Background: Mild cognitive impairment (MCI) is a condition that entails a slight yet noticeable decline in cognition that exceeds normal age-related changes. Older adults living with MCI have a higher chance of progressing to dementia, which warrants regular cognitive follow-up at memory clinics. However, due to time and resource constraints, this follow-up is conducted at separate moments in time with large intervals in between. Casual games, embedded into the daily life of older adults, may prove to be a less resource-intensive medium that yields continuous and rich data on a patient’s cognition. Objective: To explore whether digital biomarkers of cognitive performance, found in the casual card game Klondike Solitaire, can be used to train machine-learning models to discern games played by older adults living with MCI from their healthy counterparts. Methods: Digital biomarkers of cognitive performance were captured from 23 healthy older adults and 23 older adults living with MCI, each playing 3 games of Solitaire with 3 different deck shuffles. These 3 deck shuffles were identical for each participant. Using a supervised stratified, 5-fold, cross-validated, machine-learning procedure, 19 different models were trained and optimized for F1 score. Results: The 3 best performing models, an Extra Trees model, a Gradient Boosting model, and a Nu-Support Vector Model, had a cross-validated F1 training score on the validation set of ≥0.792. The F1 score and AUC of the test set were, respectively, >0.811 and >0.877 for each of these models. These results indicate psychometric properties comparative to common cognitive screening tests. Conclusion: The results suggest that commercial card games, not developed to address specific mental processes, may be used for measuring cognition. The digital biomarkers derived from Klondike Solitaire show promise and may prove useful to fill the current blind spot between consultations.

Background Mild cognitive impairment (MCI), the intermediate cognitive status between normal cognitive decline and pathological decline, is an important clinical construct for signaling possible prodromes of dementia. However, this condition is underdiagnosed. To assist monitoring and screening, digital biomarkers derived from commercial off-the-shelf video games may be of interest. These games maintain player engagement over a longer period of time and support longitudinal measurements of cognitive performance. Objective This paper aims to explore how the player actions of Klondike Solitaire relate to cognitive functions and to what extent the digital biomarkers derived from these player actions are indicative of MCI. Methods First, 11 experts in the domain of cognitive impairments were asked to correlate 21 player actions to 11 cognitive functions. Expert agreement was verified through intraclass correlation, based on a 2-way, fully crossed design with type consistency. On the basis of these player actions, 23 potential digital biomarkers of performance for Klondike Solitaire were defined. Next, 23 healthy participants and 23 participants living with MCI were asked to play 3 rounds of Klondike Solitaire, which took 17 minutes on average to complete. A generalized linear mixed model analysis was conducted to explore the differences in digital biomarkers between the healthy participants and those living with MCI, while controlling for age, tablet experience, and Klondike Solitaire experience. Results All intraclass correlations for player actions and cognitive functions scored higher than 0.75, indicating good to excellent reliability. Furthermore, all player actions had, according to the experts, at least one cognitive function that was on average moderately to strongly correlated to a cognitive function. Of the 23 potential digital biomarkers, 12 (52%) were revealed by the generalized linear mixed model analysis to have sizeable effects and significance levels. The analysis indicates sensitivity of the derived digital biomarkers to MCI. Conclusions Commercial off-the-shelf games such as digital card games show potential as a complementary tool for screening and monitoring cognition. Trial Registration ClinicalTrials.gov NCT02971124; https://clinicaltrials.gov/ct2/show/NCT02971124

Individuals suffering from cognitive impairment require early diagnosis and frequent follow-up. However, as the healthcare system is overburdened, contact moments with patients are sparse. Digital biomarkers are a form of non-intrusive continuous measurements of cognitive health, found in daily activities. They can help in the diagnosis and follow-up of cognitive impairments. Playing videogames is an example of these daily activities which requires cognitive effort, hence carrying cognitive information. However, extracting these digital biomarkers from commercial games tends to be challenging. To this end, we explored capturing digital biomarkers from existing card games through computer vision. A toolkit was designed for the standard Microsoft Solitaire Collection, allowing for unobtrusively measuring digital biomarkers. Results show that this technique allows for real-time processing of cognitive digital biomarkers. Digital biomarkers were captured from 44 participants in three age groups. An initial data exploration supports the promise of these digital biomarkers as bearers of cognitive information. Differences were seen amongst the age groups caused by agerelated cognitive changes. These results suggest that digital biomarkers in commercial games can be used for unobtrusive long-term cognitive monitoring with minimal burden on patient and physician, potentially leading to a more complete, clear cognitive profile.

This paper investigates whether Klondike Solitaire can be used as an assessment tool for mild cognitive impairment (MCI). It does so by providing a structured analysis and mapping player actions to cognitive functions. For Klondike Solitaire, 22 player actions were defined and mapped to 10 cognitive functions by 3 health professionals in the field of MCI. The results indicate that Attention, Executive Function, Object Recognition, Abstraction and Memory can be assessed through gameplay of Solitaire. Healthcare professionals confirmed that this can potentially be valuable, as it can screen for cognitive impairments longitudinally, in a nonintrusive way, without practice effects.

BACKGROUND Mild Cognitive Impairment, the intermediate cognitive status between healthy cognitive decline and pathological decline, is an important clinical construct for signaling possible prodromes of dementia. Unfortunately, there is an underdetection of this condition. To provide monitoring and screening, commercial off-the-shelf video games may be of interest. They maintain player engagement over a longer period of time and support longitudinal measurements of cognitive performance. OBJECTIVE This paper aims to explore how player actions of Klondike Solitaire relate to cognitive functions and to which extent they are indicative of Mild Cognitive Impairment. METHODS Eleven experts in the domain of cognitive impairments were asked to correlate 21 player actions to eleven cognitive functions. Expert agreement was verified through intraclass correlation, based on a two-way fully crossed design with type consistency. RESULTS All intraclass correlations for player actions and cognitive function scored above 0.75, indicating good to excellent reliability. Further scrutinizing of the results revealed that all player actions had at least one cognitive function which was on average moderately to strongly correlated to a cognitive function. Similarly, each cognitive function had at least one player action which was on average moderately to strongly correlated. Similarities and patterns were found amongst player actions, providing insight into the mechanics of Klondike Solitaire gameplay. CONCLUSIONS Together, these results suggest that Klondike Solitaire has potential as a complementary tool for screening and monitoring cognition, warranting further research which analyses Klondike Solitaire gameplay data of older adults with mild cognitive impairment.