The conditional-recency dissociation is confounded with nominal recency: should unitary models of memory still be devaluated?

The conditional-recency dissociation between immediate and delayed free recall FR; Farrell (Journal of Experimental Psychology: Learning, Memory, and Cognition, 36, 324-347, 2010) has critical implications regarding the prolonged debate between unitary and dual-store models of memory. In immediate FR, when the availability of items is controlled for, the recency of the final list item increases across the first few output positions. No such increase is found in delayed FR, with a trend in the opposite direction. This dissociation challenges temporal context TCM; Howard & Kahana (Journal of Mathematical Psychology, 46, 269-299, 2002) and distinctiveness SIMPLE; Brown, Neath, & Chater (Psychological Review, 114, 539-576, 2007) unitary models of memory and suggests the involvement of a short-term buffer in immediate FR. We show that this dissociation is confounded with the different magnitudes of nominal recency (i.e., the prevalence of the final list item) found in immediate as compared to delayed FR. By reshuffling output orders and comparing the empirical results to those of a null hypothesis of no output-order effect, we controlled for the greater prevalence of the final list item that has been observed in immediate FR. Under this control, we found no evidence for a dissociation in the tendency to recall the final list item across output positions. This finding suggests that the conditional-recency dissociation imposes no new constraint on unitary models of memory. More generally, we demonstrate how biases that influence measures of output-order tendencies (e.g., conditional recency) can be controlled for, thus yielding "purer" measures of these variables.