Related Experiment Videos
Phonologically related lexical repetition disorder: a case study
1Department of Psychology, Washington University, and Cognitive Neurology Alzheimer's Research Center, Lawson Research Institute, St. Joseph's Health Care London, London Ontario, Canada. bgold@artsci.wustl.edu
Brain and Language
|April 13, 2001
Summary
Aphasia patients often substitute nonwords, but MMB showed many formal errors (real words sounding alike). Increased memory demands revealed semantic errors, supporting a continuum of language disorders.
Area of Science:
- Neuroscience
- Linguistics
- Psychology
Background:
- Aphasia, a language disorder post-brain damage, typically involves nonword substitutions in repetition tasks.
- Formal errors, or phonologically related lexical errors, involve real-word substitutions that sound similar to the target word.
Observation:
- This study details the case of patient MMB, who exhibited an exceptionally high frequency of formal paraphasias during repetition tasks.
- Six experiments investigated the underlying impairments and tested competing theories of formal error production.
Findings:
- MMB's formal errors were influenced by target word frequency but not length or imageability.
- Errors were often more frequent than targets, with maximal phonological overlap at the initial consonant.
- Increased auditory verbal short-term memory (AVSTM) demands induced semantic paraphasias, supporting a severity continuum model.
Implications:
- Findings partially support the Martin-Saffran interactive spreading activation model of formal errors.
- Results challenge Blanken's phonological interactive encoding account.
- The study suggests a continuum of lexical repetition disorders, from phonological to semantic errors, modulated by AVSTM capacity.