Features Of Attention Network Impairment In Adults With Temporal Lobe Epilepsy:Based On The Evidence Of Eye-Tracking And Neuroelectrophysiology

Part 1 Study on the characteristics of attention network impairment in adults with temporal lobe epilepsy based on scale,ANT and eye-tracking technologyBackground: Attention is the basis of all advanced cognitive functions of the human brain.Patients with Temporal Lobe Epilepsy(TLE)often have attention dysfunction,but the damaging mechanisms are still unclear.Eye-tracking technology can not only capture visual information related to eye movements effectively,but also combine cognitive task states as an important method to study the severity of cognitive impairment and its underlying neuro-psychological mechanisms.However,there has been few studies on the application of eye tracking technology in the evaluation of attention function in TLE patients.Purpose: To explore the features of TLE patients with attention impairment in the aspects of scales,attention network test(ANT)and eye tracking indicators as well as analyzing the consistency of each indicator.Methods: A total of 93 patients diagnosed with TLE at Xiangya Hospital,Central South University during May 2022 and December 2022 and 85 healthy controls matched with demographic characteristics such as age and gender were included in this study.All participants were required to complete evaluating scales of attention and memory functions,and then finish the ANT and record and analyze the indicators of ANT(Mean reaction time),eye tracking(Mean first saccade time,MFST;Total saccadic amplitude,TSA;Average saccadic amplitude,ASA;and Total saccadic counts,TSC)by an automatic attention evaluation platform based on computers and SR Research Eyelink1000 plus desktop eye tracking system.Results:(1)Compared with healthy controls,the attention function of patients with TLE was damaged obviously,as well as its three subnetworks(alert network,orientation network and executive control network).(2)The results of ANT found that compared with healthy controls,the mean reaction time(MRT)in the patients with TLE was significantly increased,indicating the orientation network(p < 0.001)and executive control network(p = 0.041)of TLE patients were impaired.(3)The results of eye tracking were as follows: There were longer MFST,more TSC and larger TSA in patients with TLE.And the MFST reflected the impaired orientation network(p = 0.046),TSC reflected the impairment of alerting network(p = 0.035),and MRT-MFST reflected impairment of orientation network(p = 0.006)and executive control network(p = 0.036).(4)The multi-dimension detection methods have significant correlations with each other in the evaluation of the participants’ attention function and their sub-networks.(5)The impaired attention function in TLE patients,often accompanied by the impaired memory function,both of which seriously influence the TLE patients’ quality of life.Additionally,other factors related to the quality of life in patients with TLE were also found,including the education level,disease course,the average duration of seizures,the direction of seizures,the numbers of anti-seizures medications and whether have epileptic aura.Conclusion: This study confirmed that the attention function of TLE patients and its three self-networks were significantly impaired from multiple dimensions.We found that patients with TLE usually took longer to fixate on the target for the first time,and have more eye saccades and larger saccades,which might be features of the impaired attention network based on the eye tracking technology.Our findings are helpful for early identification of patients with TLE combined with attention impairment,which have strong clinical guiding significance for long-term monitoring and intervention.Part 2 Study on the features of attention network impairments in adults with temporal lobe epilepsy based on neuro-electrophysiologyBackground: Attention dysfunction is one of the common comorbidities in TLE patients.Scalp electroencephalography(EEG)is a non-invasive monitoring method that records brain activity with millisecond temporal resolution.Neuronal activity can be manifested in the changes of the characteristic parameters of the cerebral cortex EEG signal,which will help to deepen the understanding of the mechanism of the process of TLE patients with attention impairments.Purpose: To investigate the features of neuro-electrophysiology changes in TLE patients with attention impairments.Methods: A total of 92 patients diagnosed with TLE at Xiangya Hospital,Central South University during May 2022 and December 2022 and 85 healthy controls matched with demographic characteristics such as age and gender were included in this study.All subjects are required to complete the Attention Network Test and record and analyze the subjects’ execution ERP components(N1,CNV,N200,P300 amplitude and latency)and EEG rhythm(theta,alpha,beta)energy changes during the ANT task through the computer-based and Brain Amp MR EEG data acquisition system’s multi-modal automatic attention function evaluation platform.Results:(1)Compared with controls,lower amplitudes of cue-related N1 component(p ≤ 0.004),N200 component(p = 0.008),CNV-O component(p ≤ 0.013),CNV-E component(p = 0.014),and target-related N1 component(p ≤ 0.01)and P300 component(p < 0.001)were found in patients with TLE as well as longer latency of target-related N200(p < 0.05)and P300 components(p < 0.004).(2)The components of cue-related N1,CNV-E,N200 and targetrelated N1 suggested the alert networks in patients with TLE were damaged,due to the fact that alter effects were found in controls(p ≤ 0.01)but not in TLE group.The cue-related N200 component indicated impaired orienting networks in patients with TLE,because orienting effects were found in controls(p < 0.001)but not in patients with TLE.The components of target-related N200 and P300 found impaired executive control networks in patients with TLE.There were executive control effects in controls(p ≤ 0.045),but not in patients with TLE.(3)During the cue period,the average energies of theta,alpha,and beta frequency band in the whole brain electrodes in the TLE group were significantly lower than those in the healthy controls(p < 0.001).During the target period,those indicators in the TLE group were significantly higher than those in the control group(p < 0.001).(4)The energy of theta,alpha and beta were all sensitive to the changes of alert and executive control network with time.Only the energy of beta band was sensitive to the changes of orienting network with time.(5)In the cue period,the ratio of theta/beta(p = 0.028)and theta/alpha(p = 0.016)of the TLE group were significantly higher than controls,indicating the attention function of TLE patients was significantly impaired.Conclusion: This study confirmed that the attention function of TLE patients was significantly impaired.Different ERP components could evaluate the efficiencies of different sub-network of attention function in TLE patients.Different EEG rhythms during ANT tasks in TLE patients have special patterns of attention network.This study deepened our understanding of the brain functional network mechanism of epilepsy,and was helpful to explore the multi-dimensional clinical indicators for evaluating whether neurological diseases are combined with attention impairments.