Psychophysical isolation of the modality responsible for detecting multimodal stimuli: a chemosensory example.

Multiple sense modalities can be stimulated conjointly by a physically complex item, such as a predator, and also by a physically solitary stimulus that acts on multiple receptor classes. As a prime example of this latter group, l-menthol from mint stimulates taste, smell, and several somatosensory submodalities. In 6 experiments that used a variety of psychometric techniques, the authors experimentally isolated the modality by which l-menthol is detected in the upper airways (the nose and mouth). Interestingly, absolute detection in both the nasal and oral cavities was based on olfaction and not stinging, cooling, or taste. These experiments illustrate how the sensory modality responsible for detecting a multimodal or multisensory stimulus can be psychophysically isolated.