Effect of levels-of-processing on rates of forgetting.

The levels-of-processing (LOP) framework, proposing that deep processing yields superior retention, has provided an important paradigm for memory research and a practical means of improving learning. However, the available levels-of-processing literature focuses on immediate memory performance. It is assumed within the LOP framework that deep processing will lead to slower forgetting than will shallow processing. However, it is unclear whether, or how, the initial level of processing affects the forgetting slopes over longer retention intervals. The present three experiments were designed to explore whether items encoded at qualitatively different LOP are forgotten at different rates. In the first two experiments, depth of processing was manipulated within-participants at encoding under deep and shallow conditions (semantic vs. rhyme judgement in Experiment 1; semantic vs. consonant-vowel pattern decision in Experiment 2). Recognition accuracy (d prime) was measured between-participants immediately after learning and at 30-min, 2-h, and 24-h delays. The third experiment employed a between-participants design, contrasting the rates of forgetting following semantic and phonological (rhyme) processing at immediate, 30-min, 2-h, and 6-h delays. Results from the three experiments consistently demonstrated a large effect size of levels of processing on immediate performance and a medium-to-large level effect size on delayed recognition, but crucially no LOP × delay group interaction. Analysis of the retention curves revealed no significant differences between the slopes of forgetting for deep and shallow processing. These results suggest that the rates of forgetting are independent of the qualitatively distinct encoding operations manipulated by levels of processing.

Forgetting rates of gist and peripheral episodic details in prose recall.

In a seminal study, Slamecka and McElree showed that the degree of initial learning of verbal material affected the intercepts but not the slopes of forgetting curves. However, more recent work has reported that memories for central events (gist) and memory for secondary details (peripheral) were forgotten at different rates over periods of days, with gist memory retained more consistently over time than details. The present experiments aimed to investigate whether qualitatively different types of memory scoring (gist vs. peripheral) are forgotten at different rates in prose recall. In three experiments, 232 participants listened to two prose narratives and were subsequently asked to freely recall the stories. In the first two experiments participants were tested repeatedly after days and a month, while in the third experiment they were tested only after a month to control for repeated retrieval. Memory for gist was higher than for peripheral details, which were forgotten at a faster rate over a month, with or without the presence of intermediate recall. Moreover, repeated retrieval had a significant benefit on both memory for gist and peripheral details. We conclude that the different nature of gist and peripheral details leads to a differential forgetting in prose free recall, while repeated retrieval does not have a differential effect on the retention of these different episodic details.

Long-term memory for spatial frequency: a non-replication.

Reports on stability of spatial frequency in short-term memory span have confirmed low-level perceptual memory mechanism in early visual processing. However, some studies have also claimed evidence for high-fidelity perceptual long-term storage of spatial frequency. We report an attempted replication of Magnussen et al. (Psychol Sci 14:74-76, 2003) where participants were asked to discriminate the spatial frequency of a reference grating from a test stimulus after intervals of 5 s or 24 h. Group thresholds after 24 h were significantly higher than after 5 s, therefore failing to support long-term storage of spatial frequency.

Rate of forgetting is independent of initial degree of learning.

It is commonly assumed that the rate of forgetting depends on initial degree of learning. Hence, comparison of forgetting across groups is usually carried out equating initial performance. However, these matching procedures add confounding variables. In four experiments, following Slamecka and McElree (1983, Exp 3), we challenge this assumption through manipulating initial acquisition by varying the number of presentations of the material and studying the effect on rate of subsequent forgetting. A set of 36 sentences was presented either visually or auditorily. Different participants were exposed to the material two, four or six times. Forgetting was measured by means of a cued recall test at three time-intervals (30 s, 1 day and 1 week in experiments 1 and 2; 30 s, 1 day, and 3 days in experiments 3 and 4). A different subset of 12 sentences was tested at each delay. The outcome of these experiments showed that the initial acquisition depends on number of learning trials. However, the rate of forgetting proved to be independent of initial acquisition. This pattern remains constant across modalities of presentation and of the number of learning trials. The conclusion is that forgetting does not depend on initial acquisition.

Righteous Adam, Sinister Eve.

The symbolism of laterality in images implies that the virtuous figure is represented on the right of the scene whereas the sinful character is depicted on the left. In portraits of male and female characters this has reflected and reinforced stereotypes and inequalities down the ages. Given these premises, we hypothesized that the prototypical representations of Adam and Eve, as a man and a woman conflated with notions of virtue and vice, would show a non-random arrangement. We tested this hypothesis, sampling artistic depictions of the Garden of Eden, from the twelth century to the present day in three separately-collected series of 100, 99, and 142 images respectively. Eve is depicted to Adam's left significantly more often than chance (between 70% and 83%), particularly in pre-1600 artworks. We interpret this asymmetry as reflecting the perceived lesser status of women in relation to men, since the allegorical incipit of humankind. We also provide experimental evidence that this asymmetry, although pervasive, has not been internalized by modern viewers. Cognitive sciences account for this spatial asymmetry in terms of preference for figures placed within the left visual field of the observer, i.e., within the right space of the objective scene.

Forming and updating vaccination beliefs: does the continued effect of misinformation depend on what we think we know?

People may cling to false facts even in the face of updated and correct information. The present study confronted misconceptions about the measles, mumps and rubella vaccine and a novel, fictitious Zika vaccine. Two experiments are reported, examining misconceptions as motivated by a poor risk understanding (Experiment 1, N = 130) or the exposure to conspiracy theories (Experiment 2, N = 130). Each experiment featured a Misinformation condition, wherein participants were presented with fictitious stories containing some misinformation (Experiment 1) and rumours focused on conspiracy theories (Experiment 2) that were later retracted by public health experts and a No misinformation condition, containing no reference to misinformation and rumours. Across experiments, participants were more hesitant towards vaccines when exposed to stories including vaccine misinformation. Notwithstanding, our results suggest a positive impact of a trusted source communicating the scientific consensus about vaccines. Zika virus represents a particular case showing how missing information can easily evolve into misinformation. Implications for effective dissemination of information are discussed.

A reappraisal of acute doses of benzodiazepines as a model of anterograde amnesia.

OBJECTIVE: Acute administration of benzodiazepines is considered a pharmacological model of general organic anterograde amnesias (OAA). We sought to determine which type of amnesia these drugs best model by comparing the effects of diazepam with those reported in amnesiacs regarding working memory capacity (WMC), susceptibility to retroactive interference (RI), and accelerated forgetting. METHODS: In this double-blind, parallel-group design study, 30 undergraduates were randomly allocated to acute oral treatments with 15 mg diazepam or placebo. WMC and story recall were assessed pre- and post-treatment. Story presentation was succeeded by 10 min of RI (spotting differences in pictures) or minimal RI (doing nothing in a darkened room). Delayed story recall was assessed under diazepam and 7 days later in a drug-free session to assess accelerated forgetting. RESULTS: Recall of stories encoded under diazepam, whether reactivated or not, was severely impaired (anterograde amnesia). However, diazepam did not impair WMC, increase susceptibility to RI, or accelerate forgetting. CONCLUSIONS: Diazepam's amnestic effects mirror those in patients with probable severe medial temporal damage, mostly restricted to initial consolidation and differ from other OAA (Korsakoff syndrome, frontal, transient epileptic, posttraumatic amnesia, and most progressive amnesias) in terms of WMC, susceptibility to RI and accelerated forgetting.

Challenges to recruitment of participants with MCI in a multicentric neuropsychological study.

BACKGROUND: Data on recruitment of Mild Cognitive Impairment (MCI) samples are seldom reported and this issue can be an important source of research waste. AIM: To describe the recruitment challenges and reasons for non-eligibility faced during a bi-centre clinical study assessing the predictive value of a neuropsychological battery of the progression to dementia. METHODS: Potential MCI participants were identified from databases of the two memory clinics based in Milan (Italy) and invited to the screening assessment. RESULTS: About 50% of the cases initially identified were ineligible according to inclusion/exclusion criteria and the two sites took 22 months to recruit the planned 150 people. The main reasons for non-eligibility were the MMSE score (41%), age (14%), presence of cerebrovascular disorders (9%), perceptual deficits (6%), neurological (6%) or psychiatric (4%) comorbidities and low education (5%). CONCLUSION: Awareness of the reasons for exclusion and of the time needed to recruit the planned sample would provide hints for the planning of future studies on MCI.

Effect of test instructions: The example of the pantomime production task.

The production of pantomime is a sensible task to detect praxis deficits. It is usually assessed by presenting objects visually or by verbal command. Verbal instructions are given either by providing the name of the object (e.g., "Show me how to use a pen") or by requiring the object function (e.g., "Show me how to write"). These modes of testing are used interchangeably. The aim of this study is to investigate whether the different instructions generate different performances. Fifty-one healthy participants (17-89 years old) were assessed on three pantomime production tasks differing for the instruction given: two with verbal instructions (Pantomime by Name and Pantomime by Function) and one with the object visually presented (Pantomime by Object). Results showed that Pantomime by Function produced the poorest performance and the highest frequency of Body Parts as Tool (BPT) errors, suggesting that the way the instructions are given may determine the performance in a task. Nuances in test instructions could result in misleading outcome.

Profiles of cognitive impairment in the continuum from normal cognition to Alzheimer's clinical syndrome: Contributions of the short-term memory binding tests.

BACKGROUND: Short-term memory binding (STMB) tests assess conjunctive binding, in which participants should remember the integration of features, such as shapes (or objects) and colors, forming a unique representation in memory. In this study, we investigated two STMB paradigms: change detection (CD) and free recall (FR). OBJECTIVE: To investigate the cognitive profile in the CD and FR tasks of three diagnostic groups: cognitively unimpaired (CU), mild cognitive impairment (MCI), and Alzheimer's clinical syndrome (ACS). In addition, we aimed to calculate and compare the accuracy of the CD and FR tasks to identify MCI and ACS. METHODS: Participants were 24 CU, 24 MCI, and 37 ACS. The cognitive scores of the clinical groups were compared using analysis of variance (ANOVA) and receiver-operating characteristic (ROC) analyses were carried out to verify the accuracy of the STMB tasks. RESULTS: In the CD task, CU was different from MCI and ACS (CU > MCI = ACS), while in the FR task all groups were different (CU > MCI > ACS). The ROC analyses showed an area under the curve (AUC) of 0.855 comparing CU with MCI for the CD task and 0.975 for the FR. The AUC comparing CU and ACS was 0.924 for the CD and 0.973 for the FR task. The FR task showed better accuracy to identify MCI patients, and the same accuracy to detect ACS. CONCLUSION: The present findings indicate that impairments in CD and FR of bound representations are features of the cognitive profiles of MCI and ACS patients.

The effects of source expertise and trustworthiness on recollection: the case of vaccine misinformation.

Designing effective communication strategies for correcting vaccines misinformation requires an understanding of how the target group might react to information from different sources. The present study examined whether erroneous inferences about vaccination could be effectively corrected by a perceived credible (i.e. expert or trustworthy) source. Two experiments are reported using a standard continued influence paradigm, each featuring two correction conditions on vaccine misinformation. Participants were presented with a story containing a piece of information that was later retracted by a perceived credible or not so credible source. Experiment 1 showed that providing a correction reduced participants' use of the original erroneous information, yet the overall reliance on misinformation did not significantly differ between the low- and high-expertise correction groups. Experiment 2 revealed that a correction from a high-trustworthy source decreased participants' reliance on misinformation when making inferences; nonetheless, it did not positively affect the reported intent to vaccinate one's child. Overall, source trustworthiness was more relevant than source expertise.

Parents' beliefs in misinformation about vaccines are strengthened by pro-vaccine campaigns.

The main objective of this study was to determine whether one of the most commonly employed pro-vaccination strategies based on the "myths vs. facts" format can be considered an effective tool to counter vaccines misinformation. Sixty parents were randomly presented with either a control message or a booklet confronting some common myths about vaccines with a number of facts. Beliefs in the autism/vaccines link and in vaccines side effects, along with intention to vaccinate one's child, were evaluated both immediately after the intervention and after a 7-day delay to reveal possible backfire effects. Data provided support for the existence of backfire effects associated with the use of the myths vs. facts format, with parents in this condition having stronger vaccine misconceptions over time compared with participants in the control condition. The myths vs. facts strategy proved to be ineffective. Efforts to counter vaccine misinformation should take into account the many variables that affect the parents' decision-making.

Unawareness for Motor Impairment and Distorted Perception of Task Difficulty.

OBJECTIVES: Anosognosia for motor impairment is a complex syndrome that can manifest itself under different forms, guiding patients' behavior and task decisions. However, current diagnostic tools tend to evaluate only more explicit aspects of anosognosia (asking the patients about their motor abilities) and fail to address more subtle features of awareness. We have developed a new assessment measure, the ECT (Errand Choice Test), where patients are asked to judge task difficulty rather than estimate their own impairment. METHODS: We assessed awareness in a group of 73 unilateral left- and right-brain damaged (30 LBD and 43 RBD, respectively) patients by means of the VATAm, which explicitly requires them to evaluate their own motor abilities, and the ECT. A control group of 65 healthy volunteers was asked to perform the ECT under two conditions: Current condition (i.e., using both hands) and Simulated conditions (i.e., simulating hemiplegia). RESULTS: A total of 27% of the patients showed different performance on the VATAm and ECT, 21% of the patients showing lack of awareness only on VATAm and 6% only on ECT. Moreover, despite the ECT identified a higher frequency of anosognosia after RBD (33.3%) than LBD (27.6%), this hemispheric asymmetry was not significant. Remarkably, anosognosic patients performed very similarly to controls in the "current condition", suggesting that anosognosic patients' ability to perceive the complexity of each task per se is not altered. CONCLUSION: Different methods may be able to tackle different aspects of awareness and the ECT proved to be able to detect less evident forms of awareness. (JINS, 2018, 24, 45-56).

A transcultural cognitive marker of Alzheimer's Disease.

OBJECTIVE: Temporary binding (TB) is sensitive and specific to Alzheimer's Disease (AD), is not affected by age, repeated testing or level of education. Hence, TB is useful to assess patients with very different socio-cultural backgrounds. However, the current computerised version of the test is not suitable for use in clinical settings. The aim of this study was to investigate whether a clinically friendly version of the TB task results in overlapping outcomes compared to the computerised version. METHODS: A newly devised Flash-card version of the TB assesses temporary visual binding for arrays of stimuli such as shapes (polygons), colours, or combinations of shapes and colours. In Experiment 1, this version was compared with the laboratory computerised version. In Experiment 2, 33 AD patients and 33 matched controls, recruited from various geriatric centres in Romania, were assessed with the new TB test and with Free and Cued Selective Reminding test. RESULTS: The results with the Flash-card version of the TB test were comparable to those obtained with the computerised version. TB was not affected by age, but it was impaired by AD. The sensitivity and specificity of the new TB test were found to be greater than those achieved by a Selective Reminding test. CONCLUSIONS: TB deficits may be conceived as a fundamental marker of AD. The Flash-card version is suitable for clinical use also in primary care facilities and in intervention trials, requires minimal training for administration and scoring, is quick to administer, non-invasive, inexpensive, and facilitates cross-cultural studies. Copyright © 2016 John Wiley & Sons, Ltd.

The effect of age on the FCSRT-IR and temporary visual memory binding.

ABSTRACTBackground:Cognitive markers of early Alzheimer's disease (AD) should be sensitive and specific to memory impairments that are not associated with healthy cognitive aging. In the present study, we investigated the effect of healthy cognitive aging on two proposed cognitive markers of AD: the Free and Cued Selective Reminding Task with Immediate Recall (FCSRT-IR) and a temporary visual memory binding (TMB) task. METHOD: Free recall and the cost of holding bound information in visual memory were compared between 24 younger and 24 older participants in a mixed, fully counterbalanced experiment. RESULTS: A significant effect of age was observed on free recall in the FCSRT-IR only and not on the cost of binding in the TMB task. CONCLUSIONS: Of these two cognitive markers, the TMB task is more likely to be specific to memory impairments that are independent of age.

Fly on the right: Lateral preferences when choosing aircraft seats.

A small preference has been observed for people to choose seats on the left of aircraft when booking via an online system. Although this is consistent with pseudoneglect-the known leftward bias in perception and representation-rightward preferences have been commonly observed in seating selection tasks in other environments. Additionally, the previous research in aircraft seating was unable to dissociate a bias to one side of the screen from a bias to one side of the cabin of the aircraft. Here, we present a study in which participants were asked to select seats for a range of fictional flights. They demonstrated a preference for seats on the right of the cabin, irrespective of whether the right of the cabin appeared to either the right or the left of the screen, a preference for seats towards the front of the aircraft and a preference to favour window and aisle seats. This suggests, in contrast to previous research, that participants demonstrated a rightward lateral bias to representations of an aircraft. These results may have implications for our understanding of asymmetries in cognition as well as having potentially important practical implications for airlines.

Wakeful rest promotes the integration of spatial memories into accurate cognitive maps.

Flexible spatial navigation, e.g. the ability to take novel shortcuts, is contingent upon accurate mental representations of environments-cognitive maps. These cognitive maps critically depend on hippocampal place cells. In rodents, place cells replay recently travelled routes, especially during periods of behavioural inactivity (sleep/wakeful rest). This neural replay is hypothesised to promote not only the consolidation of specific experiences, but also their wider integration, e.g. into accurate cognitive maps. In humans, rest promotes the consolidation of specific experiences, but the effect of rest on the wider integration of memories remained unknown. In the present study, we examined the hypothesis that cognitive map formation is supported by rest-related integration of new spatial memories. We predicted that if wakeful rest supports cognitive map formation, then rest should enhance knowledge of overarching spatial relations that were never experienced directly during recent navigation. Forty young participants learned a route through a virtual environment before either resting wakefully or engaging in an unrelated perceptual task for 10 min. Participants in the wakeful rest condition performed more accurately in a delayed cognitive map test, requiring the pointing to landmarks from a range of locations. Importantly, the benefit of rest could not be explained by active rehearsal, but can be attributed to the promotion of consolidation-related activity. These findings (i) resonate with the demonstration of hippocampal replay in rodents, and (ii) provide the first evidence that wakeful rest can improve the integration of new spatial memories in humans, a function that has, hitherto, been associated with sleep.

Memory binding and white matter integrity in familial Alzheimer's disease.

Binding information in short-term and long-term memory are functions sensitive to Alzheimer's disease. They have been found to be affected in patients who meet criteria for familial Alzheimer's disease due to the mutation E280A of the PSEN1 gene. However, only short-term memory binding has been found to be affected in asymptomatic carriers of this mutation. The neural correlates of this dissociation are poorly understood. The present study used diffusion tensor magnetic resonance imaging to investigate whether the integrity of white matter structures could offer an account. A sample of 19 patients with familial Alzheimer's disease, 18 asymptomatic carriers and 21 non-carrier controls underwent diffusion tensor magnetic resonance imaging, neuropsychological and memory binding assessment. The short-term memory binding task required participants to detect changes across two consecutive screens displaying arrays of shapes, colours, or shape-colour bindings. The long-term memory binding task was a Paired Associates Learning Test. Performance on these tasks were entered into regression models. Relative to controls, patients with familial Alzheimer's disease performed poorly on both memory binding tasks. Asymptomatic carriers differed from controls only in the short-term memory binding task. White matter integrity explained poor memory binding performance only in patients with familial Alzheimer's disease. White matter water diffusion metrics from the frontal lobe accounted for poor performance on both memory binding tasks. Dissociations were found in the genu of corpus callosum which accounted for short-term memory binding impairments and in the hippocampal part of cingulum bundle which accounted for long-term memory binding deficits. The results indicate that white matter structures in the frontal and temporal lobes are vulnerable to the early stages of familial Alzheimer's disease and their damage is associated with impairments in two memory binding functions known to be markers for Alzheimer's disease.

Adult developmental trajectories of pseudoneglect in the tactile, visual and auditory modalities and the influence of starting position and stimulus length.

Pseudoneglect is a tendency to pay more attention to the left side of space, typically demonstrated on tasks like visuo-spatial line bisection, tactile rod bisection and the mental representation of numbers. The developmental trajectory of this bias on these three tasks is not fully understood. In the current study younger participants aged between 18 and 40 years of age and older participants aged between 55 and 90 years conducted three spatial tasks: (1) visuospatial line bisection - participants were asked to bisect visually presented lines of different lengths at the perceived midpoint; (2) touch-driven tactile rod bisection in the absence of vision - participants were asked to feel the length of a wooden rod with their index finger and bisect the rod at the perceived centre; and (3) mental number line bisection in the absence of vision - participants were asked to listen to a pair of numbers and respond with the numerical midpoint between the pair. The results showed that both younger and older participants demonstrated pseudoneglect (leftward biases) in the visual, tactile and mental number line tasks and that the magnitude of pseudoneglect for each group was influenced by physical or mentally represented starting side (start left versus start right) and stimulus length. We provide an exploration of pseudoneglect in younger and older adults in different tasks that vary in the degree to which mental representations are accessed and argue that pseudoneglect is a result of a right hemisphere attentional orienting process that is retained throughout adulthood. Our results indicate that, contrary to some current models of cognitive ageing, asymmetrical patterns of hemispheric activity may occur in older age.