A double-blind phase II randomized controlled trial of an online cognitive bias modification for interpretation program with and without psychoeducation for people with chronic pain.

ABSTRACT: Cognitive bias modification for interpretation (CBM-I) is an effective intervention for anxiety, but there is only a single trial in people with chronic pain. The aim of this randomized controlled trial was to test CBM-I with and without psychoeducation for people with chronic pain. We randomized 288 participants to 4 groups comprising treatment (CBM-I vs placebo) with or without psychoeducation. One hundred and eighty-three participants (64%) completed 4, 15-minute training sessions over 2 weeks. The coprimary outcomes were pain interference and pain intensity. We also measured interpretation bias, fear of movement, catastrophizing, depression, anxiety, and stress. Participants with more psychopathology at baseline were more likely to dropout, as were those allocated to psychoeducation. Intention-to-treat analyses using linear mixed models regression were conducted. Training effects of CBM-I were found on interpretation bias, but not a near-transfer task. Cognitive bias modification of interpretation improved both primary outcomes compared with placebo. For pain interference, there was also a main effect favoring psychoeducation. The CBM-I group improved significantly more than placebo for fear of movement, but not catastrophizing, depression, or anxiety. Cognitive bias modification of interpretation reduced stress but only for those who also received psychoeducation. This trial shows that CBM-I has promise in the management of pain, but there was limited evidence that psychoeducation improved the efficacy of CBM-I. Cognitive bias modification of interpretation was administered entirely remotely and is highly scalable, but future research should focus on paradigms that lead to better engagement of people with chronic pain with CBM-I.

The time course of attentional biases in pain: a meta-analysis of eye-tracking studies.

ABSTRACT: Previous meta-analyses investigating attentional biases towards pain have used reaction time measures. Eye-tracking methods have been adopted to more directly and reliably assess biases, but this literature has not been synthesized in relation to pain. This meta-analysis aimed to investigate the nature and time course of attentional biases to pain-related stimuli in participants of all ages with and without chronic pain using eye-tracking studies and determine the role of task parameters and theoretically relevant moderators. After screening, 24 studies were included with a total sample of 1425 participants. Between-group analyses revealed no significant overall group differences for people with and without chronic pain on biases to pain-related stimuli. Results indicated significant attentional biases towards pain-related words or pictures across both groups on probability of first fixation (k = 21, g = 0.43, 95% confidence interval [CI] 0.15-0.71, P = 0.002), how long participants looked at each picture in the first 500 ms (500-ms epoch dwell: k = 5, g = 0.69, 95% CI 0.034-1.35, P = 0.039), and how long participants looked at each picture overall (total dwell time: k = 25, g = 0.44, 95% CI 0.15-0.72, P = 0.003). Follow-up analyses revealed significant attentional biases on probability of first fixation, latency to first fixation and dwell time for facial stimuli, and number of fixations for sensory word stimuli. Moderator analyses revealed substantial influence of task parameters and some influence of threat status and study quality. Findings support biases in both vigilance and attentional maintenance for pain-related stimuli but suggest attentional biases towards pain are ubiquitous and not related to pain status.

The effect of cognitive bias modification for interpretation on avoidance of pain during an acute experimental pain task.

Research confirms that patients with chronic pain show a tendency to interpret ambiguous stimuli as pain related. However, whether modifying these interpretive pain biases impacts pain outcomes is unknown. This study aimed to demonstrate that interpretation biases towards pain can be modified, and that changing these biases influences pain outcomes in the cold pressor task. One hundred and six undergraduate students were randomly allocated to receive either threatening or reassuring information regarding the cold pressor. They also were randomly allocated to 1 of 2 conditions in the Ambiguous Scenarios Task, in which they were trained to have either a threatening interpretation of pain (pain bias condition) or a nonthreatening interpretation of pain (no pain bias condition). Therefore, the study had a 2 (threat/reassuring)×2 (pain bias/no pain bias) design. Analyses showed that a bias was induced contingent on condition, and that the threat manipulation was effective. Participants in the pain bias condition hesitated more before doing the cold pressor task than those in the no pain bias condition, as did those in the threat compared with the reassurance condition. The major finding was that interpretive bias mediated the relationship between bias condition and hesitance time, supporting the causal role of interpretive biases for avoidance behaviors in current chronic pain models. No differences were found on other pain outcomes regarding bias or threat, and the efficacy of the bias modification was not impacted by different levels of threat. These results suggest that cognitive bias modification should be further explored as a potential intervention in pain.