Chronic Pain Patients’ Gaze Patterns toward Pain-Related Information: Comparison between Pictorial and Linguistic Stimuli

Abstract

Background and Objectives: The attentional bias and information processing model explained that individuals who interpret pain stimuli as threatening may increase their attention toward pain-related information. Previous eye tracking studies found pain attentional bias among individuals with chronic pain; however, those studies investigated this phenomenon by using only one stimulus modality. Therefore, the present study investigated attentional engagement to pain-related information and the role of pain catastrophizing on pain attentional engagement to pain-related stimuli among chronic pain patients by utilizing both linguistic and visual stimulus. Materials and Methods: Forty chronic pain patients were recruited from the rehabilitation center, the back pain clinic, and the rheumatology department of Chung-Ang University Hospital in Seoul, Korea. Patients observed pictures of faces and words displaying pain, presented simultaneously with neutral expressions, while their eye movements were measured using the eye tracking system. A t-test and ANOVA were conducted to compare stimulus pairs for the total gaze duration. Results: Results revealed that chronic pain patients demonstrated attentional preference toward pain words but not for pain faces. An ANOVA with bias scores was conducted to investigate the role of pain catastrophizing on attentional patterns. Results indicated that chronic pain patients with high pain catastrophizing scores gazed significantly longer at pain- and anger-related words than neutral words compared to those with low pain catastrophizing scores. The same patterns were not observed for the facial expression stimulus pairs. Conclusions: The results of the present study revealed attentional preference toward pain-related words and the significant role of pain catastrophizing on pain attentional engagement to pain-related words. However, different patterns were observed between linguistic and visual stimuli. Clinical implications related to use in pain treatment and future research suggestions are discussed.

Attentional Patterns Toward Pain-Related Information: Comparison Between Chronic Pain Patients and Non-pain Control Group

“…Moreover, attentional avoidance from pain-related information was also not observed for the high pain catastrophizing group during the later stage of attention. A previous study (Lee et al, 2019) that utilized similar research methods also found non-significant effects of pain catastrophizing on attentional bias to pain facial expressions. As discussed earlier, this result may be due to the fact that chronic pain patients' experience of outpatient hospital-based treatment alters their attentional patterns to pain facial expressions.…”

“…The result of the current study did not support the evidence for the attentional bias to pain facial expressions among chronic pain patient group. Previous research has found consistent evidence for the attentional bias to pain words but not for facial expression stimuli (Lee et al, 2019;Mazidi et al, 2019). It may be that facial expression stimuli are not as relevant to chronic pain patients' pain experiences as photos of affected areas or pain word stimuli.…”

“…Pain Intensity Questions ( Lee et al, 2018 , 2019 ) includes 3 items which assess (1) the degree of pain one currently feels, (2) the pain during the past week, and (3) the pain during the past 3 months. Participants rated on a 11-point scale, ranging from 0 to 10 Pain Facial Expression Scale.…”

“…Studies (Vervoort et al, 2013;Lee et al, 2018) that investigated adults with chronic pain in the community found that pain catastrophizing increases attentional bias to pain facial expressions. In contrast, another study (Lee et al, 2019) found no significant effect of pain catastrophizing on attentional bias to pain facial expressions; however, the authors argued that their study assessed a unique population of chronic pain patients who received hospital-based care for their chronic pain. They argued that experiencing a level of pain, and severity that required hospitalization, as well as exposure to intensive chronic pain treatment might have altered the participants' responses toward pain facial expressions.…”

“…A previous attentional bias meta-analysis (Gaffiero et al, 2019) found relatively consistent evidence for the attentional bias with word stimuli but inconsistent results for an attentional bias for facial expression stimuli. Some studies (Vervoort et al, 2013;Lee et al, 2018) found evidence for an attentional bias to pain facial expression stimuli among individuals with chronic pain whereas others (Lee et al, 2019;Mazidi et al, 2019) did not find significant results even though these studies mentioned above utilized the similar eye tracking methodology (i.e., utilizing facial expression photos sourced from the database such as Montreal database and KUFEC, and pairing pain facial expressions with neutral facial expressions while their eye movement were measured by an eye tracker).…”