Increased Effective Connectivity of the Left Parietal Lobe During Walking Tasks in Parkinson’s Disease

Abstract

Background: In Parkinson’s disease (PD), walking may depend on the activation of the cerebral cortex. Understanding the patterns of interaction between cortical regions during walking tasks is of great importance. Objective: This study investigated differences in the effective connectivity (EC) of the cerebral cortex during walking tasks in individuals with PD and healthy controls. Methods: We evaluated 30 individuals with PD (62.4±7.2 years) and 22 age-matched healthy controls (61.0±6.4 years). A mobile functional near-infrared spectroscopy (fNIRS) was used to record cerebral oxygenation signals in the left prefrontal cortex (LPFC), right prefrontal cortex (RPFC), left parietal lobe (LPL), and right parietal lobe (RPL) and analyze the EC of the cerebral cortex. A wireless movement monitor was used to measure the gait parameters. Results: Individuals with PD demonstrated a primary coupling direction from LPL to LPFC during walking tasks, whereas healthy controls did not demonstrate any main coupling direction. Compared with healthy controls, individuals with PD showed statistically significantly increased EC coupling strength from LPL to LPFC, from LPL to RPFC, and from LPL to RPL. Individuals with PD showed decreased gait speed and stride length and increased variability in speed and stride length. The EC coupling strength from LPL to RPFC negatively correlated with speed and positively correlated with speed variability in individuals with PD. Conclusion: In individuals with PD, the left prefrontal cortex may be regulated by the left parietal lobe during walking. This may be the result of functional compensation in the left parietal lobe.

Distinct serum GDNF coupling with brain structural and functional changes underlies cognitive status in Parkinson's disease

“…Critically, one study regarding attention deficits reported increased centrality of the PL in attention‐deficit/hyperactivity disorder patients 35 . In a PD patients walking research, it also showed that increased effective connectivity of the parietal lobe of PD patients played a compensatory role 36 . Yet, whether the IPL exists as an abnormal functional connection in PD‐low‐GDNF subjects remains unknown.…”

“… 35 In a PD patients walking research, it also showed that increased effective connectivity of the parietal lobe of PD patients played a compensatory role. 36 Yet, whether the IPL exists as an abnormal functional connection in PD‐low‐GDNF subjects remains unknown. One possibility is that an improperly connected IPL hub disrupts neural systems during task performance in real life, thereby causing impairments in executive functioning, including attention and working memory.…”

Role of exercise in modulating prefrontal cortical activation for improved gait and cognition in Parkinson’s disease patients

“…Furthermore, research focusing on cortical activation patterns in relation to gait adaptability, hemodynamic responses, and obstacle negotiation offers additional insights [ 24 - 26 ]. For instance, Pelicionie et al (2022) examined how patients with PD adjust their gait in response to varying walking conditions, such as changing speeds or avoiding obstacles, and found that these patients exhibit altered cortical activation, particularly in brain regions associated with motor planning and execution, during gait adaptability tasks.…”