Strengthening the activation of unconsciously activated memories

Reading a word activates a set of associated words-for example, reading CAB activates car, driver, and other associates. This research was conducted to determine whether the unconscious activation of these associates adds activation to other associates in the same set. Words were studied, and recall was tested with cues comprised of associates directly activated by the target. On the basis of preexisting links, the associates serving as test cues also received strong (e.g., car) or weak (e.g., driver) additional inputs from other associates in the set. Cues receiving stronger inputs from other associates were more effective, indicating that unconsciously activated associates strengthen one another. This effect declined when conditions disrupted the retrieval of context features linked to the episode. Attending to another task during or after study or receiving implicit test instructions decreased the effects of input from other associates. Importantly, disruptions affected input from other associates more than direct input from the target, suggesting that the influence of context wanes as the links in the network become more distant.     

Implicit processing in the cued recall of young and old adults.

Two cued recall experiments were reported in which younger and older subjects studied target words varying in number of preexperimental associates. In Experiment 1, targets were studied in either the absence or presence of meaning-related context cues, with recall always prompted by the cues. In the absence of context, words with smaller sets of associates were easier to recall than those with larger sets, but this effect was reduced for older subjects. The presence of a study context cue facilitated recall and eliminated the effect of associative set size for both ages. In Experiment 2, targets were studied and tested in the presence of unrelated words. In this situation, words with smaller sets of associates were less likely to be recalled than words with larger sets; again the effect was reduced for older subjects. The results are interpreted as an age decrement in processing implicitly activated information.     

Aging and the stability of activation and sampling in cued recall

Age effects in cued recall were investigated as a function of activation and sampling of preexisting associates of the test cue. Young adults, community-dwelling elderly, and elderly patients studied lists of unrelated words and were tested with extralist cues. Preexperimental strength between test cues and studied words was manipulated to discern differences in activation, and normative size of the set of associates was manipulated to discern differences in sampling. Test delay and prior testing were also manipulated in Experiment 1. Although large age effects were found with phonemic and taxonomic test cues, young and older subjects showed comparable effects of strength and set size, suggesting that age effects were not due to activation and sampling differences. Test delay and prior testing also had comparable effects. Implications for age effects in episodic cued recall are discussed.     

Are implicitly activated associates selectively activated?

What constitutes a word’s associative past? Words differ in how many associates they activate in memory and, following a brief encounter, those with fewer associates are more likely to be recalled in the presence of related cues. The issue addressed in the present article is whether associative set size effects are produced through the selective activation of strong associates or through the activation of both strong and weak associates. The set size of the strongest associates was varied factorially with the set size of the associates of these associates. We assume that associate set size indexes a word’s weaker associates. Experiments 1 and 2 showed that recall varied inversely with both target and associate set sizes. Such results held over variations in study time and participant age. Experiment 3 showed that weak associates of the target had a greater effect on recall when there were more connections among the strongest associates in the set. The findings suggest that activation is not strength selective but includes both weak and strong associates.     

How does delayed testing reduce effects of implicit memory: Context infusion or cuing with context?

Studying a word implicitly activates related associates that affect its recall in the extralist cuing task. Recall is more likely when one of these associates becomes the test cue and when other associates of the studied word activate this associate. Context disruptions occurring between study and test reduce these effects, suggesting that implicitly activated memories are linked to context. The context infusion hypothesis assumes that context information spreads throughout a word's associative network during study, decreasing with distance from the studied word. Interactive cuing assumes that context is linked only to the studied word and that recall is based on retrieving information from the test cue and the context. The infusion hypothesis predicts that effects of disruptions will depend on link distance whereas interactive cuing predicts that distance will have no effect. The experiments evaluate these explanations by manipulating target-to-cue strength, associate-to-cue strength, and context disruption. Experiment 1 varies disruption by testing under the same or different conditions (room, modality, experimenter). Experiment 2 tests recall immediately or after 5 m, 10 m, or 20 m of multiplication. The results are inconsistent with context infusion and support the interactive cuing explanation.     

Generation effects in free recall: further support for a three-factor theory

A framework is presented that helps explain and predict generation effects in free recall (for between-subjects manipulations of generating vs. reading). When the targets share common features and when that shared information is salient to subjects, subjects will exploit that information to help generate the target items. This produces more relational processing among the targets (relative to reading), enhancing free recall. Consistent with this idea, when shared information (among targets) was salient, generation effects in free recall were found under encoding conditions that can disrupt generation effects in cued recall (e.g., pairing targets with unrelated cues). Further, within the same list, generation effects emerged in free recall for targets that were processed after shared information became evident but not for targets processed prior to the availability of the shared information. In recognition, generation effects were found for targets regardless of when they were processed.     

Cue set size effects: Sampling activated associates or cross-target interference?

Previous findings indicate that test cues linked to more associates (more knowledge) produce lower levels of recall than cues with fewer associates. One hypothesis attributes this effect to cross-target interference arising during retrieval on the assumption that cues with more associates are more likely to be indirectly connected to studied words other than the target. Another attributes the effect to sampling associates of the cue on the assumption that the probability of sampling the target declines as more associates are activated. Findings from four experiments showed that recall varied with cue set size, and, more importantly, that cue set size affected recall independently of the interference produced by cross-target connections. These results were interpreted as supporting a model that attributes cue set size effects to sampling processes associated with the intersection of the test cue and its associates with the target and its associates.     

Effects of the timing and identity of retrieval cues in individual recall: an attempt to mimic cross-cueing in collaborative recall

Inhibitory effects in collaborative recall have been attributed to cross-cueing among partners, in the same way that part-set cues are known to impair recall in individuals. However, studies of part-set cueing in individuals typically involve presenting cues visually at the start of recall, whereas cross-cueing in collaboration is likely to be spoken and distributed over time. In an attempt to bridge this gap, three experiments investigated effects of presenting spoken part-set or extra-list cues at different times during individual recall. Cues had an inhibitory effect on recollection in the early part of the recall period, especially when presented in immediate succession at the start of recall. There was no difference between the effects of part-set and extra-list cues under these presentation conditions. However, more inhibition was generated by part-set than extra-list cues when cue presentation was distributed throughout recall. These results are interpreted as suggesting that cues presented during recall disrupt memory in two ways, corresponding to either blocking or modifying retrieval processes. Implications for explaining and possibly ameliorating inhibitory effects in collaborative recall are discussed.     

Effects of the timing and identity of retrieval cues in individual recall: An attempt to mimic cross-cueing in collaborative recall

Inhibitory effects in collaborative recall have been attributed to cross-cueing among partners, in the same way that part-set cues are known to impair recall in individuals. However, studies of part-set cueing in individuals typically involve presenting cues visually at the start of recall, whereas cross-cueing in collaboration is likely to be spoken and distributed over time. In an attempt to bridge this gap, three experiments investigated effects of presenting spoken part-set or extra-list cues at different times during individual recall. Cues had an inhibitory effect on recollection in the early part of the recall period, especially when presented in immediate succession at the start of recall. There was no difference between the effects of part-set and extra-list cues under these presentation conditions. However, more inhibition was generated by part-set than extra-list cues when cue presentation was distributed throughout recall. These results are interpreted as suggesting that cues presented during recall disrupt memory in two ways, corresponding to either blocking or modifying retrieval processes. Implications for explaining and possibly ameliorating inhibitory effects in collaborative recall are discussed.     

The self-choice effect from a multiple-cue perspective

The self-choice effect refers to the fact that self-chosen items are remembered better than experimenter-assigned items (Takahashi, 1991). The present study investigated the hypothesis that (a) response choice involves relational processing as activation of both target and context items, and (b) such activated context items are effective as potential retrieval cues for recall of target items. In the experiment, participants chose (choice condition) or were assigned (force condition) a target to remember for each trial. Prior to free recall of the target items, context words, related new words, or unrelated words were presented in a recognition task as potential retrieval cues. The results of a subsequent free recall test indicated that the incidental cues were more effective in the choice condition than in the force condition. Also, recognition resulted in a greater rate of successfully recognized context words at the cost of increasing falsely recognized related new words in the choice condition in comparison with the force condition. These results indicated that response choice activates context items at encoding, which operate as potential retrieval cues for recall of target items. Such cuing mechanisms operative in the self-choice effect are consistent with the multiple-cue theory proposed by Soraci et al. (1994; see also Soraci et al., 1999) for generative processing.     

Selective access in cued recall: The roles of retrieval cues and domains of encoding

The purpose of these experiments was to determine whether retrieval access in cued recall can be selectively restricted to a single domain of encoding when information has been encoded within two domains as different as word sound and word meaning. In Experiment 1, the subjects studied pairs of rhyming words differing in rhyme set size under verbal-repetition or interactive-imagery instructions. Recall was cued with study-context rhymes, with extralist rhymes, or with extralist associates. The results indicated that rhyme set size and instructional effects were found no matter how recall was cued, indicating that both domains of encoding were always accessed. In Experiment 2, potential effects of study time and overt naming of the test cues were explored. These results indicated that both domains of encoding were accessed, except when long study times were available and subjects did not have to name the rhyme test cues. Rhyme set-size effects were eliminated under these conditions, suggesting that selective access to encoded meaning is possible in cued recall. Retrieval access in this task appears to be more controlled by domains of encoding than by information directly available in the cue, and access to encoded information can be restricted to a single domain.     

Part-list cuing and the dynamics of false recall

False recall of an unpresented critical word after studying its semantic associates can be reduced substantially if the strongest and earliest-studied associates are presented as part-list cues during testing (Kimball & Bjork, 2002). To disentangle episodic and semantic contributions to this decline in false recall, we factorially manipulated the cues’ serial position and their strength of association to the critical word. Presenting cues comprising words that had been studied early in a list produced a greater reduction in false recall than did presenting words studied late in the list, independent of the cues’ associative strength, but only when recall of the cues themselves was prohibited. When recall of the cues was permitted, neither early-studied nor late-studied cues decreased false recall reliably, relative to uncued lists. The findings suggest that critical words and early-studied words share a similar fate during recall, owing to selective episodic strengthening of their associations during study.     

Overriding age differences in attentional capture with top-down processing

Two experiments investigated the influence of top-down information on adult age differences in the ability to search for singleton targets using spatial cues. In Experiment 1, both younger and older adults were equally able to use target-related top-down information (target feature predictability) to avoid attentional capture by uninformative (25% valid) cues. However, during informative (75% valid) cue conditions, older adults demonstrated less efficient use of this cue-related top-down information. The authors extended these findings in Experiment 2 using cues that were either consistent or inconsistent with top-down feature settings. Results from this second experiment showed that although older adults were capable of avoiding attentional capture when provided with top-down information related to target features, capture effects for older adults were notably larger than those of younger adults when only bottom-up information was available. The authors suggest that older adults' ability to use top-down information during search to avoid or attend to cues may be resource-limited.     

Long-term retention of a theatrical script by repertory actors: the role of context.

Four actors were requested to perform Sartre's No Exit after a retention interval of more than 5 months. Their recall of the play was studied either with the spatial and visual contextual cues normally available during a performance or without such cues. Total recall was still considerable, equalling 85%. The number of paraphrases of, and inferences on, the original text was however quite large (32%), suggesting that the actors had learned their lines according to their meaning rather than as a result of rote memorisation. The context manipulation showed that actors' recall is facilitated by the availability of spatial-visual information, but only to a limited extent. The relative importance of textual and contextual cues in the long-term retention of a play is discussed.     

Lexical and semantic search in cued recall, fragment completion, perceptual identification, and recognition

Search processes in word-stem cued recall, fragment completion, perceptual identification, and recognition are contrasted. These retention tests involve letters as cues, but the lexical characteristics of these cues vary considerably. In word-stem cued recall, ending letters are presented as recall cues for studied targets (e.g., ONEY as a cue for HONEY). In fragment completion, the test cues consist of letters and spaces (e.g., HO__Y); in perceptual identification, they consist of letter features that survive the mask; and in recognition, they consist of all the letters of the studied word (e.g., HONEY). These differences in retention tests and lexical characteristics were evaluated by manipulating three variables with known effects in cued recall: (a) the presence of study context words emphasizing lexical information, (b) lexical set size corresponding to the number of words that fit the letter cue, and (c) meaning set size corresponding to the number of meaningful associates linked to the studied targets. The results indicated that (a) the presence of study contexts emphasizing lexical information reduced accuracy and response time equally in all tasks, (b) larger lexical set sizes reduced accuracy and response time in all tasks except recognition, and (c) larger meaning set size reduced accuracy in cued recall but not in the other tasks. Lexical search appears to be a significant component process in word-stem cued recall, fragment completion, and identification. Searching through meaning-related concepts encoded during study is a significant component process only in cued recall.     

Cue familiarity but not target retrievability enhances feeling-of-knowing judgments.

Two hypotheses concerning people's ability to predict later memory performance for unrecalled items were investigated. The target retrievability hypothesis states that feeling-of-knowing judgments (FKJs) are based on partial target information; and the cue familiarity hypothesis asserts that they are based on recognition of the cues. In Experiments 1 and 2, subjects either generated or read the targets of paired associates. Half of the cues had been primed in a pleasantness-rating task. The generation manipulation increased recall but had no effect on FKJs. Cue priming had no effect on recall but increased FKJs. In Experiment 3, using general information questions, primed after the initial recall attempt, both cue and target priming increased FKJs. Experiment 4, which remedied difficulties in Experiment 3, showed no effect of target priming whereas cue priming increased FKJs. The results favor the cue familiarity hypothesis.     

Encoding context and retrieval conditions as determinants of the effects of natural category size

Studying a familiar word activates its associates in long-term memory. In the present experiments we manipulated the number of associates activated by words studied in the presence of unrelated context words, meaningfully related context words, or in the absence of modifying context words. Memory was tested by either cued or free recall. The results showed that the number of directly activated associates can facilitate, have no effect, or disrupt recall for studied words. The direction and magnitude of the effects of number of activated associates is shown to be determined by the encoding/retrieval context. Implications for the distinction between episodic and semantic memory are discussed.     

Retrieval of Episodic Information From Memory: Comparisons Among 3- and 4-Year-Olds, 7- and 8-Year-Olds,and Adults

Young children's and adults' recall of episodic information was explored in 4 experiments. The task required participants to recall a target noun presented as the last item of a 4-noun string of related (either categorically or thematically) or unrelated words. Providing all 3 preceding nouns or a subset of them cued recall. Experiment 1 found that 7- and 8-year-old children's recall was better with pictures as opposed to text, and children showed performance equal to adults with thematically related pictorial stimuli. Using pictorial stimuli, Experiment 2 showed that the number of cues present at retrieval affected 7- and 8-year-olds' recall. Experiments 3 and 4 tested recall of episodic information in 3- and 4-year-olds using pictorial stimuli. The results suggested that young children also have access to episodic information in memory and the number of cues present at retrieval influenced recall. The findings are discussed in the context of children's memory for events.     

Aging and semantic cueing during learning and retention of verbal episodic information

The purpose of this study was to determine the effectiveness of semantic cues provided at encoding and during retention for older adults' memory. For the California Verbal Learning Test-II, participants received semantic or nonsemantic cues that were varied across groups at encoding and during the retention interval. Provision of a semantic cue at encoding led to greater semantic clustering at learning, but not increased recall performance. Providing a semantic cue during the retention interval led to better delayed free recall and greater semantic clustering. No group differences in recall or semantic clustering were found at delayed cued recall. The current findings suggest that semantic cues can be beneficial for recalling unstructured information when administered during the retention interval.     

Release from generation failure: The role of study list structure

Three experiments, using the original encoding-specificity paradigm, investigated the role of study list structure in producing Higham and Tam's (2005) generation failure effect. Generation failure occurs when cued recall performance for strong, extralist cues is worse than target production in a control group that is given no study list but is instead required merely to generate responses to the same test cues. In the present study, generation failure was replicated in Experiment 1, and Experiment 2 demonstrated that strong, extralist cues were more likely to elicit targets in pure generation groups when participants had studied a list of strong associates than when they had studied a list of weak ones. In Experiment 3, participants were released from generation failure when a study list of moderate associates was used and the cue-to-target associative strength was equated between the reinstated- and extralist-cue conditions. Together, these results suggest that generation failure is partly attributable to participants' searching inappropriate domains that, though consistent with the study list structure, are unlikely to contain targets.