Motions of visual images projected on the retina (referred to as retinal slips) are essential for provoking vection (illusion of self-motion) and visually induced motion sickness (VIMS) (Brandt, 1973). These projected image motions can be classified into: (i) peripheral retinal slip (PRS) and (ii) foveal retinal slip (FRS). Both PRS and FRS are modulated by eye motion (EM). Eye motion (EM) has also been found to play a crucial role in causing visually induced motion sickness (VIMS) (Ebenholtz et al., 1994). In past studies, effects of EM were confounded with FRS or PRS. Empirical study on the isolated effects of EM, FRS and PRS on VIMS could not be found.

This thesis reports a series of studies evaluating the isolated effects of EM velocity (EMv), PRS velocity (PRSv) and FRS ve...[ Read more ]

Motions of visual images projected on the retina (referred to as retinal slips) are essential for provoking vection (illusion of self-motion) and visually induced motion sickness (VIMS) (Brandt, 1973). These projected image motions can be classified into: (i) peripheral retinal slip (PRS) and (ii) foveal retinal slip (FRS). Both PRS and FRS are modulated by eye motion (EM). Eye motion (EM) has also been found to play a crucial role in causing visually induced motion sickness (VIMS) (Ebenholtz et al., 1994). In past studies, effects of EM were confounded with FRS or PRS. Empirical study on the isolated effects of EM, FRS and PRS on VIMS could not be found.

This thesis reports a series of studies evaluating the isolated effects of EM velocity (EMv), PRS velocity (PRSv) and FRS velocity (FRSv) on VIMS. In Experiment one, effects of EMv and FRSv on VIMS were evaluated under controlled PRSv. In Experiment two, effects of PRSv on VIMS under controlled EMv (40dps) was examined. Results showed that (i) increasing FRSv from 0dps to 15dps during occurrence of EM significantly increased VIMS (p<0.005); (ii) reduction of EMv during occurrence of FRS significantly reduced VIMS (p<0.01); and (iii) increasing PRSv from 10dps to 60dps increases the mean value of VIMS but the effect was not significant when EMv was controlled at 40dps. Experiments three and four studied the role of EM on VIMS among computer game players. Results showed that (i) reducing EMv could reduce VIMS during passive watching; (ii) active playing and passive watching did not result in different EMv; and (iii) the use of an eye fixation marker did not reduce EMv during active game playing.

The last part of the thesis focuses on modeling the relative contributions of EMv, PRSv and FRSv on VIMS. Results of regression analyses showed that all three predictor variables had significant main effects towards VIMS and the model R-sq was 97%. Further conclusion and discussion are presented in this thesis.