Phonological and semantic processing during comprehension in Wernicke’s aphasia: a N400 and Phonological Mapping Negativity study

Robson, H., Pilkington, E., Evans, L., DeLuca, V. and Keidel, J. (2017) Phonological and semantic processing during comprehension in Wernicke’s aphasia: a N400 and Phonological Mapping Negativity study. Neuropsychologia, 100. pp. 144-154. ISSN 0028-3932 doi: 10.1016/j.neuropsychologia.2017.04.012

Abstract/Summary

Comprehension impairments in Wernicke’s aphasia are thought to result from a combination of impaired phonological and semantic processes. However, the relationship between these cognitive processes and language comprehension has only been inferred through offline neuropsychological tasks. This study used ERPs to investigate phonological and semantic processing during online single word comprehension. EEG was recorded in a group of Wernicke’s aphasia n=8 and control participants n=10 while performing a word-picture verification task. The N400 and Phonological Mapping Negativity/ Phonological Mismatch Negativity (PMN) event-related potential components were investigated as an index of semantic and phonological processing, respectively. Individuals with Wernicke’s aphasia displayed reduced and inconsistent N400 and PMN effects in comparison to control participants. Reduced N400 effects in the WA group were simulated in the control group by artificially degrading speech perception. Correlation analyses in the Wernicke’s aphasia group found that PMN but not N400 amplitude was associated with behavioural word-picture verification performance. The results confirm impairments at both phonological and semantic stages of comprehension in Wernicke’s aphasia. However, reduced N400 responses in Wernicke’s aphasia are at least partially attributable to earlier phonological processing impairments. The results provide further support for the traditional model of Wernicke’s aphasia which claims a causative link between phonological processing and language comprehension impairments.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/70109
Item Type	Article
Refereed	Yes
Divisions	Interdisciplinary Research Centres (IDRCs) > Centre for Integrative Neuroscience and Neurodynamics (CINN) Life Sciences > School of Psychology and Clinical Language Sciences > Department of Clinical Language Sciences Life Sciences > School of Psychology and Clinical Language Sciences > Language and Cognition
Publisher	Elsevier
Download/View statistics	View download statistics for this item