The role of neck afferents in subjective orientation in the visual and tactile sensory modalities

We studied the influence of neck afferents on the perception of orientation . In Experiment 1, we investigated the effect of head till on the subjectiv e vertical in both the visual and tactile modalities. The results showed th at head tilt triggers an Aubert effect in the visual modality and a Muiler effect in the tactile modality. Significant positive correlations between t he two adjustment modalities were restricted to head tilt to the left. In E xperiment 2, we investigated the role of neck afferents on tactile orientat ion in seated and supine positions. The results showed that, in the supine position, the tactile E-effect was twice as large as in the seated position . These experiments confirm that tactile perception of orientation is affec ted by neck afferents, and show that the influence of neck afferents is lim ited by relevant gravitational cues.