EEG-based Emotional Cognition Study Of Premenstrual Syndrome In Women

Premenstrual syndrome(PMS)is the general term for the physical and psychological symptoms of fertile women that appear periodically during the luteal phase.These symptoms can disappear naturally with the onset of menstruation.PMS is one of the most frequent gynecological diseases among fertile women,and it has a serious negative impact on women's physical and mental health.In severe cases,there is usually a high suicide rate and a high risk of disease,which also causes a certain burden for social and economic development.Research had shown that PMS causes cognitive and emotional changes in women at different phases of the menstrual cycle.And the emotional clinical symptoms of PMS are similar to those of depression,characterized by an inability to suppress task-independent emotional stimuli.The pathogenesis of PMS is currently unclear.Most studies are based on hormone levels or magnetic resonance imaging(FMRI),trying to explain the pathological mechanism of PMS from physiological and brain functions,but they failed to detect the time-course characteristics of PMS patients in the process of affective cognition.And the current research on the neural mechanism of PMS Still relatively few.Electroencephalogram(EEG)is a signal from the central nervous system that gives a true snapshot of an individual's mental and emotional state during the cognitive process.Event-related potential(ERP)in EEG signals has the characteristics of high temporal resolution.We can speculate on the cognitive process of the brain by analyzing the difference in amplitude and latency of the waveform components of different events.Therefore,this paper used EEG to explore the characteristics of PMS patients in the process of emotional cognition.And event-related potential technique was used to analyze the differences of neural mechanisms in the management of emotional conflicts between PMS patients and healthy controls at different phases of the menstrual cycle.In this study,the word-face Stroop paradigm in was adopted,and emotional faces were used as experimental materials.PMS patients and healthy women were required to complete two tasks of emotional conflict and cognitive conflict in luteal phase and follicular phase respectively.EEG data were collected throughout the experiment,and the behavioral data and ERP data were analyzed.The conclusions are as follows:(1)This paper firstly analyzed the behavioral data of Stroop effect in conflict control of premenstrual syndrome.The results showed that the subjects in both tasks showed obvious Stroop effect,and the response time of the inconsistent condition was significantly longer than that of the consistent condition.In the emotional conflict task,the response time of PMS group to angry faces in luteal phase was significantly longer than that of happy faces,and the accuracy rate of luteal phase was significantly lower than that of follicular phase to the angry faces.The cognitive conflict task found that the response time of PMS patients was significantly longer than that of healthy women.The above results indicated that PMS women had significant differences in negative emotional face recognition at different phases of the menstrual cycle,and decreased conflict control ability in luteal phase compared with follicular phase.Due to the changes in premenstrual hormone levels,the ability of behavioral inhibition and antiintervention in luteal phase of PMS patients is less than that of the healthy control group,and the menstrual cycle has a greater impact on the control of emotional conflict in PMS patients.(2)In this paper,P200(positive wave with an lantency of 200ms),N250(nagetive wave with an lantency of 250ms),N450(nagetive wave with an lantency of 450ms)and SP(the late positive wave)components of PMS patients and healthy women were analyzed.P200 results showed that the brain of PMS patients in the early processing stage was slow to accept and process information related to tasks,and the processing of conflict stimuli was sensitive and affected by the menstrual cycle.The N250 results showed that the N250 amplitude of follicular phase in PMS group was significantly enhanced compared with that of luteal phase.It is suggested that PMS patients invest more attention resources on stimulation in follicular phase,which can well suppress the interference information.While PMS patients lack the inhibitory effect on emotional dispersion in luteal phase.Similar results were observed in terms of N450 components.The amplitude of N450 in luteal phase of PMS patients was significantly weaker than that in follicular phase,suggesting that PMS women were insensitive to stimulus information in luteal phase,and their conflict monitoring ability was reduced.In the later stages of brain processing,the enhanced SP amplitude may reflect that PMS patients have difficulty in separating attention from interfering stimuli during the luteal phase and are less able to resolve conflicts between faces and words.These results suggest that,compared with the healthy controls,PMS patients devote less resources to the task in the early stage of emotional conflict management and continue to the later cognitive stage.PMS patients pay relatively little internal attention to conflict stimuli in luteal phase and have cognitive deficits in conflict information.Impaired conflict control is one of the main characteristics of PMS patients,and the results of this study support the executive dysfunction shown in the PMS group during preconflict management.(3)In order to investigate whether EEG signals contain valuable features that can be used to identify PMS patients and healthy women,this paper used convolutional neural network(CNN)to extract the features of EEG signals autonomously to realize the classification of premenstrual syndrome.The classification results showed that the EEG signals of the subjects who completed the cognitive conflict task in luteal phase as the model input had the best recognition effect,and the recognition accuracy reached 77.37%.This study showed that the signal characteristics contained in EEG can be used to identify premenstrual syndrome and obtain a good classification effect.In this paper,we studied the affective cognitive process of women with premenstrual syndrome and healthy women based on EEG signals.The results of this paper improve our understanding of the neural mechanism in conflict management of PMS patients,and provide a certain theoretical basis and evidence-based basis for the auxiliary clinical diagnosis and treatment of PMS.