The role of left occipitotemporal cortex in reading: reconciling stimulus, task, and lexicality effects

Cereb Cortex. 2013 Apr;23(4):988-1001. doi: 10.1093/cercor/bhs093. Epub 2012 Apr 13.


Although the left posterior occipitotemporal sulcus (pOTS) has been called a visual word form area, debate persists over the selectivity of this region for reading relative to general nonorthographic visual object processing. We used high-resolution functional magnetic resonance imaging to study left pOTS responses to combinatorial orthographic and object shape information. Participants performed naming and visual discrimination tasks designed to encourage or suppress phonological encoding. During the naming task, all participants showed subregions within left pOTS that were more sensitive to combinatorial orthographic information than to object information. This difference disappeared, however, when phonological processing demands were removed. Responses were stronger to pseudowords than to words, but this effect also disappeared when phonological processing demands were removed. Subregions within the left pOTS are preferentially activated when visual input must be mapped to a phonological representation (i.e., a name) and particularly when component parts of the visual input must be mapped to corresponding phonological elements (consonant or vowel phonemes). Results indicate a specialized role for subregions within the left pOTS in the isomorphic mapping of familiar combinatorial visual patterns to phonological forms. This process distinguishes reading from picture naming and accounts for a wide range of previously reported stimulus and task effects in left pOTS.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Analysis of Variance
  • Brain Mapping*
  • Female
  • Functional Laterality / physiology*
  • Humans
  • Imaging, Three-Dimensional
  • Magnetic Resonance Imaging
  • Male
  • Nerve Net / blood supply
  • Nerve Net / physiology
  • Occipital Lobe / blood supply
  • Occipital Lobe / physiology*
  • Oxygen / blood
  • Photic Stimulation
  • Reaction Time / physiology
  • Reading*
  • Temporal Lobe / blood supply
  • Temporal Lobe / physiology*
  • Vocabulary*
  • Young Adult


  • Oxygen