Background Distinct experimental studies have been conducted in persons with chronic pain in order to explore possible attentional bias towards pain related stimuli. One of the most applied experimental paradigms, in this context, is the emotional stroop task in which words with different emotional content are presented to the subjects (Andersson & Haldrup, 2003). This task appears as a relevant tool to investigate the role of emotional mechanisms in the modulation of attentional resources in chronic pain conditions (Asmundson, Wright & Hadjistavropoulos, 2005).
Objectives Explore the possible modulation of attentional resources and executive control processes by pain related stimuli in people with Fibromyalgia (FM).
Methods An emotional stroop paradigm was presented to 22 women diagnosed with Fibromyalgia (FM; M =53.64 years, SD =8.92) and 21 controls (M =46.95 years, SD =9.74). Participants were asked to point out the color of different words that were distributed in alternate blocks of pain related words or neutral words. Pain related stimuli were extracted from the McGill Pain Questionnaire. Neutral words were selected from a dictionary taking “Diccionario de frecuencias de las unidades linguísticas del Castellano” (Alameda & Cuetos, 1995) into consideration psycholinguist similarities with the pain selected words. These stimuli were then tested and validated in another group of participants with FM.
Results From the mixed design ANOVA applied the results showed significant differences in the group (F[1,41]=4.482, p=0.040). The posthoc analysis yielded significant differences between groups (p<0.05). When compared to controls, participants with FM revealed a higher rate of errors in the color identification of the words, regardless of the emotional content.
Conclusions Overall, the results support the hypothesis that people with FM may have more difficulties in the inhibition and executive control of an automatic response (reading) and, in this context, the emotional content of the word does not have a specific impact in the measured behavioral outcomes (no differences according to the word emotional valence). Even so and to explore further the question of attentional bias towards pain related information in FM, it is crucial to collect and conjugate other type of indicators, such as electrophysiological activity (event-related potentials) and self-report measures.
Alameda, J. R., & Cuetos, F. (1995). Diccionario de frecuencias de las unidades linguísticas del Castellano. Oviedo: Servicio de publicaciones de la Universidad de Oviedo.
Andersson, G., & Haldrup, D. (2003). Personalized pain words and Stroop interference in chronic pain patients. European Journal of Pain, 7, 431–438. doi:10.1016/S1090-3801(03)00002-8
Asmundson, G., Wright, K & Hadjistavropoulos, H. (2005). Hypervigilance and attentional fixedness in chronic musculoskeletal pain: Consistency of findings across modified stroop and dot-probe tasks. The Journal of Pain, 6 (8), 497–506.
Acknowledgements Supported by the grant from Fundação para a Ciência e Tecnologia SFRH/BD/80389/2011 and supported by grant PI13/01759 from the Ministry of Economy and Competitiveness: Institute of Health Carlos III (ISCIII) of Spain.
Disclosure of Interest None declared