Further validation of the Emotional Controls (ECON) paradigm: what types of emotional picture contents best modulate pain and nociception?

Abstract

In previous studies, emotion generated by a picture-viewing protocol has been shown to reliably modulate pain and physiological nociceptive reactions. The present study used 7 picture contents (mutilation, attack, death/grieving, neutral, families, sports/adventure, erotica) that ranged in valence (unpleasant to pleasant), as well as in arousal (low to high), to determine how each emotional category regulates pain/nociception. Participants (N = 114) viewed a total of 108 pictures presented in pseudorandom order. During 1/3 of the pictures, noxious electrocutaneous stimuli were delivered to the sural nerve to elicit pain and nociceptive responding. Immediately following each picture, participants rated emotional reactions along the dimensions of emotional valence and arousal. After each noxious stimulus, participants rated their subjective pain sensation and physiological nociceptive reactions (nociceptive flexion reflex, heart rate acceleration, skin conductance response) were recorded. All procedures were IRB approved. As expected, relative to neutral pictures, unpleasant pictures led to greater displeasure and pleasant pictures lead to greater pleasure. Moreover, there was significant variability in reported arousal from unpleasant contents (mutilation >attack > death) and pleasant contents (erotica > adventure > families). The most reliable modulation of pain and nociceptive reactions occurred during the most emotionally intense pictures: greatest facilitation of pain and nociceptive reactions occurred during mutilation pictures and the greatest inhibition occurred during erotic pictures. These results support past research, suggesting that the ECON paradigm is a valid and reliable methodology for studying emotional modulation of pain and nociception. This study extends that work by demonstrating that mutilation and erotica are the categories that elicit the strongest emotional modulation. Implications for future research are discussed. (This research was funded by a health research grant from the Oklahoma Center for the Advancement of Science and Technology.) In previous studies, emotion generated by a picture-viewing protocol has been shown to reliably modulate pain and physiological nociceptive reactions. The present study used 7 picture contents (mutilation, attack, death/grieving, neutral, families, sports/adventure, erotica) that ranged in valence (unpleasant to pleasant), as well as in arousal (low to high), to determine how each emotional category regulates pain/nociception. Participants (N = 114) viewed a total of 108 pictures presented in pseudorandom order. During 1/3 of the pictures, noxious electrocutaneous stimuli were delivered to the sural nerve to elicit pain and nociceptive responding. Immediately following each picture, participants rated emotional reactions along the dimensions of emotional valence and arousal. After each noxious stimulus, participants rated their subjective pain sensation and physiological nociceptive reactions (nociceptive flexion reflex, heart rate acceleration, skin conductance response) were recorded. All procedures were IRB approved. As expected, relative to neutral pictures, unpleasant pictures led to greater displeasure and pleasant pictures lead to greater pleasure. Moreover, there was significant variability in reported arousal from unpleasant contents (mutilation >attack > death) and pleasant contents (erotica > adventure > families). The most reliable modulation of pain and nociceptive reactions occurred during the most emotionally intense pictures: greatest facilitation of pain and nociceptive reactions occurred during mutilation pictures and the greatest inhibition occurred during erotic pictures. These results support past research, suggesting that the ECON paradigm is a valid and reliable methodology for studying emotional modulation of pain and nociception. This study extends that work by demonstrating that mutilation and erotica are the categories that elicit the strongest emotional modulation. Implications for future research are discussed. (This research was funded by a health research grant from the Oklahoma Center for the Advancement of Science and Technology.)