoral fellow at the National Institute of Occupational Safety and Health Taft Laboratory, Cincinnati, Ohio.     

Evidence for a cognitive control network for goal-directed attention in simple sustained attention

The deterioration of performance over time is characteristic for sustained attention tasks. This so-called “performance decrement” is measured by the increase of reaction time (RT) over time. Some behavioural and neurobiological mechanisms of this phenomenon are not yet fully understood. Behaviourally, we examined the increase of RT over time and the inter-individual differences of this performance decrement. On the neurophysiological level, we investigated the task-relevant brain areas where neural activity was modulated by RT and searched for brain areas involved in good performance (i.e. participants with no or moderate performance decrement) as compared to poor performance (i.e. participants with a steep performance decrement). For this purpose, 20 healthy, young subjects performed a carefully designed task for simple sustained attention, namely a low-demanding version of the Rapid Visual Information Processing task. We employed a rapid event-related functional magnetic resonance imaging (fMRI) design. The behavioural results showed a significant increase of RT over time in the whole group, and also revealed that some participants were not as prone to the performance decrement as others. The latter was statistically significant comparing good versus poor performers. Moreover, high BOLD-responses were linked to longer RTs in a task-relevant bilateral fronto-cingulate-insular-parietal network. Among these regions, good performance was associated with significantly higher RT-BOLD correlations in the pre-supplementary motor area (pre-SMA). We concluded that the task-relevant bilateral fronto-cingulate-insular-parietal network was a cognitive control network responsible for goal-directed attention. The pre-SMA in particular might be associated with the performance decrement insofar that good performers could sustain activity in this brain region in order to monitor performance declines and adjust behavioural output.     

Age effects on a nonverbal auditory sustained attention task

A nonverbal auditory test of sustained attention was administered to 20 young and 20 elderly women, screened to ensure good health. Groups were matched for intelligence. Older subjects performed as accurately as younger subjects. Neither group showed increases in response latency as a function of time spent on test. Older subjects took longer to respond than younger subjects, but only for a particular combination of stimulus duration and order of presenting stimulus durations. When subjects were presented long tones first, there was no difference in response latency associated with age or stimulus duration. When short tones were presented first, older subjects were slower than younger subjects in both duration conditions and in response to long tones were slower than all other subjects.     

Conscious thought and the sustained attention to response task

We investigated the properties of the sustained attention to response task (SART). In the SART, participants respond to frequent (high probability of occurrence) neutral signals and are required to withhold response to rare (low probability of occurrence) critical signals. We examined whether SART performance shows characteristics of speed–accuracy tradeoffs and in addition, we examined whether SART performance is influenced by prior exposure to emotional picture stimuli. Thirty-six participants in this study performed SARTs after being exposed to neutral and negative picture stimuli. Performance in the SART changed rapidly over time and there was a high correlation between participants errors of commission rate and their reaction time to the neutral targets (r = −.61). Regardless of exposure self-reported thoughts significantly correlated with both errors of commission and reaction times. Overall, the results support the view that the SART is a better measure of impulsive responding than sustained attention.     

Retro-cue benefits in working memory without sustained focal attention

In working memory (WM) tasks, performance can be boosted by directing attention to one memory object: When a retro-cue in the retention interval indicates which object will be tested, responding is faster and more accurate (the retro-cue benefit). We tested whether the retro-cue benefit in WM depends on sustained attention to the cued object by inserting an attention-demanding interruption task between the retro-cue and the memory test. In the first experiment, the interruption task required participants to shift their visual attention away from the cued representation and to a visual classification task on colors. In the second and third experiments, the interruption task required participants to shift their focal attention within WM: Attention was directed away from the cued representation by probing another representation from the memory array prior to probing the cued object. The retro-cue benefit was not attenuated by shifts of perceptual attention or by shifts of attention within WM. We concluded that sustained attention is not needed to maintain the cued representation in a state of heightened accessibility.     

Search asymmetry, sustained attention, and response inhibition

In the present experiment, we used search asymmetry to test whether the sustained attention to response task is a better measure of response inhibition or sustained attention. Participants performed feature present and feature absent target detection tasks using either a sustained attention to response task (SART; high Go low No-Go) or a traditionally formatted task (TFT; high No-Go low Go) response format. In addition to performance, we employed functional near infrared spectroscopy (fNIRS) to measure lateral cerebral oxygenation levels and self-reports of Tense Arousal, Energetic Arousal, task related and unrelated thoughts occurring during the tasks. Detections were lower and reaction times longer in the feature absent search than the feature present search regardless of response format. Detections were lower, but reaction times shorter in the SART than the TFT regardless of feature search. Greater right than left frontal hemisphere activation occurred in the SART than the TFT. In addition, the SART was more fatiguing based on self-reports than the TFT, but there were no differences in Task-Unrelated Thoughts across task conditions. Overall, the results suggest the SART places high response inhibition, not necessarily sustained attention, demands on participants.     

EEG correlates of sustained attention: Hemispheric and sex differences

Subjects were presented with sets of four digits, and had to respond only when all the digits in a set were odd. The EEG was measured from occipital-parietal derivations over the left and right hemispheres, and the energy within each of five frequency bands was integrated over 3-sec epochs corresponding to the presentation of individual sets of digits. The EEG abundance was found to be lower the more a digit set resembled a signal, but hemisphere differences in this effect tended to be small and to occur only in certain frequency bands. The effect for stimulus type changed over time in some frequency bands, but there were no differences between the hemispheres in this change. Nor were sex differences in lateralization found. Reaction time was found to correlate positively with (a) EEG abundance, and (b) EEG differentiation of stimuli, in the theta and low alpha frequency bands.