Unpleasant mood is linked to local processing in haptics.

Happy and sad moods promote global and local visual processing, respectively. However, it is unclear whether mood also affects the processing level in haptics. Here, we used classical music to induce happy and sad moods in blindfolded participants before they scanned printed, flat 2D embossed configurations with their fingers. We also included a neutral group that did not listen to any music. Global shapes were triangles, circles, or squares (33 mm) composed of smaller local relief shapes (3 mm): either triangles, circles, or squares. Participants explored a probe stimulus with identical local and global shapes, and two comparison stimuli, matching the probe in local or global shape. They reported which comparison stimulus appeared more similar to the probe. In the "sad" group, participants chose the locally matching comparison more frequently than in the "happy" and "neutral" groups, suggesting that unpleasant mood can influence spatial preferences in haptic shape matching. Overall, participants tended to prefer global matches, indicating that under these specific conditions, global-level information may be relatively more prominent in touch.