Characteristics of facial expression recognition ability in patients with Lewy body disease

Facial muscle movements in patients with Parkinson's disease undergoing phonation tests

Purpose

Parkinson's disease (PD) is a serious neurodegenerative disease affecting the elderly. In general, the locomotion deficit, which seriously affects the daily life of patients with PD, usually occurs at a later stage. The mask face symptom meanwhile progressively worsens. However, facial muscle disorders and changes involved in the freezing mask are unclear.

Method

In this study, we recruited 35 patients with PD and 26 age- and sex-balanced controls to undergo phonation tests, while the built-in camera on the laptop recorded their facial expressions during the whole pronunciation process. Furthermore, FaceReader (version 7.0; Noldus Information Technology, Wageningen, Netherlands) was used to analyze changes in PD facial landmark movement and region movement.

Results

The two-tailed Student's t-test showed that the changes in facial landmark movement among 49 landmarks were significantly lower in patients with PD than in the control group (P < 0.05). The data on facial region movement revealed that the eyes and upper lip of patients with PD differed significantly from those in the control group.

Conclusion

Patients with PD had defects in facial landmark movement and regional movement when producing a single syllable, double syllable, and multiple syllables, which may be related to reduced facial expressions in patients with PD.

Normative data for Emotion Hexagon test and frequency of impairment in behavioral variant frontotemporal dementia, Alzheimer's disease and Huntington's disease

Social cognitive functions such as Theory of Mind, empathy and emotion recognition can be impaired in dementia spectrum disorders, especially in diseases with prominent frontal dysfunction. The Emotion Hexagon test (EHT) is a short test of basic emotion recognition. As with other social cognitive tests, normative data for this test is sparse. The aim of this study was to present regression-based normative data for the EHT. Further, we wished to investigate the frequency of impairment in patients with the behavioral variant of frontotemporal dementia (bvFTD, N = 11), Alzheimer's disease (AD, N = 44) and Huntington's disease (HD, N = 52) when using regression-based normative data. The results documented that age (but not gender or education) had a significant effect on EHT score. The effect of age had numerical impact on expected scores in persons older than 60 years. Normative data (including percentile estimates) are presented. The EHT is sensitive to impairment in both bvFTD and HD, where more than 80% of patients had lower scores than expected. In both groups, 54% of patients fell below the 5th percentile-estimate, and in HD 65% fell below the 10th percentile-estimate. In the AD group 25% fell below the 10th percentile-estimate, and 14% fell below the 5th percentile-estimate. In conclusion, very low scores are typically associated with HD and bvFTD, but very poor performances can also be found in other diseases such like AD. Hopefully, the normative data presented and the documentation of their validity in clinical practice is a useful tool for clinicians.