Memory in autism spectrum disorder: a meta-analysis of experimental studies

To address inconsistencies in the literature on memory in Autism Spectrum Disorder (ASD), we report the first ever meta-analysis of short-term (STM) and episodic long-term (LTM) memory in ASD, evaluating the effects of type of material, type of retrieval and the role of inter-item relations. Analysis of 64 studies comparing individuals with ASD and typical development (TD) showed greater difficulties in ASD compared to TD individuals in STM (Hedges’ g=-0.53 [95%CI -0.90; -0.16], p=.005, I²=96%) compared to LTM (g=-0.30 [95%CI -0.42; -0.17], p<.00001, I²=24%), a small difficulty in verbal LTM (g=-0.21, p=.01), contrasting with a medium difficulty for visual LTM (g= -0.41, p=.0002) in ASD compared to TD individuals. We also found a general diminution in free recall compared to cued recall and recognition (LTM, free recall: g=-0.38, p<.00001, cued recall: g=-0.08, p=.58, recognition: g=-0.15, p=.16; STM, free recall: g=-0.59, p=.004, recognition: g=-0.33, p=.07). We discuss these results in terms of their relation to semantic memory. The limited diminution in verbal LTM and preserved overall recognition and cued recall (supported retrieval) may result from a greater overlap of these tasks with semantic long-term representations which are overall preserved in ASD. By contrast, difficulties in STM or free recall may result from less overlap with the semantic system or may involve additional cognitive operations and executive demands. These findings highlight the need to support STM functioning in ASD and acknowledge the potential benefit of using verbal materials at encoding and broader forms of memory support at retrieval to enhance performance

Alcohol-induced retrograde facilitation renders witnesses of crime less suggestible to misinformation

RATIONALE: Research has shown that alcohol can have both detrimental and facilitating effects on memory: intoxication can lead to poor memory for information encoded after alcohol consumption (anterograde amnesia) and may improve memory for information encoded before consumption (retrograde facilitation). This study examined whether alcohol consumed after witnessing a crime can render individuals less vulnerable to misleading post-event information (misinformation). METHOD: Participants watched a simulated crime video. Thereafter, one third of participants expected and received alcohol (alcohol group), one third did not expect but received alcohol (reverse placebo), and one third did not expect nor receive alcohol (control). After alcohol consumption, participants were exposed to misinformation embedded in a written narrative about the crime. The following day, participants completed a cued-recall questionnaire about the event. RESULTS: Control participants were more likely to report misinformation compared to the alcohol and reverse placebo group. CONCLUSION: The findings suggest that we may oversimplify the effect alcohol has on suggestibility and that sometimes alcohol can have beneficial effects on eyewitness memory by protecting against misleading post-event information

Brief targeted memory reactivation during the awake state enhances memory stability and benefits the weakest memories.

Reactivation of representations corresponding to recent experience is thought to be a critical mechanism supporting long-term memory stabilization. Targeted memory reactivation, or the re-exposure of recently learned cues, seeks to induce reactivation and has been shown to benefit later memory when it takes place during sleep. However, despite recent evidence for endogenous reactivation during post-encoding awake periods, less work has addressed whether awake targeted memory reactivation modulates memory. Here, we found that brief (50 ms) visual stimulus re-exposure during a repetitive foil task enhanced the stability of cued versus uncued associations in memory. The extent of external or task-oriented attention prior to re-exposure was inversely related to cueing benefits, suggesting that an internally-orientated state may be most permissible to reactivation. Critically, cueing-related memory benefits were greatest in participants without explicit recognition of cued items and remained reliable when only considering associations not recognized as cued, suggesting that explicit cue-triggered retrieval processes did not drive cueing benefits. Cueing benefits were strongest for associations and participants with the poorest initial learning. These findings expand our knowledge of the conditions under which targeted memory reactivation can benefit memory, and in doing so, support the notion that reactivation during awake time periods improves memory stabilization

Creating proactive interference in immediate recall: building a dog from a dart, a mop and a fig

[Abstract]: Phonemic codes are accorded a privileged role in most current models of immediate serial recall, although their effects are apparent in short-term proactive interference (PI) effects as well. The current research looks at how assumptions concerning distributed representation and distributed storage involving both semantic and phonemic codes might be operationalized to produce PI in a short-term cued recall task. The four experiments reported here attempted to generate the phonemic characteristics of a non-rhyming, interfering foil from unrelated filler items in the same list. PI was observed when a rhyme of the foil was studied or when the three phonemes of the foil were distributed across three studied filler items. The results suggest that items in short-term memory are stored in terms of feature bundles and that all items are simultaneously available at retrieval

Antiretroviral Non-Adherence is Associated With a Retrieval Profile of Deficits in Verbal Episodic Memory.

HIV-associated deficits in verbal episodic memory are commonly associated with antiretroviral non-adherence; however, the specific aspects of memory functioning (e.g., encoding, consolidation, or retrieval) that underlie this established relationship are not well understood. This study evaluated verbal memory profiles of 202 HIV+ participants who underwent a 30-day electronic monitoring of antiretroviral adherence. At the group level, non-adherence was significantly associated with lower scores on immediate and delayed passage recall and word list learning. Retention and recognition of passages and word lists were not related to adherence. Participants were then classified as having either a normal verbal memory profile, a "subcortical" retrieval profile (i.e., impaired free recall with relatively spared recognition), or a "cortical" encoding profile (e.g., cued recall intrusions) based on the Massman et al. ( 1990 ) algorithm for the California Verbal Learning Test. HIV+ participants with a classic retrieval deficit had significantly greater odds of being non-adherent than participants with a normal or encoding profile. These findings suggest that adherence to prescribed antiretroviral regimens may be particularly vulnerable to disruption in HIV+ individuals due to deficits in the complex process of efficiently accessing verbal episodic information with minimal cues. A stronger relationship between non-adherence and passage (vs. word list) recall was also found and may reflect the importance of contextual features in remembering to take medications. Targeted interventions for enhancing and supporting episodic memory retrieval processes may improve antiretroviral adherence and overall health outcomes among persons living with HIV

Binding an event to its source at encoding improves children\u27s source monitoring

Children learn information from a variety of sources and often remember the content but forget the source. While the majority of research has focused on retrieval mechanisms for such difficulties, the present investigation examines whether the way in which sources are encoded influences future source monitoring. In Study 1, 86 children aged 3 to 8 years participated in two photography sessions on different days. Children were randomly assigned to either the Difference condition (they were asked to pay attention to differences between the two events), the Memory control condition (asked to pay attention with no reference to differences), or the No-Instruction control (no special instructions were given). One week later, during a structured interview about the photography session, the 3-4 year-olds in the No-Instruction condition were less accurate and responded more often with \u27don\u27t know\u27 than the 7-8 year-olds. However, the older children in the Difference condition made more source confusions than the younger children suggesting improved memory for content but not source. In Study 2, the Difference condition was replaced by a Difference-Tag condition where details were pointed out along with their source (i.e., tagging source to content). Ninety-four children aged 3 to 8 years participated. Children in the Difference-Tag condition made fewer source-monitoring errors than children in the Control condition. The results of these two studies together suggest that binding processes at encoding can lead to better source discrimination of experienced events at retrieval and may underlie the rapid development of source monitoring in this age range

Organizational Processes Contribute to the Testing Effect in Free Recall

In educational contexts, tests not only assess what students know, they can also directly improve long-term retention of subject matter relative to restudying it. More importantly, the memorial advantage of testing is not limited to select information that was tested earlier. Research has shown that testing can serve as a versatile learning tool by enhancing the long-term retention of non-tested information that is conceptually related to previously tested information; stimulating the subsequent learning of new information; and permitting better transfer of learning to new knowledge domains. We further investigated the potential benefits of testing on learning by asking whether testing can also improve students\u27 learning and retention of the conceptual organization of study materials, and if so, whether processes involved in mentally organizing information during learning contribute to the memorial advantage of testing. In three experiments with categorized lists, we asked whether the testing effect in free recall is related to enhancements in organizational processing. In the first experiment, different groups of subjects studied a list either once or twice before a final criterial test or they studied the list once and took an initial recall test before the final test. Prior testing enhanced total recall of words and reduced false recall of extra-list intrusions relative to restudying. In addition, testing increased the number of categories accessed, the number of items recalled from within those categories, and improved category clustering. In two additional experiments, manipulating the organizational processing that occurred during initial study and test trials affected delayed recall and measures of output organization. Testing produced superior long-term retention when initial test conditions promoted the use of semantic relational information to guide episodic retrieval, and measures of category clustering and subjective organization were correlated with delayed recall. The results suggest that the benefit of testing in free recall learning arises, at least in part, because testing creates retrieval schemas based upon categorical knowledge and recollections of previous recall attempts that guide and facilitate episodic recall

Can multiple-choice testing potentiate new learning for text passages? A meta-cognitive approach to understanding the forward testing effect

A burgeoning area of research has begun to examine how retrieval practice can influence future learning that occurs after a test. In general, the extant literature has demonstrated a forward testing effect, in which prior testing enhances new learning. However, there is not a consensus as to the mechanism that leads to this phenomenon. In the present dissertation, I propose a metacognitive account, in which testing is purported to benefit subsequent learning by leading learners to better attend to and encode material. In particular, individuals who are tested gain valuable information about the nature and difficulty of upcoming tests, which helps guide their strategy use. Under this account, more difficult retrieval (e.g., recall) should lead to a greater metacognitive benefit than easier retrieval (e.g., multiple-choice). In Experiment 1, I compared prior cued-recall, prior multiple-choice, or no prior testing on performance for a criterial test of a text passage. Furthermore, I examined how the match between initial and criterial tests might determine whether testing influences new learning. In fact, prior cued-recall testing enhanced learning to a greater degree than prior multiple-choice testing (relative to no prior testing) regardless of criterial test format. Reading times for each text passage provided preliminary evidence for a metacognitive benefit of testing. Whereas reading times fell across the passages for individuals who were not tested, reading times remained stable in both testing conditions. In Experiments 2 and 3, I aimed to further investigate the metacognitive mechanism underlying the forward testing effect by requiring explicit judgments of learning (JOLs) prior to each testing (or non-testing) episode. Surprisingly, when JOLs were required, there was no forward testing effect observed in Experiment 2 (which included prior cued-recall, multiple-choice, or no-testing) or in Experiment 3 (which included a more difficult prior multiple-choice condition). In both Experiments 2 and 3, reading times remained stable across passages in each condition, although JOLs indicated less confidence in predicted performance in the tested conditions than in those who were not tested prior to the criterial test

Beliefs about the Minds of Others Influence How We Process Sensory Information

Attending where others gaze is one of the most fundamental mechanisms of social cognition. The present study is the first to examine the impact of the attribution of mind to others on gaze-guided attentional orienting and its ERP correlates. Using a paradigm in which attention was guided to a location by the gaze of a centrally presented face, we manipulated participants' beliefs about the gazer: gaze behavior was believed to result either from operations of a mind or from a machine. In Experiment 1, beliefs were manipulated by cue identity (human or robot), while in Experiment 2, cue identity (robot) remained identical across conditions and beliefs were manipulated solely via instruction, which was irrelevant to the task. ERP results and behavior showed that participants' attention was guided by gaze only when gaze was believed to be controlled by a human. Specifically, the P1 was more enhanced for validly, relative to invalidly, cued targets only when participants believed the gaze behavior was the result of a mind, rather than of a machine. This shows that sensory gain control can be influenced by higher-order (task-irrelevant) beliefs about the observed scene. We propose a new interdisciplinary model of social attention, which integrates ideas from cognitive and social neuroscience, as well as philosophy in order to provide a framework for understanding a crucial aspect of how humans' beliefs about the observed scene influence sensory processing

Testing effects in context memory

2011 Summer.Includes bibliographical references.Retrieving a previously learned piece of information can have profound positive effects on the later retention of such information. However, it is not clear if test-induced memory benefits are restricted to the specific information which was retrieved, or if they can generalize more completely to the full study episode. Two experiments investigated the role of retrieval practice on memory for both target and non-target contextual information. Experiment 1 used a remember-know task to assess the subjective quality of memory as a function of earlier retrieval practice or study. Additionally, memory for context information (target font color) from the initial study episode was assessed. Experiment 2 used paired associates to investigate the effect of testing on non-tested but associated contextual information. Successful retrieval practice, compared with study, resulted in large benefits in target, target-associated, and context information retention across both experiments. Moreover, successful retrieval practice was associated with a greater contribution of remember responses informing recognition decisions. The results suggest that retrieving information may serve to both boost item memory about a target and strengthen the bind between target and associated contextual information. In sum, the present study adds to an emerging literature that test-induced mnemonic benefits may "spill over" to non-tested information