Recognition of Emotional Facial Expressions and Alexithymia in Patients with Chronic Facial Pain

Objectives: Alexithymia, conceived as difficulties to identify emotions, is said to be related with several pain syndromes. This study examined the recognition of facially expressed emotions and its relation to alexithymia in subjects with chronic facial pain. Methods: A total of 62 subjects were recruited, with n=20 patients with chronic facial pain and n=42 healthy controls. All subjects were tested for the recognition of facially expressed emotions (Facially Expressed Emotion Labelling Test (FEEL test). The Toronto Alexithymia Scale (TAS-26) was used for the diagnosis of alexithymia. Results: Patients with chronic facial pain performed worse than controls at the FEEL task (p<.001) and showed higher total TAS scores (p<.001). This indicates the presence of alexithymia and facial emotion recognition deficits in the facial pain group. Discussion: It was concluded from the results that both the recognition of facially expressed emotions, and the ability to identify and describe one’s own feelings (TAS), are restricted in chronic orofacial pain patients. This relationship is particularly important in the treatment of chronic facial pain, indicating that it should become part of the treatment in addition to the therapeutic key issues, to influence the quality of life of the affected patients positively. INTRODUCTION Alexithymia is characterised by a lack of emotional consciousness and is often stated in connection with chronic pain syndromes and therefore, it seems to be an important factor in the development of a chronic facial pain syndrome [1-4]. It has been reported that alexithymia is associated with poor recognition of others’s facial expressions [5-7]. Causes of alexithymia are unknown. Presumptions go towards neurobiological causes such an interruption of the connection between the limbic system and parts of the thalamus [8]. Patients who are affected by chronic facial pain present a special challenge for all medical disciplines in pain community [1,9,10]. Compared to other chronic pain disorders, a high psychological and symbolic significance is assigned to the facial region as pain localization. Self-confidence and interpersonal relations can be influenced by chronic pain [11]. Viewing facial expressions of pain can activate cortical areas which are responsible for the direct experience of pain [12]. Emotion-generating regions of the brain are mutually connected among themselves, as well as with neuro modulatory systems and with other brain regions which are involved in sensory, motor and cognitive functions [13]. Interestingly, Neal et al. [14] found that patients with facial Botox treatments could not properly assess the facial expressions of other persons due to their own reduced muscular contractions. The inability to express feelings with mimics also disturbs the awareness of one’s own emotions [14,15]. How much this disorder in recognition of emotional expressions influences life and thinking of the affected persons is still unexplored. Human beings need a facial motor system which is correctly innervated afferently and efferently [11,16]. During a long term peripheral (facial) nociception like odontalgia, post-face traumas ,painful TMD’s, this may change brainstem and cerebral neural circuits which may lead to (facial)motor activity changes [17]. These changes are not only seen in the head-face.but also in Central Von Piekartz et al. (2018) Email: H.von-Piekartz@hs-osnabrueck.de Ann Psychiatry Ment Health 6(3): 1134 (2018) 2/7 pain-inhibiting pain-inhibiting posture and persistent pain in other body parts are not uncommon [1,16]. Chronic pain sufferers are often shown pain-related posture for fear of pain provocation. According to Neal et al. [14], a person recognizes the mimicry of another person only if he deciphers the perceived stimulus by the activation of his or her own muscles of the face. It is difficult to implement and recognize the mimicry of strangers due to the missing expression of one’s own emotional state. So it is quite sensible to think that people with chronic facial pain avoid showing emotions and make fewer facial expressions than people without pain. Testing facial emotion recognition (FER) may be a reliable way to research emotional processing in patients with facial pain. Current research in the field of somatoform disorders shows that a reduction of negative emotions after states of high arousal can predict a reduction of pain [18]. Additionally, skills in the field of emotion regulation can predict aspects of handling with chronic pain [19]. The correlation between negative affect or even depressive disorders and somatoform disorders lead to the idea, that emotion regulation plays a crucial role in chronic pain [20,21]. Other clues can be derived from research in the field from tension headache. Patients with tension headache underrate negative emotions and the degree of stress. Traue and colleagues discuss that negative reinforcement plays a key role in the process. The suppression of expressivity helps to avoid negative consequences – instead patients get tension headache [22]. This inefficient strategy to tackle social stress may be transferable to patients with chronic facial pain. In light of these facts, alexithymia could not only be a contributing factor but also an independent precursor in the development of chronic facial pain. Our hypothesis is that people with chronic facial pain would perform worse than controls in identifying facially expressed emotions (FEEL-Test) and that this deficit would not only be explained by the presence of alexithymia. MATERIALS AND METHODS The participants A total of 21 participants with chronic facial pain were recruited from our rehabilitation clinics in Germany. They needed to be aged between 18 and 65 years, have facial pain for a minimum of 12 months, and has to fit the Diagnostic Criteria for Temporomandibular Disorder (DV-TMD). Participants were required to report a score larger as 50 mm on the Coloured Analogue Scale (CAS)Participants were excluded if they had a change of permanent medications during the past six weeks as well as additional neurological histories or psychosomatic illness. One patient was excluded from participation based on psychosomatic conspicuousness. Controls (n=42) were age and gender matched and there were no outliers Data collection procedure The study participants were invited to the recruiting clinic. Prior to signing the informed consent, the subjects were informed about the study content and the study procedure. Any questions posed, were clarified. Subsequently, the diagnostic questionnaire and the Toronto Alexithymia Scale (TAS) were completed in a quiet, well lit room. Each participant was instructed to make themselves comfortable sitting in front of the laptop. It took a total of 30 minutes per subject, to collect the data.