Poster A53, Saturday, March 25, 5:00 – 7:00 pm, Pacific Concourse
Abnormal Speech Feedback Processing in Individuals with 16p11.2 Deletions
Carly Demopoulos1, Hardik Kothare1, Danielle Mizuiri1, Jennifer Henderson-Sabes1, Brieana Fregeau1, Jennifer Tiernagel2, Elliott Sherr1, John Houde1, Srikantan Nagarajan1; 1University of California-San Francisco, 2Simons Foundation Autism Research Initiative
Given the highly prevalent speech production deficits in children with 16p11.2 deletions, we examined the role of auditory feedback in the control of speaking in order to identify discrete points of dysfunction in the speech production system. A better understanding of these processes could lead to insights into novel targets for intervention. Two tests of sensitivity to auditory feedback during speech were collected from twelve 16p11.2 deletion and six sibling control participants. The first, called a pitch perturbation test, examined how subjects quickly changed the pitch of their voice within a trial to correct for a brief perturbation of their auditory feedback, a response known as “pitch feedback compensation”. The second test, called a speech formant adaptation test, examined how, over many trials, subjects learned to adapt to sustained vowel identity changes in their auditory feedback during vowel production. Results indicated that 16p11.2 deletion carriers showed an exaggerated pitch compensation response to unpredictable mid-vocalization pitch perturbations compared to sibling controls, t(7.45)=2.54, p=.037). In contrast, they showed reduced adaptation to sustained vowel identity changes in auditory feedback, (t(12)=3.04, p=.010). This reduced speech adaptation in the context of the strong compensation response during the pitch perturbation task indicates that while deletion carriers were able to detect and correct perceived speech errors in real time, they were unable to change their speech model in anticipation of highly predictable alterations in auditory feedback. These results suggest an over-reliance on auditory feedback and impaired predictive forward models for speaking in 16p11.2 deletions.
Topic Area: LANGUAGE: Other