Three Rights Don't Make a Left: Right Hemispheric Language Lateralization in a Right-Handed Bilingual Child with Right Frontal Focal Cortical Dysplasia
Abstract number :
2.294
Submission category :
11. Behavior/Neuropsychology/Language / 11B. Pediatrics
Year :
2021
Submission ID :
1826609
Source :
www.aesnet.org
Presentation date :
12/5/2021 12:00:00 PM
Published date :
Nov 22, 2021, 06:55 AM
Authors :
Sara Siddiqui, MD - University of Texas-Austin, Dell Medical School; Nancy Nussbaum, PhD, ABPP - Associate Professor, Neuropsychologist, Department of Neurology, University of Texas-Austin, Dell Medical School; Rosario DeLeon, PhD - Assistant Professor, Neuropsychologist, Department of Neurology, University of Texas-Austin, Dell Medical School; Dave Clarke, MD - Professor and Chair of the Comprehensive Epilepsy Program, Department of Neurology and Department of Pediatrics, University of Texas-Austin, Dell Medical School
Rationale: Studies estimate that 90-95% of persons are right-handed, and 95% of right-handers have left hemispheric language representation. 85% of left-handers (5-10% of the population) are also left hemisphere dominant. Bilateral language dominance predominates in both right and left handers that are not left language dominant. Few patients are therefore right hemisphere dominant for language only. Bilingual individuals add complexity, with the increased possibility of atypical, or bilateral, language representation. We present a case report of a 3-year-old bilingual male with right hemispheric language lateralization, right-handedness, and right frontal focal cortical dysplasia.
Methods: The patient was a bilingual (Spanish and English) three-year-old right-handed male with medically-refractory focal epilepsy undergoing phase 1 evaluation. MRI (3T), continuous video EEG monitoring, MEG, comprehensive neuropsychological testing, and functional MRI were performed. Sedated MEG included a paradigm for auditory/receptive English language processing. Sedated functional MRI evaluated auditory/receptive language processing (English and Spanish). Comprehensive neuropsychological testing was performed.
Results: 3T MRI showed right frontal dysplasia of the right superior and middle frontal gyri. EEG demonstrated frequent interictal epileptiform discharges and a total of thirteen typical seizures arising from the right fronto-centro-parietal perirolandic region with field extending frontally and parasagitally, with concordant semiology of left arm clonus and left facial clonus without loss of awareness. MEG was suggestive of English auditory/receptive language processing lateralized to the right hemisphere. Functional MRI showed bilateral activation (right greater than left) for auditory/receptive language in Spanish, and right activation in English. Neuropsychological testing indicated broadly average cognitive skills; average receptive and low average expressive language (Spanish); and a right-hand preference for functional and graphomotor tasks. Notably, the patient demonstrated better left-hand dexterity on a pegboard test.
Conclusions: This case is a valuable addition to the literature due to the age of the patient (3 years old), bilingual language (Spanish and English), right handedness, right hemispheric language dominance, and right frontal dysplasia. We demonstrated the viability of collecting functional motor and language data using passive stimulation in MEG and fMRI, and convergent validity was shown between these methods with a young bilingual child. The significance of these findings is that this case expands our understanding of atypical language organization in bilingual children. This data allows for a more comprehensive discussion of benefits and risks in the surgical decision making process.
Funding: Please list any funding that was received in support of this abstract.: No funding was received in support of this abstract.
Behavior