Performance on Paced Auditory Serial Addition Test and cerebral blood flow in multiple sclerosis

Acta Neurol Scand. 2013 Nov;128(5):e26-9. doi: 10.1111/ane.12129. Epub 2013 Apr 1.


Background: To assess the relationship between performance on the Paced Auditory Serial Addition Test (PASAT) and both cerebral blood flow (CBF) and axonal metabolic integrity in normal appearing white matter (NAWM) of the centrum semiovale in patients with multiple sclerosis (MS).

Methods: Normal appearing white matter of the centrum semiovale was investigated with magnetic resonance (MR) imaging in 28 non-depressed individuals (18 patients with MS and 10 healthy controls). CBF was assessed with pseudo-continuous arterial spin labeling. N-acetylacetate/creatine (NAA/Cr) ratios (a metabolic axonal marker) were measured using (1) H-MR spectroscopy. CBF was also measured in frontoparietal cortices and cerebellar hemispheres.

Results: In subjects with MS, we found a positive correlation between performance on the PASAT and CBF to the left centrum semiovale (P = 0.008), but not with the NAA/Cr ratio. There were no correlations between PASAT scores and CBF to the right centrum semiovale, frontoparietal cortices, and cerebellar hemispheres. There was no correlation between PASAT scores and NAA/Cr ratios.

Conclusions: Our preliminary results suggest that performance on the PASAT in subjects with MS correlates with CBF to the left centrum semiovale, which contains left frontoparietal white matter association tracts involved in information processing speed and working memory.

Keywords: Paced Auditory Serial Addition Test; cerebral blood flow; cognition; magnetic resonance spectroscopy; multiple sclerosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aspartic Acid / analogs & derivatives
  • Aspartic Acid / cerebrospinal fluid
  • Case-Control Studies
  • Cerebrovascular Circulation / physiology*
  • Creatine / cerebrospinal fluid
  • Disability Evaluation
  • Female
  • Humans
  • Linear Models
  • Magnetic Resonance Spectroscopy
  • Male
  • Middle Aged
  • Multiple Sclerosis / cerebrospinal fluid*
  • Multiple Sclerosis / physiopathology*
  • Statistics, Nonparametric
  • Tritium


  • Tritium
  • Aspartic Acid
  • N-acetylaspartate
  • Creatine