Reduced sensitivity to tactile stimuli associated with physical and mental disorders: A monozygotic twin study

Tactile sensitivity is crucial for perceiving subtle external stimuli and maintaining a high quality of life. While individual differences in tactile sensitivity are influenced by local factors, such as skin condition and nerve density, the relationships between tactile sensitivity and systemic factors, such as physical and mental health, remain unclear. This study investigated how systemic conditions are related to tactile sensitivity, excluding genetic influences, by analyzing 25 pairs of monozygotic (MZ) twins. Tactile thresholds were measured using suction stimuli on the cheek and compared with psychophysiological data from questionnaires and objective measurements. The results revealed that 18 twin pairs presented similar thresholds, indicating a genetic influence. However, in 7 twin pairs with differing thresholds, reduced tactile sensitivity was associated with greater physical and mental disorders, such as fatigue and anxiety. These findings suggest that tactile sensitivity is influenced not only by genetic factors but also by systemic health conditions that are shaped by lifestyle. Furthermore, impaired tactile sensitivity may reflect broader physical and mental health issues, making it a potential marker for preventive health interventions. This study provides insights into the complex interplay between tactile perception and systemic health, paving the way for tactile interventions aimed at enhancing the quality of life.