A pilot study examining the impact of lithium treatment and responsiveness on mnemonic discrimination in bipolar disorder

INTRODUCTION

Mnemonic discrimination (MD), the ability to discriminate new stimuli from similar memories, putatively involves dentate gyrus pattern separation. Since lithium may normalize dentate gyrus functioning in lithium-responsive bipolar disorder (BD), we hypothesized that lithium treatment would be associated with better MD in lithium-responsive BD patients.

METHODS

BD patients (N = 69; NResponders = 16 [23 %]) performed the Continuous Visual Memory Test (CVMT), which requires discriminating between novel and previously seen images. Before testing, all patients had prophylactic lithium responsiveness assessed over ≥1 year of therapy (with the Alda Score), although only thirty-eight patients were actively prescribed lithium at time of testing (55 %; 12/16 responders, 26/53 nonresponders). We then used computational modelling to extract patient-specific MD indices. Linear models were used to test how (A) lithium treatment, (B) lithium responsiveness via the continuous Alda score, and (C) their interaction, affected MD.

RESULTS

Superior MD performance was associated with lithium treatment exclusively in lithium-responsive patients (Lithium x AldaScore β = 0.257 [SE 0.078], p = 0.002). Consistent with prior literature, increased age was associated with worse MD (β = -0.03 [SE 0.01], p = 0.005).

LIMITATIONS

Secondary pilot analysis of retrospectively collected data in a cross-sectional design limits generalizability.

CONCLUSION

Our study is the first to examine MD performance in BD. Lithium is associated with better MD performance only in lithium responders, potentially due to lithium's effects on dentate gyrus granule cell excitability. Our results may influence the development of behavioural probes for dentate gyrus neuronal hyperexcitability in BD.

Visual memory and alcohol use in a middle-aged birth cohort

Light and moderate alcohol use has been reported to be associated with both impaired and enhanced cognition. The purpose of this study was to explore whether there was a linear relationship between visual memory and alcohol consumption in males and females in a large middle-aged birth cohort population in cross-sectional and longitudinal settings. Data were collected from 5585 participants completing 31-year (1997-1998) and 46-year (2012-2014) follow-ups including Paired Associate Learning (PAL) test at 46-years follow-up. The participants were originally from 12,231 study population of the Northern Finland Birth Cohort 1966 (NFBC1966). The PAL test was conducted to assess visual memory. Reported alcohol use was measured as total daily use of alcohol, beer, wine, and spirits converted into grams and as frequency and amount of use of beer, wine, and spirits. The total daily alcohol use was not associated with reduced visual memory. The frequency of use of beer and wine in males was associated with better visual memory in cross-sectional and longitudinal settings. Using six or more servings of spirits was associated with worse visual memory in males in cross-sectional and longitudinal settings. Using six or more servings of spirits was associated with worse visual memory in males in cross-sectional and longitudinal setting. The study suggested a lack of a linear association between drinking and visual memory in the middle-aged population.

Neurodevelopment effects of early life bisphenol-A exposure on visual memory: Insights into recovery dynamics

Bisphenol A (BPA), a ubiquitous endocrine disruptor, is implicated in the cognitive deficits observed in both children and animals. Especially, BPA-induced spatial memory deterioration during the whole development phase of rodents has been well delineated. However, whether BPA exposure on the different development phases exerts similar effects on the prefrontal cortex (PFC) dependent visual memory is still elusive. Here, we chose two exposure windows, the whole gestation and lactation phases (E0∼P21) and the whole juvenile and adolescent phases (P22∼P60), for exposing rats to BPA. The visual memory of those rats was accessed by object recognition testing in the open field after BPA exposure and a constant recovery interval. The results revealed a substantial decline of visual memory under both exposure conditions, accompanied by an increase in anxiety-like behavior in BPA-exposed rats. Notably, after a 20-day recovery period, those behavioral changes induced by BPA exposure during P22∼60, not E0∼P21, were reversed compared to the control rats. According to morphological analysis of those rats after recovery, we found that the spine density of pyramidal neurons in the PFC were significant decreased in rats with BPA exposure during E0∼P21 and there was no difference between rats with or without BPA exposure during P22∼P60. Additionally, a similar change trend in excitatory receptors expression was observed under both exposure conditions. After an additional 20 days of recovery, the behavioral changes in rats with perinatal BPA exposure reverted to the normal status. Our present findings illuminate the dynamic effects of BPA on PFC-dependent functions across two crucial early developmental stages of life.

Selective short-term memory impairment for verbalizable visual objects in children with Developmental Language Disorder

BACKGROUND

Developmental language disorder (DLD) affects the ability to acquire and make use of native language. Possible underlying cognitive mechanisms are related to memory functions.

AIMS

The aim was examination of the relationship between visual short-term memory of objects as well as audiovisual short-term memory, and particular nonverbal and language abilities.

METHODS AND PROCEDURES

The study included 7-9-year-old children with DLD and matched control group. Participants completed the Language Development Test, the Stanford-Binet IQ scale (SB5), and two short-term memory tasks: immediate recall of the visually presented pictograms and immediate recall of audiovisually presented sequences of syllables.

OUTCOMES AND RESULTS

The results revealed diminished levels of short-term visual memory for objects as well as audiovisual memory in children with DLD. However, there were no group differences in the control task of WM.

CONCLUSIONS AND IMPLICATIONS

Results supported the idea of diminished abilities in children with DLD to perform mental operations on verbalizable visual objects. Importantly non-verbal working memory ability, which cannot easily be supported by verbal representations, is at typical levels. This suggests that verbalization ability should be taken into account in the assessment of seemingly non-verbal cognitive functions among children with DLD.

A Role for Visual Memory in Vocabulary Development: A Systematic Review and Meta-Analysis

Although attention and early associative learning in preverbal children is predominantly driven by rapid eye-movements in response to moving visual stimuli and sounds/words (e.g., associating the word "bottle" with the object), the literature examining the role of visual attention and memory in ongoing vocabulary development across childhood is limited. Thus, this systematic review and meta-analysis examined the association between visual memory and vocabulary development, including moderators such as age and task selection, in neurotypical children aged 2-to-12 years, from the brain-based perspective of cognitive neuroscience. Visual memory tasks were classified according to the visual characteristics of the stimuli and the neural networks known to preferentially process such information, including consideration of the distinction between the ventral visual stream (processing more static visuo-perceptual details, such as form or colour) and the more dynamic dorsal visual stream (processing spatial temporal action-driven information). Final classifications included spatio-temporal span tasks, visuo-perceptual or spatial concurrent array tasks, and executive judgment tasks. Visuo-perceptual concurrent array tasks, reliant on ventral stream processing, were moderately associated with vocabulary, while tasks measuring spatio-temporal spans, associated with dorsal stream processing, and executive judgment tasks (central executive), showed only weak correlations with vocabulary. These findings have important implications for health professionals and researchers interested in language, as they advocate for the development of more targeted language learning interventions that include specific and relevant aspects of visual processing and memory, such as ventral stream visuo-perceptual details (i.e., shape or colour).

Accelerometry measures of physical activity and sedentary behavior: Associations with cognitive functioning in MS

BACKGROUND

Cognitive dysfunction is a pervasive symptom of multiple sclerosis (MS). Correlational evidence on the relationships between physical activity, sedentary behavior, and cognition has been mixed and limited to a few activity measures. The collinearity of accelerometry-based metrics has precluded an assessment of the full activity spectrum. Here, we aimed to examine the rich set of activity measures using analytic approaches suitable for collinear metrics. We investigated the combination of physical activity, sedentary, and clinicodemographic measures that explain the most variance in composite scores of working memory/processing speed, visual memory, and verbal memory.

METHODS

We analyzed baseline accelerometry and neuropsychological data (n = 80) from a randomized controlled trial of pedometer tracking. Using partial least squares regression (PLSR), we built three models to predict latent scores on the three domains of cognition using 12 activity metrics, sex, education, and Expanded Disability Status Scale (EDSS) scores. Significance was assessed using linear regression models with model component scores as predictors and cognitive composites as outcomes.

RESULTS

The latent component was significant for working memory/processing speed but was not significant for visual memory and verbal memory after Bonferroni correction. Working memory/processing speed was positively associated with average kilocalories, moderate-to-vigorous physical activity (MVPA), steps, and sex (i.e., higher scores in males) and negatively related to duration of long sedentary bouts and EDSS.

CONCLUSIONS

These findings suggest that increasing overall energy expenditure through walking and MVPA, while decreasing prolonged sedentary time may positively benefit working memory/processing speed in people with MS.

TRIAL REGISTRATION

This RCT #NCT03244696 was registered on Clinicaltrials.gov (https://www.

CLINICALTRIALS

gov/ct2/show/NCT03244696).

Is there an association between daytime napping, cognitive function, and brain volume? A Mendelian randomization study in the UK Biobank

OBJECTIVES

Daytime napping has been associated with cognitive function and brain health in observational studies. However, it remains elusive whether these associations are causal. Using Mendelian randomization, we studied the relationship between habitual daytime napping and cognition and brain structure.

METHODS

Data were from UK Biobank (maximum n = 378,932 and mean age = 57 years). Our exposure (daytime napping) was instrumented using 92 previously identified genome-wide, independent genetic variants (single-nucleotide polymorphisms, SNPs). Our outcomes were total brain volume, hippocampal volume, reaction time, and visual memory. Inverse-variance weighted was implemented, with sensitivity analyses (Mendelian randomization-Egger and Weighted Median Estimator) for horizontal pleiotropy. We tested different daytime napping instruments to ensure the robustness of our results.

RESULTS

Using Mendelian randomization, we found an association between habitual daytime napping and larger total brain volume (unstandardized ß = 15.80 cm3 and 95% CI = 0.25; 31.34) but not hippocampal volume (ß = -0.03 cm3 and 95% CI = -0.13;0.06), reaction time (expß = 1.01 and 95% CI = 1.00;1.03), or visual memory (expß = 0.99 and 95% CI = 0.94;1.05). Additional analyses with 47 SNPs (adjusted for excessive daytime sleepiness), 86 SNPs (excluding sleep apnea), and 17 SNPs (no sample overlap with UK Biobank) were largely consistent with our main findings. No evidence of horizontal pleiotropy was found.

CONCLUSIONS

Our findings suggest a modest causal association between habitual daytime napping and larger total brain volume. Future studies could focus on the associations between napping and other cognitive or brain outcomes and replication of these findings using other datasets and methods.

Dual-stage cognitive assessment: a two-stage screening for cognitive impairment in primary care

BACKGROUND

Aging population has led to an increased proportion of older adults and cognitively impaired. We designed a brief and flexible two-stage cognitive screening scale, the Dual-Stage Cognitive Assessment (DuCA), for cognitive screening in primary care settings.

METHOD

In total, 1,772 community-dwelling participants were recruited, including those with normal cognition (NC, n = 1,008), mild cognitive impairment (MCI, n = 633), and Alzheimer's disease (AD, n = 131), and administered a neuropsychological test battery and the DuCA. To improve performance, the DuCA combines visual and auditory memory tests for an enhanced memory function test.

RESULTS

The correlation coefficient between DuCA-part 1 and DuCA-total was 0.84 (P < 0.001). The correlation coefficients of DuCA-part 1 with Addenbrooke's Cognitive Examination III (ACE-III) and Montreal Cognitive Assessment Basic (MoCA-B) were 0.66 (P < 0.001) and 0.85 (P < 0.001), respectively. The correlation coefficients of DuCA-total with ACE-III and MoCA-B were 0.78 (P < 0.001) and 0.83 (P < 0.001), respectively. DuCA-Part 1 showed a similar discrimination ability for MCI from NC (area under curve [AUC] = 0.87, 95%CI 0.848-0.883) as ACE III (AUC = 0.86, 95%CI 0.838-0.874) and MoCA-B (AUC = 0.85, 95%CI 0.830-0.868). DuCA-total had a higher AUC (0.93, 95%CI: 0.917-0.942). At different education levels, the AUC was 0.83-0.84 for DuCA-part 1, and 0.89-0.94 for DuCA-total. DuCA-part 1 and DuCA-total's ability to discriminate AD from MCI was 0.84 and 0.93, respectively.

CONCLUSION

DuCA-Part 1 would aid rapid screening and supplemented with the second part for a complete assessment. DuCA is suited for large-scale cognitive screening in primary care, saving time and eliminating the need for extensively training assessors.

The relationship between visual memory and spatial intelligence with students' academic achievement in anatomy

INTRODUCTION

Academic achievement is influenced by various factors. Spatial intelligence and visual memory are among the factors that seem to be related to learning anatomy. The aim of this study was to investigate the relationship between visual memory and spatial intelligence with students' academic achievement in anatomy.

METHODS

The present study is a descriptive cross-sectional study. All medical and dental students who had chosen anatomy courses (Semester 3 medicine and 2 dentistry) were the target population (n=240). The study tools were Jean-Louis Sellier 's visual memory test to determine visual memory and ten questions from Gardner Spatial Intelligence Questionnaire were employed to assess spatial intelligence. The tests were performed at the beginning of the semester and its relationship with the academic achievement scores of the anatomy course was examined. Data were analyzed by descriptive statistics, independent t-test, Pearson correlation and multiple linear regression.

RESULTS

Data of 148 medical students and 85 dental students were analyzed. The mean score of visual memory in medical students (17.1±5.3) was significantly higher than dental students (14.3±4.6) (P-value <0.001). But the mean score of spatial intelligence (31.5±5.9) was not significantly different between medical and dental students (31.9±4.9) (P-value=0.56). Pearson correlation coefficient showed that in medical students there was a direct relationship between visual memory score and spatial intelligence score with scores of anatomy courses (P-value<0.05). Moreover, in dental students, there was a direct relationship between the score of anatomical sciences with the score of visual memory (P-value=0.01) and the score of spatial intelligence (P-value=0.003).

CONCLUSION

The results of this study showed that there is a significant relationship between spatial intelligence and visual memory with learning anatomy and planning to enhance these characteristics can be fruitful in students. It is suggested that Visual memory and spatial intelligence should be considered for student admission, especially in the fields of medicine and dentistry.

Independent and interactive effect of type 2 diabetes and hypertension on memory functions in middle aged adults

BACKGROUND

The study distinguishes the effect of type 2 diabetes and hypertension on cognitive functions when the two diseases are alone or when they occur together, compared to healthy individuals.

METHODS

A total of 143 middle-aged adults were screened using the Wechsler Memory Scale - Revised psychometric test (verbal memory, visual memory, attention/concentration and delayed memory). Participants were divided into four groups based on their diseases: patients with type 2 diabetes (36), patients with hypertension (30), patients having both diseases (33), and healthy controls (44).

RESULTS

This study found no differences among investigated groups in verbal and visual memory, however, hypertension and both-disease group performed unfavorably compared to patients with diabetes and to healthy individuals in attention/concentration and delayed memory.

CONCLUSIONS

The findings of this study suggest that there is a relationship between hypertension and cognitive dysfunction, whereas type 2 diabetes without consequences was not proved to have an association with cognitive decline in middle-aged people.

Judgments of learning reveal conscious access to stimulus memorability

Despite the massive capacity of visual long-term memory, individuals do not successfully encode all visual information they wish to remember. This variability in encoding success has been traditionally ascribed to fluctuations in individuals' cognitive states (e.g., sustained attention) and differences in memory encoding processes (e.g., depth of encoding). However, recent work has shown that a considerable amount of variability in encoding success stems from intrinsic stimulus properties that determine the ease of encoding across individuals. While researchers have identified several perceptual and semantic properties that contribute to stimulus memorability, much remains unknown, including whether individuals are aware of the memorability of stimuli they encounter. In the present study, we investigated whether individuals have conscious access to the memorability of real-world stimuli while forming self-referential judgments of learning (JOL) during explicit memory encoding (Experiments 1A-B) and when asked about the perceived memorability of a stimulus in the absence of attempted encoding (Experiments 2A-B). We found that JOLs and perceived memorability estimates (PME) were consistent across individuals and predictive of memorability, confirming that individuals can access memorability with or without stimulus encoding. At the same time, access to memorability was not comprehensive. We found that individuals unexpectedly remembered and forgot consistent sets of stimuli as well. When we compared access to memorability between JOLs and PMEs, we found that individuals had more access during JOLs. Thus, our findings demonstrate that individuals have partial access to stimulus memorability and that explicit encoding increases the amount of access that is available.

Disorder-specific impaired neurocognitive function in major depression and generalized anxiety disorder

BACKGROUND

Generalized anxiety disorder (GAD) and major depressive disorder (MDD) are both highly prevalent and comorbid psychiatric disorders. Neurocognitive dysfunction has been commonly found in MDD, but the findings in GAD are inconsistent. Few studies have directly compared cognitive performance between GAD and MDD. Therefore, the present study aimed to reveal the similar and distinct cognitive impairments between both disorders.

METHODS

Three non-overlapping and non-comorbid groups were enrolled in the current study including patients with GAD (n = 37), MDD (n = 107) and healthy controls (n = 74). Levels of anxiety and depression were assessed using the Hamilton Anxiety Rating Scale (HAMA) and the Hamilton Depression Rating Scale (HAMD) respectively. The Cambridge Neuropsychological Test Automated Battery (CANTAB) was used to compare the cognitive performance, including sustained attention, visual memory, executive functions and learning.

RESULTS

Both MDD and GAD groups demonstrated common significant deficits in sustained attention, visual memory, working memory and learning when compared to healthy controls. Despite the similarities, the MDD group had significantly greater impairment in learning, particularly generalization, while the GAD group demonstrated more pronounced deficits in visual memory.

LIMITATIONS

Patients involved were medicated and the sample size for GAD was relatively small.

CONCLUSIONS

The significant differences in visual memory and learning between MDD and GAD groups might be indicators to distinguishing both disorders. These results confirm that cognitive function is of great importance as a future target for treatment in order to improve wellbeing, quality of life and functionality in both GAD and MDD.

Massive visual long-term memory is largely dependent on meaning

Previous research demonstrated a massive capacity of visual long-term memory (VLTM) for meaningful images. However, the capacity and limits of a "pure" VLTM that is independent of conceptual information still need to be determined. In the encoding phase of three experiments, participants viewed hundreds of images depicting real-world objects, along with visually similar images that were stripped of their semantic meaning. VLTM was evaluated using a four-alternative-forced-choice test including old and new images and their counterpart mirror transformations. The results revealed superior memory for meaningful than for meaningless stimuli and importantly, there was no hint of a massive VLTM for the meaningless items. Furthermore, when examining memory recognition of visual properties per-se (i.e., original/mirror state), memory was overall poor, and practically negligible for the meaningless items. Taken together, our findings suggest that meaning is critical for massive VLTM and for the ability to store visual properties.

The pattern glare and visual memory are disrupted in patients with major depressive disorder

BACKGROUND

Visual memory impairment is one of the most commonly complained symptoms in patients with major depressive disorder (MDD). Pattern glare is also a distorted visual phenomenon that puzzles patients with MDD. Nevertheless, how these two phenomena interact in MDD remains unknown. This study investigated the association between pattern glare and visual memory in MDD patients.

METHODS

Sixty-two patients with MDD and forty-nine age-, sex- and education level-matched healthy controls (HCs) were included in this study. The Pattern Recognition Memory (PRM) test and the Brief Visual Memory Test-Revised (BVMT-R) were applied to measure visual memory. The pattern glare test including three patterns with different spatial frequencies (SFs) was used to explore pattern glare levels.

RESULTS

Patients with MDD scored lower on the PRM-PCi, BVMT-R1, BVMT-R2, BVMT-R3, and BVMT-Rt and higher on the PRM-MCLd than HCs (all p < 0.05). Pattern glare scores for MDD patients were higher with mid-SF (p < 0.001), high-SF (p = 0.006) and mid-high SF differences (p = 0.01) than for HCs. A positive correlation between mid-SF and PRM-MCLd scores in all participants was observed (p = 0.01, r = 0.246). A negative correlation between mid-high difference scores and BVMT-R2 scores (p = 0.032, r = -0.317) was observed in HCs, but no significant correlation was observed in MDD patients.

CONCLUSIONS

The present study showed that visual memory and pattern glare are disrupted in MDD. Visual memory may be associated with pattern glare and needs to be studied in future work.

Eye movements and eating disorders: protocol for an exploratory experimental study examining the relationship in young-adult women with subclinical symptomatology

BACKGROUND

Recent research indicates that patients with anorexia (AN) show specific eye movement abnormalities such as shorter prosaccade latencies, more saccade inhibition errors, and increased rate of saccadic intrusions compared to participants without AN. However, it remains unknown whether these abnormal eye movement patterns, which may serve as potential biomarkers and endophenotypes for an early diagnosis and preventive clinical treatments, start to manifest also in people with subclinical eating disorders (ED) symptomatology. Therefore, we propose a protocol for an exploratory experimental study to investigate whether participants with subclinical ED symptomatology and control participants differ in their performance on several eye movement tasks.

METHODS

The sample will be recruited through convenience sampling. The Eating Disorder Examination Questionnaire will be administered as a screening tool to split the sample into participants with subclinical ED symptomatology and control participants. A fixation task, prosaccade/antisaccade task, and memory-guided task will be administered to both groups. Additionally, we will measure anxiety and premorbid intelligence as confounding variables. Means comparison, exploratory Pearson's correlations and discriminant analysis will be performed.

DISCUSSION

This study will be the first to elucidate the presence of specific eye movement abnormalities in participants with subclinical ED symptomatology. The results may open opportunities for developing novel diagnostic tools/therapies being helpful to the EDs research community and allied fields.

False memories when viewing overlapping scenes

Humans can memorize and later recognize many objects and complex scenes. In this study, we prepared large photographs and presented participants with only partial views to test the fidelity of their memories. The unpresented parts of the photographs were used as a source of distractors with similar semantic and perceptual information. Additionally, we presented overlapping views to determine whether the second presentation provided a memory advantage for later recognition tests. Experiment 1 (N = 28) showed that while people were good at recognizing presented content and identifying new foils, they showed a remarkable level of uncertainty about foils selected from the unseen parts of presented photographs (false alarm, 59%). The recognition accuracy was higher for the parts that were shown twice, irrespective of whether the same identical photograph was viewed twice or whether two photographs with overlapping content were observed. In Experiment 2 (N = 28), the memorability of the large image was estimated by a pre-trained deep neural network. Neither the recognition accuracy for an image part nor the tendency for false alarms correlated with the memorability. Finally, in Experiment 3 (N = 21), we repeated the experiment while measuring eye movements. Fixations were biased toward the center of the original large photograph in the first presentation, and this bias was repeated during the second presentation in both identical and overlapping views. Altogether, our experiments show that people recognize parts of remembered photographs, but they find it difficult to reject foils from unseen parts, suggesting that their memory representation is not sufficiently detailed to rule them out as distractors.

Incidental visual memory and metamemory for a famous monument

In the context of urban life, some monuments are ecologically relevant landmarks for some people. However, previous research on the topic of incidental memory of everyday settings has relatively ignored how people remember monuments from their environments. The present work examined visual memory (i.e., recall and recognition) and metamemory for the Puerta de Alcalá (“Alcalá Gate” in English), a famous ornamental monument in the city of Madrid (Spain). Despite the monument’s perceptual simplicity, participants showed poor visual memory of it in a recall task (drawings), as only 16% of them correctly drew the monument; moreover, only 45% of the participants correctly recognized it in a four-alternative forced-choice test. In contrast, participants reported higher levels of confidence for both recall and recognition (51.57 ± 20.5 and 79.54 ± 19.6, respectively on a 100-point scale). Importantly, memory performance did not vary as a function of the number of years lived near the monument or of the self-reported contact frequency (familiarity) with the monument. The current findings have relevant implications in understanding the link between visual attention, memory, and metamemory in real-world settings.

Accelerated long-term forgetting in children with temporal lobe epilepsy: A timescale investigation of material specificity and executive skills

Recently, children with temporal lobe epilepsy (TLE) were found to be at risk of accelerated long-term forgetting (ALF). In this study, we examined the temporal trajectory of ALF, while exploring the relationship between ALF, executive skills, and epilepsy variables. Fifty-one children, (23 with TLE and 28 typically developing) completed a battery of neuropsychological tests of verbal and visual memory, executive skills, and two experimental memory tasks (verbal and visual) involving recall after short (30-min) and extended (1-day and 2-week) delays. Side of seizure focus and hippocampal integrity were considered. On the visual task (Scene Memory), children with TLE performed comparably to typically developing children following a 30-min and 1-day delay, although worse than typically developing children at 2 weeks: ALF was observed in children with right TLE focus. The two groups did not differ on the experimental verbal memory task. Children with TLE also had worse performance than typically developing children on standardized verbal memory test and on tests of executive skills (i.e., verbal generativity, inhibition, working memory, complex attention). Only complex attention was associated with visual ALF. ALF was present for visuo-spatial materials in children with TLE at two weeks, and children with right TLE were most susceptible. A relationship was identified between complex attention and long-term forgetting. The findings extend our understanding of difficulties in long-term memory formation experienced by children with TLE.

Neurocognitive features, personality traits, and social function in patients with schizophrenia with a history of violence

Recent literature examining associations between cognitive function, clinical features, and violence in patients with schizophrenia has been growing; however, the results are inconsistent. Reports on social function and personality are limited. These studies are yet to be reflected in risk assessment tools and management plans. The aim of this study is to provide a resource for risk assessment and intervention studies by conducting multifaceted well-established assessments in a large population. Data from 355 patients with schizophrenia (112 patients with a history of violence; 243 patients without a history of violence) and 1265 healthy subjects were extracted from a large database of individuals with mental disorders in a general psychiatric population in Japan. The associations between violence in patients with schizophrenia and intellectual function, cognitive function (memory function, executive function, attentional function, verbal learning, processing speed, social cognition), clinical variables, personality traits, social function, and quality of life (QOL) were analyzed. Compared with healthy subjects, the schizophrenia group had broadly impaired cognitive function and social cognition, and their personality traits showed similar differences as those reported previously. Patients with schizophrenia with a history of violence showed significantly more impaired visual memory function (P = 1.9 × 10^-5, Cohen's d = 0.34), longer hospitalization (P = 5.9 × 10^-4, Cohen's d = 0.38), more severe excited factor on Positive and Negative Syndrome Scale (P = 1.6 × 10^-4, Cohen's d = 0.47), higher self-transcendence personality construct on the Temperament and Character Inventory (P = 1.8 × 10^-4, Cohen's d = 0.46), and shorter total working hours per week (P = 4.8 × 10^-4, Cohen's d = 0.53) than those with schizophrenia without a history of violence. New findings, including impaired visual memory, a high self-transcendence personality trait, and shorter total working hours, could be focused on in future interventional research.

Differential associations of visual memory with hippocampal subfields in subjective cognitive decline and amnestic mild cognitive impairment

Background

Although previous studies have demonstrated that the hippocampus plays a role in verbal memory, the role of hippocampal subfields in visual memory is uncertain, especially in those with preclinical Alzheimer's disease (AD). This study aimed to examine relationships between hippocampal subfield volumes and visual memory in SCD (subjective cognitive decline) and aMCI (amnestic mild cognitive impairment).

Methods

The study sample included 47 SCD patients, 62 aMCI patients, and 51 normal controls (NCs) and was recruited from Shanghai Jiao Tong University Affiliated Sixth People's Hospital. Visual memory was measured by the subtests of BVMT-R (Brief Visuospatial Memory Test-Revised), PLT (Pictorial Learning Test), DMS (Delayed Matching to Sample), and PAL (Paired Associates Learning). Hippocampal subfield volumes were estimated using FreeSurfer software (version 6.0). We modeled the association between visual memory and relative hippocampal subfield volumes (dividing by estimated total intracranial volume) using Pearson's correlation and linear regression.

Results

Compared with the NC group, patients with SCD did not find any relative hippocampal subregion atrophy, and the aMCI group found atrophy in CA1, molecular layer, subiculum, GC-ML-DG, CA4, and CA3. After adjusting for covariates (age, sex, and APOE ε4 status) and FDR (false discovery rate) correction of p (q values) < 0.05, in NC group, DMS delay matching scores were significant and negatively associated with presubiculum (r = -0.399, FDR q = 0.024); in SCD group, DMS delay matching scores were negatively associated with CA3 (r = -0.378, FDR q = 0.048); in the aMCI group, BVMT-R immediate recall scores were positively associated with CA1, molecular layer, subiculum, and GC-ML-DG (r = 0.360–0.374, FDR q < 0.036). Stepwise linear regression analysis confirmed the association.

Conclusions

Our results indicate a different and specific correction of visual memory with relative hippocampal subfield volumes between SCD and aMCI. The correlations involved different and more subfields as cognitive decline. Whether these associations predict future disease progression needs dynamic longitudinal studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02853-7.

The modified Ruche visuospatial learning test (RUCHE-M) for the assessment of visuospatial episodic memory in patients with temporal lobe epilepsy: Preliminary evidence for the investigation of memory binding

INTRODUCTION

The Ruche test is a visuospatial form of the Rey auditory verbal learning test (RAVLT), with initial evidence of utility in the diagnosis of temporal lobe epilepsy (TLE)-related memory disorders.

AIMS

To present the translation to Brazilian Portuguese and modification of the Ruche test (RUCHE-M) and compare the RUCHE-M and RAVLT performance between patients with right and left TLE.

METHODS

Twenty-five neuropsychologists participated in instrument adaptation. Thirty-seven patients with right (n = 19) and left (n = 18) TLE participated. Data were compared with the Mann-Whitney U test.

RESULTS

All specialists considered the final RUCHE-M to be adequate. The RUCHE-M forgetting speed index (FSI) score and several RAVLT scores differed significantly between patients with right and left TLE.

CONCLUSION

The RUCHE-M showed limited utility for the assessment of visuospatial episodic memory in patients with TLE. The manipulation of memory binding as demonstrated by FSI score seems to be a promising paradigm for the assessment of right hippocampal function.

Subjective cognitive complaints and objective cognitive impairment in hoarding disorder

Individuals with Hoarding Disorder (HD) frequently complain of problems with attention and memory. These self-identified difficulties are often used as justification for saving and acquiring behaviors. Research using neuropsychological measures to examine verbal and visual memory performance and sustained attention have reported contradictory findings. Here we aim to determine the relationship between self-reported problems with memory and attention, objective memory and attention performance, and self-reported depression and anxiety symptoms in HD. Data was available for 319 individuals who participated in a treatment study of HD. Multiple regression was used to assess the relationship between self-reported complaints and objective measures, with age, education, and measures of depression and anxiety included as covariates. We found no association between self-reported memory difficulties and objective verbal or visual memory performance. Self-reported problems with attention were associated with objective attentional performance, although this relationship was partially accounted for by anxiety symptom severity. There was a small association between visual memory performance at baseline and improvements in hoardingrelated functional abilities following treatment. Improvements in subjective memory complaints pre-to-post treatment were associated with improvements in hoarding symptom severity and hoarding-related functioning. These results demonstrate a dissociation between perceived and objective functioning in HD.

Memory after visual search: Overlapping phonology, shared meaning, and bilingual experience influence what we remember

How we remember the things that we see can be shaped by our prior experiences. Here, we examine how linguistic and sensory experiences interact to influence visual memory. Objects in a visual search that shared phonology (cat-cast) or semantics (dog-fox) with a target were later remembered better than unrelated items. Phonological overlap had a greater influence on memory when targets were cued by spoken words, while semantic overlap had a greater effect when targets were cued by characteristic sounds. The influence of overlap on memory varied as a function of individual differences in language experience -- greater bilingual experience was associated with decreased impact of overlap on memory. We conclude that phonological and semantic features of objects influence memory differently depending on individual differences in language experience, guiding not only what we initially look at, but also what we later remember.

Standardization and normative data for a new test of visual long-term recognition memory

The assessment of recognition memory is useful in several neurological conditions, but normative data for visual recognition memory of complex figures are still missing for the Italian population. The aim of this study is to present a new short test of visual recognition memory that consists in a supplementary task to be administered after the free delayed recall trial of the Modified Taylor Complex Figure (MTCF). The MTCF-Recognition Trial (MTCF-RT) includes 10 tables, each with a sub-component of the MTCF coupled with two interfering stimuli. Participants are asked to point, for each triplet, the item that was part of the original picture. Normative data were collected from a sample of 280 healthy Italian native speakers ranging in age from 18 to 89 years. The mean recognition score on the MTCF-RT was 9.125 ± 0.996. Results from multiple regression analyses showed that age and education (but not gender) were significant predictors of performance. Therefore, we provided correction grids to adjust raw scores for age and education and computed equivalent scores for the use of the MTCF-RT in the clinical assessment of recognition memory.

Medium strength visual long-term memories are the most fragile

What memories do humans forget? One theory proposes that memories stored with moderate activation levels are weakened when faced with competitive stress so that they are particularly prone to be forgotten. However, research suggests that visual long-term memories are stronger than memories of other modalities, and therefore may never fall into this moderate activation zone. Here we tested these competing predictions by showing to-be-remembered pictures while we recorded event-related potentials (ERPs) indexing memory activation during encoding. We found that visual memories with medium levels of activation when first encoded were more prone to forgetting than memories with high or low encoding activation levels, but this only occurred if a memory was faced with competition. This study shows that we forget moderately activated memories when they are subjected to competition, regardless of the modality of experience.

Association Between Visual Memory and In Vivo Amyloid and Tau Pathology in Preclinical Autosomal Dominant Alzheimer's Disease

OBJECTIVE

Visual memory (ViM) declines early in Alzheimer's disease (AD). However, it is unclear whether ViM impairment is evident in the preclinical stage and relates to markers of AD pathology. We examined the relationship between ViM performance and in vivo markers of brain pathology in individuals with autosomal dominant AD (ADAD).

METHODS

Forty-five cognitively unimpaired individuals from a Colombian kindred with the Presenilin 1 (PSEN1) E280A ADAD mutation (19 carriers and 26 noncarriers) completed the Rey-Osterrieth Complex Figure immediate recall test, a measure of ViM. Cortical amyloid burden and regional tau deposition in the entorhinal cortex (EC) and inferior temporal cortex (IT) were measured using 11C-Pittsburgh compound B positron emission tomography (PET) and 11F-flortaucipir PET, respectively.

RESULTS

Cognitively unimpaired carriers and noncarriers did not differ on ViM performance. Compared to noncarriers, carriers had higher levels of cortical amyloid and regional tau in both the EC and IT. In cognitively unimpaired carriers, greater cortical amyloid burden, higher levels of regional tau, and greater age were associated with worse ViM performance. Only a moderate correlation between regional tau and ViM performance remained after adjusting for verbal memory scores. None of these correlations were observed in noncarriers.

CONCLUSIONS

Results suggest that AD pathology and greater age are associated with worse ViM performance in ADAD before the onset of clinical symptoms. Further investigation with larger samples and longitudinal follow-up is needed to examine the utility of ViM measures for identifying individuals at high risk of developing dementia later in life.

Prosopagnosia and disorders of face processing

Face recognition is a form of expert visual processing. Acquired prosopagnosia is the loss of familiarity for facial identity and has several functional variants, namely apperceptive, amnestic, and associative forms. Acquired forms are usually caused by either occipitotemporal or anterior temporal lesions, right or bilateral in most cases. In addition, there is a developmental form, whose functional and structural origins are still being elucidated. Despite their difficulties with recognizing faces, some of these subjects still show signs of covert recognition, which may have a number of explanations. Other aspects of face perception can be spared in prosopagnosic subjects. Patients with other types of face processing difficulties have been described, including impaired expression processing, impaired lip-reading, false familiarity for faces, and a people-specific amnesia. Recent rehabilitative studies have shown some modest ability to improve face perception in prosopagnosic subjects through perceptual training protocols.

A motion compensation treadmill for untethered wood ants (Formica rufa): evidence for transfer of orientation memories from free-walking training

The natural scale of insect navigation during foraging makes it challenging to study under controlled conditions. Virtual reality and trackball setups have offered experimental control over visual environments while studying tethered insects, but potential limitations and confounds introduced by tethering motivates the development of alternative untethered solutions. In this paper, we validate the use of a motion compensator (or ‘treadmill’) to study visually driven behaviour of freely moving wood ants (Formica rufa). We show how this setup allows naturalistic walking behaviour and preserves foraging motivation over long time frames. Furthermore, we show that ants are able to transfer associative and navigational memories from classical maze and arena contexts to our treadmill. Thus, we demonstrate the possibility to study navigational behaviour over ecologically relevant durations (and virtual distances) in precisely controlled environments, bridging the gap between natural and highly controlled laboratory experiments.

Summary: We have developed and validated a motion compensating treadmill for wood ants which opens new perspectives to study insect navigation behaviour in a fully controlled manner over ecologically relevant durations.

The Effect of Language-Specific Characteristics on English and Japanese Speakers' Ability to Recall Number Information

The current paper presents two experiments investigating the effect of presence versus absence of compulsory number marking in a native language on a speaker's ability to recall number information from photos. In Experiment 1, monolingual English and Japanese adults were shown a sequence of 110 photos after which they were asked questions about the photos. We found that the English participants showed a significantly higher accuracy rate for questions testing recall for number information when the correct answer was "2" (instead of "1") than Japanese participants. In Experiment 2, English and Japanese adults engaged in the same task as in Experiment 1 with an addition that explored reasons for the results found in Experiment 1. The results of Experiment 2 were in line with the results of Experiment 1, but also suggested that the results could not be attributed to differences in guessing patterns between the two groups or the type of linguistic constructions used in the test situations. The current study suggests that native language affects speakers' ability to recall number information from scenes and thus provides evidence for the Whorfian hypothesis.

Working memory limits severely constrain long-term retention

There has been considerable controversy in recent years as to whether information held in working memory (WM) is rapidly forgotten or automatically transferred to long-term memory (LTM). Although visual WM capacity is very limited, we appear able to store a virtually infinite amount of information in visual LTM. Still, LTM retrieval often fails. Some view visual WM as a mental sketchpad that is wiped clean when new information enters, but not a consistent precursor of LTM. Others view the WM and LTM systems as inherently linked. Distinguishing between these possibilities has been difficult, as attempts to directly manipulate the active holding of information in visual WM has typically introduced various confounds. Here, we capitalized on the WM system's capacity limitation to control the likelihood that visual information was actively held in WM. Our young-adult participants (N = 103) performed a WM task with unique everyday items, presented in groups of two, four, six, or eight items. Presentation time was adjusted according to the number of items. Subsequently, we tested participants' LTM for items from the WM task. LTM was better for items presented originally within smaller WM set sizes, indicating that WM limitations contribute to subsequent LTM failures, and that holding items in WM enhances LTM encoding. Our results suggest that a limit in WM capacity contributes to an LTM encoding bottleneck for trial-unique familiar objects, with a relatively large effect size.

Implicit outcomes expectancies shape memory process: Electrophysiological evidence

The simple manipulation of pairing specific outcomes with the sample stimuli strongly affects discriminative learning and memory processes. This procedure has been named the Differential Outcomes Procedure (DOP) and is usually compared to a control condition (the non-differential procedure, NOP) consisting in the random administration of the outcomes after each correct response. Recent research has revealed that the DOP effect arises even under unconscious conditions. In this study, we explored the temporal dynamics of short-term memory processes in both the DOP and the NOP in the absence of awareness of either the outcome (Experiment 1A) or the initial sample stimulus (Experiment 1B) through the evoked-related potentials technique. Results showed distinctive electrophysiological activation patterns in the DOP compared with the NOP at encoding, maintenance and retrieval phases. The present findings provide electrophysiological evidence of implicit-prospective processes involved in the DOP. They elucidate the processes that result in improved visual recognition memory.

Direct brain recordings reveal occipital cortex involvement in memory development

Processing of low-level visual information shows robust developmental gains through childhood and adolescence. However, it is unknown whether low-level visual processing in the occipital cortex supports age-related gains in memory for complex visual stimuli. Here, we examined occipital alpha activity during visual scene encoding in 24 children and adolescents, aged 6.2-20.5 years, who performed a subsequent memory task while undergoing electrocorticographic recording. Scenes were classified as high- or low-complexity by the number of unique object categories depicted. We found that recognition of high-complexity, but not low-complexity, scenes increased with age. Age was associated with decreased alpha power and increased instantaneous alpha frequency during the encoding of subsequently recognized high- compared to low-complexity scenes. Critically, decreased alpha power predicted improved recognition of high-complexity scenes in adolescents. These findings demonstrate how the functional maturation of the occipital cortex supports the development of memory for complex visual scenes.

False memories for scenes using the DRM paradigm

People are remarkably good at remembering photographs. To further investigate the nature of the stored representations and the fidelity of human memories, it would be useful to evaluate the visual similarity of stimuli presented in experiments. Here, we explored the possible use of convolutional neural networks (CNN) as a measure of perceptual or representational similarity of visual scenes with respect to visual memory research. In Experiment 1, we presented participants with sets of nine images from the same scene category and tested whether they were able to detect the most distant scene in the image space defined by CNN. Experiment 2 was a visual variant of the Deese-Roediger-McDermott paradigm. We asked participants to remember a set of photographs from the same scene category. The photographs were preselected based on their distance to a particular visual prototype (defined as centroid of the image space). In the recognition test, we observed higher false alarm rates for scenes closer to this visual prototype. Our findings show that the similarity measured by CNN is reflected in human behavior: people can detect odd-one-out scenes or be lured to false alarms with similar stimuli. This method can be used for further studies regarding visual memory for complex scenes.

Intraindividual relative deficits in visual memory to lateralize seizure onset in temporal lobe epilepsy

It is well established that presurgical neuropsychological assessment can assist in lateralizing and localizing focal epileptogenic regions. However, unlike verbal memory impairment, which is a robust and reliable finding in patients with left temporal lobe epilepsy (LTLE), nonverbal memory deficits are less consistently found among patients with right TLE (RTLE). This study aimed to determine whether memory assessment for spatial location in addition to visual content would differentiate patients with RTLE and LTLE. We compared performances between patients with 25 RTLE and 37 patients with LTLE on the Wechsler Advanced Clinical Solutions-Faces (ACS-F) subscales (Faces I, Faces II, Content, and Spatial), verbal-visual memory asymmetry scores, and intelligence quotient (IQ)-visual memory difference scores. Results revealed no significant differences between patients with RTLE and LTLE for any ACS-F memory score. By contrast, groups demonstrated significant differences in memory asymmetry scores (p = .007) and IQ difference scores (p = .006). Thus, visual memory scores in isolation failed to differentiate groups with RTLE and LTLE; however, within-patient differences between visual memory and other cognitive abilities successfully differentiated the groups. These results highlight the importance of using an intraindividual model of neuropsychological assessment to identify relative weaknesses potentially associated with the epileptogenic region.

Orally Administered Cinnamon Extract Attenuates Cognitive and Neuronal Deficits Following Traumatic Brain Injury

The present paper shows how cinnamon extract (CE) consumption mitigates neuronal loss and memory impairment following traumatic brain injury (TBI), one of the world's most common neurodegenerative diseases. TBI patients suffer short- and long-term behavioral, cognitive, and emotional impairments, including difficulties in concentration, memory loss, and depression. Research shows that CE application can mitigate cognitive and behavioral impairments in animal models for Alzheimer's and Parkinson's disease, whose pathophysiology is similar to that of TBI. This study builds on prior research by showing similar results in TBI mice models. After drinking CE for a week, mice were injured using our 70-g weight drop TBI device. For 2 weeks thereafter, the mice continued drinking CE alongside standard lab nutrition. Subsequently, the mice underwent behavioral tests to assess their memory, motor activity, and anxiety. The mice brains were harvested for immunohistochemistry staining to evaluate overall neuronal survival. Our results show that CE consumption almost completely mitigates memory impairment and decreases neuronal loss after TBI. Mice that did not consume CE demonstrated impaired memory. Our results also show that CE consumption attenuated neuronal loss in the temporal cortex and the dentate gyrus. Mice that did not consume CE suffered a significant neuronal loss. There were no significant differences in anxiety levels and motor activity between all groups. These findings show a new therapeutic approach to improve cognitive function and decrease memory loss after TBI.

Oral administration of porcine liver decomposition product for 4 weeks enhances visual memory and delayed recall in healthy adults over 40 years of age: A randomized, double-blind, placebo-controlled study

BACKGROUND AND OBJECTIVES

Porcine liver decomposition product (PLDP) contains neurofunctional phospholipids. We previously reported that PLDP enhances cognitive function in healthy adult humans, based on clinical evaluations using Hasegawa's Dementia Scale-Revised. In this study, we evaluated the effect of PLDP on memory indicators of the Wechsler Memory Scale-Revised (WMS-R), an internationally recognized battery for memory assessment.

METHODS

We conducted a double-blind parallel-group placebo-controlled trial to evaluate the effect of PLDP on memory. Fifty-eight participants competed the trial: 28 participants were in the PLDP group and 30 participants were in the placebo group. Each group was administered PLDP (4 capsules) or a placebo (4 capsules) for 4 continuous weeks. WMS-R was administered before and 4 weeks after PLDP or placebo intake. The data were also subdivided by age for participants under 40 years (N = 15 in PLDP; N = 15 in placebo) and over 40 years (N = 13 in PLDP, N = 15 in placebo). Changes in Verbal Memory, Visual Memory, Attention/Concentration, and Delayed Recall were analyzed.

RESULTS

No significant differences were found in any memory indicators between the PLDP group and the placebo group in pooled participants and in participants under 40 years of age. However, for participants over 40 years of age, PLDP administration resulted in a significant enhancement than placebo administration in Delayed Recall (14.1 ± 7.1 points vs. 7.1 ± 6.8 points) (P < 0.05), Visual Recall I (20.1 ± 23.1 percentile vs 1.9 ± 22.8 percentile) (P < 0.05), and Visual Recall II (24.2 ± 25.8 percentile vs 6.7 ± 19.0 percentile) (P < 0.05), respectively. The composition ratio of men to women in each group was imbalanced but no significant difference existed between the two groups.

LIMITATIONS

A modest sample size, single-center design, and a fairly short follow-up period.

CONCLUSION

PLDP enhanced Visual Memory and Delayed Recall in healthy adults over 40 years of age but not in healthy adults under 40 years of age. Therefore, PLDP may represent a promising nutraceutical that could improve cognitive function in healthy adults over 40 years of age. Further studies are required to evaluate if long term PLDP administration can prevent or delay cognitive dysfunction in healthy adults over 40 years of age.

Impaired memory for temporal context in schizophrenia patients with hallucinations and thought disorganisation

INTRODUCTION

Context processing deficiencies have been established in patients with schizophrenia and it has been proposed that these deficiencies are involved in the formation of positive symptoms.

METHOD

We administered a temporal context discrimination task to 60 schizophrenia patients and 60 healthy individuals. Pictures were presented in two sessions separated by half an hour and the participants were required to remember afterwards whether the pictures had been presented in the first or the second session.

RESULTS

The number of temporal context errors was significantly increased in the patient group. More specifically, it was highly significantly increased in a subgroup of patients presenting hallucinations, while the patients without hallucinations were equivalent to the healthy individuals. Regression analyses revealed that, independently of memory of the pictures themselves, verbal and visual hallucinations, as well as thought disorganisation, were associated with more temporal context errors. In contrast, affective flattening and anhedonia were associated with fewer of these errors.

CONCLUSION

Inability to process or remember the temporal context of production of events might be a mechanism underlying both hallucinations and thought disorganisation.

Novelty exposure modulates visual and verbal emotional memory: An experimental design with adults

The detection and processing of novelty play a critical role in memory formation. The effect of novelty intervention in memory has been demonstrated with rodents in several lines of research; however, it has not been explored as extensively in humans. In this research, we evaluated the effect of novelty exposure on two types of emotional memory: visual (Study 1) and verbal (Study 2). Eighty healthy volunteers participated in both studies. First, all participants watched a video (session 1); seven days later (session 2), participants in the control group watched the same video and those in the experimental condition were exposed to a novel one. Immediately after exposure, all participants looked at 36 pictures (or listened to 36 words). Soon afterward, a two-task test was administered to evaluate memory (immediate free recall and recognition). A week later (session 3), the two-task test was run again (deferred free recall and recognition). Regarding emotional memory processing, the emotional information was more activating and better remembered than the neutral one, for both visual and verbal information. Regarding the novelty effect, the participants exposed to the novel video had better recall than the control on the deferred measures. Thus, our results provide evidence of the effect of novelty exposure on two different types of emotional memory, with great potentialities in clinical and educational settings.

Tell me what you saw: The usefulness of verbal descriptions for others

Describing what one saw to another person is common in everyday experience, such as spatial navigation and crime investigations. Past studies have examined the effects of recounting on one's own memory, neglecting an important function of memory recall in social communication. Here we report surprisingly low utility of one's verbal descriptions for others, even when visual memory for the stimuli has high capacity. Participants described photographs of common objects they had seen to enable judges to identify the target object from a foil in the same basic-level category. When describing from perception, participants were able to provide useful descriptions, allowing judges to accurately identify the target objects 87% of the time. Judges' accuracy decreased to just 57% when participants provided descriptions from memory acquired minutes ago, and to near chance (51.8%) when the verbal descriptions were based on memory acquired 24 hours ago. Comparison of participants' own identification accuracy with judges' accuracy suggests the presence of a common source of errors. This finding suggests that recall and recognition of visual objects share common memory sources. In addition, the low utility of one's verbal descriptions constrains theories about the extension of one's memory to the external world and has implications for eyewitness identification and laws governing it.

Depressive symptoms as predictors of visual memory deficits in middle-age

BACKGROUND

Depression has been known to affect memory and other cognitive domains. The objective of this longitudinal cohort study was to investigate longitudinal associations between depressive symptoms at age 31 years and visual memory and new learning at the age of 46 years. We investigated whether depressive symptoms at age 31 predicted visual memory deficits at age 46 years, and whether changes in depressive symptoms between 31 and 46 years predicted visual memory at age 46.

METHODS

Participants were members of the Northern Finland Birth Cohort 1966. Depressive symptoms were assessed with the Symptom Checklist-25 (SCL-25) on both occasions. Visual memory and new learning were assessed using Paired Associative Learning (PAL) test at the age 46 follow-up. PAL total errors adjusted and first trial memory score were used as outcomes and basic educational level, relationship status, physical activity and diet at baseline were considered as confounding factors in linear regression analysis.

RESULTS

A total of 5029 (57% female) participants were included in the main analysis. No associations were found between depressive symptoms or change in depressive symptoms and visual memory and new learning scores. The result did not change following cut-offs 1.55 and 1.75 for depression.

LIMITATIONS

SCL-25 only measures symptoms during the past week. Only one cognitive domain was assessed.

CONCLUSIONS

Contrary to our hypothesis, neither baseline depressive symptoms nor change in depressive symptoms predicted visual memory scores 15 years later. It appears that sub-clinical depressive symptoms do not effect this cognitive domain in the middle-aged population.

Context effects on reproduced magnitudes from short-term and long-term memory

Extant research has demonstrated strong contextual dependencies in reproducing magnitudes of perceptual stimuli from short-term memory. Two experiments examined how context as defined by (a) the mean of the distribution, (b) stimulus ranks, (c) values of anchor stimuli used in the reproduction task, and (d) values from the most recent trial operate on estimates of square size. Experiment 1 demonstrated distributional contrast effects on ratings of squares and distributional assimilation effects on reproduction of squares from short-term memory for the same participants. The fit of a modified version of the category adjustment model demonstrated reliable effects of the running mean, start anchors, and previous stimulus on reproduction bias. In Experiment 2, participants first learned to associate labels with squares, then reproduced square sizes based on the label cues, a long-term memory task, followed by a reproduction from short-term memory task as in Experiment 1. Results for the short-term memory task were largely consistent with Experiment 1. Results for the long-term memory task showed a very different pattern of effects, with larger reproduced sizes when squares were drawn from positively skewed rather than negatively skewed distributions. This contrast effect was explained by a modified range-frequency model as the result of rank encoding of square values along with displacement away from the running mean and shifts towards the prior response and start anchors. The combined results identify multiple sources of context effects in estimation that depend critically on memory retrieval factors and show how they can be incorporated into existing models.

The visual nonverbal memory trace is fragile when actively maintained, but endures passively for tens of seconds

Despite attempts at active maintenance in the focus of attention, the fragile nature of the visual nonverbal memory trace may be revealed when the retention interval between target memoranda and probed recall on a trial is extended. In contrast, a passively maintained or unattended visual memory trace may be revealed as persisting proactive interference extending across quite extended intervals between trials in a recent probes task. The present study, comprising five experiments, used this task to explore the persistence of such a passive visual memory trace over time. Participants viewed some target visual items (for example, abstract colored patterns) followed by a variable retention interval and a probe item. The task was to report whether the probe matched one of the targets or not. A decaying active memory trace was indicated by poorer performance as the memory retention interval was extended on a trial. However, when the probe was a member of the target set from the preceding trial, task performance was poorer than a comparison novel probe, demonstrating proactive interference. Manipulations of the intertrial interval revealed that the temporal persistence of the passive memory trace of an old target was impressive, and proactive interference was largely resilient to a simple ‘cued forgetting’ manipulation. These data support the proposed two-process memory conception (active–passive memory) contrasting fragile active memory traces decaying over a few seconds with robust passive traces extending to tens of seconds.

MemCat: a new category-based image set quantified on memorability

Images differ in their memorability in consistent ways across observers. What makes an image memorable is not fully understood to date. Most of the current insight is in terms of high-level semantic aspects, related to the content. However, research still shows consistent differences within semantic categories, suggesting a role for factors at other levels of processing in the visual hierarchy. To aid investigations into this role as well as contributions to the understanding of image memorability more generally, we present MemCat. MemCat is a category-based image set, consisting of 10K images representing five broader, memorability-relevant categories (animal, food, landscape, sports, and vehicle) and further divided into subcategories (e.g., bear). They were sampled from existing source image sets that offer bounding box annotations or more detailed segmentation masks. We collected memorability scores for all 10 K images, each score based on the responses of on average 99 participants in a repeat-detection memory task. Replicating previous research, the collected memorability scores show high levels of consistency across observers. Currently, MemCat is the second largest memorability image set and the largest offering a category-based structure. MemCat can be used to study the factors underlying the variability in image memorability, including the variability within semantic categories. In addition, it offers a new benchmark dataset for the automatic prediction of memorability scores (e.g., with convolutional neural networks). Finally, MemCat allows the study of neural and behavioral correlates of memorability while controlling for semantic category.

The fidelity of visual and auditory memory

Recent studies show that recognition memory for pictures is consistently better than recognition memory for sounds. The purpose of this experiment was to compare the fidelity of auditory and visual memory to better understand the reported differences in the two memory systems. Participants received a study phase with pictures/sounds, followed by a same-day memory test or a delayed recognition memory test. During the memory test, participants were presented with pictures/sounds that were old (presented during study), novel foils not presented during study, or exemplar foils that were variants of objects presented during study. Participants were instructed to classify each picture/sound as "old" or "new" by pressing a corresponding key. The same-day memory task revealed fundamental differences in visual and auditory memory: auditory representations are coarse and gist-based, while visual representations are highly detailed. However, auditory and visual memory performance was similar after a delay of 2 and 7 days and both types of memory representations were more coarse and gist-based. The results make an important contribution to our understanding of how the world is represented in auditory and visual memory.

Altered neural correlates of episodic memory in adolescents with severe obesity

Negative effects of obesity on memory and associated medial temporal circuitry have been noted in animal models, but the status in humans, particularly children, is not well established. Our study is the first to examine neural correlates of successful memory encoding of visual scenes and their associated context in adolescents with severe obesity (age 14-18 years, 43% male). Despite similar subsequent memory as adolescents without obesity (BMI for age and sex <95th percentile), those with severe obesity (BMI for age and sex 120% above the 95th percentile) showed reduced hippocampal, parahippocampal, frontal, and parietal engagement during encoding of remembered visual scenes and greater lateral temporal engagement during encoding of their associated context. Standardized testing revealed a trend level group difference in memory performance, with a larger magnitude of obesity-related difference in recollection-related memory that was mediated by individual differences in lateral temporal activation during contextual encoding. The observed widespread functional alterations are concerning in light of the importance of mnemonic processing for academic achievement and feeding behavior and underscore the need for prevention and intervention initiatives for pediatric obesity.

Evidence from a 5-year follow-up Valencia study

BACKGROUND

Scarce research has focused on Visual Memory (VM) deficits as a possible neurocognitive endophenotype of bipolar disorder (BD). The main aim of this longitudinal, family study with healthy controls was to explore whether VM dysfunction represents a neurocognitive endophenotype of BD.

METHODS

Assessment of VM by Rey-Osterrieth Complex Figure Test (ROCF) was carried out on a sample of 317 subjects, including 140 patients with BD, 60 unaffected first-degree relatives (BD-Rel), and 117 genetically-unrelated healthy controls (HC), on three occasions over a 5-year period (T1, T2, and T3). BD-Rel group scores were analyzed only at T1 and T2.

RESULTS

Performance of BD patients was significantly worse than the HC group (p < 0.01). Performance of BD-Rel was also significantly different from HC scores at T1 (p < 0.01) and T2 (p = 0.05), and showed an intermediate profile between the BD and HC groups. Only among BD patients, there were significant differences according to sex, with females performing worse than males (p = 0.03). Regarding other variables, education represented significant differences only in average scores of BD-Rel group (p = 0.01).

LIMITATIONS

Important attrition in BD-Rel group over time was detected, which precluded analysis at T3.

CONCLUSIONS

BD patients show significant deficits in VM that remain stable over time, even after controlling sociodemographic and clinical variables. Unaffected relatives also show stable deficits in VM. Accordingly, the deficit in VM could be considered a potential endophenotype of BD, which in turn may be useful as a predictor of the evolution of the disease. Further studies are needed to confirm these findings.

Visual and verbal learning and memory in cystinosis

Cystinosis is a rare genetic lysosomal storage disorder characterized by the accumulation of cystine in lysosomes. Many organ systems are vulnerable to this cystine accumulation including the CNS. A past study demonstrated that children with cystinosis have deficits in visual learning and memory while their verbal learning and memory and global intellectual function are spared (Spilkin, Ballantyne, & Trauner, 2009). However, no related study has been performed to assess the dissociation between visual and verbal learning and memory in adults with cystinosis who have had the benefit of longterm treatment with the cystine-depleting agent, cysteamine. In this study we assessed visual and verbal learning and memory in 15 adults with cystinosis, with a mean age of 30.2 years. The results indicate that adults with cystinosis have no significant deficits in either verbal or visual learning and memory. However, the individuals did perform better on the verbal assessment. The results suggest that if early and continued treatment is given to individuals with cystinosis there is a relative sparing of visual learning and memory that might have otherwise declined. This emphasizes the essential nature of the proper clinical management of cystinosis.

How visual memory changes with intervening recall

Being asked to recount a visual memory is common in educational settings, spatial navigation, and crime investigation. Previous studies show that recounting one's memory can benefit subsequent memory, but most of this work either used verbal materials or conflated category memory with memory for visual details. To test whether recounting may introduce visually-specific interference effects, we tested people's memory for photographs of objects, but introduced an intervening phase in which people described their memory. We separated memory for the specific exemplar from memory for the basic-level category. Contrary to recent findings on maps and colours, the intervening retrieval practice did not consistently strengthen exemplar memory of objects. Instead, recounting one's visual memory appeared to introduce interference that sometimes cancelled the benefit of increased retrieval effort. Delaying the final memory test by 24 hr increased the benefit of retrieval practice. These findings suggest that intervening retrieval has multiple effects on visual memory. Instead of being a snapshot, this memory constantly changes with retrieval practice and with time.

Visual perception, visual-spatial cognition and mathematics: Associations and predictions in children with cerebral palsy

BACKGROUND

Previous research suggests that children with cerebral palsy (CP) have impairments in visual-spatial and mathematics abilities, although we know very little about the association between these two domains.

AIMS

To investigate the extent of visual-spatial and mathematical impairments in children with CP and the associations between these two domains.

METHOD AND PROCEDURE

Thirty-two children with predominantly quadriplegic spastic and/or athetoid (dyskinetic) CP (13 years 7 months) and a group of typically developing (TD) children (8 years 6 months) matched by receptive vocabulary were given a battery of visual-spatial and mathematics tasks. Visual-spatial assessments ranged from simple tests of perception to complex reasoning about these stimuli. A standardised test of mathematics ability was administered to both groups.

OUTCOMES AND RESULTS

The children with CP had significantly poorer mathematical and visual-spatial abilities than the TD group. For the TD group age was the best predictor of mathematical ability, in the CP group receptive vocabulary and visual perception abilities were the best predictors of mathematical ability.

CONCLUSION AND IMPLICATIONS

The CP group had extensive difficulties with visual perception; visual short-term memory; visual reasoning; and mental rotation all of which were associated with their mathematical abilities. These findings have implications for the teaching of visual perception and visual memory skills in young children with CP as these may help the development of mathematical abilities.

Sex-related variation of neurocognitive functioning in bipolar disorder: Focus on visual memory and associative learning

Bipolar disorder (BD) is associated with cognitive deficits in attention, verbal memory and executive functions. However, only few studies have examined sex effects on cognition despite their clinical relevance. Given that visual memory/ learning has been understudied the aim of our study was to investigate sex-related variation in cognition (executive functions and visual memory/ learning) in BD. Cognitive performance of 60 bipolar-I patients and 30 healthy controls was evaluated by using CANTAB battery tasks targeting spatial memory (SRM), paired associative learning (PAL) and executive functions. We fitted a multivariate analysis of covariance (MANCOVA), followed by task-specific ANCOVAs. A significant diagnosis by sex interaction effect was detected (MANCOVA); specifically, diagnosis-specific sex effects were found for SRM and PAL, as healthy males outperformed healthy females but this pattern was attenuated in BD patients. Patients' clinicodemographic characteristics, current psychopathology or medication status did not differ across sexes and were, therefore, unlikely to explain detected sex effects. Our study is one of few studies to assess sex-related variation in cognition in BD and the first to record a diagnosis-specific sex effect for two tasks of visuo-spatial memory/ learning, indicating that sex-related variation in healthy subjects is disrupted in BD.