Abstract

Progressive apraxia of speech (PAOS) is a neurodegenerative disorder characterized by the deterioration of speech motor planning and execution abilities. Recent advancements in neuroimaging, particularly magnetic resonance imaging (MRI), have provided insights into the structural and functional alterations associated with PAOS. Among these, spatial distributions of heightened magnetic susceptibility (SDHMS) have emerged as a promising avenue for understanding the neuroanatomical correlates of this disorder. This article explores the significance of SDHMS in PAOS, aiming to unravel the underlying neuropathological mechanisms. SDHMS patterns, visualized through susceptibility-weighted imaging (SWI) or quantitative susceptibility mapping (QSM), reveal alterations in brain tissue magnetic properties, reflecting changes in iron concentration, myelin content, and tissue microstructure. Neuroimaging studies have identified SDHMS patterns localized to brain regions implicated in speech motor control, including the supplementary motor area, precentral gyrus, insula, basal ganglia, and cerebellum. Understanding the spatial distributions of heightened magnetic susceptibility in PAOS offers insights into the selective neurodegeneration of speech motor networks, providing valuable information for clinical diagnosis and therapeutic intervention. Further research into the significance of SDHMS in PAOS may lead to improved diagnostic accuracy, prognostic markers, and targeted interventions for individuals affected by this disorder.