Assessment of goal-directed behavior and prospective memory in adult ADHD with an online 3D videogame simulating everyday tasks

The diagnosis of ADHD is based on real-life attentional-executive deficits, but they are harder to detect in adults than in children and objective quantitative measures reflecting these everyday problems are lacking. We developed an online version of EPELI 3D videogame for naturalistic and scalable assessment of goal-directed action and prospective memory in adult ADHD. In EPELI, participants perform instructed everyday chores in a virtual apartment from memory. Our pre-registered hypothesis predicted weaker EPELI performances in adult ADHD compared to controls. The sample comprised 112 adults with ADHD and 255 neurotypical controls comparable in age (mean 31, SD = 8 years), gender distribution (71% females) and educational level. Using web-browser, the participants performed EPELI and other cognitive tasks, including Conner's Continuous Performance Test (CPT). They also filled out questionnaires probing everyday executive performance and kept a 5-day diary of everyday prospective memory errors. Self-reported strategy use in the EPELI game was also examined. The ADHD participants' self-ratings indicated clearly more everyday executive problems than in the controls. Differences in the EPELI game were mostly seen in the ADHD participants' higher rates of task-irrelevant actions. Gender differences and a group × gender interaction was found in the number of correctly performed tasks, indicating poorer performance particularly in ADHD males. Discriminant validity of EPELI was similar to CPT. Strategy use strongly predicted EPELI performance in both groups. The results demonstrate the feasibility of EPELI for online assessment and highlight the role of impulsivity as a distinctive everyday life problem in adult ADHD.

Assessment of goal-directed behavior with the 3D videogame EPELI: Psychometric features in a web-based adult sample

EPELI (Executive Performance in Everyday LIving) is a recently developed gaming tool for objective assessment of goal-directed behavior and prospective memory (PM) in everyday contexts. This pre-registered study examined psychometric features of a new EPELI adult online version, modified from the original child version and further developed for self-administered web-based testing at home. A sample of 255 healthy adults completed EPELI where their task was to perform household chores instructed by a virtual character. The participants also filled out PM-related questionnaires and a diary and performed two conventional PM tasks and an intelligence test. We expected that the more "life-like" EPELI task would show stronger associations with conventional PM questionnaires and diary-based everyday PM reports than traditional PM tasks would do. This hypothesis did not receive support. Although EPELI was rated as more similar to everyday tasks, performance in it was not associated with the questionnaires and the diary. However, there were associations between time-monitoring behavior in EPELI and the traditional PM tasks. Taken together, online adult-EPELI was found to be a reliable method with high ecological face validity, but its convergent validity requires further research.

EPELI: a novel virtual reality task for the assessment of goal-directed behavior in real-life contexts

A recently developed virtual reality task, EPELI (Executive Performance in Everyday LIving), quantifies goal-directed behavior in naturalistic conditions. Participants navigate a virtual apartment, performing household chores given by a virtual character. EPELI aims to tap attention, executive function, and prospective memory. To ensure its applicability to further research and clinical work and to study its relationship to relevant background factors, we examined several key properties of EPELI in 77 typically developing 9–13-year-old children. These included EPELI’s internal consistency, age and gender differences, sensitivity to gaming experience, head-mounted display (HMD) type, and verbal recall ability, as well as its relationships with parent-rated everyday executive problems. Of the eight EPELI measures, the following six showed acceptable internal consistency: task and navigation efficacy, number of correctly performed tasks and overall actions, time monitoring, and controller movement. Some measures were associated with age, gender, or verbal encoding ability. Moreover, EPELI performance was associated with parent-rated everyday executive problems. There were no significant associations of gaming background, task familiarity, or HMD type with the EPELI measures. These results attest to the reliability and ecological validity of this new virtual reality tool for the assessment of attention, executive functions, and prospective memory in children.

Between the Scenes

We constantly move our eyes to new information while inspecting a scene, but these patterns of eye movements change based on the task and goals of the observer. Inhibition of return (IOR) may facilitate visual search by reducing the likelihood of revisiting previously attended locations. However, IOR may present in any visual task, or it may be search-specific. We investigated the presence of IOR in foraging, memorization, change detection, and two versions of visual search. One version of search used a static search array that remained stable throughout the trial, but the second used a scene flickering paradigm similar to the change detection task. IOR was observed in both versions of visual search, memorization, and foraging, but not in change detection. Visual search and change detection both had temporal nonscene components, and we observed that IOR could be maintained despite the scene removal but only for search. Although IOR is maintained in scene coordinates, short disruptions to this scene are insufficient to completely remove the inhibitory tags. Finally, we compare return saccades in trials without a probe and observe fewer return saccades in tasks for which IOR was observed, providing further evidence that IOR might serve as a novelty drive.

Temporal Limitations of the Standard Leaky Integrate and Fire Model

Itti and Koch's Saliency Model has been used extensively to simulate fixation selection in a variety of tasks from visual search to simple reaction times. Although the Saliency Model has been tested for its spatial prediction of fixations in visual salience, it has not been well tested for their temporal accuracy. Visual tasks, like search, invariably result in a positively skewed distribution of saccadic reaction times over large numbers of samples, yet we show that the leaky integrate and fire (LIF) neuronal model included in the classic implementation of the model tends to produce a distribution shifted to shorter fixations (in comparison with human data). Further, while parameter optimization using a genetic algorithm and Nelder-Mead method does improve the fit of the resulting distribution, it is still unable to match temporal distributions of human responses in a visual task. Analysis of times for individual images reveal that the LIF algorithm produces initial fixation durations that are fixed instead of a sample from a distribution (as in the human case). Only by aggregating responses over many input images do they result in a distribution, although the form of this distribution still depends on the input images used to create it and not on internal model variability.