|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1997 : ¥200,000 (Direct Cost : ¥200,000)
Fiscal Year 1996 : ¥200,000 (Direct Cost : ¥200,000)
Fiscal Year 1995 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Comparing the stndard concave surface with 3,4, or 5 cm in diameter and 5 or 7 mm in depth to the comparison surface with 6 cm in diameter, we obtained the PSE.As results
1.Overestimation of depth was observed in all the conditions.
2.Overestimation increased with the decrease of diameters of standard stimuli.
3.Overestimation was bigger when the surface was spherical than when the surface was oval.
4.Overestimation was the biggest when the surface was 5 or 6 mm in depth.
According to the verbal reports by the subjects, the surface with great overestimation fitted into the curvature of the fingertip, suggesting that when the surface was similar to the fingertip in curvature, overestimation of depth would increase. The hypothesis was confirmed.
To examine the effect of global shape of the stimuli on the verestimation of the depth, we used the stimuli which were enlarged by one and half times, and obtained the PSE.When the stimuli with 5 mm or 7 mm in depth were compared to the counterparts, the PSEs were about the same, whereas the PSE of the stimulus with 3 mm in depth was smaller than the counterpart.