25476
Positive and Negative Affective Vocalizations in 2-Year-Olds with ASD
Objectives: Assess whether patterns of non-speech affective vocalization distinguish children in three groups: children who have an older sibling with ASD and are also diagnosed with ASD (ASD); children at high-familial risk for ASD by virtue of having an older sibling with ASD, but not currently diagnosed with ASD themselves (HR-), and children at low-familial risk for ASD with no ASD diagnosis themselves (TDC).
Methods: The Communication and Symbolic Behavior Scales (CSBS; Shumway & Wetherby, 2009) was administered to 33 2-year-olds (ASD: 9, TDC: 12, HR-: 12) participating in the Infant Brain Imaging Study (IBIS; Estes et al., 2015). Two individuals coded child non-speech vocalizations into four categories: (1) delight (laugh), (2) distress (cry, whine, fuss), (3) atypical (squeal, growl, yell, grunt), or (4) other (sound effect, uncodable); (“vegetative” vocalizations like coughs were excluded from the current analyses). For this study, we calculated the percentage of time occupied by distress and delight vocalizations relative to total amount of non-speech vocalization produced by each child.
Results: A repeated measures ANOVA with group (ASD/TDC/HR-) as a factor and affective vocalization type (delight/distress) as a repeated measure revealed a trend toward an interaction between group and type, F(2,29)=3.01, p=.065, ηp2= .17 (see Figure 1). Planned paired contrasts revealed that the ASD group produced significantly more distress than delight vocalizations (p<.05), the TDC group produced marginally more delight vocalizations than distress vocalizations (p<.08), and the HR- group produced equal amounts of each type (p=n.s.). Independent samples t-tests showed the ASD group produced a significantly higher percentage of distress vocalizations (39%) than the TDC group (14%, p<.05). In contrast, the TDC group produced a significantly higher percentage of delight vocalizations (43%) as compared to the ASD group (12%, p<.05). The HR- group was not significantly different from the other two groups on either variable.
Conclusions: Emotion regulation difficulties in ASD are common and impairing (Mazefsky et al., 2013) and dysregulation in toddlers is associated with increased parenting stress (Davis & Carter, 2008). Fine-grained identification of distress vs. delight vocalizations in children’s natural communication, demonstrated here, could serve as a way to monitor progress as clinicians and parents help children learn to regulate their emotions. We plan to code distress/delight vocalizations at 6 and 12 months as well, to understand developmental continuity and deviation in this domain (anticipated complete, May 2017).