This chapter in many ways resembles Chapter 7. This is mainly due to the parallels between learner language and aphasic language as two manifestations of less than competent language use. The general prediction of the Structural Theory regarding language breakdown is the same as for language acquisition: Aphasic output is predicted to be characterized by a lowered sensitivity to structural constraints. That is to say, brain damage or any other kind of neurological disorder is expected to reduce the capacity to unfold the structural representation, which is consequently flatter than in so-called normal language. The underlying assumption here is that the activation process is disrupted in aphasia (e.g., Ellis & Young, 1988; Haarmann & Kolk, 1991; Dell, Schwartz, Martin, Saffran, & Gagnon, 1997). If structural units cannot be properly activated, the structural representation will be impoverished and therefore relatively flat.