Effects of emotion on the acoustic parameters in adults who stutter: An exploratory study

Effects of Positive and Negative Emotions on Picture Naming for People With Mild-to-Moderate Aphasia: A Preliminary Investigation

PURPOSE

The purpose of the study is to investigate how emotional arousal and valence affect confrontational naming accuracy and response time (RT) in people with mild-to-moderate aphasia compared with adults without aphasia. We hypothesized that negative and positive emotions would facilitate naming for people with aphasia (PWA) but lead to slower responses for adults with no aphasia.

METHOD

Eight participants with mild-to-moderate aphasia, 15 older adults (OAs), and 17 young adults (YAs) completed a confrontational naming task across three conditions (positive, negative, and neutral) in an ABA (where A = neutral and B = negative) case series design. Immediately following each naming condition, participants self-reported their perceived arousal and pleasure. Accuracy and RT were measured and compared.

RESULTS

As expected, PWA performed significantly less accurately and with longer RTs than both YA and OA groups across all conditions. However, opposite our hypothesis for the aphasia group, the negative condition resulted in decreased accuracy for the aphasia and the OA group and increased RT across all groups. No statistically significant differences were found between the positive and any other condition. Participants with aphasia who demonstrated an effect in the negative condition were observed to produce a larger proportion of semantically related errors than any other error types.

CONCLUSIONS

Findings suggest that strong negative emotions can interfere with semantic-lexical processing by diverting attentional resources to emotion regulation. Both clinicians and researchers should be aware of the potential influence of negative stimuli and negative emotional states on language performance for PWA, and these effects should be disentangled in future research. Further research should also be conducted with a larger number of participants with aphasia across a broader range of severity to replicate and extend findings.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19119356.

Voice onset time and formant onset frequencies in Arabic stuttered speech

Neuromuscular models of stuttering consider that making transitions between phones results in inappropriate temporal arrangements of articulators in people who stutter (PWS). Using this framework, the current study examined the acoustic productions of two fine-grained phonetic features: voice onset time (VOT) and second formant (F2). The hypotheses were that PWS should differ from fluent persons (FP) in VOT duration and F2 onset frequency as a result of the transition deficit for environments with complex phonetic features such as Arabic emphatics. Ten adolescent PWS and 10 adolescent FPs participated in the study. They read and memorized four monosyllabic plain-emphatic words silently. Data were analyzed by Repeated Measures ANOVAs. The positive and negative VOT durations of/t/vs./tˁ/and/d/vs./dˁ/and F2 onset frequency were measured acoustically. Results showed that stuttering was significantly affected by emphatic consonants. PWS had atypical VOT durations and F2 values. Findings are consistent with the atypicality of VOT and F2 reported for English-speaking PWS. This atypicality is realized differently in Arabic depending on the articulatory complexity and cognitive load of the sound.

Effects of Social Stress on Autonomic, Behavioral, and Acoustic Parameters in Adults Who Stutter

Purpose The purpose of this study was to assess changes in autonomic, behavioral, and acoustic measures in response to social stress in adults who stutter (AWS) compared to adults who do not stutter (ANS). Method Participants completed the State-Trait Anxiety Inventory ( Speilberger, Gorsuch, Luschene, Vagg, & Jacobs, 1983 ). In order to provoke social stress, participants were required to complete a modified version of the Trier Social Stress Test (TSST-M, Kirschbaum, Pirke, & Hellhammer, 1993 ), which included completing a nonword reading task and then preparing and delivering a speech to what was perceived as a group of professionals trained in public speaking. Autonomic nervous system changes were assessed by measuring skin conductance levels, heart rate, and respiratory sinus arrhythmia (RSA). Behavioral changes during speech production were measured in errors, percentage of syllable stuttered, percentage of other disfluencies, and speaking rate. Acoustic changes were measured using 2nd formant frequency fluctuations. In order to make comparisons of speech with and without social-cognitive stress, measurements were collected while participants completed a speaking task before and during TSST-M conditions. Results AWS showed significantly higher levels of self-reported state and trait anxiety compared to ANS. Autonomic nervous system changes revealed similar skin conductance level and heart rate across pre-TSST-M and TSST-M conditions; however, RSA levels were significantly higher in AWS compared to ANS across conditions. There were no differences found between groups for speaking rate, fundamental frequency, and percentage of other disfluencies when speaking with or without social stress. However, acoustic analysis revealed higher levels of 2nd formant frequency fluctuations in the AWS compared to the controls under pre-TSST-M conditions, followed by a decline to a level that resembled controls when speaking under the TSST-M condition. Discussion Results suggest that AWS, compared to ANS, engage higher levels of parasympathetic control (i.e., RSA) during speaking, regardless of stress level. Higher levels of self-reported state and trait anxiety support this view point and suggest that anxiety may have an indirect role on articulatory variability in AWS.