Study On The Control Of Rapid Saccade In The Frontal And Parietal Lobe Based On TMS Technology

Human can dynamically adjust their behavior to adapt to the environment in accordance with changes in the environment.In the course of behavior adjustment,the participation of cognitive control is needed to complete the suppression of the prepared behavior and the encoding of the new appropriate behavior.Studies have found that many factors influence behavioral adjustments,and emotions also influence behavioral adjustments.The inferior frontal gyrus(IFG)and intraparietal suleus(IPS)in the Frontal and Parietal lobes may be involved in response adjustment and response monitoring as important brain regions of the inhibition network and attention network,while the specific neural mechanism is not yet clear.Eye movement is widely used in cognitive research as a type of behavioral output.In order to explore the relationship between emotions and cognitive control and the role of the IFG and top IPS in behavioral adjustment,we adopted a double-step eye-saccade experimental paradigm.In this experimental paradigm,when the stimulus target appears in the no-step trial type,the subject needs to make a rapid saccade as soon as possible.In the step trial type,the target position changes,and the subject needs to suppress the initial saccade and redirect to the new one.So this paradigm contains the suppression,update and response monitoring.The first experiment was to investigate the interference of task-independent emotions on response monitoring.We explored the relationship between taskindependent emotions and cognitive control by adding four emotional faces(positive,neutral,fear,sad)before the stimulus.The experimental results showed that 1)when with positive emotion faces,the difference of the no-step saccadic reaction time under two conditions(following step vs following no-step)disappears;2)the higher the emotional pleasure of the face is,the smaller the difference of the no-step saccadic reaction time under two conditions is.The results showed that positive emotions affect the response monitoring function in cognitive control and interfere with the ability of human response monitoring and their own responses adjusting;the higher the degree of pleasure is,the more obvious the interference to cognitive control is;the task-independent emotions does not affect response suppression due to the weakness of interference.The second experiment is based on the TMS technology to study the modulation of the right IFG in the rapid saccade.Using the offline cTBS mode stimulation,TMS stimulation was performed on the right IFG and primary motor cortex(control point),and eye movement data was collected and analyzed to explore the neural mechanism ofthis brain region in rapid eye movement response inhibition,response updating,and response monitoring The experimental results showed that 1)TMS stimulated the right IFG,compared with the stimulation control point,the inhibition of the left visual field was significantly improved,while the inhibition rate of the right visual field did not change significantly,and all the saccades facing the left visual field The response time did not change;2)When TMS stimulated the right IFG,the difference of the no-step saccade response time under both conditions(following step vs following no-step)became greater.The results showed that the right IFG was involved in the inhibition of saccades;the right IFG was not involved in saccade suppression indirectly by not controlling the start-up time,and it was more likely that it was directly involved in the inhibition of the source of inhibitory signals in network RIN to suppress eye movements,the right IFG did not participate in the restart of the new response after inhibition for response monitoring,TMS stimulation of the right IFG enhances response monitoring.The third experiment is based on the TMS technology to study the modulation effect of the right IPS in the rapid eye saccade.Using the same design as in the second experiment,TMS stimulation was performed on the right IPS and the primary motor cortex(control point),eye movement data was collected and analyzed to explore the neural mechanism of the saccade initiation and saccadic response the rapid double-step saccade.The neural mechanism in the saccadic response adjustment.The results showed that 1)When the right IPS was stimulated in the no-step,the accuracy of the loci of the saccade of the eye toward the contralateral field of vision became better,and there was no difference in reaction time;2)When the right IPS was stimulated,and facing the opposite visual field,the new target appears in the opposite direction compared to the same visual field,and the reaction time of correcting the saccade becomes slower.The results showed that the modulation of IPS on the start of saccades is mainly reflected in the transformation of the spatial coordinate position.No direct connection was found in this experiment during the time course,when facing the opposite visual field and the new target appeared in the opposite direction.The correction saccade has a pronounced loss of space-position renewal.This loss was only reflected in the time course and did not interfere with the accuracy itself.In conclusion,task-independent emotional response monitoring has a disturbing effect,and the higher the degree of pleasure is,the more obvious the interference is.The right IFG may play a role in inhibiting the source,directly affecting the response inhibiting,and modulating the response time of response monitoring.The right IPS participates in the spatial position transition of the saccade,which is mainly responsible for the modulation of the loci of the saccade.The virtual lesion in the IPS will produce a loss of saccade response time in a specific direction.