Isolated numerical skills in posterior cortical atrophy--an fMRI study

Neuropsychologia. 2006;44(10):1909-13. doi: 10.1016/j.neuropsychologia.2006.02.007. Epub 2006 Apr 4.

Abstract

Posterior cortical atrophy (PCA) is characterized by bilateral parieto-occipito-temporal atrophy and hypometabolism. Neuropsychological impairments include complex visual disturbances, alexia, agraphia, finger agnosia, right-left disorientation and dyscalculia. A recent case study reported severe numerical deficits with some selectively preserved numerical skills in a patient affected by PCA [Delazer, M., Karner, E., Zamarian, L., Donnemiller, E., & Benke, T. (2006). Number processing in posterior cortical atrophy--a neuropsycholgical case study. Neuropsychologia]. In a functional magnetic resonance imaging (fMRI) study brain activation patterns related to these selectively preserved numerical skills were analyzed. Recitation of multiplication tables and counting forward were contrasted to word recitation in a block design. Contrasts between experimental conditions and control condition yielded significant activation of inferior and medial temporal structures. Since numerical processing is generally associated with parietal activation, it was hypothesized that preserved brain structures would compensate for the functional deficits.

Publication types

  • Case Reports
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acoustic Stimulation / methods
  • Atrophy
  • Brain Mapping
  • Female
  • Functional Laterality / physiology
  • Humans
  • Magnetic Resonance Imaging*
  • Mathematics*
  • Middle Aged
  • Occipital Lobe* / blood supply
  • Occipital Lobe* / pathology
  • Occipital Lobe* / physiopathology
  • Oxygen / blood
  • Parietal Lobe* / blood supply
  • Parietal Lobe* / pathology
  • Parietal Lobe* / physiopathology

Substances

  • Oxygen