A pilot study on pupillary and cardiovascular changes induced by stereoscopic video movies.
BACKGROUND
Taking advantage of developed image technology, it is expected that image presentation would be utilized to promote health in the field of medical care and public health. To accumulate knowledge on biomedical effects induced by image presentation, an essential prerequisite for these purposes, studies on autonomic responses in more than one physiological system would be necessary. In this study, changes in parameters of the pupillary light reflex and cardiovascular reflex evoked by motion pictures were examined, which would be utilized to evaluate the effects of images, and to avoid side effects.


METHODS
Three stereoscopic video movies with different properties were field-sequentially rear-projected through two LCD projectors on an 80-inch screen. Seven healthy young subjects watched movies in a dark room. Pupillary parameters were measured before and after presentation of movies by an infrared pupillometer. ECG and radial blood pressure were continuously monitored. The maximum cross-correlation coefficient between heart rate and blood pressure, rho max, was used as an index to evaluate changes in the cardiovascular reflex.


RESULTS
Parameters of pupillary and cardiovascular reflexes changed differently after subjects watched three different video movies. Amplitudes of the pupillary light reflex, CR, increased when subjects watched two CG movies (movies A and D), while they did not change after watching a movie with the real scenery (movie R). The rho max was significantly larger after presentation of the movie D. Scores of the questionnaire for subjective evaluation of physical condition increased after presentation of all movies, but their relationship with changes in CR and rho max was different in three movies. Possible causes of these biomedical differences are discussed.


CONCLUSIONS
The autonomic responses were effective to monitor biomedical effects induced by image presentation. Further accumulation of data on multiple autonomic functions would contribute to develop the tools which evaluate the effects of image presentation to select applicable procedures and to avoid side effects in the medical care and rehabilitation.
Oyamada
Hiroshi
H
Division of Integrated Physiology, Niigata University Graduate School for Medical and Dental Sciences, Asahi-machi1, Niigata, 951-8510, Japan. theta@qg7.so-net.ne.jp
Iijima
Atsuhiko
A
Tanaka
Akira
A
Ukai
Kazuhiko
K
Toda
Haruo
H
Sugita
Norihiro
N
Yoshizawa
Makoto
M
Bando
Takehiko
T
D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009040:Motion Pictures; D010775:Photic Stimulation / Q000379:methods*; D010865:Pilot Projects; D011680:Pupil / Q000502:physiology*; D014741:Video Recording