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This study examined the effects of dual task requirements on age differences in free recall performance. One thousand adults ranging in age between 35 and 80 years performed a word recall task alone and concurrently with a card-sorting task (at encoding, retrieval, or both). Age differences in memory performance were substantial under single task conditions, but after correcting memory performance under dual task conditions for differences in single task performance, age did not predict performance. These results do not support the hypothesis that reduced attentional capacity in old age is underlying age differences in episodic memory.

One experiment compared the effect of elaboration on enacted and non-enacted events. The commands were either presented in a basic form (e.g., "wave your hands") or in an enriched form. The commands were enriched by adding statements to the commands of how to perform the actions (e.g., "wave your hands as a conductor"). Free- and cued-recall data showed elaboration to have a dissociative effect on enacted and non-enacted events. Memory for the non-enacted events benefited from enrichment, whereas simple enacted events were remembered to a higher extent than complex enacted events. Lack of benefit from elaboration on memory of enacted events is suggested to be due to enactment leading to a sufficient degree of item-specific processing, and a negative effect of elaboration is suggested to occur when the way of manipulating item complexity decreases the familiarity of the actions. Familiarity ratings of the items by two independent groups of subjects supported this interpretation.

When subjects study a list of B items paired with A items and are tested for recognition of the B items alone, and then for recall of the B items given the A items as cues, B items that can be recalled frequently go unrecognised. The extent of this recognition failure is predictable from a function discovered by Tulving and Wiseman (1975), which relates the probability of recognising the recallable items to the probability of recognising all items. Two kinds of exceptions to this function have been discovered: encoding exceptions and retrieval exceptions. Very few observations of retrieval exceptions exist. Four experiments described in this article provide further evidence that such exceptions occur when the B items are categorised and the A items are the names of the categories. According to a contextual account of the function and exceptions to it, these retrieval exceptions occur because the information provided by the A-item cues can be largely retrieved from the B items in the recognition test; hence, as cues, the A items do not provide much different contextual information to that provided by the B items. By this account, the function is an empirical law; exceptions fall outside the range of this law and define its boundary conditions.

Enactment during the encoding of simple imperatives has been found to improve substantially performance on conceptually driven explicit-memory tests. In two experiments the effect of this manipulation on a conceptually driven implicit test (category association) was studied. A conceptually driven explicit test (free recall) was also included. In Experiment one three different study conditions (enactment with real objects, reading, and generation) were considered. In Experiment two there were two study conditions (enactment with imaginary objects and reading). Compared to reading, generation was found to improve the performance on both free recall and category association, whereas enactment affected free recall only. In a final experiment subjects imagined that they performed the tasks, and this manipulation was found to improve the memory performance on both tests. Taken together, this pattern of results is interpreted as suggesting that free recall and category association have a process in common that is sensitive to semantic processing at study (promoted by generation and imagery, but not by enactment), and that free recall involves a retrieval process in addition that is facilitated by a rich encoding environment (provided by enactment).

Two experiments addressed the influence of secondary task performance at encoding on recall of different features of subject-performed tasks (SPTs) involving objects (e.g., turn the wallet). In Experiment 1, memory for verbs and colors of objects was assessed, with object names serving as cues. In Experiment 2, object and color memory were assessed, with verbs serving as cues. Results from both experiments indicated a greater deterioration of memory performance under divided attention for verbal features than for colors. In addition, intention to remember did not affect performance for any feature in either experiment. The overall pattern of outcome is discussed relative to the view that encoding of verbal features of SPTs is more attention-demanding than encoding of physical task features, such as color.

The ability of patients with Alzheimer's disease (AD) to utilize semantic category cues in order to improve memory performance was examined. Categorizable lists of words or objects were presented under five different encoding conditions: (a) nouns, (b) objects, (c) objects with a semantic orienting question, (d) objects with self-generated motoric acts, and (e) objects with experimenter-instructed motoric acts. Subjects were asked to memorize the items for a free recall test, and were subsequently provided with the category names in a cued recall test. Mildly, moderately, and severely demented AD patients, and a group of normal older adults participated in the study. Results showed that normal older adults and mildly demented AD subjects were able to utilize cues to improve memory performance in all conditions. Moderately demented patients utilized cues in all conditions except in the verbal condition (condition [a]), whereas severely demented patients utilized cues only in the motoric condition (condition [e]). These results suggest that the ability to utilize category cues following a motoric encoding is preserved later in AD than the ability to utilize cues after a semantic encoding.