Poster No:
2516
Submission Type:
Abstract Submission
Authors:
Hsin-Yun Tsai1, Ming-Tsung Tseng2
Institutions:
1Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Taiwan University, Taipei, Taiwan, 2Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine, Taipei, Taiwan
First Author:
Hsin-Yun Tsai
Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Taiwan University
Taipei, Taiwan
Co-Author:
Ming-Tsung Tseng
Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine
Taipei, Taiwan
Introduction:
Human pain perception arises from the integration of prior expectations with sensory evidence. Although recent work has demonstrated that treatment expectancy effects (e.g., placebo hypoalgesia) can be explained by an integration framework incorporating the precision level of expectations and sensory inputs, the key factor modulating this integration in stimulus expectancy-induced pain modulation remains unclear.
Methods:
In a stimulus expectancy paradigm combining emotion regulation in 31 healthy adults (both sexes), participants not only negatively or positively expected the upcoming electrocutaneous stimulus (i.e., expected an increased pain or a reduced pain, respectively) but were also instructed to attend to or downregulate their expectancy-associated emotions. By recording participants' skin conductance responses during the anticipation period, we confirmed the validity of emotion regulation on expectancy-induced emotions. Meanwhile, to investigate the underlying neural mechanisms, we collected participants' blood-oxygen-level-dependent (BOLD) signals by using the functional magnetic resonance imaging (fMRI) technology.
Results:
At the behavioral level, we found that participants' voluntary reduction in anticipatory anxiety and pleasantness monotonically reduced the magnitude of pain modulation by negative and positive expectations, respectively, indicating a role of emotion in stimulus expectancy effects of pain perception. For both types of expectations, Bayesian model comparisons confirmed that an integration model using the respective emotion of expectations and sensory inputs explained stimulus expectancy effects on pain better than using their respective precision. For negative expectations, the role of anxiety is further supported by our fMRI findings that (i) functional coupling within anxiety-processing brain regions (amygdala and anterior cingulate cortex) reflected the integration of expectations with sensory inputs, and (ii) anxiety appeared to impair the updating of expectations via suppressed prediction error signals in the anterior cingulate cortex, thus perpetuating negative expectancy effects. Regarding positive expectations, their integration with sensory inputs relied on the functional coupling within brain structures processing positive emotion and inhibiting threat responding (medial orbitofrontal cortex and hippocampus).
Conclusions:
In conclusion, the current study demonstrates that brain structures implicated in emotion processing integrate prior and novel pain experiences and may also influence the updating of pain predictions to underlie pain modulation by stimulus expectancy. Our findings add to the growing studies investigating the computational mechanisms behind expectancy modulation on pain.
Emotion, Motivation and Social Neuroscience:
Emotion and Motivation Other
Higher Cognitive Functions:
Higher Cognitive Functions Other
Modeling and Analysis Methods:
Activation (eg. BOLD task-fMRI) 2
Connectivity (eg. functional, effective, structural)
Perception, Attention and Motor Behavior:
Perception: Pain and Visceral 1
Keywords:
Emotions
Pain
Other - fMRI; expectation; pain modulation
1|2Indicates the priority used for review
Provide references using author date format
Grahl, A. (2018), 'The periaqueductal gray and Bayesian integration in placebo analgesia', eLife, vol. 7.
Shih, Y.-W. (2019), 'Effects of Positive and Negative Expectations on Human Pain Perception Engage Separate But Interrelated and Dependently Regulated Cerebral Mechanisms', Journal of Neuroscience, vol. 39, pp. 1261-1274.