Feeling signs: motor encoding enhances sign language learning in hearing adults

Manual production enhances learning and recall of signs by hearing second language learners; however, the mechanisms enabling this effect are unclear. We examined whether the motor encoding (somatosensory feedback) that occurs during sign production benefits learning and whether it interacts with sign iconicity, which also enhances learning. American Sign Language (ASL) signs varying in iconicity were learned either via production (repetition) with the eyes closed or via observation without production. Signs learned via production were recalled more accurately than signs learned via observation, indicating that motor encoding from manual production enriches the representations of signs. Moreover, the effect of motor encoding interacted with iconicity, suggesting that motor encoding may particularly enhance the recall of signs low in iconicity. Together, these results reveal the importance of somatosensory feedback as a key mechanism underlying the beneficial effect of production on sign learning, demonstrating that feeling one's own signing promotes learning and recall of signs.