Choosing sides: on the variability of language lateralization in normal subjects.

We report test-retest reliabilities and individual asymmetries for a lateralized lexical decision task. Although acceptable reliability was found for word recognition, most subjects did not show statistically significant asymmetries, despite a robust right visual field group advantage. Inter-subject variability was unrelated to sex, handedness, or familial sinistrality. We offer some suggestions as to why these differences are to be expected in the study of normal populations.