Pierre Philip* Could a Virtual Human Be Used to Universite´ de Bordeaux CNRS USR-3413 Explore Excessive Daytime Bordeaux, France Sleepiness in Patients? and Clinique du Sommeil, CHU Pellegrin Bordeaux, France Ste´ phanie Bioulac Universite´ de Bordeaux Abstract CNRS USR-3413 Bordeaux, France Excessive daytime somnolence (EDS) is defined as the inability to stay awake in daily and life activities. Several scales have been used to diagnose excessive daytime sleepiness, Poˆle de Pe´dopsychiatrie the most widely used being the Epworth Sleepiness Scale (ESS). Sleep disorders and Universitaire EDS are very common in the general population. It is therefore important to be able Hoˆpital Charles Perrens to screen patients for this symptom in order to obtain an accurate diagnosis of sleep France disorders. Embodied Conversational Agents (ECA) have been used in the field of affective computing and human interactions but up to now no software has been spe- Alain Sauteraud cifically designed to investigate sleep disorders. We created an ECA able to conduct Universite´ de Bordeaux an interview based on the ESS and compared it to an interview conducted by a sleep CNRS USR-3413 specialist. We recruited 32 consecutive patients and a group of 30 healthy volunteers Bordeaux, France free of any sleep complaints. The ESS is a self-administered questionnaire that asks the subject to rate (with a pen and paper paradigm) his or her probability of falling asleep. Cyril Chaufton For the purpose of our study, the ECA or real-doctor questionnaire was modified as Universite´ de Bordeaux follows: Instead of the ‘‘I’’ formulate, questions were asked as ‘‘Do you.’’ Our software CNRS USR-3413 is based on a common 3D game engine and several commercial software libraries. It Bordeaux, France can run on standard and affordable hardware products. The sensitivity and specificity and of the interview conducted by the ECA were measured. The best results (sensibility Clinique du Sommeil, CHU Pellegrin and specificity >98%) were obtained to discriminate the sleepiest patients (ESS 16) Bordeaux, France but very good scores (sensibility and specificity >80%) were also obtained for alert subjects (ESS<8). ESS scores obtained in the interview conducted by the physician Je´ roˆ me Olive were significantly correlated with ESS scores obtained in the interview the ECA con- Universite´ de Bordeaux ducted. Most of the subjects had a positive perception of the virtual physician and con- CNRS USR-3413 sidered the interview with the ECA as a good experience. Sixty-five percent of the Bordeaux, France participants felt that the virtual doctor could significantly help real physicians. Our results show that a virtual physician can conduct a very simple interview to evaluate EDS with very similar results to those obtained by a questionnaire administered by a real physician. The expected massive increase in sleep complaints in the near future likely means that more and more physicians will be looking for computerized systems to help them to diagnose their patients. 1 Introduction Excessive daytime sleepiness (EDS) is defined as sleepiness that occurs in a situation when an individual would usually be expected to be awake and alert (Littner et al., 2005). This very disabling symptom, which is responsible for Presence, Vol. 23, No. 4, Fall 2014, 369–376 doi:10.1162/PRES_a_00197 ª 2015 by the Massachusetts Institute of Technology *Correspondence to [email protected]. Philip et al. 369 Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/PRES_a_00197 by guest on 30 September 2021 370 PRESENCE: VOLUME 23, NUMBER 4 many traffic accidents (Philip, 2010), affects up to 19.5% bally and nonverbally. They can attract and maintain the of the general population in Western countries when attention of users in an interaction (Peters & Grandjean, subjective assessment is used (Ohayon, 2008, 2012). 2011), disambiguate written or spoken texts, and make This number is increasing owing to an increase in interactions more expressive and more socially adapted. chronic sleep deprivation in young people (Leger et al., ECAs can also control somewhat the communication of 2011) and an increase in obstructive sleep apnea in older their emotional states. They can display a large range of subjects (Norman & Loredo, 2008). Nevertheless, emotions (Arya, DiPaola, & Parush, 2009), such as dif- although EDS is becoming a real public health issue, ferent types of smiles (Ochs, Niewiadomski, Brunet, & very few physicians are trained to adequately differentiate Pelachaud, 2012). Emotions such as relief, embarrass- fatigue from EDS. Indeed fatigue, for which the treat- ment, anxiety, and regret can also be seen as sequences ment is rest, can be defined as a growing difficulty to per- of multimodal signals (Niewiadomski, Hyniewska, & form with a progressive decrease in performance. Sleepi- Pelachaud, 2011). In addition, several studies have ness, for which the treatment is sleep, is the difficulty in shown that when they use the vehicle of a humanoid remaining awake. face, human–machine interactions are perceived as being Both symptoms can alter performance but their causes similar to human–human interaction (Reeves & Nass, and treatments are radically different. This is a major 1996). The machine is perceived more as a socio-emo- issue because many patients suffering from sleep disor- tional actor than a tool (Reeves & Nass, 1996).This feel- ders are diagnosed as psychiatric patients (mood or anxi- ing is reinforced when the interface takes the form of an ety disorders) and therefore receive central nervous sys- ECA. tem drugs, which increase their level of sleepiness and ECAs have been used in a wide range of clinical appli- driving risk (Blazejewski, Girodet, Orriols, Capelli, & cations and they can act as therapists with whom human Moore, 2012; Orriols et al., 2011). patients can interact. The US Army has funded programs Several scales have been used to diagnose (Akerstedt to test the potential use of these software programs for & Gillberg, 1990; Hoddes, Zarcone, Smythe, Phillips, soldiers coming back from Iraq and suffering from post- & Dement, 1973) excessive or chronic daytime sleepi- traumatic stress disorder (PTSD) (Rizzo et al., 2009). ness, the most widely used being the Epworth Sleepiness They can also act as social companions to help teenagers Scale (ESS; Johns, 1991). This self-administered scale with substance abuse problems (Lisetti & Wagner, developed in the 1990s has been used in thousands of 2007). ECAs can also act as a patient seeking therapeutic studies and is the simplest way to self-evaluate EDS. assistance. Young practitioners interact with them to Sleep disorders are very common and EDS is a major learn how to interact with traumatic patients (Marsella, symptom associated with various sleep disorders such as Johnson, & LaBore, 2003). obstructive sleep apnea syndrome, restless legs syn- ECAs have been used in the field of affective comput- drome, and hypersomnias. It is therefore important to ing and human interactions (Garau, Slater, Pertaub, & be able to screen patients for this symptom in order to Razzaque, 2005) but up to now no software has been obtain an accurate diagnosis. specifically designed to investigate sleep disorders. Since Virtual reality has been used for clinical purposes for the ESS is the most widely validated scale to evaluate Ex- several years (Bioulac et al., 2012; Giroux et al., 2013) cessive Daytime Sleepiness (Johns, 2010), we hypothe- and there is a growing interest in Embodied Conversa- sized that although it was initially designed as a self- tional Agents (ECAs) to be used as a new type of administered questionnaire, it was a suitable model for human–machine interface (DeVault et al., 2013). ECAs assessing the ability of an ECA to investigate excessive aim to unite gesture, facial, and verbal expression to ena- daytime sleepiness. ble face-to-face communication with users, providing a We therefore created software (ECA) able to conduct strong means of human–system interaction. They are an interview based on the Epworth Sleepiness Scale autonomous entities that are able to communicate ver- (ESS) and compared it to an interview conducted by a Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/PRES_a_00197 by guest on 30 September 2021 Philip et al. 371 sleep specialist. Our main objective was to assess the sen- asleep. The ESS refers to driving, watching TV, talking sitivity and specificity of ESS scores collected by the to someone, or reading in common daily life situations ECA. where sleepiness is explored. The answers for the eight In order to minimize the self-perceived differences questions are added together to obtain a single score. A between the ECA and the real physician, subjects did score in the 0–8 range is considered to be normal while a not know whether the ECA was operated by a human score above 11 indicates moderate to severe sleepiness, (Wizard of Oz) or by artificial intelligence software. suggesting that expert medical advice should be sought. We have shown that high ESS scores (>15) correlate 2 Methods with the risk of traffic accidents (Philip, 2010), and sev- eral studies have shown that treatment affecting daytime 2.1 Population alertness significantly lowers ESS scores (Hardinge, Pit- We recruited 32 consecutive patients (18 men and son, & Stradling, 1995). 14 women, mean age: 46.7 6 12.8) attending the Bor- The ESS (Johns, 1991) was originally created with the deaux sleep clinic for a consultation and a group of 30 intention of preserving the exact wording of the ques- healthy volunteers (8 men and 22 women, mean age: tionnaire so as to provide a standardized test and pre- 37.3 6 11.0) free of any sleep complaints. Subjects were serve its validity. Its author recommends that the admin- informed that they would have an interview with a vir- istrator of the questionnaire not discuss the results of the tual physician operated by an ECA and then a similar ESS with the subject until it is completed, as this may interview with a real physician.