A comparison of conscious and automatic memory processes for picture and word stimuli: a process dissociation analysis

Four experiments were conducted to evaluate explanations of picture superiority effects previously found for several tasks. In a process dissociation procedure (Jacoby, 1991) with word stem completion, picture fragment completion, and category production tasks, conscious and automatic memory processes were compared for studied pictures and words with an independent retrieval model and a generate-source model. The predictions of a transfer appropriate processing account of picture superiority were tested and validated in "process pure" latent measures of conscious and unconscious, or automatic and source, memory processes. Results from both model fits verified that pictures had a conceptual (conscious/source) processing advantage over words for all tasks. The effects of perceptual (automatic/word generation) compatibility depended on task type, with pictorial tasks favoring pictures and linguistic tasks favoring words. Results show support for an explanation of the picture superiority effect that involves an interaction of encoding and retrieval processes.     

Does a time-monitoring deficit influence older adults' delayed retrieval shift during skill acquisition?

The authors evaluated age-related time-monitoring deficits and their contribution to older adults' reluctance to shift to memory retrieval in the noun-pair lookup (NP) task. Older adults (M = 67 years) showed slower rates of response time (RT) improvements than younger adults (M = 19 years), because of a delayed strategy shift. Older adults estimated scanning latencies as being faster than they actually were and showed poor resolution in discriminating short from long RTs early in practice. The difference in estimated RT for retrieval and scanning strategies predicted retrieval use, independent of actual RT differences. Separate scanning and recognition memory tasks revealed larger time-monitoring differences for older adults than in the NP task. Apparently, the context of heterogeneous RTs as a result of strategy use in the NP task improved older adults' accuracy of RT estimates. RT feedback had complex effects on time-monitoring accuracy, although it generally improved absolute and relative accuracy of RT estimates. Feedback caused older adults to shift more rapidly to the retrieval strategy in the NP task. Results suggest that deficient time monitoring plays a role in older adults' delayed retrieval shift, although other factors (e.g., confidence in the retrieval strategy) also play a role.     

Automatic processing influences free recall: converging evidence from the process dissociation procedure and remember-know judgments

Dual-process theories of retrieval suggest that controlled and automatic processing contribute to memory performance. Free recall tests are often considered pure measures of recollection, assessing only the controlled process. We report two experiments demonstrating that automatic processes also influence free recall. Experiment 1 used inclusion and exclusion tasks to estimate recollection and automaticity in free recall, adopting a new variant of the process dissociation procedure. Dividing attention during study selectively reduced the recollection estimate but did not affect the automatic component. In Experiment 2, we replicated the results of Experiment 1, and subjects additionally reported remember–know–guess judgments during recall in the inclusion condition. In the latter task, dividing attention during study reduced remember judgments for studied items, but know responses were unaffected. Results from both methods indicated that free recall is partly driven by automatic processes. Thus, we conclude that retrieval in free recall tests is not driven solely by conscious recollection (or remembering) but also by automatic influences of the same sort believed to drive priming on implicit memory tests. Sometimes items come to mind without volition in free recall.     

Level of processing and the process-dissociation procedure: Elusiveness of null effects on estimates of automatic retrieval

We describe two experiments that used the process-dissociation procedure to investigate the effects of level of processing on estimates of controlled and automatic retrieval processes in word-stem completion tasks. Despite our best endeavours, we found the null effect of level of processing on estimates of automatic retrieval reported by Toth, Reingold, and Jacoby (1994) elusive. Estimates of automatic retrieval were not independent of level of processing but inversely related to it. In part, the reason was that, following deeper levels of processing, instructions to exclude recollected words led to floor effects. But the inverse relationship persisted even when floor effects were avoided. Only participants who were not given strict instructions in the exclusion task–and who also qualified as lax responders based on answers in a structured post-test interview–showed no effect of level of processing on estimates of automatic retrieval. This null effect apparently occurred because these participants failed to exclude words that they in fact recollected from the study list. This finding violates the critical assumption that in this task participants exclude recollected words. The results are therefore paradoxical. Successful replication of the null effect occurred only under conditions that preclude the very use of the procedure. This paradox has important implications for views on how consciousness should be conceived in relation to memory.     

Upper and lower limb reciprocal tapping: evidence for gender biases

According to D. Kimura's (2000) interpretation of the hunter-gatherer hypothesis, men are better at targeting tasks and women are better at fine-motor tasks because of their evolutionary experiences. The author applied that hypothesis to a lower limb pointing task, a task uninfluenced by hunting and gathering experience throughout history. Participants (39 women, 35 men) completed the P. M. Fitts (1954) task by using both their dominant right hand and foot. Results suggested that for both the upper and lower limbs, men move faster, particularly for the more difficult tasks. The hunter-gatherer hypothesis does not predict those data; rather, linear regression data suggest that gender differences in movement strategies affect motor performance. The author proposes that men and women preferentially adopt distinct strategies emphasizing speed for men and accuracy for women.     

意向保持间隔对时间性前瞻记忆的影响

通过两个实验来探讨意向保持间隔对时间性前瞻记忆的影响。实验一仅通过嵌入前瞻目标的背景任务来操纵保持间隔,实验二通过在背景任务之前加入不同时长的填充任务来改变意向保持间隔。结果发现,(1)背景任务中的保持间隔越长,前瞻记忆成绩越差;(2)背景任务中的保持间隔和填充任务的时长对前瞻记忆的影响存在交互作用。成绩最好的为15min-2min组,最差的为15min-15min组。结果表明,背景任务和填充任务阶段对于个体保持前瞻意向可能有不同的功能。     

The role of working memory capacity in multiple-cue probability learning

Multiple-cue probability learning (MCPL) involves learning to predict a criterion when outcome feedback is provided for multiple cues. A great deal of research suggests that working memory capacity (WMC) is involved in a wide range of tasks that draw on higher level cognitive processes. In three experiments, we examined the role of WMC in MCPL by introducing measures of working memory capacity, as well as other task manipulations. While individual differences in WMC positively predicted performance in some kinds of multiple-cue tasks, performance on other tasks was entirely unrelated to these differences. Performance on tasks that contained negative cues was correlated with working memory capacity, as well as measures of explicit knowledge obtained in the learning process. When the relevant cues predicted positively, however, WMC became irrelevant. The results are discussed in terms of controlled and automatic processes in learning and judgement.     

Automatic Priming Effects for New Associations in Lexical Decision and Perceptual Identification

Information storage in semantic memory was investigated by looking at automatic priming effects for new associations in two experiments. In the study phase, word pairs were presented in a paired-associate learning task. Lexical decision and perceptual identification were used to examine priming effects during and after the study phase. There was automatic priming for new associations. The priming effect was greatly reduced when different semantic tasks were used at study and test compared to when identical tasks were used at study and test. The results show that new associations in semantic memory can be accessed automatically but are still context dependent. This suggests that rather than being abstract and static, retrieval from semantic memory interacts dynamically with the context.     

Dissociating word stem completion and cued recall as a function of divided attention at retrieval

The aim of this study was to investigate the widely held, but largely untested, view that implicit memory (repetition priming) reflects an automatic form of retrieval. Specifically, in Experiment 1 we explored whether a secondary task (syllable monitoring), performed during retrieval, would disrupt performance on explicit (cued recall) and implicit (stem completion) memory tasks equally. Surprisingly, despite substantial memory and secondary costs to cued recall when performed with a syllable-monitoring task, the same manipulation had no effect on stem completion priming or on secondary task performance. In Experiment 2 we demonstrated that even when using a particularly demanding version of the stem completion task that incurred secondary task costs, the corresponding disruption to implicit memory performance was minimal. Collectively, the results are consistent with the view that implicit memory retrieval requires little or no processing capacity and is not seemingly susceptible to the effects of dividing attention at retrieval.     

Synchrony effects in automatic and controlled retrieval

Using a speeded retrieval procedure, we investigated time-of-day effects in automatic and controlled retrieval. Morning-type adults were tested at either peak (early morning) or off-peak (late afternoon) times on a speeded implicit (Experiment 1) or explicit (Experiment 2) stem completion task. In Experiment 1, retrieval strategies were identified by changes in response speed between a practice phase with rapid retrieval and an implicit memory test phase. Performance based on controlled retrieval (shown by slowdown participants) showed more priming at peak than at off-peak times of day, a finding confirmed in Experiment 2, in which the participants were given intentional retrieval instructions when the materials switched. In contrast, performance based on automatic retrieval (shown by nonslowdown participants) did not differ across peak and off-peak times. The finding suggests a robust synchrony effect in controlled retrieval, but not in automatic retrieval, which does not appear to vary across the day.     

Level of processing and the process-dissociation procedure: elusiveness of null effects on estimates of automatic retrieval

We describe two experiments that used the process-dissociation procedure to investigate the effects of level of processing on estimates of controlled and automatic retrieval processes in word-stem completion tasks. Despite our best endeavours, we found the null effect of level of processing on estimates of automatic retrieval reported by Toth, Reingold, and Jacoby (1994) elusive. Estimates of automatic retrieval were not independent of level of processing but inversely related to it. In part, the reason was that, following deeper levels of processing, instructions to exclude recollected words led to floor effects. But the inverse relationship persisted even when floor effects were avoided. Only participants who were not given strict instructions in the exclusion task-and who also qualified as lax responders based on answers in a structured post-test interview-showed no effect of level of processing on estimates of automatic retrieval. This null effect apparently occurred because these participants failed to exclude words that they in fact recollected from the study list. This finding violates the critical assumption that in this task participants exclude recollected words. The results are therefore paradoxical. Successful replication of the null effect occurred only under conditions that preclude the very use of the procedure. This paradox has important implications for views on how consciousness should be conceived in relation to memory.     

The role of working memory capacity in multiple-cue probability learning

Multiple-cue probability learning (MCPL) involves learning to predict a criterion when outcome feedback is provided for multiple cues. A great deal of research suggests that working memory capacity (WMC) is involved in a wide range of tasks that draw on higher level cognitive processes. In three experiments, we examined the role of WMC in MCPL by introducing measures of working memory capacity, as well as other task manipulations. While individual differences in WMC positively predicted performance in some kinds of multiple-cue tasks, performance on other tasks was entirely unrelated to these differences. Performance on tasks that contained negative cues was correlated with working memory capacity, as well as measures of explicit knowledge obtained in the learning process. When the relevant cues predicted positively, however, WMC became irrelevant. The results are discussed in terms of controlled and automatic processes in learning and judgement.     

The development of automatic and controlled inhibitory retrieval processes in true and false recall

In three experiments, we investigated the role of automatic and controlled inhibitory retrieval processes in true and false memory development in children and adults. Experiment 1 incorporated a directed forgetting task to examine controlled retrieval inhibition. Experiments 2 and 3 used a part-set cue and retrieval practice task to examine automatic retrieval inhibition. In the first experiment, the forget cue had no effect on false recall for adults but reduced false recall for children. In Experiments 2 and 3, both tasks caused retrieval impairments for true and false recall, and this occurred for all age groups. Implicit inhibition, which occurs outside of our conscious control, appears early in childhood. However, because young children do not process false memories as automatically as adults, explicit inhibition can reduce false memory output.     

Intention superiority effect on implicit memory of shopping lists: Activation and inhibition processes

Intentional memory is defined as the ability to remember to perform intentions in the future. Forming an intention such as “shopping” activates access to memories related to the products on the shopping list. As Intention Superiority Effect (ISE) studies show, these memories are more accessible in semantic and episodic memory, more activated over time and protected from competing representations. The inhibition of competing representations in intentional memory has been little examined so far. In this study we attempt to analyze changes in activation in the recall of products on a shopping list and competitors through implicit memory tasks. Sixty-five participants learned two shopping lists on a computer. Later, they were told to virtually buy one of them (prospective list) and not the other (neutral list). Prior to intentional task execution, they performed an implicit retrieval task in which we manipulated the appearance or not of cues from the intentional list and analyzed the influence of the items from the intentional list on items related to intentional and neutral lists. The main result of this study is that intention retrieval by intentional cues strengthens the activation of products related to the intentional list and/or inhibits competing products related to the neutral list. The inhibition is episodic rather than semantic in nature. The ISE requires the recall of the intention during the retention period through intentional cues for maintaining the intention. This seems to defend automatic recovery theories and not the intention persistence hypothesis. Also, the results are better explained by the directed forgetting paradigm rather than by the retrieval-induced forgetting paradigm.     

What matters in implicit task sequence learning: perceptual stimulus features, task sets, or correlated streams of information?

Implicit task sequence learning may be attributed to learning the order of perceptual stimulus features associated with the task sequence, learning a series of automatic task set activations, or learning an integrated sequence that derives from 2 correlated streams of information. In the present study, our purpose was to distinguish among these 3 possibilities. In 4 separate experiments, we replicated and extended a previous study by Heuer, Schmidtke, and Kleinsorge (2001). The presence or absence of a sequence of tasks, as well as that of a sequence of different task-to-response mappings, was manipulated independently within experiments. Evidence of implicit sequence learning was found only when correlated sequences of tasks and mappings were present. No sequence learning effects were found when only a single task sequence or a single mapping sequence was present, even when the structure of the single sequence was identical to the structure of the integrated sequence of task-mapping combinations. These results suggest that implicit task sequence learning is not dependent on either perceptual learning of stimulus features or automatic task-set activation per se. Rather, it appears to be driven by correlated streams of information.     

Phonological similarity effects in simple and complex span tasks

Three experiments were conducted to examine the effect of phonological similarity in simple and complex memory span tasks. In Experiment 1, participants performed either a simple or a complex span task, and the memoranda within lists were either phonologically similar or distinct. Phonologically similar lists consisted of words that rhymed.The simple span task was word span. There were two complex span tasks; one was the original reading span task, and the other was a variant of reading span in which all the sentences within a list were contextually related. The classic phonological similarity decrement was observed in word span. In contrast, phonological similarity facilitation was observed in both versions of reading span. This facilitation effect was further investigated in Experiment 2 using two new versions of reading span. In Experiment 2, the sentences in reading span were either short or long, and the memoranda were presented separately from, and were unrelated to, the sentences. Again, words within phonologically similar lists rhymed, and again, facilitation was observed. In Experiment 3, phonological similarity was operationalized in terms of feature overlap, rather than rhyme. The classic phonological similarity decrement was still observed in word span, but facilitation was not observed in complex span. The results suggest that phonological similarity, when operationalized using words that rhyme, serves as a list retrieval cue and that complex span tasks are more dependent on cue-driven memory retrieval mechanisms than are simple span tasks.     

Dissociating word stem completion and cued recall as a function of divided attention at retrieval

The aim of this study was to investigate the widely held, but largely untested, view that implicit memory (repetition priming) reflects an automatic form of retrieval. Specifically, in Experiment 1 we explored whether a secondary task (syllable monitoring), performed during retrieval, would disrupt performance on explicit (cued recall) and implicit (stem completion) memory tasks equally. Surprisingly, despite substantial memory and secondary costs to cued recall when performed with a syllable-monitoring task, the same manipulation had no effect on stem completion priming or on secondary task performance. In Experiment 2 we demonstrated that even when using a particularly demanding version of the stem completion task that incurred secondary task costs, the corresponding disruption to implicit memory performance was minimal. Collectively, the results are consistent with the view that implicit memory retrieval requires little or no processing capacity and is not seemingly susceptible to the effects of dividing attention at retrieval.     

The time course of object-feature retrieval in recognition

The time course of perception and retrieval of object features was investigated. Participants completed a perceptual matching task and 2 recognition tasks under time pressure. The recognition tasks imposed different retention loads. A stochastic model of feature sampling with a Bayesian decision component was used to estimate the rate of feature perception and the rate of retrieval of feature information. The results demonstrated that retrieval rates did not differ among object features if only a single object was held in memory. If 2 objects were retained in memory, differences among retrieval rates of features emerged, indicating that features that were quickly perceived were also quickly retrieved. The results from the 2-object retention condition are compatible with process reinstatement models of retrieval.     

Controlled and automatic uses of memory in depressed patients: effect of retention interval lengths

The present study examines controlled and automatic uses of memory in clinically depressed patients by applying the Process Dissociation Procedure developed by Jacoby (1991) to a stem completion memory task with short and long retention intervals. The results show that the contribution of controlled processes is lower in depressed patients than in controls, especially for the longest retention interval, whereas the contribution of automatic processes is equivalent in both groups and unaffected by the length of the retention interval. These findings are discussed in a cognitive control framework.