Atypical Representation of Hemispheric Language Dominance in a Pediatric Epilepsy Surgery Candidate – A Case Study

Sofia Iglesias Medina, Nicklaus Children's Hospital, Miami, United States
Hala El Bahraoui, Nicklaus Children's Hospital, Miami, United States
Kayleen Ball, Nicklaus Children's Hospital, Miami, United States


Little is known about first and second language laterality on bilingual candidates for brain surgery. Recent studies have shown that early bilingualism is associated with greater bilateral hemisphere involvement. Similarly, early proficient bilinguals have shown more pronounced right hemisphere activation. In this case study, we explore the atypical representation of hemispheric language dominance in a pediatric epilepsy pre-surgical case.

Participants and Methods:

Patient is a 15-year-old right-handed Hispanic male. He is English/Spanish bilingual and a sequential language learner. Patient presents with intractable epilepsy (independent right frontotemporal and left temporal epileptiform discharges) and a history of an arachnoid cyst overlying the parasagittal aspect of the right frontal lobe. Neuropsychological evaluation during the pre-surgical evaluation included: recalling sentences, children’s auditory and visual naming tests, WASI-II, ChAMP, Verbal fluency, Color-Word Interference, Beery VMI, Grooved Pegboard and various social-emotional questionnaires. Pertinent medical tests were also performed by the medical team (vEEG, fMRI, PET scan, Brain MRI, and DTI).


Evidence of deficits in auditory verbal naming, recalling sentences, category verbal fluency, as well as visual/verbal memory and learning was suggestive of bilateral temporal dysfunction.  Evidence of phonemic verbal fluency and bilateral fine motor speed and dexterity impairments (left greater than right) was also suggestive of frontal involvement. These findings were consistent with imaging and EEG findings. However, dominant frontal and temporal involvement was noted given deficits in fine-motor speed and dexterity, verbal fluency, verbal memory, auditory/visual naming abilities and sentence repetition abilities. Patient’s right-handedness and history of later seizure onset in the context of solidly average nonverbal reasoning abilities likely indicates left hemispheric dominance. On the other hand, fMRI findings (performed with an English paradigm) were suggestive of right hemispheric dominance due to bilateral right greater than left activation of the arcuate fasciculus, receptive/expressive Wernicke, and Broca.


Recent literature has demonstrated that surgical bilingual candidates had smaller left hemisphere laterality (i.e., more volume of activation in the right hemisphere) similar to this case. A working theory is that bilinguals recruit additional areas of the right hemisphere for language. Thus, there is an overlapping and separate cortical representation of language. Atypical cases have also been recorded with different hemispheric laterality patterns in each language. Hence, a small proportion of bilingual clinical cases may have different laterality patterns in Language 1 versus Language 2. Of note, testing was not completed in Spanish with this patient given limitations of time, seizures during admission and predominant English academic instruction. Therefore, it is critical to map all languages proficiently spoken by surgical candidates. It is also important to create a model of care where bilingual pre-surgical patients can be tested in both languages prior to surgery.

Category: Epilepsy/Seizures

Keyword 1: epilepsy / seizure disorders
Keyword 2: bilingualism/multilingualism
Keyword 3: neuropsychological assessment