Multi-modal Language Mapping

An illustrative example of cortical spatiotemporal propagation of high-gamma augmentation during visual naming (t=0 corresponds to image display)

(Left) Brain regions activated during a picture naming task. (Right) Cortical areas with significant high-gamma modulation observed during picture naming, based on averaged iEEG recordings across eight epilepsy patients. See (Arya, Babajani-Feremi, et a1., 2019) for more details.

Dr. Babajani-Feremi’s research comprehensively explores the neural mechanisms of language processing using an integrative approach that combines neuroimaging and electrophysiology. His studies leverage multi-modal methods—MEG, fMRI, and intracranial EEG (ECoG, sEEG)—to uncover spatial and temporal patterns in language function, including speech production and comprehension, and variations in cortical topography. This work has led to models of visual naming based on high-gamma activity, offering new insights into how brain regions and networks collaborate to facilitate language processing (Arya, Babajani-Feremi, et a1., 2019).

Comparison of language mapping techniques in a surgical epilepsy patient. Language mapping using electrical stimulation mapping (ESM) is compared with iEEG, MEG, fMRI, and TMS in a patient undergoing epilepsy surgery. The highlighted white areas represent the resected regions. Postoperative language deficits were observed in this patient, consistent with the resection of language areas identified by iEEG, fMRI, and MEG.

Dr. Babajani-Feremi’s studies have highlighted the predictive capabilities of pre-surgical mapping in determining language outcomes for patients undergoing neurosurgery (Babajani-Feremi et al., 2017). By integrating non-invasive (MEG and fMRI) and invasive (intracranial EEG) techniques, his research demonstrates how combining these methods can enhance the precision of language cortex localization, particularly in pediatric and clinical populations (Babajani-Feremi et el. 2019). These findings also explore the balance between invasive and non-invasive mapping approaches, emphasizing the benefits of tailored neuroimaging to improve diagnostic and therapeutic strategies for epilepsy and neurodegenerative conditions.

Successful localization of expressive language cortex in a 2-year-old patient using high-gamma modulation in iEEG recordings. (Top-Left) Pre- and post-surgery MRI scans showing the locations of two cortical tubers and the resected areas. (Top-Right) Rendered surface of the patient’s brain with the locations of subdural grid and strip electrodes.(Bottom-Left) Time courses of high-gamma power in four electrodes, with significant high-gamma activity observed in electrodes FG-2, FG-8, and STG-6. (Bottom-Right) Significant high-gamma power modulation during a picture naming task, recorded using intracranial EEG. See (Babajani-Feremi et el. 2019) for more details.

Related Publications:

[1] A. Babajani-Feremi, H. Pourmotabbed, W. A. Schraegle, C. S. Calley, D. F. Clarke, and A. C. Papanicolaou, "MEG language mapping using a novel automatic ECD algorithm in comparison with MNE, dSPM, and DICS beamformer," Front Neurosci, vol. 17, p. 1151885, 2023, doi: https://doi.org/10.3389/fnins.2023.1151885.

[2] R. Arya, A. Babajani-Feremi, A. W. Byars, J. Vannest, H. M. Greiner, J. W. Wheless, F. T. Mangano, and K. D. Holland, "A model for visual naming based on spatiotemporal dynamics of ECoG high-gamma modulation," Epilepsy Behav, vol. 99, p. 106455, Oct 2019, doi: https://doi.org/10.1016/j.yebeh.2019.106455.

[3] A. Babajani-Feremi, S. P. Fulton, C. M. Holder, A. F. Choudhri, F. A. Boop, and J. W. Wheless, "Localization of Expressive Language Cortex in a 2-Year-Old Child Using High-Gamma Electrocorticography,", Journal of Child Neurology, vol. 34, no. 13, pp. 837-841, Nov 2019, doi: https://doi.org/10.1177/0883073819863999.

[4] V. Youssofzadeh and A. Babajani-Feremi, "Mapping critical hubs of receptive and expressive language using MEG: A comparison against fMRI," Neuroimage, vol. 201, p. 116029, Nov 1 2019, doi: https://doi.org/10.1016/j.neuroimage.2019.116029.

[5] A. Babajani-Feremi, C. M. Holder, S. Narayana, S. P. Fulton, A. F. Choudhri, F. A. Boop, and J. W. Wheless, "Predicting postoperative language outcome using presurgical fMRI, MEG, TMS, and high gamma ECoG," Clin Neurophysiol, vol. 129, no. 3, pp. 560-571, Mar 2018, doi: https://doi.org/10.1016/j.clinph.2017.12.031.

[6] A. C. Papanicolaou, R. Rezaie, S. Narayana, A. F. Choudhri, F. Abbas Babajani, F. A. Boop, and J. W. Wheless, "On the relative merits of invasive and non-invasive pre-surgical brain mapping: New tools in ablative epilepsy surgery," Epilepsy Res, Jul 03 2017, doi: https://doi.org/10.1016/j.eplepsyres.2017.07.002.

[7] A. C. Papanicolaou, M. Kilintari, R. Rezaie, S. Narayana, and A. Babajani-Feremi, "The Role of the Primary Sensory Cortices in Early Language Processing," J Cogn Neurosci, vol. 29, no. 10, pp. 1755-1765, Oct 2017, doi: https://doi.org/10.1162/jocn_a_01147.

[8] A. Babajani-Feremi, "Neural Mechanism Underling Comprehension of Narrative Speech and Its Heritability: Study in a Large Population," Brain Topogr, vol. 30, no. 5, pp. 592-609, Sep 2017, doi: https://doi.org/10.1007/s10548-017-0550-6.

[9] A. Babajani-Feremi, S. Narayana, R. Rezaie, A. F. Choudhri, S. P. Fulton, F. A. Boop, J. W. Wheless, and A. C. Papanicolaou, "Language mapping using high gamma electrocorticography, fMRI, and TMS versus electrocortical stimulation," Clinical Neurophysiology, vol. 127, no. 3, pp. 1822–1836, 2016. https://doi.org/10.1016/j.clinph.2015.11.017.

[10] A. Babajani-Feremi, R. Rezaie, S. Narayana, A. F. Choudhri, S. P. Fulton, F. A. Boop, J. W. Wheless, and A. C. Papanicolaou, "Variation in the topography of the speech production cortex verified by cortical stimulation and high gamma activity," Neuroreport, vol. 25, no. 18, pp. 1411-7, Dec 17 2014, doi: https://doi.org/10.1097/WNR.0000000000000276.