Hemispheric lateralisation can be assessed with both functional magnetic resonance imaging (fMRI) and functional transcranial Doppler ultrasonography (fTCD). However, concordance between these techniques is imperfect. This discrepancy may be partially explained by differences in the fMRI and fTCD laboratory environments: while fMRI occurs in a noisy, confined space while subjects lie supine, fTCD typically occurs in a quiet, unconfined space while subjects sit upright. This study investigated the influence of the fMRI and fTCD laboratory environments on the measurement of language lateralisation. FTCD was used to measure of language lateralisation while participants performed a word generation task either twice in an fTCD environment (control group), or once in an fTCD environment and then in a simulated fMRI environment (experimental group). A Bayesian analysis revealed evidence of no effect of the laboratory environment on absolute lateralisation change scores. However, relative to the control group, test-retest reliability of lateralisation indices was considerably lower in the experimental group. This may have been driven by several individuals, whose lateralisation indices switched from positive to negative between the two assessments. Consistent with this, several participants in the experimental group switched lateralisation categories between the two testing session. These findings suggest that the laboratory environment may partially account for the discordance between fMRI and fTCD lateralisation estimates. Future research should embrace protocols that aim to reduce the interference of the laboratory environment, such as noise-cancelling headphones and open, multi-postural fMRI, to further our understanding of hemispheric lateralisation.
|Title of host publication||7th Australasian Cognitive Neuroscience Society Conference|
|Subtitle of host publication||Conference Proceedings|
|Place of Publication||Newcastle, NSW|
|Publisher||Australasian Cognitive Neuroscience Society|
|Number of pages||1|
|Publication status||Published - 2017|
|Event||Australasian Cognitive Neuroscience Society Conference (7th : 2017) - UniSA, University of Adelaide, and Flinders University, Adelaide, Australia|
Duration: 23 Nov 2017 → 26 Nov 2017
|Conference||Australasian Cognitive Neuroscience Society Conference (7th : 2017)|
|Abbreviated title||ACNS Conference|
|Period||23/11/17 → 26/11/17|
Rapaport, H., Buchholz, J., Filardi, N., & Badcock, N. A. (2017). The influence of the laboratory environment on the measurement of language lateralisation. In 7th Australasian Cognitive Neuroscience Society Conference: Conference Proceedings (pp. 63). Newcastle, NSW: Australasian Cognitive Neuroscience Society.