Pupillometry as an outcome measure
Our eyes can actually help us understand those cognitive operations. Pupillometry,
the measurement of our pupil size, has a long history of application as an outcome measure of cognitive processing load in research. For example, the pupils become larger when a person invest more effort in listening. We refer to this as listening effort.
The dilation of the pupil when doing a task is associated with Autonomic Nervous Systems (ANS) activity, more specifically with the sympathetic and parasympathetic nervous branch of the ANS. See the dilation of the pupil in this video.
Within the field of cognitive hearing science, it has been demonstrated that pupil dilation can index the cognitive processing load and effort mobilization involved in speech communication.
Within our group, we use pupillometry to learn more about effort mobilization and fatigue in people with hearing loss. Our recent work demonstrated that pupillometry can be applied to identify a benefit of the hearing-aid signal processing on listening effort.