Electrogustometry: Spatial Threshold Variations

Abstract

The distribution of the fungiform papillie of the tongue is known to be uneven. In order to demonstrate similar spatial variations of the sensitivity to electric taste stimulation, thresholds were registered in 10 normal subjects at six different points on the tongue surface. The sensitivity was found to be greatest along the edge of the tongue, usually with a minimum threshold at the tip of the tongue. The individual differences were rather pronounced and moderate threshold differences between symmetrical points on the two sides were found in a few cases. As the stimulating electrode cannot be applied repeatedly to exactly the same point, the spatial threshold variations may influence the results of clinical taste examinations. In order to ensure selective stimulation of the two sides, a point on the edge of the tongue, 1¹/₂ cm from the midline is usually preferred for clinical threshold determinations. The threshold at this point was found to be representative and close to the minimum threshold in all subjects.