Process dissociation procedure reveals age differences in unconscious influences on memory for possible and impossible objects

Abstract

Forty-eight younger and 48 older adults performed inclusion and exclusion tasks for line drawings of possible and impossible objects that were encoded semantically or globally. Participants' performance was transformed into estimates of conscious and unconscious influences on memory via the Process Dissociation Procedure (PDP). Five major findings were obtained. First, developmental differences were observed in the relative strength of conscious and unconscious influences on memory such that conscious influences were stronger for younger than older adults, whereas unconscious influences were stronger for older than younger adults. Second, unconscious influences on memory were demonstrated for possible and impossible objects. Third, unconscious influences on memory were obtained for objects that were encoded in both a global and a semantic fashion. Fourth, age-related differences in conscious and unconscious influences on memory were unaffected by object type. Fifth, estimates of conscious and unconscious influences on memory were unrelated to scores on psychometric measures of visual-spatial ability: Primary Mental Ability-Space (PMA-Space) and Benton Facial Recognition Task (BFRT). Collectively, these findings have implications for our understanding of the relative strength of conscious and unconscious memory processes in younger and older adults as well as the different types of unconscious memory processes that are recruited by the PDP in comparison to the traditional priming methodology.     

内隐记忆的证明逻辑与加工分离说（PDP）的修正模型

讨论了内隐记忆的证明逻辑和内隐与外显测验中的意识和无意识影响问题。间接证明内隐记忆的逻辑应用在功能分离实验中。它的前提假设是记忆测验都是＂纯净＂的。直接证明逻辑应用在匹配比较实验中。它认为测验中的意识和无意识影响是并存的,Ｊａｃｏｂｙ等人近期提出的加工分离说（ＰＤＰ）在匹配比较法的基础上,将测验中的意识和无意识影响进行了分离,并借用经典测验理论的公式计算这两种影响。作者认为,按照概率论关于两个随机独立事件之和与积的运算法则,必须把包含测验（ｉｎｃｌｕｓｉｏｎｔｅｓｔ）的公式修正为Ｉｎｃｌｕｓｉｏｎ＝Ｒ（１－ａ）＋Ａ（１－Ｒ）。修正过的ＰＤＰ由四个方程组成。它不仅考虑了原ＰＤＰ忽视的外显条件下的无意识缺失（１－ａ）,而且可以更加确切地估计回忆概率（Ｒ）。这在数学理论上已找到了证据。     

Conscious and unconscious influences of memory: temporal dynamics

Changes in the conscious and unconscious influences of memory over time were assessed in two experiments by using a variant of the process-dissociation procedure. In both experiments, performance on a stem-completion task was measured under both inclusion and exclusion instructions. Across the two experiments, there were four different retention intervals: 2 minutes, 2 days, 2 weeks, and 2 months. The results indicated that conscious influences decreased systematically across retention interval. In contrast, unconscious influences of memory in the absence of conscious influences increased between 2 minutes and 2 days, and then remained relatively stable from 2 days to 2 weeks to 2 months. These results stand in apparent contrast to those of McBride and Dosher (1999), which showed equal rates of forgetting for conscious and unconscious influences of memory on performance. The implications for models of the relation between conscious and unconscious influences of memory on performance are discussed.     

Conscious and unconscious processes: the effects of motivation

The process-dissociation procedure has been used in a variety of experimental contexts to assess the contributions of conscious and unconscious processes to task performance. To evaluate whether motivation affects estimates of conscious and unconscious processes, participants were given incentives to follow inclusion and exclusion instructions in a perception task and a memory task. Relative to a control condition in which no performance incentives were given, the results for the perception task indicated that incentives increased the participants' ability to exclude previously presented information, which in turn both increased the estimate of conscious processes and decreased the estimate of unconscious processes. However, the results also indicated that incentives did not influence estimates of conscious or unconscious processes in the memory task. The findings suggest that the process-dissociation procedure is relatively immune to influences of motivation when used with a memory task, but that caution should be exercised when the process-dissociation is used with a perception task.     

Antimnemonic effects of schemas in young and older adults

Schema-consistent material that is aligned with an individual’s knowledge and experience is typically more memorable than abstract material. This effect is often more extreme in older adults and schema use can alleviate age deficits in memory. In three experiments, young and older adults completed memory tasks where the availability of schematic information was manipulated. Specifying nonobvious relations between to-be-remembered word pairs paradoxically hindered memory (Experiment 1). Highlighting relations within mixed lists of related and unrelated word pairs had no effect on memory for those pairs (Experiment 2). This occurred even though related word pairs were recalled better than unrelated word pairs, particularly for older adults. Revealing a schematic context in a memory task with abstract image segments also hindered memory performance, particularly for older adults (Experiment 3). The data show that processing schematic information can come with costs that offset mnemonic benefits associated with schema-consistent stimuli.     

Is prospective memory enhanced by cue-action semantic relatedness and enactment at encoding?

Benefits and costs on prospective memory performance, of enactment at encoding and a semantic association between a cue-action word pair, were investigated in two experiments. Findings revealed superior performance for both younger and older adults following enactment, in contrast to verbal encoding, and when cue-action semantic relatedness was high. Although younger adults outperformed older adults, age did not moderate benefits of cue-action relatedness or enactment. Findings from a second experiment revealed that the inclusion of an instruction to perform a prospective memory task led to increments in response latency to items from the ongoing activity in which that task was embedded, relative to latencies when the ongoing task only was performed. However, this task interference 'cost' did not differ as a function of either cue-action relatedness or enactment. We argue that the high number of cue-action pairs employed here influenced meta-cognitive consciousness, hence determining attention allocation, in all experimental conditions.     

Mechanisms of autobiographical memory retrieval in younger and older adults

In this study, retrieval of autobiographical memories was compared within or without the context of a lifetime period and between younger and older adults. The results of two experiments demonstrated that memories were more accessible for younger and older adults when they were retrieved within a time period context than without such context. However, when the retrieval context was more constrained and limited to cue word memories, the benefit of retrieval context disappeared. The results also suggested that as compared with younger adults, older adults were more likely to selectively retain memories with distinctive characteristics, such as being self-relevant and emotionally intense, particularly when remote memories were involved. Mechanisms of autobiographical memory retrieval in younger and older adults.     

Effects of repetition on associative recognition in young and older adults: item and associative strengthening

Young and older adults studied word pairs and later discriminated studied pairs from various types of foils including recombined word-pairs and foil pairs containing one or two previously unstudied words. We manipulated how many times a specific word pair was repeated (1 or 5) and how many different words were associated with a given word (1 or 5) to tease apart the effects of item familiarity from recollection of the association. Rather than making simple old/new judgments, subjects chose one of five responses: (a) Old-Old (original), (b) Old-Old (rearranged), (c) Old-New, (d) New-Old, (e) New-New. Veridical recollection was impaired in old age in all memory conditions. There was evidence for a higher rate of false recollection of rearranged pairs following exact repetition of study pairs in older but not younger adults. In contrast, older adults were not more susceptible to interference than young adults when one or both words of the pair had multiple competing associates. Older adults were just as able as young adults to use item familiarity to recognize which word of a foil was old. This pattern suggests that recollection problems in advanced age are because of a deficit in older adults' formation or retrieval of new associations in memory. A modeling simulation provided good fits to these data and offers a mechanistic explanation based on an age-related reduction of working memory.     

Conscious and unconscious influences on remembering information from the near and distant past: A developmental analysis

We examined adults' memory for the actors and actresses who won Academy Awards for their performances in specific motion pictures between 1992 to 1937. Fifty-six individuals between 41 to 81 years of age completed inclusion and exclusion versions of aMovie Memory Questionnaire in which they were required to identify actors and actresses who were paired with the names of movies they actually appeared in (e.g., Cher—Moonstruck) or they never appeared in (e.g., Robert DeNiro—Annie Hall), respectively. Estimates of the independent contributions of conscious and unconscious influences on recollection were obtained by analyzing subjects' performance on the inclusion and exclusion tasks via Jacoby's (1991)Process Dissociation Procedure. Results indicated that conscious recollection for motion picture information exhibited a typical retention function, whereas unconscious contributions to recollection remained relatively constant over the entire time range that was sampled. When age differences were considered, it was found that young-old participants displayed a higher level of conscious recollection than did middle-age and old-old adults. The role played by unconscious processes in recollection, however, did not vary by age group.     

Analyzing estimates of automatic and conscious retrieval in between- and within-subjects designs

The process dissociation procedure (PDP) was developed as a means of quantifying the contributions of conscious and automatic retrieval to memory performance. Although the required inclusion and exclusion conditions are manipulated within subjects in most experiments, several researchers have expressed concerns that the instructions may be particularly difficult to follow under these conditions. Thus, manipulating instructions between subjects may have some advantages, although some aspects of the statistical analysis of conscious and automatic estimates are not routine in such a design. We describe a procedure for this analysis and present some initial data to illustrate its application to PDP. We also comment on other issues related to the calculation of estimates of automatic and conscious retrieval in between- and within-subjects designs.     

有多少记忆可以内隐——兼评Jacoby加工分离程序

自从1991Jacoby使用简单的再认任务分离出意识性提取与无意识熟悉性以来,虽然PDP的计算范式也受到一些修正,但均没有在计算范式的内核思想上改进过,只是PDP延伸出的应用研究非常多。其实,Jacoby在构建PDP范式时,从描述PDP的心理现象、构建数学模型到PDP在实践中的应用上均出现了重大失误。本研究从上述三个方面对PDP提出了质疑,使用集合模型重新构建了PDP计算模型,用实验验证了PDP新模型,纠正了Jacoby理论与应用的三大错误。     

Effects of age and divided attention on memory components derived for the category exemplar generation task

Age differences in memory performances on a conceptually driven task, the category exemplar generation (CEG) test, were investigated. Thirty-six younger adults and 36 healthy older adults studied word lists in full and divided attention conditions. Recall was tested with category names. The process-dissociation procedure was used to derive estimates of controlled and automatic memory. Old-old adults (70-84 years) exhibited poorer conscious recollection than both younger (18-24) and young-old adults (59-69). In contrast, no age differences were found in estimates of automatic memory. For the younger and older adults, the divided encoding manipulation reduced both the consciously controlled and automatic estimates of memory. The results suggest that the few prior findings of age deficits in priming on the CEG may have been an artifact of contamination from conscious retrieval processes. They also indicate that the opportunity for greater semantic processing enhances the conceptual priming of both younger and older adults.     

Aging and the Deletion Function of Inhibition

The present study was adapted from the sentence completion task of Hartman and Hasher (1991). We addressed the question raised by Burke (1997): are the age-related differences in priming effects found in that task better explained by deficits in explicit memory or by inefficient inhibitory mechanisms? In the study phase, older and younger adults read high cloze sentences ending with an expected or an unexpected final word. In the second phase, participants were asked to complete sentence frames with either the final word presented during the study phase (inclusion condition) or with another, new word (exclusion condition). The third phase was an indirect memory test of perceptual identification. Finally, we compared explicit memory for recalled and inhibited words in a recognition test. In perceptual identification by older adults, priming was equivalent for recalled and inhibited words, whereas in younger adults priming was higher for recalled than for inhibited words. In the explicit memory test, recognition scores were lower for inhibited words in both age groups. These results are consistent with the view of Hasher and Zacks (1988), who assume an age-related decline in the ability to suppress no-longer-relevant information     

再认记忆中的概率学习效应:加工分离框架

采用加工分离程序(PDP)与多项加工树模型,对比检验PDP与背景鉴别模型的构思效度;操纵加工水平与项目比例,考察再认记忆中的内隐学习效应。结果表明:(1)包含和排除测验都表现出加工水平效应,包含测验具有视听通道效应。(2)在单一操作中分离出意识回忆和自动加工两种过程。(3)在语义编码条件下出现了概率学习效应,自动加工可能具有情境依存性。未发现支持背景鉴别模型的结果。     

Conscious and unconscious influences of memory for object location

The process-dissociation procedure was used to investigate conscious and unconscious influences of memory for object location. In two experiments, subjects worked with drawings of household objects and rooms of a house depicted on a computer monitor to simulate placing objects in various locations. Memory for object locations was tested by having subjects search for those objects. A double dissociation was obtained between estimates of conscious and unconscious influences of memory computed from equations that assumed independence between these two influences: Age-related differences were found in the estimate of conscious influences, but not in the estimate of unconscious influences, whereas manipulation of habit strength affected the unconscious estimate, but not the conscious estimate. These results were closely fit by a multinomial model assuming independence between conscious and unconscious influences of memory.     

FOK与情节记忆、语义记忆和内隐记忆关系的研究

实验采用R/K判断和PDP测量技术,研究了FOK判断与情节记忆、语义记忆和内隐记忆关系及其监测强度.实验结果表明FOK判断的准确性程度为R判断＞K判断,即对情节记忆监测的准确性要大于对语义记忆监测的准确性.FOK对于自动加工的预测准确性差异不显著,说明FOK监测对内隐记忆的作用是微弱的,由此推测无记忆是意识最高层面的活动.对记忆监测水平强度是由意识--无意识逐渐减弱的.FOK判断对意识性水平较高的记忆活动监测的准确性较强.     

Executive function across the life span

The development and determinants of executive function (EF) were studied in children (mean age=8.8 years), young adults ( M= 22.3 years), and elderly adults (M = 7 years). EF was indexed by perseverative responding on two bidimensional sorting tasks (Visually Cued Color-Shape task and Auditorily Cued Number-Numeral task), and age-related changes in EF were considered in relation to estimates of conscious vs. unconscious memory that were obtained using the process dissociation procedure (PDP). Results revealed the rise and fall of EF across the life span, with significant quadratic trends found for performance on both sorting tasks and for the conscious recollection component (C) of the PDP task. Regression analyses indicated that PDP estimates of conscious memory accounted for variation in performance on the visual sorting task, but not on the auditory sorting task. The findings are discussed in terms of their implications for hierarchical models of EF and its development.     

Effects of Age and Divided Attention on Memory Components Derived for the Category Exemplar Generation Task

ABSTRACT

Age differences in memory performances on a conceptually driven task, the category exemplar generation (CEG) test, were investigated. Thirty-six younger adults and 36 healthy older adults studied word lists in full and divided attention conditions. Recall was tested with category names. The process-dissociation procedure was used to derive estimates of controlled and automatic memory. Old-old adults (70–84 years) exhibited poorer conscious recollection than both younger (18–24) and young-old adults (59–69). In contrast, no age differences were found in estimates of automatic memory. For the younger and older adults, the divided encoding manipulation reduced both the consciously controlled and automatic estimates of memory. The results suggest that the few prior findings of age deficits in priming on the CEG may have been an artifact of contamination from conscious retrieval processes. They also indicate that the opportunity for greater semantic processing enhances the conceptual priming of both younger and older adults.     

Paying attention to binding: Further studies assessing the role of reduced attentional resources in the associative deficit of older adults

The present experiments investigated whether the observed associative deficit in older adults' episodic memory is mediated by a reduction of attentional resources. Using a dual-task procedure, younger and older participants studied lists of word pairs either under full attention or while performing a concurrent task. Both experiments showed that dividing attention did not cause a greater impairment to memory for associations than to memory for items in either age group. Furthermore, an analysis of concurrent task performance revealed that older adults' attentional costs for both learning and binding items were not larger than for learning items alone, relative to younger adults. These data provide support for a multicausal interpretation of older adults' memory deficits in which common, depleted attentional resources may be a mechanism that reduces memory for components of an episode in both older and younger adults under divided attention at encoding. In addition, older adults have a unique deficit in memory for the associations between the components, which does not seem to be resource dependent.     

Age-related differences in recognition memory: effects of materials and context change

The study explored age-related differences in the effects of context change on recognition memory by presenting object names (Expt. 1A) or their pictures (Expt. 1B) on background scenes. Participants later attempted to recognize previously presented items on background scenes that were original, switched, blank, or new. Older adults recognized fewer word stimuli than did younger adults, and context effects were larger for older adults. With pictures, however, the age-related decrement was eliminated and context effects were reduced. The beneficial effect of context reinstatement in older adults occurs despite the finding that they are less able to recall or recognize such contexts (Experiment 2). Older adults can use context information in recognition memory at least as efficiently as younger adults when suitable materials and conditions are provided.