Dichotic-listening performance after complete callosotomy: No relief from left-ear extinction by selective attention

Westerhausen, R.; Fabri, M.; Hausmann, M.

Abstract

The surgical section of the corpus callosum (callosotomy) has been frequently demonstrated to result in a left-ear extinction in dichotic listening. That is, callosotomy patients report the left-ear stimulus below chance level, resulting in substantially enhanced right-ear advantage (REA) compared with controls. A small number of previous studies also suggest that callosotomy patients can overcome left-ear extinction when the instruction encourages to attend selectively to the left-ear stimulus. In the present case study, we re-examine the role of selective attention in dichotic listening in two patients with complete callosotomy and 40 age- and sex-matched controls. We used the standardised Bergen dichotic-listening paradigm which uses stop-consonant-vowel syllables as stimulus material and includes both a free-report and selective-attention condition. As was predicted, both patients showed a clear left-ear extinction. However, contrasting the earlier reports, we did not find any evidence for a relief from this extinction by selectively attending to the left-ear stimulus. We conclude that previous demonstrations of an attention-improved left-ear recall in callosotomy patients may be attributed to the use of suboptimal dichotic paradigms or residual callosal connectivity, rather than representing a genuine effect of attention.

Citation

Westerhausen, R., Fabri, M., & Hausmann, M. (2023). Dichotic-listening performance after complete callosotomy: No relief from left-ear extinction by selective attention. Neuropsychologia, 188, Article 108627. https://doi.org/10.1016/j.neuropsychologia.2023.108627

• Journal Article Type: Article
• Acceptance Date: Jun 19, 2023
• Online Publication Date: Jun 20, 2023
• Publication Date: Sep 9, 2023
• Deposit Date: Jun 29, 2023
• Publicly Available Date: Jun 30, 2023
• Journal: Neuropsychologia
• Print ISSN: 0028-3932
• Electronic ISSN: 1873-3514
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 188
• Article Number: 108627
• DOI: https://doi.org/10.1016/j.neuropsychologia.2023.108627