Using observational facial descriptors to infer pain in persons with and without dementia

Abstract Background For patients with advanced dementia, pain diagnosis and assessment requires observations of pain-indicative behavior by others. One type of behavior that has been shown to be a promising candidate is the facial response to pain. To further test how pain-indicative facial responses are, we investigated the predictive power of observational facial descriptors to (i) predict the self-report of pain and (ii) to differentiate between non-painful and painful conditions. In addition, the expertise of the observers (nurses vs. healthy controls) and the cognitive status of the observed (dementia vs. cognitively healthy) were considered. Methods Overall 62 participants (32 nurses and 30 control subjects) watched 40 video-clips, showing facial expressions of older individuals with and without dementia during non-painful and painful pressure stimulation. After each clip, participants were asked to rate the videos using commonly used facial descriptors of pain and also to provide global pain estimate ratings of how much pain the observed individual might have experienced. Results Out of the 12 facial descriptors used, only 7 were able to differentiate between non-painful and painful conditions. Moreover, participants were better in predicting the pain self-report of the observed individuals when using facial descriptors than when using global pain estimates. Especially, the anatomically-orienting descriptors (e.g. opened mouth, narrowing eyes) showed greatest predictive power. Results were not affected by pain-expertise of the observers (nurses vs. control subjects) or diagnostic status of the observed (patients with dementia vs. cognitively unimpaired subjects). Conclusions The fine-grained and specific observation of facial responses to acute pain appeared to provide valid indication of pain that is not compromised when patients with dementia are observed. The regular professional training does not put nurses at advantage to detect pain via facial responses

The impact of dementia on pain processing: subjective, facial, motor, and autonomic indicators

Aus klinischen Studien ist bekannt, dass Demenzpatienten weniger Schmerzmittel erhalten und weniger über Schmerzen berichten als kognitiv unbeeinträchtigte Personen gleichen Alters. Hieraus ergibt sich die Frage, inwieweit die Demenz Einfluss auf das Schmerzerleben und die Schmerzkommunikation nimmt. Dieser Frage nachzugehen, war das Ziel der vorliegenden Studie. 20 Demenzpatienten, 40 Personen mit einer Leichten Kognitiven Beeinträchtigung (LKBler) und 40 ältere Kontrollpersonen nahmen an der Studie teil. Es wurden die verbalen (Kategorialskala), mimischen (Facial Action Coding System), vegetativen (Herzratenreaktion) und reflektorischen Schmerzreaktionen (nozizeptiver RIII-Reflex) auf mechanische und elektrische Schmerzreize erfasst. Wir untersuchten ebenfalls 40 jüngere Kontrollprobanden, um den Einfluss des Alters auf die Schmerzverarbeitung mit demenzbedingten Veränderungen vergleichen zu können. Demenzbedingte Veränderungen: Es ergaben sich keine Gruppenunterschiede bezüglich der verbalen Schmerzbewertung der Reize, jedoch interferierte die Demenz deutlich mit der Fähigkeit zum verbalen Schmerzbericht (ein Großteil der Demenzpatienten hatte Schwierigkeiten die dargebotenen Reize zu bewerten). Die Analyse der Mimikreaktion ergab, dass Demenzpatienten bei vergleichbaren Reizstärken mimisch stärker reagierten. Interessanterweise war dieser Anstieg in den mimischen Schmerzreaktionen nicht auf einen unspezifischen Anstieg aller möglichen mimischen Akte zurückzuführen, sondern die mimische Schmerzreaktion der Demenzpatienten war genauso spezifisch wie die Mimikreaktion der älteren Kontrollprobanden. Die Schwelle des RIII Reflexes zeigte sich bei den Demenzpatienten signifikant vermindert. Bezüglich der Herzratenreaktion ergaben sich keine signifikanten Gruppenunterschiede. Die demenzbedingten Veränderungen ließen sich in abgeschwächter Form bereits bei den LKBlern nachweisen. Altersbedingte Veränderungen: Die altersbedingten Veränderungen in den Schmerzreaktionen unterschieden sich deutlich von den demenzbedingten Veränderungen. Folglich scheinen Alter und Demenz qualitativ unterschiedliche Einflüsse auf die Schmerzverarbeitung zu nehmen. Insgesamt weisen unsere Daten beunruhigenderweise in die Richtung, dass das Erleben von Schmerz im Verlauf der Demenz möglicherweise verstärkt wird. Klinisch betrachtet legen unsere Daten die Gefahr einer therapeutischen Unterversorgung von Demenzpatienten nahe, die ihre Ursache vermutlich in der eingeschränkten Fähigkeit zur Schmerzkommunikation hat.Clinical studies, suggesting a less frequent pain report and a reduce prescription of analgesic medication in patients with dementia, have raised the question whether pain perception changes across the course of dementia. The aim of the present study was to investigate the impact of dementia on pain perception and pain communication. 20 demented patients (with Alzheimer and vascular dementia), 40 patients with mild cognitive impairment and 40 cognitive unimpaired elderly controls were investigated for their subjective (category scale), facial (FACS), autonomic (heart rate) and motor (nociceptive flexion reflex) responses to mechanically and electrically induced pain. We also investigated 40 young subjects (20 - 40 years old) in order to compare age-related changes in pain responses to dementia-specific changes. Dementia-related changes: No group differences with regard to self-report ratings were found (though dementia interfered substantially with the subjects´ ability to provide self-report ratings of pain). In contrast, facial responses to pain were significantly increased in demented patients. Interestingly, this increase was not due to an unspecific enhancement of facial responses, since the facial expression of pain was as pain specific in demented patients as in healthy controls. We also found group differences regarding the nociceptive flexion reflex, with demented patients showing a significantly reduced reflex threshold. Heart rate responses did not differ between groups. These dementia-related changes were also seen (to a lesser extent) in the patients with mild cognitive impairment. Age-related changes: The age-related changes in pain responses differed considerably from the dementia-related changes, thus suggesting that age and dementia have qualitative different impacts on pain processing. The increased facial expression of pain as well as the decreased nociceptive flexion reflex threshold point to increased pain sensitivity in demented patients. Against the clinical background of a reduced prescription of pain medication in demented patients, our data suggest the danger of an undertreatment of pain in this patient group, probably due to the limited ability of demented patients to communicate pain

How to reduce mental health burden in health care workers during COVID-19? A scoping review of guideline recommendations

The COVID-19 pandemic has posed an unprecedented demand and a huge burden for healthcare workers (HCWs) worldwide, with alarming reports of heightened mental health problems. To counteract these mental health challenges, guidelines and recommendations for the support of HCWs during the COVID-19 pandemic have been published. With this scoping review and guideline evaluation, we aim to provide a critical overview of these guidelines and recommendations and to guide policy makers in establishing respective surveillance and care programs. In summary, 41 articles were included in this review which were published between April 2020 and May 2021. Across all articles, the guidelines and recommendations could be clustered into four main categories: “Social/structural support,” “Work environment,” “Communication/Information,” “Mental health support.” Although there was substantial agreement across articles about the recommendations given, empirical evidence on the effectiveness of these recommendations is still lacking. Moreover, most recommendations were developed without involving different members of the target group (HCWs) or other involved stakeholders. Strategies to detect potential barriers and to implement these guidelines in clinical practice are lacking

Attentional and emotional mechanisms of pain processing and their related factors: a structural equations approach

BACKGROUND/OBJECTIVE: It is known that maladaptive attentional and emotional mechanisms of pain processing – as indicated by constructs such as pain hypervigilance, pain-related anxiety and pain catastrophizing – play an important role in the development and maintenance of chronic pain conditions. However, little is known to date about the potential risk factors for these forms of maladaptive processing. The aim of the present study was to shed more light on this issue. A very comprehensive set of predictor variables was examined in healthy pain-free subjects

Mirroring Pain in the Brain: Emotional Expression versus Motor Imitation

Perception of pain in others via facial expressions has been shown to involve brain areas responsive to self-pain, biological motion, as well as both performed and observed motor actions. Here, we investigated the involvement of these different regions during emotional and motor mirroring of pain expressions using a two-task paradigm, and including both observation and execution of the expressions. BOLD responses were measured as subjects watched video clips showing different intensities of pain expression and, after a variable delay, either expressed the amount of pain they perceived in the clips (pain task), or imitated the facial movements (movement task). In the pain task condition, pain coding involved overlapping activation across observation and execution in the anterior cingulate cortex, supplementary motor area, inferior frontal gyrus/anterior insula, and the inferior parietal lobule, and a pain-related increase (pain vs. neutral) in the anterior cingulate cortex/supplementary motor area, the right inferior frontal gyrus, and the postcentral gyrus. The 'mirroring' response was stronger in the inferior frontal gyrus and middle temporal gyrus/superior temporal sulcus during the pain task, and stronger in the inferior parietal lobule in the movement task. These results strongly suggest that while motor mirroring may contribute to the perception of pain expressions in others, interpreting these expressions in terms of pain content draws more heavily on networks involved in the perception of affective meaning

Brain mechanisms associated with facial encoding of affective states

Affective states are typically accompanied by facial expressions, but these behavioral manifestations are highly variable. Even highly arousing and negative valent experiences, such as pain, show great instability in facial affect encoding. The present study investigated which neural mechanisms are associated with variations in facial affect encoding by focusing on facial encoding of sustained pain experiences. Facial expressions, pain ratings, and brain activity (BOLD-fMRI) during tonic heat pain were recorded in 27 healthy participants. We analyzed facial expressions by using the Facial Action Coding System (FACS) and examined brain activations during epochs of painful stimulation that were accompanied by facial expressions of pain. Epochs of facial expressions of pain were coupled with activity increase in motor areas (M1, premotor and SMA) as well as in areas involved in nociceptive processing, including primary and secondary somatosensory cortex, posterior and anterior insula, and the anterior part of the mid-cingulate cortex. In contrast, prefrontal structures (ventrolateral and medial prefrontal) were less activated during incidences of facial expressions, consistent with a role in down-regulating facial displays. These results indicate that incidences of facial encoding of pain reflect activity within nociceptive pathways interacting or possibly competing with prefrontal inhibitory systems that gate the level of expressiveness

Vicarious facilitation of facial responses to pain

Introduction: Observing facial expressions of pain has been shown to lead to increased subjective, neural and autonomic pain responses. Surprisingly, these vicarious facilitation effects on its corresponding response channel, namely facial responses to pain have mostly been neglected. We aim to examine whether the prior exposure to facial expressions of pain leads to a facilitation of facial responses to experimental pain; and whether this facilitation is linked to the valence (pain vs. neutral expression) or also linked to specific motor-features of the facial pain expressions (different facial muscle movements). Method: Subjective (intensity and unpleasantness ratings) and facial responses (Facial Action Coding System) of 64 participants (34 female) to painful and non-painful heat stimuli were assessed. Before each heat stimulus, video clips of computer-generated facial expressions (three different pain expressions and a neutral expression) were presented. Results: The prior exposure to facial expressions of pain led to increased subjective and facial responses to pain. Further, vicarious pain facilitation of facial responses was significantly correlated with facilitation of unpleasantness ratings. We also found evidence that this vicarious facilitation of facial responses was not only linked to the presentation of pain versus neutral expressions but also to specific motor-features of the pain cue (increase in congruent facial muscle movements). Discussion: Vicarious pain facilitation was found for subjective and facial responses to pain. The results are discussed with reference to the motivational priming hypothesis as well as with reference to motor priming. Significance: Our study uncovers evidence that facial pain responses are not only influenced by motivational priming (similar to other types of pain responses), but also by motor-priming. These findings shed light on the complexity -ranging from social, affective and motor mechanisms -underling vicarious facilitation of pain

Relationship between chronotype and pain threshold in a sample of young healthy adults

Introduction: Chronotype indicates the biological preference for timing of activity and sleep. Being a late chronotype (ie, having a tendency for late sleep times) is associated with several mental and physical health problems. Previous studies found that late chronotypes are also more susceptible to chronic pain, but the relationship between chronotype and pain sensitivity remains unclear. Objectives: The aim of this study was to investigate the relationship between chronotype and heat pain threshold (as an indicator of pain sensitivity) in a sample of young healthy adults. Methods: We analyzed data from 316 young healthy adults participating in 4 different studies run at the Medical Faculty of the University of Augsburg. In all studies, chronotype and other sleep variables (eg, sleep duration) were assessed using the micro Munich ChronoType Questionnaire. Heat pain threshold was assessed with the method of adjustment. Results: Chronotype was not significantly associated with the heat pain threshold. Entering the other sleep variables in separate regression models did also not significantly explain variance in heat pain threshold. Conclusion: Our null findings are in contrast with previous notions that late chronotypes might be more sensitive to pain and more susceptible to chronic pain. Given the scarcity of the literature on this topic, more studies are needed to clarify the relationship between chronotype and pain sensitivity in different age populations, while also considering distinct pain modalities or other types of pain tests