Osmotexia and the somatosensory dimension of smell: toward a fourth axis in chemosensory evaluation.

BACKGROUND

The evaluation of olfaction is classically based on three psychophysical axes: threshold, discrimination, and identification. However, these do not fully reflect the multisensory nature of odour perception. It is well established that numerous odours can activate the trigeminal system, thereby generating somatosensory sensations such as texture, density, or temperature. This is a dimension that is currently absent from clinical evaluation models.

AIMS/

OBJECTIVES

The present study introduces and conceptualises osmotexia as the ability to experience odours in terms of internal texture. It proposes osmotexia as a fourth axis in chemosensory evaluation, with diagnostic, rehabilitative and perceptual relevance.

METHODS

An integrative theoretical framework was developed, based on neurophysiological, psychophysical and linguistic evidence on olfactory-trigeminal interaction. A structured model is predicated on clinical observations and analyses of olfactory perception maps. The model incorporates a Likert scale of tactile descriptors and the Osmothexic Wheel, which is organised into perceptual texture categories.

RESULTS

Osmotexia facilitates the systematisation of tactile descriptors frequently reported by patients but not captured by standard tests, thus revealing diversified perceptual profiles in subjects with similar olfactory scores. This approach facilitates the characterisation of qualitative smell disorders, the monitoring of olfactory rehabilitation, and the expansion of the clinical language of smell.