IEEE SMC Hiroshima Chapter Acta Medica Okayama 1883-3977 2009 1 2009 Effects of Image and Layered Structure on Web Search Performance -Evaluation on the Basis of Movement Distance of Mouse Pointer- 342 347 EN Atsuo Murata Makoto Moriwaka Takehito Hayami The aim of this paper was to explore the effects of image addition and layered structure on Web search performance on the basis of the search time and the movement trajectory of mouse pointer. The difference of search characteristics between young and older adults was also examined. Older adults tended to take more time to search for the linked item especially when the layered structure was deep. For the deep layered structure, both young and older adults allocate more time to think which items should be selected than to operate a mouse. For all participants, less mouse movement was observed for the image-based link condition than for the character-based link condition. This tendency was more remarkable for older adults. Moreover, it was clarified that more mouse movement was observed with the increase of the number of hyperlinks per Web page. When the layered structure was shallow, the following difference of mouse operation characteristics between young and older adults was observed: Older adults made an attempt to locate the search item while moving a mouse simultaneously. On the other hand, young adults began to move a mouse after locating the search item. No potential conflict of interest relevant to this article was reported.

IEEE SMC Hiroshima Chapter Acta Medica Okayama 1883-3977 2009 1 2009 Visual information processing characteristics of drivers in prediction of dangerous situation - Comparison among novice, expert and non-licensed person - 254 257 EN Atsuo Murata Takehito Hayami Makoto Moriwaka The aim of this study was to examine the difference of visual information processing in KYT (Kiken Yochi Training) among novice, expert and non-licensed persons. In KYT tasks, participants were required to search for a potentially dangerous part using a static image under driving situations. The location of fixation point and the time series change of eye gaze were measured using an eye camera. In order to detect the difference of visual information processing among three groups above, an important area that the participants must pay attention to with the highest priority was set for each static image. The time until the eye gaze fixates to the important area, and the ratio of the fixation time to the total search time were detected. Using these measures, the difference of visual information processing among three groups was clarified. Moreover, for novice and non-licensed participants, it was also explored whether a lecture related to KYT would improve the efficiency of visual information processing. The time until the eye gaze fixates to the important area was longer for the non-licensed participants than for the experienced participants. The learning effect by means of a KYT lecture was also observed. No potential conflict of interest relevant to this article was reported.

IEEE SMC Hiroshima Chapter Acta Medica Okayama 1883-3977 2009 1 2009 Effects of State of Eye Movements before Saccade on Efficiency of Response to Stimulus - Comparison of Search Efficiency between Fixation and Smooth Pursuit Situations - 182 185 EN Atsuo Murata Takehito Hayami Makoto Moriwaka In this study, how the state of eye movement before saccade affected the response to a stimulus was explored. The state of eye movement before saccade was either smooth pursuit or fixation. The smooth pursuit was carried out both clockwise and counter-clockwise. Using an eye-tracking system, the eye movement during the experimental task was monitored. The response time to a stimulus was measured. On the basis of the eye movement data (coordinate), the eye movement velocity, the eye movement acceleration, and the latency of eye movement were obtained. When smooth pursuit was carried out before saccade, the response to a stimulus which appears as a result of saccade was faster. More concretely, the response time of smooth pursuit condition was faster than that of fixation condition. The latency of the smooth pursuit condition tended to be faster than that of the fixation condition. Some implications for the application of the results to the traffic safety or automotive ergonomics were given. No potential conflict of interest relevant to this article was reported.