Author/Authors :
Barekatain Majid نويسنده , Oghabian Mohammad Ali نويسنده Research Centre for Science and Technology in Medicine, Tehran University of Medical Sciences , Nilipour Reza نويسنده Department of Speech Therapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. Nilipour Reza , Khoshkhouy Delshad Haleh نويسنده Neuroimaging and Analysis Group, Research Center for
Molecular and Cellular Imaging, Tehran University of Medical
Sciences, Tehran, Iran
Abstract :
Background Neural correlates of visual confrontation naming (VCN)
have received considerable attention in previous literature. Recently,
there have been a few studies that have reported the activation of the
hippocampus during VCN tasks. Whether or not the hippocampus is directly
involved in picture naming has clinical importance for patients with
refractory mesial temporal lobe epilepsy (MTLE) who should undergo
anterior temporal lobe resection (ATLR). Objectives In this study, we
investigated the neural network of VCN and the role of the hippocampus
in Persian-speaking individuals by functional magnetic resonance imaging
(fMRI) VCN paradigm. Subjects and Methods Twenty right-handed, healthy,
Persian-speaking adults underwent fMRI while performing VCN task.
Pictures were selected from a Snodgrass and Vanderwart dataset that was
normed for Persian speakers. VCN performance was assessed and entered as
a covariate in whole-brain analysis. Region of interest (ROI)-based
analysis was also used to obtain more accurate results. Results
Activation in the left hippocampus was significantly correlated with VCN
performance. Participants with higher scores showed greater fMRI
activation in their left hippocampus. Activation in left
occipitotemporal regions, such as the left occipital fusiform gyrus,
left temporal occipital fusiform gyrus, left temporal pole, left middle
temporal gyrus, and left superior temporal gyrus also showed significant
correlation with VCN performance. The main effects of VCN were also
found in frontal and occipital regions, such as the left inferior
frontal gyrus, right inferior frontal gyrus, right orbital frontal
gyrus, right lateral occipital gyrus, right occipital fusiform gyrus,
and right occipital pole. Activation in the inferior frontal gyrus was
significantly left lateralized among all of the subjects. Conclusion
These findings suggest that good naming ability depends on fMRI
activation in the speech-dominant hippocampus. We also found that a
left-dominant network of occipitotemporal regions plays a dominant role
in VCN performance in healthy Persian-speaking individuals.
