Enhancing the Standardized Field Sobriety Test to detect cannabis impairment: An observational study.

OBJECTIVE: The purpose of this study was to explore various tests of impairment that could potentially be added to the Standardized Field Sobriety Test (SFST) to enhance its sensitivity to identify drivers whose abilities are adversely affected by cannabis. METHODS: An observational study was conducted in which participants were invited to use their own cannabis at the research facility. Once prior to cannabis use and at four times during the 150 min after cannabis use, participants performed the three tests of the Standardized Field Sobriety Test (SFST) (i.e., Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand) as well as the Modified Romberg Balance and Finger to Nose tests. In addition, assessments were made of physiological indicators (i.e., eyelid, leg and body tremors, rebound dilation, lack of convergence) and vital signs (pulse, blood pressure and body temperature). Participants also completed a digit-symbol substitution task at each testing interval. With the exception of vital signs and the digit symbol task, all tests and assessments were administered and scored by certified Drug Recognition Experts using the standard procedures of the Drug Evaluation and Classification Program. RESULTS: Twenty minutes after vaping cannabis (mean THC concentration = 6.34 ng/mL), participants displayed performance deficits on a variety of tasks; 67% met the criterion for suspected impairment on the SFST. Addition of the Finger-to-Nose (FTN) test along with observations of head movements and jerks (HMJ) increased the percentage of participants who met the criterion for suspected impairment by 33% and improved the sensitivity of the test from 0.67 to 0.88. CONCLUSIONS: The results of this study support supplementing the SFST with the Finger-to-Nose test and observations of HMJ to assist in the detection of drivers who are adversely affected by the use of cannabis. The observational study design and the use of assessors who were not blinded as to the use of cannabis by participants limits the strength of the evidence. Further research, including randomized trials and field studies of drivers, is required to confirm and validate this enhanced version of the SFST.

Reducing Vocal Fatigue While Preserving Realism During Video Game Voice-Overs Using the Vocal Combat Technique: A Randomized Controlled Trial.

OBJECTIVE: Vocal Combat Technique (VCT) teaches indirect and direct behavioral voice techniques to voice-over artists performing in violent video games. Although previous work on VCT has shown promise for mitigating dysphonia symptoms, a randomized clinical trial has yet to be undertaken. Therefore, we completed a randomized, controlled trial between a group of experienced video game voice-over actors receiving VCT and a control group comparison. METHODS: A total of 24 video game voice-over actors completed this study. Participants were randomly assigned to receive VCT or indirect vocal hygiene training prior to completing an intensive 1-hour video game voice recording session. The primary outcome was a change in Voice Handicap Index-10 (VHI-10) preperformance/postperformance. Secondary measures included a modified version of the Evaluation of the Ability to Sing Easily (m-EASE), the Vocal Tract Discomfort Scale (VTDS), and questions regarding return to work. Participants were also rated on the realism of their vocal performance by a blinded video game director. RESULTS: The VCT group showed a significantly smaller change in VHI-10 and m-EASE scores postperformance, and a higher increased likelihood to return to work compared to the control group. There were no group differences for VTDS or realism ratings. Four participants from the control group exhibited outlier behavior with more pronounced phonotraumatic symptoms following performance than all other participants. CONCLUSIONS: VCT shows evidence of mitigating symptoms of dysphonia while preserving the realism of the vocal performance. More work is needed to understand performers at risk for more severe vocal symptoms following extreme voice-over work, so as to target them for preventative techniques and voice preservation.

Mitigating Dysphonia, Pain, and Vocal Handicap after Violent Video Game Voice Overs: A Pilot Investigation into Vocal Combat Technique Training.

OBJECTIVE: to investigate how the Vocal Combat Technique (VCT) may mitigate vocal symptoms in voice over actors using vocal violence. METHODS: Five voice over actors (3 male, 2 females, Mean = 29.6 years) completed two study sessions of 45 minutes-to-1 hour of vocally violent voice over work held approximately 4 weeks apart. During session one, participants completed voice over work as they typically would, whereas they received 3-hours of VCT training to improve/assist in healthy vocal techniques prior to session two. Pre- and post-session measures for both sessions included self-perceptual ratings of vocal symptoms, auditory-perceptual evaluation, and traditional acoustic measures of frequency and perturbation. RESULTS: Participants showed substantial mitigating effects of VCT training on acoustic perturbation measures (jitter, shimmer, harmonics-to-noise ratio), and self-ratings of vocal symptoms (Vocal-Handicap Index-10, McGill Pain Scale for vocal discomfort, and Evaluation of the Ability to Sing Easily) with calculated medium to large effect sizes (d = 0.61-1.95). There were no changes in auditory perceptual ratings across sessions. CONCLUSION: Our pilot investigation yielded positive improvements in vocal symptomology in five voice over actors who were trained in VCT. Next steps should include a larger enrollment of voice actors to determine optimal preventative and recovery techniques.