Pupillometric measurement of cognitive workload

Objective This novel preliminary study sought to capture dynamic changes in heart rate variability (HRV) as a proxy for cognitive workload among perfusionists while operating the cardiopulmonary bypass (CPB) pump during real-life cardiac surgery. Background Estimations of operators’ cognitive workload states in naturalistic settings have been derived using noninvasive psychophysiological measures. Effective CPB pump operation by perfusionists is critical in maintaining the patient’s homeostasis during open-heart surgery. Investigation into dynamic cognitive workload fluctuations, and their relationship with performance, is lacking in the literature. Method HRV and self-reported cognitive workload were collected from three Board-certified cardiac perfusionists ( N = 23 cases). Five HRV components were analyzed in consecutive nonoverlapping 1-min windows from skin incision through sternal closure. Cases were annotated according to predetermined phases: prebypass, three phases during bypass, and postbypass. Values from all 1min time windows within each phase were averaged. Results Cognitive workload was at its highest during the time between initiating bypass and clamping the aorta (preclamp phase during bypass), and decreased over the course of the bypass period. Conclusion We identified dynamic, temporal fluctuations in HRV among perfusionists during cardiac surgery corresponding to subjective reports of cognitive workload. Not only does cognitive workload differ for perfusionists during bypass compared with pre- and postbypass phases, but differences in HRV were also detected within the three bypass phases. Application These preliminary findings suggest the preclamp phase of CPB pump interaction corresponds to higher cognitive workload, which may point to an area warranting further exploration using passive measurement.

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Sparse coding classification and cepstral singular value for cognitive workload estimation

Computers & Electrical Engineering ◽

10.1016/j.compeleceng.2021.107031 ◽

2021 ◽

Vol 91 ◽

pp. 107031

Author(s):

Peyvand Ghaderyan ◽

Ataollah Abbasi

Keyword(s):

Sparse Coding ◽

Singular Value ◽

Cognitive Workload

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Effect of Distracting Background Speech in an Auditory Brain–Computer Interface

Brain Sciences ◽

10.3390/brainsci11010039 ◽

2021 ◽

Vol 11 (1) ◽

pp. 39

Author(s):

Álvaro Fernández-Rodríguez ◽

Ricardo Ron-Angevin ◽

Ernesto J. Sanz-Arigita ◽

Antoine Parize ◽

Juliette Esquirol ◽

...

Keyword(s):

Brain Computer Interface ◽

Event Related Potential ◽

Computer Interface ◽

Cognitive Workload ◽

Auditory Event ◽

Shared Attention ◽

Attentional Condition ◽

Different Types ◽

The Impact ◽

Auditory Bci

Studies so far have analyzed the effect of distractor stimuli in different types of brain–computer interface (BCI). However, the effect of a background speech has not been studied using an auditory event-related potential (ERP-BCI), a convenient option when the visual path cannot be adopted by users. Thus, the aim of the present work is to examine the impact of a background speech on selection performance and user workload in auditory BCI systems. Eleven participants tested three conditions: (i) auditory BCI control condition, (ii) auditory BCI with a background speech to ignore (non-attentional condition), and (iii) auditory BCI while the user has to pay attention to the background speech (attentional condition). The results demonstrated that, despite no significant differences in performance, shared attention to auditory BCI and background speech required a higher cognitive workload. In addition, the P300 target stimuli in the non-attentional condition were significantly higher than those in the attentional condition for several channels. The non-attentional condition was the only condition that showed significant differences in the amplitude of the P300 between target and non-target stimuli. The present study indicates that background speech, especially when it is attended to, is an important interference that should be avoided while using an auditory BCI.

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