Research On Brain Activation And Functional Networks After Stroke Based On Functional Near-Infrared Spectroscopy In Different Motor Cognitive Tasks

ObjectiveRehabilitation of motor and cognitive dysfunction after stroke has always been the focus and difficulty of research.Previous studies have shown that while exercise training can improve motor function,it can also improve cognitive function.The two influence each other,but the neural network mechanism after stroke is still unclear.The purpose of this study is to use functional near-infrared spectroscopy(fNIRS)to explore and compare the specificity of brain activation and functional network connections between post-stroke patients and healthy people when performing different motor cognitive tasks.It is used to guide the formulation of clinical rehabilitation strategies and improve the research of related neuroregulatory mechanisms.MethodsThis study included 10 patients with left hemiplegia after stroke who met the inclusion criteria in the Department of Rehabilitation Medicine,The Fifth Affiliated Hospital of Guangzhou Medical University(September 2020 to December 2020)as the experimental group(Stroke group,Stroke group).At the same time,10age-matched healthy elderly were recruited as the healthy elderly control group(Healthy elder group,ELD group),and 10 healthy young people were recruited as the healthy young group control group(Healthy young group,YNG group).The subjects in the three groups received clinical function scale assessment and simultaneous fNIRS assessment under different sports cognitive paradigms.Among them,the clinical function scale assessment includes the mini-mental state examination(MMSE)to assess overall cognitive function,and Brunnstrom(hand)staging to assess the level of hand function.Synchronous fNIRS motor cognition experimental paradigm includes(1)right-hand motor task(simple motor task),(2)Stroop paradigm task(simple cognitive task),and(3)hands alternate motor task(motor-cognitive task).The selected 4 regions of interest(ROIs)are: left prefrontal cortex(LPFC),right prefrontal cortex(RPFC),and left motor cortex(left motor cortex).cortex(LMC)and right motor cortex(RMC).By recording the concentration of oxy-hemoglobin(Hb O)under different task paradigms,and calculating the functional connectivity(FC)between ROIs,it is used to observe and compare different groups of people(comparison between groups)and different tasks(within groups).Compare)the differences in brain activation and brain function connections between.Results1.The basic information results show that there is no statistical difference in age between the Stroke group and the ELD group(Stroke group 60.30±10.89 years old;ELD group 56.20±6.76 years old).There was no statistical difference in gender ratio among the Stroke group,ELD group and YNG group.2.The results of the Stroop paradigm task(simple cognitive task)showed that:Compared with the ELD group,the YNG group had a significantly shorter average response time and a significant reduction in the average number of errors,while the Stroke group had a significantly longer average response time and a significant increase in the average number of errors.All were statistically significant(P<0.05).3.The comparison of brain activation levels showed that in the right-hand motor task(simple motor task),compared with the ELD group,the activation of RPFC in the Stroke group was significantly higher(P<0.05),and the activation of LMC was significantly reduced(P<0.05).In the Stroop paradigm task(simple cognitive task),compared with the ELD group,the activation levels of LPFC,RPFC,LMC,PFC+MC in the YNG group were significantly increased(P<0.05);while the activation level of RPFC in the Stroke group was significantly increased(P<0.05),the degree of LMC activation was significantly reduced(P<0.05).In the alternating hands motor task(motor-cognitive task),compared with the ELD group,the activation levels of PFC,LMC,and PFC+MC in the YNG group were significantly reduced(P<0.05),while the activation level of RPFC in the Stroke group was significantly increased(P<0.05),the degree of LMC activation was significantly reduced(P<0.05).4.The comparison of the characteristics of brain functional connection showed that:Compared with the ELD group,the YNG group had a significant increase in the functional connection strength between all ROIs in the four motor cognitive tasks,and the difference was statistically significant(P<0.05).In the Stroke group,except for LPFC-RPFC in the right-hand motor task(simple motor task),the functional connection strength between other ROIs was significantly reduced(P<0.05);in the Stroop paradigm task(simple cognitive task),except for LPFC-RPFC In addition,the functional connection strengths among other ROIs were significantly reduced(P<0.05);the functional connection strengths of LPFC-LMC,RPFC-RMC,and LMC-RMC were significantly increased in the bi-hands alternating motor task(motor-cognitive task)(P <0.05).ConclusionThe activation and functional connection patterns of brain regions in the stroke group and healthy people(healthy elderly and healthy young people)under different motor cognitive tasks are different:1.In the pure motor task(right-hand motor task),the functional connection strength between the brain PFC and MC of the healthy elderly group decreases,and there is a compensatory trend of co-activation by the contralateral PFC and the ipsilateral MC.The stroke group tends to compensate for insufficient MC activation by overactivation of PFC on the side of the lesion,and the compensation mechanism of brain functional connection may originate from both sides of the brain.2.In simple cognitive tasks(Stroop paradigm tasks),the reduction of cognitive information processing ability caused by aging may be related to the weakening of the activation degree and functional connection strength between PFC and MC.The weakening of cognitive information processing ability caused by stroke is mainly compensated by enhancing the functional connection between PFCs.3.In the motor-cognitive task(hands alternating motor task),the healthy elderly group has a compensatory tendency that is activated by the joint activation of PFC and MC on both sides of the brain.In the stroke group,the activation of PFC on the right side of the brain was the main factor,and the functional connectivity between PFC and MC on both sides of the brain was significantly enhanced,and compared with other tasks,it was closer to the level of healthy people.4.Compared with pure motor or cognitive tasks,stroke patients can more effectively strengthen the brain function network connection in the motor-cognitive brain area through motor-cognitive tasks,thereby promoting brain function network remodeling.In clinical rehabilitation work,the exercise-cognitive training model can be used to guide the selection of rehabilitation intervention programs for stroke patients,promote nerve remodeling,and improve patient dysfunction.