Dysfunctional Limbic Circuitry Underlying Freezing of Gait in Parkinson's Disease.
Neuroscience
; 374: 119-132, 2018 03 15.
Article
em En
| MEDLINE
| ID: mdl-29408498
ABSTRACT
Freezing of gait (FOG) is a poorly understood symptom affecting many patients with Parkinson's disease (PD). Despite growing evidence of a behavioral link between anxiety, attention and FOG in PD, no research to date has investigated the neural mechanisms that might explain this relationship. The present study therefore examined resting-state MRI functional connectivity between the amygdala, striatum and frontoparietal attentional control network in PD patients with (freezers nâ¯=â¯19) and without FOG (non-freezers nâ¯=â¯21) in the dopaminergic 'off' state. Functional connectivity was subsequently correlated with an objective measure of FOG severity and a subjective scale of affective disorder within each group. Connectivity between the right amygdala and right putamen was significantly increased in freezers compared to non-freezers (pâ¯<â¯0.01). Furthermore, freezers showed increased anti-coupling between the frontoparietal network and left amygdala (pâ¯=â¯0.011), but reduced anti-coupling between this network and the right putamen (pâ¯=â¯0.027) as compared to non-freezers. Key functional connections between the amygdala, putamen and frontoparietal network were significantly associated with FOG severity and a fear of falling. This study provides the first evidence that dysfunctional fronto-striato-limbic processes may underpin the link between anxiety and FOG in PD. It is proposed that freezers have heightened striato-limbic load and reduced top-down attentional control at rest, which when further challenged by the parallel processing demands of walking may precipitate FOG.
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Base de dados:
MEDLINE
Assunto principal:
Doença de Parkinson
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Transtornos Neurológicos da Marcha
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Sistema Límbico
Tipo de estudo:
Etiology_studies
Limite:
Aged
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Humans
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article