Cognitive assessments

The MoCA is a global cognitive screen for patients with mild cognitive impairment that measures visuospatial, executive function, language, attention, concentration and working memory. Visuospatial abilities are assessed through a task where participants are required to draw a clock and a cube. Areas of executive functioning are assessed using the Trail making B task, a fluency task, and a verbal abstraction task. Attention, concentration, and working memory are evaluated through a sustained attention task, serial subtraction task, and digit forwards and backwards task. Language is assessed through a naming task, fluency task, and complex sentences. Knowledge of place and orientation is also tested (Nasreddine et al., 2005). Thirty is the highest possible score on the MoCA, although the definition of MoCA-indicated cognitive impairment has varied across studies (Lim & Loo, 2018). In addition to the total score, the Delayed Recall section was also considered for analysis.

We used the mental processing task, Serial 3s, to assess working memory and mental status. Participants are asked to perform serial subtractions by 3s from a random number ranging from 20–100. Participants were given 15 seconds to perform subtractions. Three trials were administered, and number of errors and correct subtractions were averaged from each of the three trials. Percent correct was calculated from the total number of responses given.