Double dissociations of word and number processing in auditory and written modalities: A case study

Abstract

We report an individual with a massive left-hemisphere lesion, who showed reverse patterns of dissociations between word and number processing in two modalities (auditory comprehension and written production). His performance in auditory comprehension was perfect for words, but severely impaired for numbers. In written production, he performed significantly better at writing numbers (both Arabic numbers and word numbers) than writing words. His visual comprehension fell into normal range for words and numbers while his oral production was at floor for both. This case profile adds further evidence to the functional/neural segregation of word and number processing systems.

Keywords:

• Word processing
• Number processing
• Double dissociation
• Case study
• Chinese

Acknowledgments

This research was supported by the NSFC grants (30770715, 30700224). We are most grateful to ZY for his participation.

Notes

¹We specifically tested his short term memory spans for objects, words and digits in both auditory and visual modalities. He heard (for auditory) or saw (for visual) a series of object names, one-syllable words, or numbers, followed by a visual display of nine items (real objects, printed characters, or printed Arabic digits). He needed to point to the targets in the corresponding sequence (e.g., cup-scissors-watch for object sequence). His auditory short memory span and visual short memory span were equivalently impaired for the three stimuli types (ps > .05).