Unravelling neurotransmitters impairment in primary progressive aphasias

Hum Brain Mapp. 2023 Apr 15;44(6):2245-2253. doi: 10.1002/hbm.26206. Epub 2023 Jan 17.


Primary progressive aphasias (PPAs) are a group of neurodegenerative diseases mainly characterized by language impairment, and with variably presence of dysexecutive syndrome, behavioural disturbances and parkinsonism. Detailed knowledge of neurotransmitters impairment and its association with clinical features hold the potential to develop new tailored therapeutic approaches. In the present study, we applied JuSpace toolbox, which allowed for cross-modal correlation of magnetic resonance imaging (MRI)-based measures with nuclear imaging derived estimates covering various neurotransmitter systems including dopaminergic, serotonergic, noradrenergic, GABAergic and glutamatergic neurotransmission. We included 103 PPA patients and 80 age-matched healthy controls (HC). We tested if the spatial patterns of grey matter volume (GMV) alterations in PPA patients (relative to HC) are correlated with specific neurotransmitter systems. As compared to HC, voxel-based brain changes in PPA were significantly associated with spatial distribution of serotonin, dopamine, and glutamatergic pathways (p < .05, False Discovery Rate corrected-corrected). Disease severity was negatively correlated with the strength of GMV colocalization of D1 receptors (p = .035) and serotonin transporter (p = .020). Moreover, we observed a significant negative correlation between positive behavioural symptoms, as measured with Frontal Behavioural Inventory, and GMV colocalization of D1 receptors (p = .007) and serotonin transporter (p < .001). This pilot study suggests that JuSpace is a helpful tool to indirectly assess neurotransmitter deficits in neurodegenerative dementias and may provide novel insight into disease mechanisms and associated clinical features.

Keywords: behavioural disturbances; magnetic resonance imaging; neurotransmitters; positron emission tomography; primary progressive aphasia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aphasia, Primary Progressive* / diagnostic imaging
  • Aphasia, Primary Progressive* / metabolism
  • Brain / diagnostic imaging
  • Brain / metabolism
  • Brain / pathology
  • Humans
  • Magnetic Resonance Imaging
  • Pilot Projects
  • Receptors, Dopamine D1*
  • Serotonin Plasma Membrane Transport Proteins* / metabolism


  • Receptors, Dopamine D1
  • Serotonin Plasma Membrane Transport Proteins
  • SLC6A4 protein, human
  • DRD1 protein, human