2011 Volume 45 Issue 1 Pages 69-74
In order to investigate if it is possible to objectively assess gustatory sensation, which is one of the oral senses, we qualitatively analyzed pupillary responses using an infrared electronic pupillometer after stimulation with taste-testing preparations that elicit the taste sensations of sweet, sour, salty, and bitter. The Iriscorder^[○!R] C7364 (Hamamatsu Photonics, Shizuoka, Japan) was used to measure pupillary responses in 8 adult subjects. Taste discs^[○!R] (Sanwa Kagaku Kenkyusho, Nagoya, Japan) were used to stimulate the taste sensations of sweetness, sourness, saltiness, and bitterness. Water was used for no taste. Pupillary responses were measured before and after each taste stimulation, and the pupillary area and maximum pupillary contraction rate were analyzed. We found no significant difference in the maximum pupillary contraction rate, which is an index of parasympathetic activity, during any of the taste stimulations. However, the pupillary area, which is an index of sympathetic activity, showed significant increases on stimulations involving saltiness and bitterness. These results suggest the possibility of objectively assessing the sense of taste using an infrared electronic pupillometer.
