One thing we have learned about brain disorders is that they do not usually respect boundaries between the cortex and underlying white matter. Damage to one has knock-on effects on the other, even in conditions which may preferentially affect white matter, such as multiple sclerosis. But what are the implications of white matter damage? Could it be responsible for cognitive syndromes that are traditionally considered to result from cortical damage? The paper by Urbanski and colleagues1 in this issue of J Neurol Neurosurg Psychiatry examines the possibility that disconnecting distributed cortical networks might play a critical role in the syndrome of unilateral neglect following stroke (see page 598).

These authors used diffusion tensor imaging (DTI), a new imaging method which …