To robustly support hypotheses, my laboratory uses a converging methodology approach by leveraging results from behavior (e.g., language, memory, executive function) with multimodal neuroimaging techniques to assess the degree to which a behavior involves or requires brain regions and their anatomical and functional connections (neural network). In addition, we use task-related fMRI (activation, adaptation, functional connectivity; Schnur et al., 2009; Geng & Schnur, 2016; Wei & Schnur, 2019) methods to measure neurotypical speakers’ brain activations and connectivity during word production. For example, to determine whether the degree to which successful word selection relies on the connections between brain regions (e.g., the LIFG), we applied diffusion tensor imaging (DTI) and resting state (rs) fMRI to brain-behavior analyses (Harvey et al., 2013; Harvey & Schnur, 2015). This was the first demonstration of DTI deterministic tractography in stroke patients with aphasia (a region-of-interest approach to isolate white matter pathways which connect gray matter regions based on known anatomical terminations on a subject by subject basis) supported by converging functional connection evidence using rsfMRI. We demonstrated that the LIFG and white-matter tracts connecting it with the temporal lobe support a cognitive control mechanism which helps resolve interference from word competitors during word selection. My laboratory continues to apply multimodal neuroimaging techniques and statistical approaches to test hypotheses concerning the relationships between cognitive capacities, brain regions, and networks in both neurotypical speakers and persons with brain damage resulting from stroke.
Harvey, D.Y., Wei, T., Ellmore, T.M., Hamilton, A.C., & Schnur, T.T. (2013). Neuropsychological evidence for the functional role of the uncinate fasciculus in semantic control. Neuropsychologia, 51, 789-801. [Impact Factor 3.3] PubMed PMID: 23395830
Harvey, D., & Schnur, T.T. (2015). Distinct loci of lexical and semantic access deficits in aphasia: Evidence from voxel-based lesion-symptom mapping and diffusion tensor imaging. Cortex, 67, 37-58. [Impact Factor 4.9] PubMed PMID: 25880795
Geng, J., & Schnur, T.T. (2016). The role of features and categories in the organization of object knowledge: Evidence from adaptation fMRI. Cortex, 78, 174-194. [Impact Factor 4.9] PubMed PMID: 27085513
Wei, T., & Schnur, T.T. (2019). Neural and linguistic differences explain priming and interference during naming. BioRXiv 547745 [Preprint]. Available from: https://doi.org/10.1101/547745