fNIRS and Pupillometry Correlates of Attentional States

This dissertation aims to examine the localization and function of BA 10 specifically looking into its role in maintaining and switching between attentional states using functional near-infrared spectroscopy (fNIRS) and pupillometry. Previous findings from fMRI report a medial-lateral BA10 dissociation during stimulus-oriented (SO) and stimulus-independent (SI) tasks. Pupillometry has been previously used to investigate different attention states, dissociating focused, attention (on-task) trials from mind-wandered, distracted (off-task) states. However, so far there is no evidence that fNIRS hemodynamic responses (HR) and pupillary responses (PR) could be used to better characterize and identify attention states. Replacing fMRI with fNIRS, I divided SO and SI tasks into on-task and off-task groups and showed that fNIRS exhibit similar medial-lateral BA10 dissociations for SO tasks. I also showed that both HR and PR can be used to distinguish on-task SO from off-task SO groups. Finally, I explored whether fNIRS and pupillometry signals share similar biomarkers which may enhance the identification of these attention states using these measures simultaneously. This study was able to successfully characterize attention states and dissociate them on BA10 but did not confirm that simultaneous signal acquisition of these two methods would enhance the identification of attentional states.