Roza M. Vlasova, Abstract Co-Author: Nothing to Disclose

Ekaterina Pechenkova PhD, Abstract Co-Author: Nothing to Disclose

Valentin E. Sinitsyn MD, PhD, Presenter: Nothing to Disclose

Elena Mershina, Abstract Co-Author: Nothing to Disclose

Tatiana V. Akhutina DSc, Abstract Co-Author: Nothing to Disclose

In intraoperative brain mapping the action naming task is shown to be more promising for localization of Broca’s area than the object naming task (Rofes, 2012). The present study compares effectiveness of the object naming and picture verb generation task for localization of Broca’s area in fMRI.

18 healthy volunteers (age 20-50, 10 women) and 8 patients with a space-occupying lesion in the left frontal lobe (age 17-40, 5 women) took part in the study. All participants were right-handed and native speakers of Russian. During the experimental blocks participants viewed pictures of objects and were asked to either silently name them (object naming) or to silently name actions that could be performed with these objects (picture verb generation task). Patients performed only the second task. In the control blocks participants passively viewed pictures of distorted objects. Patients performed only the second task. Functional MR images were acquired using EPI sequence on Siemens Avanto 1.5T scanner (whole brain imaging, TR 2.52 sec., voxel size 3.6x3.6x3.8mm). Data were analyzed with SPM8 software. Lateralization index (LI) was calculated for the inferior frontal gyrus voxels only.

In healthy participants brain activation in experimental vs. control condition was found in triangular and/or opercular part of the inferior frontal gyrus (Broca’s area) in 72,2% of participants for the object naming task and in 95% for the picture verb generation task (p<0.001, exact Fisher’s test). Mean LI was 0.55 (SD=0.4) for the object naming task and 0.86 (SD=0.26) for the picture verb generation task (Mann-Whitney U= 91.5; р=0,024). The patient group has shown no significant difference from the controls in either LI (U=47; p=0.18) or presence of activation (p>0.05).

Picture verb generation task results in more frequent localization and greater lateralization of Broca’s area than object naming task in healthy native speakers of Russian. Parameters of activation evoked by verb generation in patients with space-occupying lesions do not differ from those in healthy controls, so this task is recommended for pre-neurosurgical brain mapping.

The present study suggests that the picture verb generation task rather than object naming task should be used in pre-neurosurgical fMRI mapping of language processing.

Vlasova, R, Pechenkova, E, Sinitsyn, V, Mershina, E, Akhutina, T, Localization of Broca’s Area is more Effective with Picture Verb Generation than Object Naming Task in fMRI.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14017426.html