The Contribution Of The Left Precuneus To Emotional Memory In Migraine Without Aura

Background Migraine is one of the most common neurological diseases,affecting more than 1 billion people worldwide.Migraine without aura(MWo A)is the most common type.Emotional events are easier to be remembered than neutral events,which is called emotional enhancement of memory(EEM).At present,there are few studies on emotional memory in patients with MWo A,and the related neural mechanisms are not well understood.Objective To explore the difference of emotional memory mode between patients with MWo A and healthy controls(HC),and the correlation of the emotional memory performance with gray matter volume(GMV)and resting-state functional connectivity(rs-FC),and then to explore the possible neural mechanisms of emotional memory in patients with MWo A.Methods Twenty-seven MWo A patients(6 males,21 females,median age 31 years)and 25 healthy controls(10 males,15 females,median age 35 years)were included in this cross-section study.General demographic data of the two groups were collected,including gender,age,years of education.Mo CA(Montreal Cognitive Assessment)scores for cognition,and HAMA(Hamilton Anxiety Scale)and HAMD(Hamilton Depression Scale)scores for anxiety and depression were measured.Emotional memory behavior paradigm was performed.The emotional pictures stimulus were divided into 5 categories,negative picture with high arousal(NH)or with low arousal(NL),neutral picture(N)and positive picture with high arousal(PH)or with low arousal(PL),according to the arousal and valence.The incidental encoding,intentional encoding and "recognition-remember \ familiarity" extraction method was used.The precision of "recollection" was calculated as the Pr(Precision)index,and repeated measurement analysis of variance was performed,and the intrinsic emotional dimension of the picture stimulation,the valence(negative,neutral,and positive)× arousal(high arousal and low arousal)as intra-group factors,and groups(patient group and control group)as inter-group factors,Bonferroni corrected.Three-dimensional high-resolution T1 weighted structure images and resting state-functional MRI images were obtained.Voxel-based morphological measurements were used to assess the correlation between brain GMV and Pr in MWo A patients.Then the correlation between Pr and rs-FC of region of interest to whole brain was analyzed in the 2 groups.Results There was no statistical difference in gender distribution,education level,and age between MWo A patients and HCs.Patients' Mo CA scores were lower(p < 0.05),and HAMA and HAMD scores were higher(p < 0.05)than HCs,which mean lower cognitive function and more obvious anxiety and depression trend in MWo A.Under incidental encoding,the Pr of NH and negative stimuli were better than N,suggested that EEM(Pr emotional > Pr neutral,p < 0.05)was elicited in the patients with MWo A,as well as in HCs.But under intentional encoding,HCs no longer showed the effect,volunteers remembered neutral images as emotional ones.However,patients with MWo A continued showing worse recollection performance for the neutral images compared to NH and PH stimulus.The EEM(Pr emotional > Pr neutral,p < 0.05)was also elicited in the patients with MWo A under intentional encoding.Moreover,the Pr of PH under incidental encoding and Pr of PL under intentional encoding were negatively correlated with the GMV of the left precuneus(p < 0.05,FWE corrected).Taking the left precuneus in automatic anatomical labeling as the seed region,the precuneus-insula rs-FC was positively correlated to Pr of N under incidental encoding(p < 0.05,FWE corrected),and the precuneus-putamen rs-FC was positively correlated to Pr of PL under intentional encoding(p < 0.05,FWE corrected).No correlation was found between GMV of the left precuneus and recollection performance of emotional memory in HCs,and the related rs-FC of the left precuneus was also different from that in patients with MWo A.Conclusions Compared with healthy controls,who showed EEM effects only under incidental encoding,patients with MWo A showed EEM effects under incidental encoding and intentional encoding,indicating that there were differences in emotional memory patterns in MWo A patients.And the recognition performance of emotional memory was correlated to the gray matter volume and resting state-functional connectivity of the left precuneus in patients with MWo A,which was different from HCs.The left precuneus was involved in emotional memory in patients with MWo A.