Associative Unitization via Semantic Relatedness Benefits Episodic Recognition of Component Elements

It has been proposed that although unitization benefits associative episodic memory, such benefits may exact a cost of poorer subsequent memory for the individual component elements forming these associations. However, unitization effects on item memory may be a function of whether items were unitized in a top-down fashion (i.e., through encoding instructions) or in a bottom-up fashion (through inherent semantic relationships between the associated items). We hypothesized that semantic relatedness unitization would benefit item recognition due to processing fluency that affords availability of more encoding resources. In two experiments, we tested how relatedness unitization of object pictures at encoding affected subsequent item recognition. The first experiment used a between-subject inclusion/exclusion paradigm, while the second experiment used a within-subject three-alternative choice recognition test. Results of both experiments revealed that semantic relatedness unitization benefited item memory. However, both accuracy patterns and error analyses indicated that such relatedness-based unitization improved memory for an item’s gist (i.e., its categorical identity), but not for its visual details. This indicates that that associative relatedness at encoding strengthens representations of the semantic identity of individual stimuli, but not necessarily of their perceptual details, possibly because of enhanced semantic elaboration at encoding.

The facilitation effect of associative and semantic relatedness in word recognition

In this study we addressed three issues concerning semantic and associative relatedness between two words and how they prime each other. The first issue is whether there is a priming effect of semantic relatedness over and above the effect of associative relatedness. The second issue is how difference in semantic overlap between two words affects priming. In order to specify the semantic overlap we introduce five relation types that differ in number of common semantic components. Three relation types (synonyms, antonyms and hyponyms) represent semantic relatedness while two relation types represent associative relatedness, with negligible or no semantic relatedness. Finally, the third issue addressed in this study is whether there is a symmetric priming effect if we swap the position of prime and target, i.e. whether the direction of relatedness between two words affects priming. In two lexical decision experiments we presented five types of word pairs. In both experiments we obtained stronger facilitation for pairs that were both semantically and associatively related. Closer inspection showed that larger semantic overlap between words is paralleled by greater facilitation effect. The effects did not change when prime and target swap their position, indicating that the observed facilitation effects are symmetrical. This outcome complies with predictions of distributed models of memory.

Acquisition and Clustering in Multiple-Trial Free Recall as a Function of Meaningfulness of Dissyllables

Lists of 10 dissyllables varying in meaningfulness were presented to subjects in a multiple-trial free recall task. Measures of recall and clustering showed superior recall and greater amounts of clustering for the high-meaningful list than for the low-meaningful list. Differential item integration and associative relatedness were mechanisms employed to explain the differences.

Acoustic and Associative Coding in Short-Term Memory

Short lists of word-digit pairs were presented to 456 college student subjects. One of the words was repeated as a memory probe either immediately after list presentation or after a short rehearsal interval. The stimulus words were either acoustically identical or associatively related (UP, DOWN). Both acoustic identity and associative relatedness produced a memory decrement which decreased with rehearsal. One interpretation of these results is that the primary memory trace is a multiple-dimension one and that, given time, subjects can recover non-acoustic information from it. The data also indicate that the “fate” over time is different for acoustically similar and associatively related items.