Event-related potentials and recognition memory

According to dual-process models, recognition memory is supported by distinct retrieval processes known as familiarity and recollection. Important evidence supporting the dual-process framework has come from studies using event-related brain potentials (ERPs). These studies have identified two topographically distinct ERP correlates of recognition memory--the "parietal" and "mid-frontal" old/new effects--that are dissociated by variables that selectively modulate recollection and familiarity, respectively. We evaluate the extent to which ERP data support dual-process models in light of the proposal that recollection is a continuous rather than a discrete memory process. We also examine the claim that the putative ERP index of familiarity is a reflection of implicit rather than explicit memory. We conclude that ERP findings continue to offer strong support for the dual-process perspective.     

Recognition memory and prefrontal cortex: dissociating recollection and familiarity processes using rTMS

Recognition memory can be supported by both the assessment of the familiarity of an item and by the recollection of the context in which an item was encountered. The neural substrates of these memory processes are controversial. To address these issues we applied repetitive transcranial magnetic stimulation (rTMS) over the right and left dorsolateral prefrontal cortex (DLPFC) of healthy subjects performing a remember/know task. rTMS disrupted familiarity judgments when applied before encoding of stimuli over both right and left DLPFC. rTMS disrupted recollection when applied before encoding of stimuli over the right DLPFC. These findings suggest that the DLPFC plays a critical role in recognition memory based on familiarity as well as recollection.     

FN400和LPC对熟悉性和回想的特异性指向分析

双加工理论认为熟悉性和回想是情景记忆的两个独立过程,其重要证据是ERP研究中FN400和LPC可以分别指示熟悉性和回想。但也有研究证明FN400是概念启动和熟悉性共同作用的结果,而LPC也不能准确的反映回想加工,因此,将其作为双加工理论证据的可靠性需进一步讨论。未来需进一步明确概念启动和熟悉性影响FN400的前提条件,并在提高生态效度和控制额外变量的同时明晰LPC的指向性,同时探究熟悉性和回想在再认过程中的具体作用方式。     

从整合的角度看联结记忆中的项目再认

联结记忆由三种成分构成：项目1, 项目2以及项目1-项目2之间的联结, 其中, 对项目1和项目2的再认称之为项目再认, 而对项目1-项目2之间联结的再认称之为联结再认。双加工理论认为项目再认可以由熟悉性和回想加工来完成, 而联结再认只能由回想加工来完成。但近期有大量的研究发现：当要学习的项目对被整合为一个新的整体表征时, 熟悉性也能够支持联结再认。而关于整合对联结记忆中项目再认的研究较少, 总结已有研究提出两种观点：一种是“只有受益”观点(benefits-only)认为整合在增加联结再认的同时不影响项目再认; 另一种是“收支平衡”观点(costs and benefits)认为整合增加联结再认是以牺牲项目再认为代价的。未来研究应该关注整合对联结记忆中项目再认的影响及其神经机制, 了解整合对联结再认和项目再认的具体作用, 有助于针对具体记忆任务选择合适的编码方式来提高记忆表现。     

The contribution of familiarity to within- and between-domain associative recognition memory: Use of a modified remember/know procedure

The purpose of the present study was to determine the extent to which familiarity can support associative recognition memory as a function of whether the associations are within- or between-domain. Standard recognition and familiarity only performance were compared in different participants, using a new adaptation of the remember/know procedure. The results indicated that within-domain (face–face) associative recognition was mainly supported by familiarity. In contrast, familiarity provided relatively poor support to between-domain (face–name) associative recognition for which optimal performance required a major recollection contribution. These findings suggest that familiarity can support associative recognition memory, particularly for within-domain associations, and contrast with the widely held view that associative recognition depends largely on recollection.     

Individual differences in forced-choice recognition memory: Partitioning contributions of recollection and familiarity

In forced-choice recognition memory, two different testing formats are possible under conditions of high target–foil similarity: Each target can be presented alongside foils similar to itself (forced-choice corresponding; FCC), or alongside foils similar to other targets (forced-choice noncorresponding; FCNC). Recent behavioural and neuropsychological studies suggest that FCC performance can be supported by familiarity whereas FCNC performance is supported primarily by recollection. In this paper, we corroborate this finding from an individual differences perspective. A group of older adults were given a test of FCC and FCNC recognition for object pictures, as well as standardized tests of recall, recognition, and IQ. Recall measures were found to predict FCNC, but not FCC performance, consistent with a critical role for recollection in FCNC only. After the common influence of recall was removed, standardized tests of recognition predicted FCC, but not FCNC performance. This is consistent with a contribution of only familiarity in FCC. Simulations show that a two-process model, where familiarity and recollection make separate contributions to recognition, is 10 times more likely to give these results than a single-process model. This evidence highlights the importance of recognition memory test design when examining the involvement of recollection and familiarity.     

Identifying the Basis for the Word Frequency Effect in Recognition Memory

Abstract

Recent theories of recognition memory have identified two bases on which recognition-memory judgments may be made: recollection, which involves retrieval of contextual information from an earlier episode of stimulus presentation; and familiarity, which is distinguished by a general sense of familiarity in the absence of recollection. Four experiments were conducted to test whether the word frequency effect (WFE) in recognition memory (superior performance with low- in comparison with high-frequency targets) results from recollection-based processes, familiarity-based processes, or both. In two of the experiments, superior memory for aspects of the study context was found for low-frequency in comparison with high-frequency words, suggesting frequency-related differences in recollection. The other two experiments used Jacoby's (1991) inclusion/exclusion paradigm to provide estimates of the contribution of recollection and familiarity to recognition. In both experiments the data suggested that the WFE is primarily a recollection-based phenomenon. These findings suggest that the recognition memory WFE for old items results primarily from the effects of word frequency on recollection. The implications of these findings for theories of recognition memory are discussed.     

不同情绪背景下来源记忆的ERPs研究*

使用事件相关电位(ERP)技术和测试来源记忆的多键范式,探讨不同情绪效价背景下来源提取的认知神经机制。学习阶段,同时呈现汉字和3种效价情绪图片(重叠);测验阶段,只呈现汉字,要求被试进行四键判断：旧字且背景为中性,旧字且背景为正性,旧字且背景为负性,新字。结果发现：在提取阶段,刺激呈现后300~500 ms,3种情绪背景下来源判断正确项目和来源判断错误项目都比新项目诱发了更正的ERPs(即都存在新旧效应),这一结果反映出刺激呈现后300~500 ms 是一个早期的项目提取阶段,它独立于来源提取。并且,在中性背景下,两种新旧效应没有差别;而在正性和负性背景下,来源判断正确项目的新旧效应显著大于来源判断错误项目。说明相比于中性背景,情绪背景下被试可能更早对来源信息产生熟悉感。在500~650 ms,3种情绪背景下都存在来源判断正确项目的新旧效应,在来源判断错误项目和新项目之间没有显著差异,来源正确与来源错误有显著的新旧效应差异,但二者在头皮分布上是类似的,这反映了晚期的来源提取过程。同时来源正确的新旧效应在这两个时段有显著不同的头皮分布,表明这两个时段有不同加工过程。另外,在500~650 ms,存在显著的情绪效应,正性背景下正确判断来源诱发的ERPs比中性和负性背景下的更正,而且来源判断错误条件下没有情绪效应。综上所述,来源正确和来源错误可能仅仅反映了大脑激活在量上的不同,并不能推断两者存在质的差异;大脑神经活动的早期不仅反映了对记忆项目的熟悉性,而且也受情绪效应的影响,500 ms之后大脑神经活动反映的是对记忆项目回想的过程,这一回想过程也与情绪效应有关,受到情绪效应的调节。     

Measuring recollection and familiarity: Improving the remember/know procedure

The remember/know (RK) procedure is the most widely used method to investigate recollection and familiarity. It uses trial-by-trial reports to determine how much recollection and familiarity contribute to different kinds of recognition. Few other methods provide information about individual memory judgements and no alternative allows such direct indications of recollection and familiarity influences. Here we review how the RK procedure has been and should be used to help resolve theoretical disagreements about the processing and neural bases of components of recognition memory. Emphasis is placed on procedural weaknesses and a possible confound of recollection and familiarity with recognition memory strength. Recommendations are made about how to minimise these problems including using modified versions of the procedure. The proposals here are important for improving behavioural and lesion research, and vital for brain imaging work.     

ROC in animals: Uncovering the neural substrates of recollection and familiarity in episodic recognition memory

It is a consensus that familiarity and recollection contribute to episodic recognition memory. However, it remains controversial whether familiarity and recollection are qualitatively distinct processes supported by different brain regions, or whether they reflect different strengths of the same process and share the same support. In this review, I discuss how adapting standard human recognition memory paradigms to rats, performing circumscribed brain lesions and using receiver operating characteristic (ROC) methods contributed to solve this controversy. First, I describe the validation of the animal ROC paradigms and report evidence that familiarity and recollection are distinct processes in intact rats. Second, I report results from rats with hippocampal dysfunction which confirm this finding and lead to the conclusion that the hippocampus supports recollection but not familiarity. Finally, I describe a recent study focusing on the medial entorhinal cortex (MEC) that investigates the contribution of areas upstream of the hippocampus to recollection and familiarity.     

一体化促进联结记忆的作用机制：熟悉性和回想加工

当两个或两个以上项目进行一体化编码时, 熟悉性也能够支持联结再认, 这一观点已经得到大量研究证据的支持。然而, 关于一体化如何影响联结再认和构成联结的单个项目再认仍存在分歧。通过回顾现有研究发现：(1)一体化一致性是调节一体化与联结再认关系的重要因素; (2)认知资源有限和新/旧词语义相关性是影响一体化对项目再认作用的重要因素; (3)一体化的发生机制存在“项目假说”、“图式假说”以及“精细加工假说”三种可能的理论解释。未来研究不仅需要控制一体化一致性, 还可以比较不同一体化方式的作用大小以及探索一体化效应的毕生发展规律。     

流畅性对再认的影响:实验证据及理论解释

流畅性可以影响再认,而且仅影响熟悉性加工的观点已得到大量研究的证实。近年一些研究者采用掩蔽启动范式并结合修改的R/K范式、独立判断的R/K范式等实验范式,操控测验项目的流畅性,发现流畅性影响的可能是猜测或者回想加工,因而质疑这个结论。为解释流畅性对再认的影响,流畅性归因理论侧重对流畅性的归因、冲突-归因理论侧重期待流畅性和实际流畅性之间的冲突、预激活-适应模型侧重启动刺激引起的神经活动激活或适应、线索-学习理论侧重流畅性线索的有效性。未来研究应关注流畅性对来源和联结记忆的影响,并考察流畅性对再认的影响在不同年龄人群或遗忘症人群中的表现是否一致。     

Neuropsychological correlates of recollection and familiarity in normal aging

The dual-process model of recognition memory proposed by Jacoby (1991; see also Mandler, 1980) postulates the existence of two independent components of recognition memory: a conscious retrieval process (recollection) and an automatic component ( familiarity). Older adults appear to be impaired in recollection, but findings with respect to familiarity have been mixed. Studies of the brain bases of these components, using neurological patients, have also been inconclusive. We examined recollection and familiarity, using the process dissociation procedure, in older adults characterized on the basis of both their frontal and their medial temporal lobe function. Findings suggest that only some older adults, depending on their neuropsychological status, are impaired in recollection and/or familiarity: Recollection seems to involve both frontal and medial temporal lobe function, whereas familiarity appears to be dependent only on function associated with the medial temporal lobes.     

语义相似性下回忆和熟悉性的分离

该研究利用事件相关电位技术（ERPs）,采用以汉字为实验材料的学习-再认范式,考察了语义相似性下回忆和熟悉性的分离。本实验结果表明：熟悉性效应主要体现在330-430ms的额区,而回忆效应主要体现在430-600ms的中央区和顶区。本实验在以汉字为实验材料的情况下证明了,早期额区的N400新旧效应反映了熟悉性,晚期顶区LPC新旧效应反映了回忆,从汉语材料的角度,为双加工过程假说提供了新的证据。     

Moving beyond pure signal-detection models: comment on Wixted (2007)

The dual-process signal-detection (DPSD) model assumes that recognition memory is based on recollection of qualitative information or on a signal-detection-based familiarity process. The model has proven useful for understanding results from a wide range of memory research, including behavioral, neuropsychological, electrophysiological, and neuroimaging studies. However, a number of concerns have been raised about the model over the years, and it has been suggested that an unequal-variance signal-detection (UVSD) model that incorporates separate recollection and familiarity processes (J. T. Wixted, 2007) may provide an equally good, or even better, account of the data. In this article, the authors show that the results of studies that differentiate these models support the predictions of the DPSD model and indicate that recognition does not reflect the summing of 2 signal-detection processes, as the new UVSD model assumes. In addition, the assumptions of the DPSD model are clarified in order to address some of the common misconceptions about the model. Although important challenges remain, hybrid models such as this provide a more useful framework within which to understand human memory than do pure signal-detection models.     

Old processes,new perspectives: Familiarity is correlated with (not independent of) recollection and is more (not equally) variable for targets than for lures

According to dual-process models of memory, recognition is subserved by two processes: recollection and familiarity. Many variants of these models assume that recollection and familiarity make stochastically independent contributions to performance in recognition tasks and that the variance of the familiarity signal is equal for targets and for lures. Here, we challenge these ‘common-currency’ assumptions. Using a model-comparison approach, featuring the Continuous Dual Process (CDP; Wixted & Mickes, 2010) model as the protagonist, we show that when these assumptions are relaxed, the model’s fits to individual participants’ data improve. Furthermore, our analyses reveal that across items, recollection and familiarity show a positive correlation. Interestingly, this across-items correlation was dissociated from an across-participants correlation between the sensitivities of these processes. We also find that the familiarity signal is significantly more variable for targets than for lures. One striking theoretical implication of these findings is that familiarity—rather than recollection, as most models assume—may be the main contributor responsible for one of the most influential findings of recognition memory, that of subunit zROC slopes. Additionally, we show that erroneously adopting the common-currency assumptions, introduces severe biases to estimates of recollection and familiarity.     

Effects of retention intervals on receiver operating characteristics in artificial grammar learning

Current theories of memory suggest that recognition is composed of separate processes of familiarity and recollection (e.g. [Yonelinas, A. P. (2002). The nature of recollection and familiarity: a review of 30 years of research. Journal of Memory and Language, 46, 441-517]). A key feature of these two processes is that they decay, or are forgotten at different rates. The dual-process model has also been useful in understanding artificial grammar learning. We obtained evidence for recollection and familiarity in artificial grammar learning by analyses of receiver operating characteristics (ROC). Furthermore we found that these were dissociated by retention intervals of 14 days. The slope of the zROC curves deviated reliably from 1 immediately after study and increased towards 1 suggesting that recollection contributed to recognition decisions but declined over the 14-day period leaving familiarity as the only basis for recognition. These data show similar patterns to those observed in word-recognition [Gardiner, J. M., & Java, R. I. (1991). Forgetting in recognition memory with and without recollective experience. Memory &Cognition, 19, 617-623; Tunney, R. J. (submitted for publication). Changes in the subjective experience of recognition over time suggest independent processes] and confirm the view that recollection and familiarity are implicated in artificial grammar learning. Moreover, the data confirm the finding that recollection and familiarity-based memory show different patterns of forgetting.     

The medial temporal lobe and the attributes of memory

Neuroimaging and lesion studies have seemed to converge on the idea that the hippocampus selectively supports recollection. However, these studies usually involve a comparison between strong recollection-based memories and weak familiarity-based memories. Studies that avoid confounding memory strength with recollection and familiarity almost always find that the hippocampus supports both recollection and familiarity. We argue that the functional organization of the medial temporal lobe (MTL) is unlikely to be illuminated by the psychological distinction between recollection and familiarity and will be better informed by findings from neuroanatomy and neurophysiology. These findings indicate that the different structures of the MTL process different attributes of experience. By representing the widest array of attributes, the hippocampus supports recollection-based and familiarity-based memory of multiattribute stimuli.     

Dissociating familiarity from recollection using rote rehearsal

Recollection-based recognition memory judgments benefit greatly from effortful elaborative encoding, whereas familiarity-based judgments are much less sensitive to such manipulations. In this study, we have examined whether rote rehearsal under divided attention might produce the opposite dissociation, benefiting familiarity more than recollection. Subjects rehearsed word pairs during the "distractor" phase of a working memory span task, and were then given a surprise memory test for the distractor items at the end of the experiment. Experiment 1 demonstrated that increasing rehearsal elevated the recognition rate for intact and rearranged pairs, but neither associative recognition accuracy nor implicit fragment completion benefited from rehearsal. The results suggest that rote rehearsal leads to a greater increase in familiarity than in recollection, and that the increase in observed familiarity cannot be attributed to effects of repetition priming. In Experiment 2, we tested item recognition with the remember/know procedure, and the results supported the conclusions of Experiment 1. Moreover, a signal detection model of remember/know performance systematically overpredicted rehearsal increases in remember rates, and this worsened when high-rehearsal items were assumed to be more variable in strength. The results suggest that rote rehearsal can dissociate familiarity from recollection at the time of encoding and that item recognition cannot be fully accommodated within a one-dimensional signal detection model.     

Recognition memory for source and occurrence: The importance of recollection

Previous recognition memory studies indicate that when both recollection and familiarity are expected to contribute to recognition performance (e.g., discriminating studied items from nonstudied items) the dual-process and the unequal-variance signal detection models provide comparable accounts of performance. When familiarity is not expected to be useful (e.g., when items from two equally familiar sources are discriminated between), the dual-process model provides a significantly better account of performance. In the present study, source recognition was tested under conditions in which familiarity could have been used to perform a list-discrimination task; participants were required to discriminate between strong studied items, weak studied items, and new items. The dual-process model provided a better account of performance than did the unequal-variance model. Moreover, the results indicated that the unequal-variance assumption in a single-process signal detection model was not a valid substitution for recollection and that recollection was used to make recognition judgments even when assessments of familiarity were useful.