Master thesis presentation – Design and preliminary testing of an MR-compatible eye tracking system

Presented by Taimaz Begdjani and Fredrik Steen

Date:  Wednesday 12th of March, 10.00

Location:  Conference room “Lunnerummet”, Chalmers EDIT-building

Examiner:  Prof. Mikael Persson, Chalmers S2

Eye tracking makes it possible to track the gaze and analyse the pattern with which a person scans his/her visual field. One interesting possibility with eye tracking is the combination of this method together with other measurement systems. For this project, the other modality of interest is functional magnetic resonance imaging (fMRI), a functional neuroimaging technique. The combination of these two techniques allows for research into the correlation between brain activity and behaviour such as gaze direction, pupil dilation or eye blinks.
The aim of this thesis is to investigate the requirements of using an eye tracking system in an fMRI experiment and to design and propose a system solution that fulfills the requirements. The lead user of the eye tracking system is Smart Eye AB, a manufacturer of eye-tracking systems with commercial interest in developing a system for fMRI use.
A Functional Requirements Specification (FRS) was created that specifies the requirements for the proposed system. The bases for the FRS were from four different methods and sources: a literature study, discussions with Smart Eyes partners, analysis of a survey of potential customers, and investigations of other existing products on the market.
The proposed system consists of a camera, IR illumination, waveguide, enclosure, power source and electronics. It is encased in an RF shielded enclosure that conforms to the requirements of an MRI conditional item. The system design was performed based on the requirements, and the optical components were tested with a simple experimental design to assess compliance with the requirements. Preliminary test results indicate that our long-range one-camera system satisfies most of the requirements of the FRS, but tests with the enclosure and the waveguide needs to be done to comply with all of the requirements.