The dual origin of lexical perseverations in aphasia: Residual activation and incremental learning.

Lexical perseveration, the inappropriate repetition of a previous response, is common in aphasia. Two underlying mechanisms have been proposed: residual activation and incremental learning. Previous attempts to differentiate the two have relied on experimental paradigms that encourage semantically related errors and analysis techniques designed to detect perseverations over short distances, resulting in a bias towards detecting short-lag, semantically related perseverations that both mechanisms can account for.

To select or to wait? Response to the commentaries.

In [Nozari, N., & Hepner, C. R.

To select or to wait? The importance of criterion setting in debates of competitive lexical selection.

Competitive accounts of lexical selection propose that the activation of competitors slows down the selection of the target. Non-competitive accounts, on the other hand, posit that target response latencies are independent of the activation of competing items. In this paper, we propose a signal detection framework for lexical selection and show how a flexible selection criterion affects claims of competitive selection.