Research On Empathy Of Woman With Primary Dysmenorrhea Based On Multivariate Analysis

Primary dysmenorrhea(PDM),as characterized by painful menstrual cramps,is not only a painful experience but also affects psychological and affective states of women,such as empathy.Empathy including emotional and cognitive factors is the ability to share and understand the feeling of others,which could in turn affect perception of pain.Neuroimaging studies have revealed partially shared neural substrates for somatic and sympathetic pain in healthy subjects.However,few neuroimaging studies on PDM have focused on the effect of menstrual pain on empathy of woman with PDM.Therefore,this paper aimed to explore the influence of menstrual pain on the empathy of women with PDM so that to improve the quality of life for women with PDM.Firstly,this paper explored the influence of menstrual pain on the pain empathy of woman with PDM in menstruation phases.Here we take a multivariate partial least squares(PLS)correlation approach to establish the relationship between pain intensity,pain empathy score and gray matter volume based on the whole brain gray matter volume data of structural magnetic resonance imaging.In our results,we found a "share" brain structures network which associated with both pain and empathy in women with PDM,mainly included the anterior insula(AI),thalamus,posterior central gyrus and medial frontal gyrus.Subsequently,we found that the average gray matter volume of these brain regions mediates the influence of dysmenorrhea on pain empathy through mediation analysis.Finally,general linear model was used to analyze the effects of long-term pain experience,state pain,and the average gray matter volume on empathy for pain.Our study indicated that the brain structure was the key factor in empathy for pain,and the long-term pain experience was also an important factor to pain empathy,while the state pain during the menstrual period had little effect on empathy for pain.Secondly,we also investigated the effect of long-term pain experience on trait empathy of woman with PDM during periovulatory,luteal and menstruation phases.We used PLS correlation to ask for the relationship between the four sub-indexes of Interpersonal Reactivity Index and the resting brain activity data based on resting-state functional MRI.In our results,we obtained a neural network including the AI and other regions which have a similar regulation pattern between women with PDM and HC.Furthermore,a network which had opposite regulation to empathy in the PDM group as compared with HC was also found,mainly including the inferior frontal gyrus,left precuneus,middle and superior temporal gyri.The above findings were not changed in the three phases between HC and PDM groups.It suggested that women with long-term pain experience had abnormal function of brain network for empathy processing,which did not vary with the pain or pain-free state across the menstrual cycle.In summary,this paper used MRI technology and PLS correlation analysis to explore the influence of menstrual pain on the empathy of women with PDM.The results of two study works found that the AI,inferior frontal gyrus,anterior central gyrus and other brain regions were important to regulate the empathy of women with PDM,and played an intermediary role between pain and empathy.Furthermore,the regulation ways of these brain regions to empathy didn't change with the state of pain.The long-term pain experience was the main reason that affected the empathy of women with PDM.