Pupillometry as an index for cognitive processing in behavioral variant FrontoTemporal Dementia: a series of case studies

ABSTRACT

We investigated whether pupil size can variate with the intensity of cognitive processing in patients with behavioral-variant-Frontotemporal-Dementia (bvFTD). We invited five bvFTD participants and 21 controls to perform forward spans and backward spans, and, in a control condition, to count aloud. We recorded pupil activity using eye-tracking-glasses during the spans and control condition. Analysis demonstrated larger pupil sizes during backward spans than during forward spans, and larger pupil sizes during forward spans than during counting in both bvFTD and control participants. These findings demonstrate how increased cognitive load triggers increased pupil size and how this connection is maintained in bvFTD.

KEYWORDS:

• Behavioral variant FrontoTemporal Dementia
• cognitive load
• FrontoTemporal Dementia
• pupillometry
• spans

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

Raw data can be shared under reasonable request by email to the correspondent author

Additional information

Funding

The author DK was supported entirely by the Intramural Research Program of the National Institute on Aging, NIH.