Cognitive-behavioural models of chronic pain contend that appraisals of harm affect the individual's response to pain. It has been suggested that fear of pain and/or anxiety sensitivity predispose individuals to chronicity. According to this view, pain is maintained through hypervigilance towards painful sensations and subsequent avoidance. The present study investigates the nature of cognitive biases in chronic pain patients. A sample of 169 consecutive patients referred to a specialist pain management centre participated in the study. Questionnaires measuring different aspects of pain and a computerised version of the Dot-Probe Task were administered. Four types of words related to different dimensions of pain and matched, neutral words were used as stimuli. Reaction times in response to the stimuli were recorded. A factorial design 3 x 4 x 2 x 2 and ANOVAs were employed to analyse the data. Chronic pain patients showed a cognitive bias to sensory pain words relative to affective, disability, and threat-related words. However, contrary to expectations, those high in fear of pain responded more slowly to stimuli than those less fearful of pain. These results suggest that patients with chronic pain problems selectively attend to sensory aspects of pain. However, selective attention appears to depend upon the nature of pain stimuli. For those who are highly fearful of pain they may not only selectively attend to pain-related information but have difficulty disengaging from that stimuli. Theoretical and clinical implications of the data are discussed.

Evidence that patients with chronic pain selectively attend to pain-related stimuli presented in modified Stroop and dot-probe paradigms is mixed. The pain-related stimuli used in these studies have been primarily verbal in nature (i.e., words depicting themes of pain). The purpose of the present study was to determine whether patients with chronic pain, relative to healthy controls, show selective attention for pictures depicting painful faces. To do so, 170 patients with chronic pain and 40 age- and education-matched healthy control participants were tested using a dot-probe task in which painful, happy, and neutral facial expressions were presented. Selective attention was denoted using the mean reaction time and the bias index. Results indicated that, while both groups shifted attention away from happy faces (and towards neutral faces), only the control group shifted attention away from painful faces. Additional analyses were conducted on chronic pain participants after dividing them into groups on the basis of fear of pain/(re)injury. The results of these analyses revealed that while chronic pain patients with high and low levels of fear both shifted attention away from happy faces, those with low fear shifted attention away from painful faces, whereas those with high fear shifted attention towards painful faces. These results suggest that patients with chronic pain selectively attend to facial expressions of pain and, importantly, that the tendency to shift attention towards such stimuli is positively influenced by high fear of pain/(re)injury. Implications of the findings and future research directions are discussed.

This study examined the comparative efficacy of three interventions: a spouse-assisted coping skills training protocol for patients undergoing a multidisciplinary pain management programme (SA-MPMP), conventional patient-oriented multidisciplinary pain management programme (P-MPMP) and standard medical care (SMC). Thirty-six chronic low back pain (CLBP) patients and their spouses were randomly assigned to one of the three conditions. The SA-MPMP condition consisted of seven, weekly, 2-h, group sessions of training in dyadic pain coping and couple skills, delivered by a clinical psychologist with support of a multidisciplinary team of specialists, to patients together with their spouses. P-MPMP consisted of the SA-MPMP training delivered to the patient only (i.e., no spouse participation and assistance). The SMC condition entailed continuation of routine treatment, entailing medical care only. Data analysis revealed that, at the 12-month follow-up time point, patients receiving SA-MPMP had significant improvements in kinesiophobia and rumination about pain compared to those receiving P-MPMP and SMC. In patients suffering from CLBP, an intervention that combines spouse-assisted coping skills training with a multidisciplinary pain management programme can improve fear of movement and rumination about low back pain.

These results show clear evidence that chronic pain patients do demonstrate an interpretation bias towards painful faces and that this bias is greater for those who catastrophize more and have higher levels of fear of pain, but experienced less pain in the preceding week. Given the recent potential shown for interventions that modify cognitive biases, this paradigm would seem to be well suited to future efforts to modify interpretation biases in pain.

Research suggests that chronic pain patients demonstrate cognitive biases towards pain-related information and that such biases predict patient functioning. This study examined the degree to which a successful cognitive-behavioural program was able to reduce the observed attentional bias towards sensory pain words. Forty-two patients with chronic pain conditions for more than three months were recruited prior to commencing a cognitive-behavioural pain management program. Participants were assessed before the program, after the program and at one-month follow-up. Results confirmed that chronic pain patients exhibited biased attention towards sensory pain-related words at pre-treatment. These biases were still evident at post-treatment, but were no longer statistically significant at follow-up. Multiple regression analyses indicated that the changes in attentional bias towards sensory words between post-treatment and follow-up were predicted by pre- to post-treatment changes in fear of movement (Tampa Scale for Kinesiophobia) but not other relevant variables, such fear of pain or anxiety sensitivity. These results demonstrate that successful cognitive-behavioural treatments can reduce selective attention, thought to be indicative of hypervigilance towards pain. Moreover, these biases appear to be changed by reducing the fear associated with movement. Theoretically, these results provide support for the fear of (re)injury model of pain. Clinically, this study supports the contention that fear of (re)injury and movement is an appropriate target of pain management and that reducing these fears causes patients to attend less to pain-related stimuli.

Despite increasing interest in the attentional biases of pain patients towards pain-related stimuli, there have been no investigations of whether the main caregivers of chronic pain patients also selectively attend to pain-related information. We compared the attentional biases to painful or happy faces of 120 chronic pain patients, 118 caregivers, and 50 controls. Analyses found that both patients and caregivers demonstrated biases towards painful faces that were not observed in control participants or to happy faces. Those patients and caregivers who were high in fear of pain demonstrated greater biases than those low in fear of pain, and the biases of the high-in-fear-of-pain group differed significantly from zero. When sub-groups of caregivers were compared, it was found that biases towards painful faces were not observed for those caregivers who accurately identified the level of pain the patient currently reported. In contrast, those caregivers who overestimated or underestimated the patients' pain demonstrated biases that were significantly greater than zero. These results add to the growing weight of evidence suggesting that biases towards pain-related stimuli are observed in chronic pain patients, but that the nature of the stimuli is important. In addition, the results suggest that caregivers, particularly those who either under- or overestimate the level of pain that the patient reports, also demonstrate similar biases. Future research should investigate the links between caregivers' biases and the way in which caregivers respond to pain.

Introduction: This study investigated the time course of attention to pain and examined the moderating effect of attentional control in the relationship between pain catastrophizing and attentional bias in chronic pain patients. Methods: A total of 28 patients with chronic pain and 29 pain-free individuals observed pictures of pain, happy and neutral facial expressions while their gaze behaviour was recorded. Pain intensity and duration, anxiety, depression, stress, attentional control and pain catastrophizing were assessed by questionnaires. Results: In all subjects, the pattern of attention for pain faces was characterized by initial vigilance, followed by avoidance. No significant difference was found between the two groups in terms of orientation towards the stimuli, the duration of first fixation, the average duration of fixation or number of fixations on the pain stimuli. Attentional control moderated the relationship between catastrophizing and overall dwell time for happy faces in pain patients, indicating that those with high attentional control and high catastrophizing focused more on happy faces, whereas the reverse was true for those with low attentional control. Conclusion: This study supported the vigilance–avoidance pattern of attention to painful facial expressions and a moderation effect of attentional control in the association between pain catastrophizing and attentional bias to happy faces among pain patients.

Background: The refining process generates large volumes of wastewater containing a variety of chemical contaminants. The use of natural substitutes in treating wastewater which have fewer harmful effects is considered an effective step towards protecting the environment and sustaining the development of these industries. This study focused on the use of Moringa oleifera and alum at the Wastewater Unit at Bandar Abbas Refinery. Methods: This study was performed in 2014 in a laboratory using jar apparatus. These experiments were conducted in batch system and effective parameters including pH, coagulant dose and contact time were investigated on the wastewater obtained from Bandar Abbas Oil Refinery. Results: The jar test experiment showed that M. oleifera at 70 mg/L, optimum temperature, pH, and mixing speed could remove 38.60% of chemical oxygen demand (COD), 63.70% of turbidity, and 62.05% of total suspended solids (TSS). Also, alum at 40 mg/L removed COD, turbidity, and TSS by 51.72%, 92.16%, and 85.26% respectively from the refinery wastewater. Moreover, when M. oleifera and alum was used together with a 2:1 dosage ratio (alum at 80 mg/L and M. oleifera at 70 mg/L), they will remove COD, turbidity, and TSS by up to 50.41%, 86.14%, and 81.52% respectively. Conclusion: The use of M. oleifera as a natural coagulant is important in treating refinery wastewater not only from an environmental but also an economic point of view.