Interactive effects of the COMT gene and training on individual differences in supervisory control of unmanned vehicles.

OBJECTIVE: We examined whether a gene known to influence dopamine availability in the prefrontal cortex is associated with individual differences in learning a supervisory control task. BACKGROUND: Methods are needed for selection and training of human operators who can effectively supervise multiple unmanned vehicles (UVs). Compared to the valine (Val) allele, the methionine (Met) allele of the COMT gene has been linked to superior executive function, but it is not known whether it is associated with training-related effects in multi-UV supervisory control performance. METHOD: Ninety-nine healthy adults were genotyped for the COMT Val158Met single nucleotide polymorphism (rs4680) and divided into Met/Met, Val/Met, and Val/Val groups. Participants supervised six UVs in an air defense mission requiring them to attack incoming enemy aircraft and protect a no-fly zone from intruders in conditions of low and high task load (numbers of enemy aircraft). Training effects were examined across four blocks of trials in each task load condition. RESULTS: Compared to the Val/Met and Val/Val groups, Met/Met individuals exhibited a greater increase in enemy targets destroyed and greater reduction in enemy red zone incursions across training blocks. CONCLUSION: Individuals with the COMT Met/Met genotype can acquire skill in executive function tasks, such as multi-UV supervisory control, to a higher level and/or faster than other genotype groups. APPLICATION: Potential applications of this research include the development of individualized training methods for operators of multi-UV systems and selecting personnel for complex supervisory control tasks.

Enhancing dual-task performance with verbal and spatial working memory training: continuous monitoring of cerebral hemodynamics with NIRS.

To better understand the mechanisms by which working memory training can augment human performance we continuously monitored trainees with near infrared spectroscopy (NIRS) while they performed a dual verbal-spatial working memory task. Linear mixed effects models were used to model the changes in cerebral hemodynamic response as a result of time spent training working memory. Nonlinear increases in left dorsolateral prefrontal cortex (DLPFC) and right ventrolateral prefrontal cortex (VLPFC) were observed with increased exposure to working memory training. Adaptive and yoked training groups also showed differential effects in rostral prefrontal cortex with increased exposure to working memory training. There was also a significant negative relationship between verbal working memory performance and bilateral VLPFC activation. These results are interpreted in terms of decreased proactive interference, increased neural efficiency, reduced mental workload for stimulus processing, and increased working memory capacity with training.

The impact of visual scanning in the laparoscopic environment after engaging in strain coping.

OBJECTIVE: We aimed to determine whether visual scanning has a detrimental impact on the monitoring of critical signals and the performance of a concurrent laparoscopic training task after participants engaged in Hockey's strain coping. Strain coping refers to straining cognitive (attentional) resources joined with latent decrements (i.e., stress). BACKGROUND: DeLucia and Betts (2008) reported that monitoring critical signals degraded performance of a laparoscopic peg-reversal task compared with no monitoring. However, performance did not differ between displays in which critical signals were shown on split screens (less visual scanning) and separated displays (more visual scanning). We hypothesized that effects of scanning may occur after prolonged strain coping. METHOD: Using a between-subjects design, we had undergraduates perform a laparoscopic training task that induced strain coping. Then they performed a laparoscopic peg-reversal task while monitoring critical signals with a split-screen or separated display. We administered the NASA-Task Load Index (TLX) and Dundee Stress State Questionnaire (DSSQ) to assess strain coping. RESULTS: The TLX and DSSQ profiles indicated that participants engaged in strain coping. Monitoring critical signals resulted in slowed peg-reversal performance compared with no monitoring. Separated displays degraded critical-signal monitoring compared with split-screen displays. CONCLUSION: After novice observers experience strain coping, visual scanning can impair the detection of critical signals. APPLICATION: Results suggest that the design and arrangement of displays in the operating room must incorporate the attentional limitations of the surgeon. Designs that induce visual scanning may impair monitoring of critical information at least in novices. Presenting displays closely in space may be beneficial.