Sustained-Paced Finger Tapping: A Novel Approach to Measure Internal Sustained Attention

Conscious but not thinking-Mind-blanks during visuomotor tracking: An fMRI study of endogenous attention lapses

Attention lapses (ALs) are complete lapses of responsiveness in which performance is briefly but completely disrupted and during which, as opposed to microsleeps, the eyes remain open. Although the phenomenon of ALs has been investigated by behavioural and physiological means, the underlying cause of an AL has largely remained elusive. This study aimed to investigate the underlying physiological substrates of behaviourally identified endogenous ALs during a continuous visuomotor task, primarily to answer the question: Were the ALs during this task due to extreme mind-wandering or mind-blanks? The data from two studies were combined, resulting in data from 40 healthy non-sleep-deprived subjects (20M/20F; mean age 27.1 years, 20-45). Only 17 of the 40 subjects were used in the analysis due to a need for a minimum of two ALs per subject. Subjects performed a random 2-D continuous visuomotor tracking task for 50 and 20 min in Studies 1 and 2, respectively. Tracking performance, eye-video, and functional magnetic resonance imaging (fMRI) were recorded simultaneously. A human expert visually inspected the tracking performance and eye-video recordings to identify and categorise lapses of responsiveness as microsleeps or ALs. Changes in neural activity during 85 ALs (17 subjects) relative to responsive tracking were estimated by whole-brain voxel-wise fMRI and by haemodynamic response (HR) analysis in regions of interest (ROIs) from seven key networks to reveal the neural signature of ALs. Changes in functional connectivity (FC) within and between the key ROIs were also estimated. Networks explored were the default mode network, dorsal attention network, frontoparietal network, sensorimotor network, salience network, visual network, and working memory network. Voxel-wise analysis revealed a significant increase in blood-oxygen-level-dependent activity in the overlapping dorsal anterior cingulate cortex and supplementary motor area region but no significant decreases in activity; the increased activity is considered to represent a recovery-of-responsiveness process following an AL. This increased activity was also seen in the HR of the corresponding ROI. Importantly, HR analysis revealed no trend of increased activity in the posterior cingulate of the default mode network, which has been repeatedly demonstrated to be a strong biomarker of mind-wandering. FC analysis showed decoupling of external attention, which supports the involuntary nature of ALs, in addition to the neural recovery processes. Other findings were a decrease in HR in the frontoparietal network before the onset of ALs, and a decrease in FC between default mode network and working memory network. These findings converge to our conclusion that the ALs observed during our task were involuntary mind-blanks. This is further supported behaviourally by the short duration of the ALs (mean 1.7 s), which is considered too brief to be instances of extreme mind-wandering. This is the first study to demonstrate that at least the majority of complete losses of responsiveness on a continuous visuomotor task are, if not due to microsleeps, due to involuntary mind-blanks.

Sustaining attention in visuomotor timing is associated with location-based binding

Maintaining focus of attention over prolonged periods can be challenging, especially when the target stimulus is absent from the temporal sequence. Prior research has shown that a temporal attentional cue filling in the temporal blank can improve sustained attention: in a sustained visual attention task requiring synchronizing finger tapping with a temporally regular sequence composed of brief flash disks interleaved with blank periods, task performance was improved when a continuous fixation point that served as a temporal attentional cue was presented superimposed on the disk stimulus. To test the hypothesis that binding the temporal attentional cue with the target temporal sequence by spatial overlapping is crucial for enhancing sustained attention, the present study conducted a series of three experiments that deconstructed the bound connection between the cue and the sequence stimulus. In Experiment 1, the cue was placed above or below a flash disk. In Experiment 2, the cue was between two vertically arranged flash disks. In Experiment 3, the cue was in a flash ring. No significant effect of sustained attention improvement was found in any of the three experiments. Experiment 4 further replicated these null results and the previously observed effect of sustained attention improvement when the temporal cue was superimposed on the sequence stimulus. Our finding demonstrates that binding by spatial overlapping during the temporal blank when the sequence stimulus is absent is critical for enhancing sustained attention, which should be beneficial for improving performance across a broader range of tasks that require prolonged maintenance of attention.

Effectiveness of a Serious Game Design and Game Mechanic Factors for Attention and Executive Function Improvement in the Elderly: A Pretest-Posttest Study

Attention allows us to focus and process information from our environment, and executive function enables us to plan, work, and manage our daily lives. As individuals become older, both of these cognitive abilities decline. It is essential for the elderly to perform more cognitive exercises. Previous studies have shown that arithmetic calculations require attention span and that playing video games requires executive function. Therefore, we developed a serious game involving mental arithmetic calculations specifically for improving attention span and executive functions. Our objective was to analyze the effectiveness of the game and the efficacy of the game’s mechanic factors affecting attention span and executive function in the elderly. Forty elderly volunteers who are over 60 years of age were invited to join an eight-week cognitive training program through an elderly social welfare center. Four assessment tests were used in pre-test and post-test before and after the training period. D-CAT and SAT are used for screening attention span; TMT-A and TMT-B are used for screening executive function. They were instructed to play the game for at least 15 min per day, 5 days per week, for a total of 8 weeks. There were three independent variables (difficulty, pressure, and competition) with two parameters that could be selected. A paired-sample t-test showed the effective results by comparing the pre-test scores and post-test scores of the cognitive training. There were significant improvements in attention span and executive functions. The mixed repeated-measure ANOVA and MANCOVA results showed that two game mechanic factors (difficulty and pressure) had a significant effect and an interaction effect, but the other factor (competition) had a non-significant effect. In conclusion, the game showed a significant enhancement in both attention span and executive functions after training, and the difficulty factor and the pressure factor were shown to have an effect, but the competition factor was shown to have no effect.