Tactile Adaptation to Orientation Produces a Robust Tilt Aftereffect and Exhibits Crossmodal Transfer When Tested in Vision

Orientation processing is one of the most fundamental functions in both visual and somatosensory perception. Converging findings suggest that orientation processing in both modalities is closely linked: somatosensory neurons share a similar orientation organisation as visual neurons, and the visual cortex has been found to be heavily involved in tactile orientation perception. The tilt aftereffect (TAE) is a demonstration of orientation adaptation and is used widely in behavioural experiments to investigate orientation mechanisms in vision. By testing the classic TAE paradigm in both tactile and crossmodal orientation tasks between vision and touch we were able to show that tactile perception of orientation shows a very robust TAE, similar to its visual counterpart. We further show that orientation adaptation in touch transfers to produce a TAE when tested in vision, but not vice versa. We also observed a similar asymmetricity in the intramodal serial dependence effect within the test sequence. These findings provide concrete evidence that vision and touch engage a similar orientation processing mechanism, but the asymmetry in the crossmodal transfer of TAE and serial dependence provides more insights into the underlying mechanism of this link.