Functional magnetic resonance imaging (fMRI) was used to determine the pattern of receptive language lateralization in 11 healthy children (7 girls, 4 boys; mean age, 8.5 yrs) at Children’s National Medical Center, George Washington School of Medicine, DC. All were right-handed, with strong preference for the right hand, and all had high average-to-superior intelligence. Functional and structural MR images were obtained during silent naming of objects presented auditorily in a descriptive phrase (eg. “long yellow fruit” for “banana”). Strong activation occurred bilaterally, with greater activation in the left hemisphere, especially in superior and middle temporal gyri. Group analysis also revealed other areas of activation, including the left cuneus, left inferior temporal gyrus, prefrontal area, and left fusiform and lingual gyri. Individual scans showed additional activation in the left frontal lobe. Asymmetry indices showed lateralization to the left inferior frontal gyrus, middle frontal gyrus, and the Wernicke area. [1]

COMMENT. Hemispheric lateralization and left hemisphere language dominance for auditory comprehension is present in healthy children at 8 years of age, similar to that of adults.

Language dominance in partial epilepsy patients is identified using an fMRI reading task, also at the Children’s National Medical Center, Washington, DC [2]. Of 30 patients, ages 8 to 56 years, with temporal lobe epilepsy, 25 were left dominant, 2 right, one bilateral, and 2 undetermined. Results of intracarotid amobarbital Wada test and fMRI agreed in most patients.

The Wada test and its possible replacement with fMRI are discussed in an editorial [3]. Only “when a paradigm or battery of fMRI paradigms can be validated for identification of language regions that should be excluded from excision, and for postoperative memory function, We are almost there.”