Semester of Graduation

Fall 2021


Master of Arts (MA)



Document Type



Co-speech gesture is an important part of human communication and aids in comprehension, learning, and memory. The addition of iconic gestures to speech has been shown in prior work to enhance memory for the speech. However, it remains unclear as to whether this benefit requires gestures to be meaningful, or, conversely, if any attentionally-engaging gesture will enhance memory. In the current study, we tested two theories to explain the mnemonic benefits of co-speech gesture: Dual Coding Theory, which attributes these benefits to multimodal encoding and enhanced imageability, and Attentional Highlighting Theory, which posits that gestures draw more attention to concurrent speech. We recorded continuous EEG data while participants watched videos of an actor reciting novel word pairs, and tested the effects of adding of an iconic or a nonsense gesture to the first word of each pair on mental imagery, item memory (memory for gestured words), or associative memory (memory for entire pairs). We found that iconic gestures, but not nonsense gestures, enhanced subjective ratings of imageability and improved item memory. However, these benefits did not extend to pair memory, despite an overall association between perceived imageability and pair memory. ERP analyses suggested that the presence of a gesture concurrently with the first word in each pair may have detracted from the processing of the second words, thus limiting the benefits of iconic gestures to item memory. Overall, these results provide tentative support for a dual-coding based explanation of the mnemonic benefits of co-speech gesture.

Committee Chair

Dr. Heather Lucas

Available for download on Wednesday, October 12, 2022