Working Memory for Signs and Gestures

Working memory (WM) for signs and words is similar at the behavioral level, but differences emerge at the neural level. We have illuminated WM for sign language by studying behavior and neural activation in signers and nonsigners performing sign- and gesture-based n-back WM tasks. This work has shown that deaf signers have a performance advantage over hearing nonsigners on sign-based WM tasks probably due to their signing expertise. It has also shown that lexical but not phonological knowledge of sign language leads to better WM for sign language. Cross-modal plasticity driven by congenital deafness can be dissociated into sensory and cognitive components, and we have shown that deaf signers recruit the posterior portion of the superior temporal lobe for WM processing. These findings are discussed in relation to the Ease of Language Understanding (ELU) model.