Atypical Local Interference Affects Global Processing in Children with Neurofibromatosis Type 1.

OBJECTIVES: To examine hierarchical visuospatial processing in children with neurofibromatosis type 1 (NF1), a single gene disorder associated with visuospatial impairments, attention deficits, and executive dysfunction.

METHODS: We used a modified Navon paradigm consisting of a large "global" shape composed of smaller "local" shapes that were either congruent (same) or incongruent (different) to the global shape. Participants were instructed to name either the global or local shape within a block. Reaction times, interference ratios, and error rates of children with NF1 (n=30) and typically developing controls (n=24) were compared.

RESULTS: Typically developing participants demonstrated the expected global processing bias evidenced by a vulnerability to global interference when naming local stimuli without a cost of congruence when naming global stimuli. NF1 participants, however, experienced significant interference from the unattended level when naming both local and global levels of the stimuli.

CONCLUSIONS: Findings suggest that children with NF1 do not demonstrate the typical human bias of processing visual information from a global perspective. (JINS, 2017, 23, 446-450).