Asymmetric cortical activation in healthy and hemiplegic individuals during walking: A functional near-infrared spectroscopy neuroimaging study

Xiaokuo He; Lei Lei; Guo Yu; Xin Lin; Qianqian Sun; Shanjia Chen

doi:10.3389/fneur.2022.1044982

Asymmetric cortical activation in healthy and hemiplegic individuals during walking: A functional near-infrared spectroscopy neuroimaging study

Front Neurol. 2023 Jan 25:13:1044982. doi: 10.3389/fneur.2022.1044982. eCollection 2022.

Authors

Xiaokuo He¹, Lei Lei¹, Guo Yu¹, Xin Lin¹, Qianqian Sun², Shanjia Chen^{1

3}

Affiliations

¹ Department of Rehabilitative Medicine, Fifth Hospital of Xiamen, Xiamen, China.
² Department of Rehabilitative Medicine, Xiangyang Central Hospital, Xiangyang, Hubei, China.
³ Department of Rehabilitative Medicine, The First Affiliated Hospital of Xiamen University, Xiamen, China.

Abstract

Background: This study investigated the cortical activation mechanism underlying locomotor control during healthy and hemiplegic walking.

Methods: A total of eight healthy individuals with right leg dominance (male patients, 75%; mean age, 40.06 ± 4.53 years) and six post-stroke patients with right hemiplegia (male patients, 86%; mean age, 44.41 ± 7.23 years; disease course, 5.21 ± 2.63 months) completed a walking task at a treadmill speed of 2 km/h and a functional electrical stimulation (FES)-assisted walking task, respectively. Functional near-infrared spectroscopy (fNIRS) was used to detect hemodynamic changes in neuronal activity in the bilateral sensorimotor cortex (SMC), supplementary motor area (SMA), and premotor cortex (PMC).

Results: fNIRS cortical mapping showed more SMC-PMC-SMA locomotor network activation during hemiplegic walking than during healthy gait. Furthermore, more SMA and PMC activation in the affected hemisphere was observed during the FES-assisted hemiplegic walking task than during the non-FES-assisted task. The laterality index indicated asymmetric cortical activation during hemiplegic gait, with relatively greater activation in the unaffected (right) hemisphere during hemiplegic gait than during healthy walking. During hemiplegic walking, the SMC and SMA were predominantly activated in the unaffected hemisphere, whereas the PMC was predominantly activated in the affected hemisphere. No significant differences in the laterality index were noted between the other groups and regions (p > 0.05).

Conclusion: An important feature of asymmetric cortical activation was found in patients with post-stroke during the walking process, which was the recruitment of more SMC-SMA-PMC activation than in healthy individuals. Interestingly, there was no significant lateralized activation during hemiplegic walking with FES assistance, which would seem to indicate that FES may help hemiplegic walking recover the balance in cortical activation. These results, which are worth verifying through additional research, suggest that FES used as a potential therapeutic strategy may play an important role in motor recovery after stroke.

Keywords: functional electrical stimulation; gait; hemiplegia; stroke; treadmill walking.

Grants and funding

This research was funded by the Ministry of Science and Technology of Fujian (to XKH; Grant Nos.: 2020D025 and 2020CXB052), the Youth Innovation Project from the Ministry of Science and Technology of Fujian (Grant No.: 2022D010), the Medical and Health Guidance Project of Xiamen (to SJC; Grant No.: 3502Z20199100), and the Medical and Health Guidance Project of Xiamen (to LL; Grant No.: 3502Z20214ZD1).