Abnormalities of language pathways in schizophrenia patients with and without a lifetime history of auditory verbal hallucinations: A DTI-based tractography study

Abstract

Objectives: Auditory verbal hallucinations (AVHs) are frequently observed in patients with schizophrenia (SZ) and could be the result of white matter (WM) fibre abnormalities involved in speech production/comprehension and perception. We evaluated WM integrity changes in SZ with (SZ+) and without (SZ–) lifetime AVHs compared to healthy controls (HCs), using diffusion tensor imaging-based tractography, with a novel focus on the structural connectivity within both intra- and interhemispheric fasciculi.

Methods: The study included 27 SZ+, 12 SZ– and 34 HCs. Fractional anisotropy (FA) and mean and radial diffusivities (MD and RD) were extracted in each participant in two left interhemispheric fasciculi and in the interhemispheric auditory pathway (IAP) to test integrity differences among groups.

Results: SZ– and SZ + compared to HCs presented increased diffusivities and/or decreased FA in the interhemispheric fasciculi. Decreased FA was significant only between SZ + and HCs for the IAP.

Conclusions: In this first comparison of integrity changes within both intra- and interhemispheric fasciculi, abnormalities in the intrahemispheric fasciculi were observed in both SZ– and SZ+, but an alteration in the IAP was seen only in SZ+. These results suggest that the IAP may be more involved in patients with AVHs-proneness.

Keywords:

• Schizophrenia
• auditory verbal hallucination
• language
• DTI
• tractography

Acknowledgements

We thank Annick Razafimandimby for technical assistance and Professors Perrine Brazo and Pascal Delamillieure for their clinical contribution. This work was supported by the French Health Ministry in a ‘Programme Hospitalier de Recherche Clinique (PHRC)’. This research can also be processed thanks to the Fondamental-Perceneige Price attributed to Sonia Dollfus for therapeutic innovation in mental diseases in 2014. We also thank San Francisco Edit for their contribution to language editing during preparation of the manuscript for publication. Funding sources were not involved in the study design, collection, analysis and interpretation of data, writing of the report, or the decision to submit the paper for publication.

Disclosure statement

None to declare.

Additional information

Funding

French Health Ministry in a ‘Programme Hospitalier de Recherche Clinique (PHRC)’. Fondamental-Perceneige Price award to Sonia Dollfus.