Articulatory network reorganization in Parkinson's disease as assessed by multimodal MRI and acoustic measures

• Published in: Parkinsonism & related disorders Vol. 84; pp. 122 - 128
• Main Authors: Klobusiakova, Patricia, Mekyska, Jiri, Brabenec, Lubos, Galaz, Zoltan, Zvoncak, Vojtech, Mucha, Jan, Rapcsak, Steven Z., Rektorova, Irena
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-03-2021
• Subjects: Acoustic analysis; Aged; Aged, 80 and over; Connectome; Dysarthria - diagnosis; Dysarthria - etiology; Dysarthria - pathology; Dysarthria - physiopathology; Female; fMRI; Gray Matter - diagnostic imaging; Gray Matter - pathology; Gray Matter - physiopathology; Humans; Hypokinetic dysarthria; Magnetic Resonance Imaging; Male; Multimodal Imaging; Nerve Net - diagnostic imaging; Nerve Net - pathology; Nerve Net - physiopathology; Parkinson Disease - complications; Parkinson Disease - diagnostic imaging; Parkinson Disease - pathology; Parkinson Disease - physiopathology; Parkinson's disease; Resting-state functional connectivity; Speech Acoustics; Temporal Lobe - diagnostic imaging; Temporal Lobe - pathology; Temporal Lobe - physiopathology; Voxel-based morphometry; fMRI; Resting-state functional connectivity; Parkinson's disease; Acoustic analysis; Hypokinetic dysarthria; Voxel-based morphometry
• ISSN: 1353-8020; 1873-5126
• DOI: 10.1016/j.parkreldis.2021.02.012

Hypokinetic dysarthria (HD) is common in Parkinson's disease (PD). Our objective was to evaluate articulatory networks and their reorganization due to PD pathology in individuals without overt speech impairment using a multimodal MRI protocol and acoustic analysis of speech.
A total of 34 PD patients with no subjective HD complaints and 25 age-matched healthy controls (HC) underwent speech task recordings, structural MRI, and reading task-induced and resting-state fMRI. Grey matter probability maps, task-induced activations, and resting-state functional connectivity within the regions engaged in speech production (ROIs) were assessed and compared between groups. Correlation with acoustic parameters was also performed.
PD patients as compared Tto HC displayed temporal decreases in speech loudness which were related to BOLD signal increases in the right-sided regions of the dorsal language pathway/articulatory network. Among those regions, activation of the right anterior cingulate was increased in PD as compared to HC. We also found bilateral posterior superior temporal gyrus (STG) GM loss in PD as compared to HC that was strongly associated with diadochokinetic (DDK) irregularity in the PD group. Task-induced activations of the left STG were increased in PD as compared to HC and were related to the DDK rate control.
The results provide insight into the neural correlates of speech production control and distinct articulatory network reorganization in PD apparent already in patients without subjective speech impairment.
•PD showed temporal decreases in speech loudness related to increased activation in the right-sided speech-related regions.•GMV loss in bilateral superior temporal gyri (STG) was associated with diadochokinetic irregularity in PD.•Increased activation of the STG might compensate for brain neurodegeneration leading to normal speech rhythmicity.•Our work provides new insight into the neural correlates of speech production control in PD.