Memories of early childhood: Qualities of the experience of recollection

Memories judged to be recollections were contrasted with memories known to be based on second-hand sources in order to investigate the phenomenological qualities that underlie the experience of recollection. Adults rated the qualities of their recollections of an early childhood experience. Their ratings were compared with ratings of the qualities of memories of a similar autobiographical experience where the information was known to derive from other sources. Reported recollections were rated higher than memories based on other sources for many qualities, including sensory and spatial detail, location, thoughts, feelings, completeness, event detail, and pictorial representation. Comparison of the ratings of memories dating from different ages suggests that a memory may be judged to be recollected even if only a subset of the qualities characterizing recollections are present. This provides partial support for and clarification of Rubin's multiple-systems model of autobiographical memory.     

Medial temporal lobe memory in childhood: developmental transitions

The medial temporal lobes (MTL) support declarative memory and mature structurally and functionally during the postnatal years in humans. Although recent work has addressed the development of declarative memory in early childhood, less is known about continued development beyond this period of time. The purpose of this investigation was to explore MTL‐dependent memory across middle childhood. Children (6 –10 years old) and adults completed two computerized tasks, place learning (PL) and transitive inference (TI), that each examined relational memory, as well as the flexible use of relational learning. Findings suggest that the development of relational memory precedes the development of the ability to use relational knowledge flexibly in novel situations. Implications for the development of underlying brain areas and ideas for future neuroimaging investigations are discussed.     

The development of visual working memory capacity during early childhood

The change detection task has been used in dozens of studies with adults to measure visual working memory capacity. Two studies have recently tested children in this task, suggesting a gradual increase in capacity from 5 years to adulthood. These results contrast with findings from an infant looking paradigm suggesting that capacity reaches adult-like levels within the first year. The current study adapted the change detection task for use with children younger than 5 years to test whether the standard version of the task was too difficult and may have underestimated children's capacity. Results showed that 3- and 4-year-olds could successfully complete this modified task and that capacity increased roughly linearly, from 2 or 3 items during this period to 3 or 4 items between 5 and 7 years. Furthermore, performance did not differ significantly between the modified version and a replication of the standard version with 5- and 7-year-olds. Thus, there is no evidence that previous research with the change detection task underestimated children's capacity. Further research is needed to understand how performance relates across the infant looking task and change detection to provide a more complete picture of visual working memory capacity over development.     

Effects of association and repetition in memory for temporal order

Temporal order recognition memory has been examined previously with tasks involving a recency judgment between a pair of items in a preceding string. Recency judgments are impaired when the earlier item is repeated. The present study employed the comparative recency judgment paradigm, with the lists composed of words. The effect of the inclusion in the list of a high associate of the earlier test item was examined and compared to the effect of repetition. Associative interference was observed, but not in all conditions. Direction of association was a significant factor. The results were interpreted in terms of a model of word recognition proposed by Morton.     

Unitization mitigates interference by intrinsic negative emotion in familiarity and recollection of associative memory: Electrophysiological evidence

Emotion exerts varied influences on memory. While task-relevant item memory is often enhanced by emotion, associative memory is generally impaired. Unitization is known to improve associative memory, but its effects and mechanisms in protecting associative memory from emotional interference are rather obscure. The current study investigated associative memory by employing experimental manipulation of unitization (vs. nonunitization) encoding strategy and stimulus emotion (neutral, intrinsic negative, and extrinsic negative), combined with event-related potential (ERP) signatures of familiarity (FN400 old/new effects) and recollection (parietal late positive component/LPC old/new effects) in memory recognition. Both behavioral and ERP indices of associative recognition from the nonunitization group confirmed emotional interference in associative memory. Importantly, it was primarily intrinsic (vs. extrinsic) emotion that impeded associative memory. Unitization encoding improved memory performance in general, accompanied by enhanced recollection process and induction of familiarity process, which is typically not involved in associative memory recognition and was indeed absent in the nonunitization group. Importantly, unitization helped to preserve behavioral performance (specifically, response speed though not recognition strength) from interference by intrinsic emotion while largely reversed the detriment of intrinsic emotion on ERP indices of familiarity and recollection processes. Interestingly, a synergy between intrinsic emotion and unitization encoding was observed, which could underpin the facilitation of familiarity process in associative recognition of emotional pairs. Overall, current findings highlight interference by intrinsic emotion in associative memory, which is nonetheless responsive to mitigation by unitization encoding.     

The role of reminding in long-term memory for temporal order

Order codes are one of the three main types of information that have been hypothesized to underlie memory for the times of life events. Published evidence for the theory, however, has come exclusively from research in which brief retention intervals have been used. In the first of two studies, 101 adults judged the order of pairs of movies released 5-14 years ago, half of which shared a common major actor. There was no evidence that related films could be ordered more accurately than unrelated ones. In the second study, 88 students were presented with in-class announcements that were either related or unrelated to an earlier announcement. Three weeks later,they judged the order of the pairs of announcements. There was no difference between the accuracy for the related and the unrelated pairs. The findings do not support the proposal that the automatic creation of order information at the time of encoding contributes to autobiographical memory.     

Integrated memory for objects, places, and temporal order: evidence for episodic-like memory in mice

Human episodic memory refers to the recollection of an unique past experience in terms of what happened, and where and when it happened. Factoring out the issue of conscious recollection, episodic memory, even at the behavioral level, has been difficult to demonstrate in non-human mammals. Although, it was previously shown that rodents can associate what and when or what and where information given on unique trials, it proved to be difficult to demonstrate memory for what, where, and when simultaneously in mammals, without using extensive training procedures, which might induce semantic rather than episodic memory recall. Towards the goal of an animal model of human episodic memory we designed an three-trial object exploration task in which different versions of the novelty-preference paradigm were combined to subsume (a) object recognition memory, (b) the memory for locations in which objects were explored, and (c) the temporal order memory for object presented at distinct time points. We found that mice spent more time exploring two "old familiar" objects relative to two "recent familiar" objects, reflecting memory for what and when and concomitantly directed more exploration at a spatially displaced "old familiar" object relative to a stationary "old familiar" object, reflecting memory for what and where. These results suggest that during a single test trial the mice were able to (a) recognize previously explored objects, (b) remember the location in which particular objects were previously encountered, and (c) to discriminate the relative recency in which different objects were presented. According to the currently discussed behavioral criteria for episodic-like memory in animals, our results suggest that mice are capable to form such higher order memories.     

Strategic influences on recollection in the exclusion task: Electrophysiological evidence

One assumption underlying the use of the exclusion task as part of the process dissociation procedure is that studied items are successfully excluded only when they are recollected. The present study employed event-related potentials (ERPs) to demonstrate that successful exclusion does not necessarily require recollection. In two experiments, the study tasks for to-be-excluded items were identical, but the tasks employed withtarget items differed, giving better memory for these items in Experiment 1 than in Experiment 2. Successfully excluded items elicited the ERP signature for recollection—theleft parietal old/new effect—in Experiment 2 only. These findings indicate that the subjects adopted different retrieval strategies in the two experiments. It is suggested that they made more use of source information about to-be-excluded items in the second experiment than in the first.     

Pretend play and development in early childhood (with implications for the oedipal phase)

Pretend play reflects both the unique mental organization and the developmental challenges of early to middle childhood, with a trajectory that parallels the monumental transformation of the toddler to the school-age child. Despite evidence for various forms of playing throughout the life cycle, the flowering of symbolic play in this phase is specific, essential, and typically transient in terms of its dominance in the life of the child. It reflects the simultaneous emergence, processing, and integration of the remarkable developmental advances occurring during this period, most especially the capacity to symbolize, in the service of the exponentially expanded psychosexual/social/emotional force field implied in the contemporary use of the term oedipus complex. Moreover, it constitutes a particular mental organization and ego state, with idiosyncratic mentation, affect regulation, and relationship to inner and outer experience, that accompanies the child's gradual orientation to consensual reality. Subsequent access to some form of this state varies widely among individuals but is rarely fully comparable.     

Positional and temporal clustering in serial order memory

The well-known finding that responses in serial recall tend to be clustered around the position of the target item has bolstered positional-coding theories of serial order memory. In the present study, we show that this effect is confounded with another well-known finding—that responses in serial recall tend to also be clustered around the position of the prior recall (temporal clustering). The confound can be alleviated by conditioning each analysis on the positional accuracy of the previously recalled item. The revised analyses show that temporal clustering is much more prevalent in serial recall than is positional clustering. A simple associative chaining model with asymmetric neighboring, remote associations, and a primacy gradient can account for these effects. Using the same parameter values, the model produces reasonable serial position curves and captures the changes in item and order information across study-test trials. In contrast, a prominent positional coding model cannot account for the pattern of clustering uncovered by the new analyses.     

Effortful control in early childhood: continuity and change, antecedents, and implications for social development

The course, antecedents, and implications for social development of effortful control were examined in this comprehensive longitudinal study. Behavioral multitask batteries and parental ratings assessed effortful control at 22 and 33 months (N = 106). Effortful control functions encompassed delaying, slowing down motor activity, suppressing/initiating activity to signal, effortful attention, and lowering voice. Between 22 and 33 months, effortful control improved considerably, its coherence increased, it was stable, and it was higher for girls. Behavioral and parent-rated measures converged. Children's focused attention at 9 months, mothers' responsiveness at 22 months, and mothers' self-reported socialization level all predicted children's greater effortful control. Effortful control had implications for concurrent social development. Greater effortful control at 22 months was linked to more regulated anger, and at 33 months, to more regulated anger and joy and to stronger restraint.     

Organization of visuo-spatial serial memory: interaction of temporal order with spatial and temporal grouping

This study investigates whether memory for sequences of spatial locations can be represented hierarchically, that is, as successive groups containing the order of constituent locations. Two grouping manipulations are used: Temporal grouping, based on the verbal serial memory literature, and spatial grouping, based on recent empirical work on visuo-spatial serial memory. In Experiment 1, we examine the relationship between spatial grouping and temporal order and showed that recall performance increases when both temporal and spatial organization correlate, but decreases when they clash. Experiments 2 and 3 show that the latter result is confounded by differences in path length (length of spatial path defined by the locations) between conditions, and that no effect of the spatial organization is observed when path length is controlled for. In Experiment 4, an alternative method to spatial grouping, temporal grouping, is used to induce hierarchical organization. A recall advantage is found in the temporal grouping condition. The results suggest that hierarchical representations can be imposed on order information for visuo-spatial sequences, either when participants have pre-existing knowledge about the form of the path formed by the sequence or when temporal boundaries delimit chunks; that increased path length is the cause of the performance decrement observed when dots from separate spatial groups are presented successively; and that path length and more generally sequence characteristics should be taken into account in designing future research on visuo-spatial serial memory.     

Robust recollection rejection in the memory conjunction paradigm

The present research provides compelling evidence for recollection rejection in the memory conjunction paradigm. In Experiment 1, warnings provided at time of test were shown to reduce memory conjunction errors. Moreover, the authors found substantial evidence of recollection rejection and phantom recollection. In Experiment 2, the authors manipulated how often study items were presented. Participants were told that they could earn a cash payoff for being accurate. Recognition of conjunction lures was lower in the multiple presentation condition. However, the payoff manipulation did not significantly interact with item type. The authors obtained evidence of robust recollection rejection from 3 different dependent measures. Consistent with Experiment 1, they also found evidence of phantom recollection. These findings provide evidence that recollection rejection can be quite robust in the memory conjunction paradigm.     

Electrophysiological evidence of altered memory processing in children experiencing early deprivation

Associations between early deprivation and memory functioning were examined in 9- to 11-year-old children. Children who had experienced prolonged institutional care prior to adoption were compared to children who were adopted early from foster care and children reared in birth families. Measures included the Paired Associates Learning task from the Cambridge Neuropsychological Test and Automated Battery (CANTAB) and a continuous recognition memory task during which ERPs were also recorded. Children who experienced prolonged institutionalization showed deficits in both behavioral memory measures as well as an attenuated P300 parietal memory effect. Results implicate memory function as one of the domains that may be negatively influenced by early deprivation in the form of institutional care.     

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.     

Impaired retention is responsible for temporal order memory deficits in mild cognitive impairment

Temporal order memory, or remembering the order of events, is critical for everyday functioning and is difficult for patients with mild cognitive impairment (MCI). It is currently unclear whether these patients have difficulty acquiring and/or retaining such information and whether deficits in these patients are in excess of “normal” age-related declines. Therefore, the current study examined age and disease-related changes in temporal order memory as well as whether memory load played a role in such changes. Young controls (n = 25), older controls (n = 34), and MCI patients (n = 32) completed an experimental task that required the reconstruction of sequences that were 3, 4, or 5 items in length both immediately after presentation (i.e., immediate recall) and again after a 10-min delay (i.e., delayed recall). During the immediate recall phase, there was an effect of age largely due to reduced performance at the two longest span lengths. Older controls and MCI patients only differed during the five span (controls > MCI). During the delayed recall, however, there were significant effects of both age and MCI regardless of span length. In MCI patients, immediate recall was significantly correlated with measures of executive functioning, whereas delayed recall performance was only related to other memory tests. These findings suggest that MCI patients experience initial temporal order memory deficits at the point when information begins to exceed working memory capacity and become dependent on medial temporal lobe functioning. Longer-term deficits are due to an inability to retain information, consistent with the characteristic medial temporal lobe dysfunction in MCI.     

儿童早期工作记忆与数学学习的关系

以往研究认为工作记忆对数学学习很重要,但是以往工作记忆和早期数学学习的关系研究结果并不一致。本研究运用元分析的方法回顾了33篇独立研究,含307项相关系数作为效应值,总被试量为42423名平均年龄3~8岁的儿童,旨在探讨工作记忆的3个主成分PL(语音回路)、VSSP(视觉空间画板)、CE(中央执行)与数学学习不同方面之间的关系,以及样本年龄对工作记忆和数学学习相关程度的调节作用。结果显示:工作记忆与数学学习确实存在强相关,工作记忆子成分中,CE与数学学习平均相关的程度最强。并且,CE与数学学习不同方面之间的相关程度不存在显著差异,PL、VSSP与数运算的相关程度比数概念更强,存在显著差异。样本年龄对CE、PL与数学学习之间相关关系存在显著调节作用,对VSSP与数学学习之间的相关关系不存在显著调节作用。文献梳理还发现,以往研究对数学学习的考察,大都聚焦数概念、数运算的内容,未来研究需要关注几何与空间、测量等方面内容。     

Conscious recollection in autobiographical memory: an investigation in schizophrenia

Whether or not conscious recollection in autobiographical memory is affected in schizophrenia is unknown. The aim of this study was to address this issue using an experiential approach. An autobiographical memory enquiry was used in combination with the Remember/Know procedure. Twenty-two patients with schizophrenia and 22 normal subjects were asked to recall specific autobiographical memories from four lifetime periods and to indicate the subjective states of awareness associated with the recall of what happened, when and where. They gave Remember, Know or Guess responses according to whether they recalled these aspects of the event on the basis of conscious recollection, simply knowing, or guessing. Results showed that the frequency and consistency of Remember responses was significantly lower in patients than in comparison subjects. In contrast, the frequency of Know responses was not significantly different, whereas the frequency of patients' Guess responses was significantly enhanced. It is concluded that the frequency and consistency of conscious recollection in autobiographical memory is reduced in patients with schizophrenia.