The purpose of this study was to use portable electroencephalography and qualitative assessments to characterize cognitive changes associated with perceived increase in mental load and to identify markers of mental fatigue in these individuals.

The ability to focus on cognitive tasks impacts everything from our social interactions to our success in the classroom or workplace. Concussion negatively impacts the ability to focus and causes patients to experience signs of mental fatigue more quickly than those without concussion. The mechanisms behind these changes are still not well understood. 

Fifteen concussion patients and fifteen age-matched controls were recruited to participate in this study. Participants performed two, thirty-minute testing sessions spaced 1 month apart. In each session, participants performed 8 cognitive tasks eliciting varying levels of cognitive activity. Cognitive activity was quantitatively assessed using a MUSE non-invasive EEG headset. These data were compared to a perceived level of cognitive activity determined by the individual using the Klepsh et al (2017) cognitive engagement scale and mental fatigue assessed by the Mental Fatigue Scale (Johansson2014). 

The results demonstrate that frequency based EEG changes correlated with decreased ability to focus on the cognitive task and with perceived cognitive fatigue in both concussion patients and healthy controls. 

Future studies should utilize the same methods to monitor cognitive activity differences during daily functional living.