The Effects Of Cyclic Pain On The Empathy Of Women With Primary Dysmenorrhea

Pain empathy refers to the ability to understand and respond to pain in others through a combination of observation,memory,knowledge,and reasoning.Pain is a kind of complex subjective feeling and emotional experience which is ubiquitous in people’s daily life and is easily affected by psychological factors such as cognition and emotion.Neuroimaging studies have found that there is an overlap between the pain network activated by self-pain and the pain empathy network activated by perceiving pain in others,suggesting that pain empathy and self-pain may interact.Current research has shown that pain empathy can promote an individual’s perception of their own pain,but it is not clear how self-pain affects pain empathy.Primary dysmenorrhea(PDM),classified as a cyclic menstrual pain,is a very common gynecological disease without organic lesions of the female reproductive system.As a painful disease,primary dysmenorrhea provides an excellent opportunity to explore how our own experience of pain affects pain empathy.In addition,since primary dysmenorrhea is only associated with lower abdominal pain during menstrual phase,and there is no obvious pain sensation at other phases,we can further explore the influence of individual status on pain empathy.In recent years,the task-based functional magnetic resonance experimental paradigm has been widely used in the study of pain empathy,which provides convenience for exploring the neural mechanism behind pain empathy by analyzing the signals of brain activity when empathy is triggered.In this study,PDM women were selected as the research object.Based on task-based and resting state functional magnetic resonance imaging(fMRI)techniques,the differences of brain activity between PDM women and healthy control(HC)in perceiving pain in others were investigated.Based on the results of inter-group differences,we discuss the relationship between abnormal activation of brain regions and clinical data,and further analyze how individuals’ persistent self-pain affects their pain empathy characteristics.The main results are as follows:1.Task-based fMRI studies reveal the effects of chronic self-pain on pain empathy.The results showed that PDM women showed higher pain empathy than HC,and this abnormal pain empathy was closely related to activation of the anterior insula(AI)during menstrual and luteal phases.There was no significant difference in pain empathy and brain activation between the menstrual and luteal phases.In addition,through the analysis of psychophysiological interaction,it was found that the functional connections of the AI-precuneus and the AI-orbitofrontal cortex were abnormally changed when PDM women performed the empathic task.2.Based on resting state fMRI,the effects of persistent menstrual cramps on resting state brain function and the correlation between self-pain and pain empathy in women with dysmenorrhea were investigated.The result showed that the eigenvector centrality of the AI decreased significantly in PDM women compared to HC.Through the analysis of mediating effect,we found that the current pain symptoms caused the change of individuals’ pain empathy ability by induce the abnormal activation pattern of the anterior insula during the execution of the empathic task.Meanwhile,the effect of long-term pain accumulation on brain activity may also lead to abnormal the AI activity when individuals perceive others’ pain,which eventually leads to the changes of pain empathy.In summary,persistent self-pain in PDM women may lead to abnormal functional activities in the brain areas related to the pain network of the central nervous system,which further affects the individual’s perception of pain in others.Meanwhile,the AI activity may play a regulatory role in the relationship between self-pain and pain empathy,which to some extent provides the possibility for further understanding of the neural mechanism of pain empathy.