Evaluation of Subjective and Objective Levels of Drowsiness, it’s Rating and its Relation with Facial Dynamics

Abstract

Objective: To determine the subjective and observed levels of lethargy and changes in facial dynamics.
 Materials and Methods: This study was conducted at Department of community medicine, Services Institute of Medical Sciences Lahore for one-year duration from January 2017 to December 2018. The changes in facial dynamics, such as changes in eyes, lips and eyebrows, were tested in KKS (Karolinska Sleepiness Scale) in twenty-five drivers. And ORD (drowsiness observer rating). Repeated ANOVA measurements and repeated MANOVA measurements were used to analyze the data. In addition, a neural network and Viola-Jones were used to detect facial features. PERCLOS (percentage of eye closure), blink frequency and blink time were examined to see eye parameters. The size of the open mouth during sleep was examined for oral parameters. When examining the eyebrows, the number 50 indicates that the eyebrow is in the normal position. For eyebrows above the normal position, a range of 50 to 55 was specified; In addition, 45-50 was found to be a defined range for normal eyebrows.
 Results: Descriptive statistics of dynamic changes in the mouth and eyes showed increased drowsiness while driving, as well as changes in the eyes and mouth. However, statistical findings made while driving showed that dynamic eyebrow changes had a clear expression with a continuous trend. Similar studies on data obtained from CSR and ORD showed that both parameters increased at the same time and lethargy level. There was also a significant relationship between facial expressions and lethargy.
 Conclusion: This study will be an effective and efficient tool for alerting and detecting sleep in a timely and accurate manner.