Abstract
Background: Freezing of gait (FOG) in Parkinson's disease (PD) is a devastating clinical phenomenon that has a detrimental impact on patients. It tends to be triggered more often during turning (complex) than during forwarding straight (simple) walking. The neural mechanism underlying this phenomenon remains unclear and requires further elucidation.Objective: To investigate the differences in cerebral functional magnetic resonance imaging responses between PD patients with and without FOG during explicitly video-guided motor imagery (MI) of various complex (normal, freezing) and simple (normal, freezing) walking conditions.Methods: We recruited 34 PD patients, namely, 20 with FOG and 14 without FOG, and 15 normal controls. Participants underwent video-guided MI of turning and straight walking, with and without freezing, while their brain blood oxygen level-dependent (BOLD) activities were measured. Gait analysis was performed.Results: While comparing FOG turning with FOG straight walking, freezers showed higher activation of the superior occipital gyrus, left precentral gyrus, and right postcentral gyrus compared with non-freezers. Normal controls also manifest similar findings compared with non-freezers, except no difference was noted in occipital gyrus activity between the two groups. Freezers also displayed a higher effect size in the locomotor regions than non-freezers during imagery of normal turning.Conclusions: Our findings suggest that freezers require a higher drive of cortical and locomotion regions to overcome the overinhibition of the pathways in freezers than in non-freezers. Compared with simple walking, increased dorsal visual pathway and deep locomotion region activities might play pivotal roles in tackling FOG in freezers during complex walking.
Highlights
Freezing of gait (FOG) is manifested with “brief, episodic absence of, or marked reduction of forward progression of the feet despite the intention to walk” (Nutt et al, 2011)
There were no significant differences in age, gender, number of years of education, Vividness of Motor Imagery Questionnaire (VMIQ), and Mini-Mental State Examination (MMSE) among PDFOG, PDNOFOG, and normal controls
During the FOG gait, a significant activation occurred in the bilateral superior frontal, right middle frontal, right insula, and left superior temporal gyrus of PDFOG compared with PDNOFOG (Table 2 and Figure 3B)
Summary
Freezing of gait (FOG) is manifested with “brief, episodic absence of, or marked reduction of forward progression of the feet despite the intention to walk” (Nutt et al, 2011). Gait can be either simple (i.e., forward straight walking) or complex (i.e., turning), and FOG tended to be elicited more during complex walking situations (Rahman et al, 2008a; Spildooren et al, 2010; Shine et al, 2012; Smulders et al, 2016; Zhang et al, 2016). Turning, which requires more complex neural control than straight walking, is often more likely to cause freezing in PD patients with FOG (PDFOG). Freezing of gait (FOG) in Parkinson’s disease (PD) is a devastating clinical phenomenon that has a detrimental impact on patients. It tends to be triggered more often during turning (complex) than during forwarding straight (simple) walking. The neural mechanism underlying this phenomenon remains unclear and requires further elucidation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
