Allographic agraphia: a case study

Cortex. 2008 Jul-Aug;44(7):861-8. doi: 10.1016/j.cortex.2007.06.002. Epub 2007 Dec 23.

Abstract

We report the case of patient MN, diagnosed with frontotemporal dementia, who exhibited a severe impairment in writing letters and words in upper-case print in the face of accurate production of the same stimuli in lower-case cursive. In contrast to her written production difficulties, MN was unimpaired in recognizing visually presented letters and words in upper-case print. We find a modest benefit of visual form cueing in the written production of upper-case letters, despite an inability to describe or report visual features of letters in any case or font. This case increases our understanding of the allographic level of letter-shape representation in written language production. It provides strong support for previous reports indicating the neural independence of different types of case and font-specific letter-shape information; it provides evidence that letter-shape production does not require explicit access to information about the visual attributes of letter shapes and, finally, it reveals the possibility of interaction between processes involved in letter-shape production and perception.

Publication types

  • Case Reports
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged, 80 and over
  • Agraphia / complications*
  • Agraphia / diagnosis
  • Dementia / complications*
  • Dementia / diagnosis
  • Female
  • Handwriting*
  • Humans
  • Pattern Recognition, Visual*
  • Psychomotor Performance*
  • Reaction Time