University of Houston
Department of Computer Science

In partial fulfillment of the Requirements for the Degree of
Doctor of Philosophy

ZHEN ZHU
will present his dissertation proposal

Applications of Thermal Imaging in Psychology and Medicine

Abstract

This research effort focuses on quantifying stress and detecting abnormal breathing patterns. The former is embedded within a psychological framework with applications in software usability and lie detection in high-stakes interrogations. The latter is embedded within a medical framework with applications in sleep studies. Stress is a ubiquitous psycho-physiological response and comes in two varieties: instantaneous and sustained. Instantaneous stress arises in response to startling stimuli, perceived as threats. It is manifested by sharp changes in peripheral blood distribution towards muscle-skeletal tissue, which dissipate very quickly. Sustained stress arises in response to mental processes, builds slowly and lasts for some time. Nowadays, as most people do office work using computers, sustained stress arises naturally as part of human-computer interaction. This research has established an association between sustained stress and increased blood flow in the supra-orbital vessel that feeds the corrugator muscle. Furthermore, it developed a measurement method based on thermal imaging that is contact-free, passive, and highly automated. Therefore, mental stress can now be quantified in the most transparent manner. First application of this technology was the quantification of reading load, which led to the selection of preferred fonts for the new Windows operating system, a project that was run collaboratively with Microsoft Research. This opens the way for a multitude of software usability applications never even imagined before. At a different level, this work facilitates a deeper understanding of the nature of mental stress and its correlation to primal forms of communication through facial muscle action - a beautiful physiological verification of the psychological observation theories of Paul Ekman. In addition, this research has developed methods to detect deceptive behavior by measuring both instantaneous and sustained occurrences of stress in high-stakes interrogations. Since these methods are based on thermal imaging measurements of facial physiology, they open the way for on-the-fly application of lie detection technology in control checkpoints. The implications of this application to homeland security cannot be underestimated. Finally, a branch of this research aims to revolutionize sleep studies by removing some or all of the sensor cabling from the patient. The focus is on detecting abnormal breathing patterns (e.g., sleep apnea) using imaging-based measurement technology developed earlier by Pavlidis et al. In preparation of human experiments, a specialized tracker has been developed to make the application of the imaging measurement method feasible in a realistic set-up.

Date: May 4^th, 2006
Time: 9:00AM
Place: PGH 218

Faculty, students, and the general public are invited.
Advisor: Ioannis Pavlidis