Case report of a massive congenital left hemisphere lesion: Support for the crowding hypothesis?

We report the case of a 39‐year‐old woman with a massive congenital left hemisphere lesion whose neuropsychological performance conforms inconsistently to expectations based on the crowding hypothesis. Indeed, rather than indicating an exclusive crowding of functions normally associated with the right hemisphere, her pattern of deficit is suggestive of subtle left hemisphere dysfunction (the site of the structural lesion) in the context of preserved language function, along with subtle right hemisphere dysfunction. However, the most striking aspect of this case is the overall preservation of function. The relative deficits are so subtle (with the exception of the fused dichotic listening performance) that, in the absence of prior knowledge regarding the lesion, many would have described said deficits as simply manifestations of individual variation.