Memory Test Research Articles

High-density lipoprotein over midlife and future cognition in women: The SWAN HDL ancillary study.

Limited data provides evidence-based insights on the association between comprehensive metrics of high-density lipoproteins (HDL) and cognitive performance, especially in midlife women for whom benefit might be the greatest. To assess the associations of serum HDL metrics including HDL lipid content [HDL cholesterol, phospholipid (HDL-PL), triglyceride], proteins/subclasses [apolipoprotein A-1 (apoA-1); small, medium, large, total HDL particle (HDL-P); and HDL size], and cholesterol efflux capacity with cognitive performance in midlife women. This prospective cohort study was conducted among 503 midlife women (1234 observations) from the Study of Women's Health Across the Nation HDL ancillary study. Joint models were applied to examine associations of HDL metrics assessed at midlife (50.2 ±2.9 years, baseline of the current study) and their changes over midlife (6.1 ±3.9 years of duration) with subsequent cognitive performance [working memory (Digit Span Backward Test), processing speed (Symbol Digit Modalities Test), and episodic memory immediate and delayed recall (East Boston memory test)] assessed repeatedly (maximum 5 times) 1.5 ±1 years later over 7.72 ± 4.10 years of follow up. Higher total HDL-P and smaller HDL size at midlife were associated with a better subsequent immediate recall, delayed recall and/or processing speed. Greater increase in HDL-PL, apoA-1, medium HDL-P, and total HDL-P and less increase in HDL size over midlife were associated with a better subsequent immediate and/or delayed recall. Enhancing specific serum HDL metrics during midlife could be promising in cognitive restoration, particularly memory, the initial and predominant symptom of Alzheimer's disease.

Neuroprotective mechanisms and ameliorative activities of quercetin in cisplatin-induced cerebellum neurotoxicity in rat models

Cisplatin (CP) is a highly effective antitumor agent, but its clinical use is limited due to critical adverse reactions including neurotoxicity. Quercetin (QC) is a naturally occurring phytochemical with promising bioactive effects. This study investigated the Neuroprotective mechanisms and ameliorative activities of quercetin in cisplatin-induced cerebellum neurotoxicity in rat models.The rats were randomly divided into five groups of six (n = 6) rats. Group A, served as control. Group B, received a single dose of 10 mg/kg body weight (bwt) of CP (i.p.) on the first day. Group C received 30 mg/kg bwt of QC. Group D received a single dose of 10 mg/kg bwt CP on the first day followed by 30 mg/kg bwt of QC. Group E received 30 mg/kg bwt of QC per day followed by a single dose of 10 mg/kg bwt of CP on the last day. The treatment lasted for 35 days after which the novel-object recognition memory test (NORT) was used to assess non-spatial memory function. Brain neurochemical status was assessed and brain tissues were processed for histology.Quercetin increased weight loss and cognitive performance in CP-treated rats by enhancing the exploration of unfamiliar objects. Quercetin protects the brain from CP-mediated alterations in oxidative status, as well as brain metabolic enzyme indicators. It also decreased IL-6, IL-1, and TNF-α, and NF-ĸB expression, restored brain metabolic enzyme activities, increased neurotransmitters, and prevented neuromorphological alterations.In conclusion, quercetin protects rats’ brains against CP-induced cerebellum neurotoxicity via oxidative stress inhibition and down-regulation of inflammation.

Impact of short-term total dissolved gas supersaturation on cognitive function and swimming performance in medaka (Oryzias latipes)

During the flood season, high dam discharge rates result in total dissolved gas (TDG) supersaturation. This condition causes gas bubble trauma and can lead to fish mortality, which poses a significant threat to downstream river ecosystems. Assessing the ecological risks of TDG supersaturation is a challenge in waterpower-intensive river basins worldwide. Few studies have explored the impact of TDG supersaturation on fish behaviours, such as aggression and memory, which are crucial for feeding, reproduction, and predator avoidance. In this study, behavioural tests were conducted in a T-maze to investigate the effects of acute TDG supersaturation on swimming behaviour, aggression, and memory in medaka (Oryzias latipes). The results demonstrated that medaka exposed to TDG levels of 115% and 130% for 2 h had significantly reduced swimming performance.At TDG levels of 100%, 115% and 130%, medaka activity rates in the mirror arm of the maze in the mirror test were 44.34 ± 12.88%, 40.27 ± 15.44% and 35.35 ± 16.07%, respectively. Similarly, the activity rates of medaka in the active stimulus arm of the maze in the memory test were 50.35 ± 14.75%, 40.76 ± 12.51% and 35.35 ± 18.47%, respectively. The behaviour of medaka changed with increasing TDG supersaturation. These findings contribute to the development of an ecological risk assessment model for TDG supersaturation based on memory and aggression in fish and provide data for developing management strategies to mitigate the adverse effects of TDG supersaturation.

Information accumulation on the item versus source test of source monitoring: Insights from diffusion modeling.

Source monitoring involves attributing previous experiences (e.g., studied words as items) to their origins (e.g., screen positions as sources). The present study aimed toward a better understanding of temporal aspects of item and source processing. Participants made source decisions for recognized items either in succession (i.e., the standard format) or in separate test blocks providing independent measures of item and source decision speed. Comparable speeds of item and source decision across the test formats would suggest a full separation between item and source processing, whereas different speeds would imply their (partial) temporal overlap. To test these alternatives, we used the drift rate parameter of the diffusion model (Ratcliff, Psychological Review, 85, 59-108, 1978). We examined whether the drift rates, together with the other parameters, assessed separately for the item and source decision varied as a function of the test format. Threshold separation and nondecision time differed between the test formats, but item and source decision speeds represented by drift rates did not change significantly. Thus, despite facilitation on the source decision when the item decision was immediately followed by a test for source memory than when item and source were tested in separate blocks, findings did not suggest that source information already begins accumulating in the item test in the standard format. We discuss the temporal sequence of item and source processing in light of different assumptions about the contribution of familiarity and recollection.

Investigating the relationship between cognitive impairment and brain white matter tracts using diffusion tensor imaging in patients with prolactinoma.

Cognitive impairment is known to occur in patients with prolactinoma, but the underlying mechanism is unclear. To evaluate cognitive function in patients with prolactinoma and to investigate the basis of possible cognitive impairment in brain white matter changes using diffusion tensor imaging (DTI). 37 consecutive patients with prolactinoma and 37 healthy controls of similar age, sex, and education were enrolled in the study. Hormone levels were determined in all participants, comprehensive neuropsychological testing was performed, and DTI was used to reconstruct and evaluate white matter tracts. In patients with prolactinoma, short- and long-term visual and verbal memory, attention, concentration, and executive and language functions were impaired compared to the healthy group. When comparing the DTI results, lower fractional anisotropy (FA) values were found in the patients' right uncinate fasciculus (R-UF), indicating neuronal damage. After applying the Bonferroni correction, the two groups had no significant difference in 42 tracts (p > 0.0012 for all). A positive correlation was found between poor FA scores on the R-UF and low scores on long-term memory, category and letter fluency tests. In addition, patients with hypoprolactinemia had the worst short-term memory scores, while normoprolactinemia had the best scores. Also, the poorer R-UF FA values were found in the patients with hypoprolactinemia and the highest in those with normoprolactinemia. This study is the first to investigate reasons for cognitive dysfunction in patients with prolactinoma by DTI. No significant structural changes were found in brain tracts of patients with prolactinoma. Still, there may be a link between potential damage in the R-UF and cognitive dysfunction, and further research is needed. In addition, the results showed that the development of hypoprolactinemia is associated with cognitive dysfunction and emphasized that overtreatment should be avoided.

Davunetide sex-dependently boosts memory in prodromal Alzheimer’s disease

BackgroundThe tauopathy inhibitor, davunetide shows sex-dependent efficacy in women suffering from progressive supranuclear palsy. Extending these findings to prodromal Alzheimer’s disease, we submitted a double-blind, placebo-controlled, 12 weeks/16 weeks follow-up, davunetide clinical trial results in amnestic mild cognitive impairment (ClinicalTrials.gov ID NCT00422981), to a sex-dependent analysis.MethodsOne hundred forty-four individuals, separated into eight groups (1:2 placebo—and 2 doses, 5 mg davunetide/daily or 15 mg davunetide/twice-daily, with matching placebo intranasal volumes), were evaluated.ResultsSignificant dose-dependent cognitive increases were observed in men compared to women with a test of delayed (12 ss) visual matching to the sample. In a test of semantic working memory and attention (digit span), women showed a significant low-dose placebo effect, ensuing in a high dose significant davunetide improvement, over the matched placebo. Correlating anxiety with cognition showed sex-opposing results, with women depicting significant anxiety correlations with delayed matching to sample.DiscussionIn conclusion, sex-specific prodromal Alzheimer’s drug development is encouraged, with davunetide playing a lead initiative role.

Effect of tDCS combined with virtual reality for post-stroke cognitive impairment: a randomized controlled trial study protocol

BackgroundPost-stroke cognitive impairment (PSCI) not only increases patient mortality and disability, but also adversely affects motor function and the ability to perform routine daily activities. Current therapeutic approaches for, PSCI lack specificity, primarily relying on and medication and traditional cognitive therapy supplemented by a limited array of tools. Both transcranial direct current stimulation (tDCS) and virtual reality (VR) training have demonstrated efficacy in improving cognitive performance among PSCI patients. Previous findings across various conditions suggest that implementing a therapeutic protocol combining tDCS and VR (tDCS - VR) may yield superior in isolation. Despite this, to our knowledge, no clinical investigation combining tDCS and VR for PSCI rehabilitation has been conducted. Thus, the purpose of this study is to explore the effects of tDCS - VR on PSCI rehabilitation.MethodsThis 4-week, single-center randomized clinical trial protocol will recruit 200 patients who were randomly assigned to one of four groups: Group A (tDCS + VR), Group B (tDCS + sham VR), Group C (sham tDCS + VR), Group D (sham tDCS + sham VR). All four groups will receive conventional cognitive rehabilitation training. The primary outcome measurement utilizes the Mini-Mental State Examination (MMSE). Secondary outcome measures include the Montreal Cognitive Assessment, Frontal Assessment Battery, Clock Drawing Test, Digital Span Test, Logic Memory Test, and Modified Barthel Index. Additionally, S-YYZ-01 apparatus for diagnosis and treating language disorders assesses subjects’ speech function. Pre- and post-four-week intervention assessments are conducted for all outcome measures. Functional near-infrared spectroscopy (fNIRS) is employed to observe changes in oxygenated hemoglobin (HbO), deoxy-hemoglobin (HbR), and total hemoglobin (HbT) in the cerebral cortex.DiscussionOur hypothesis posits that the tDCS - VR therapy, in opposed to individual tDCS or VR interventions, could enhance cognitive function, speech ability and daily living skills in PSCI patients while concurrently augmenting frontal cortical activity. This randomized study aims to provide a robust theoretical foundation supported by scientific evidence for the practical implementation of the tDCS - VR combination as a secure and efficient PSCI rehabilitation approach.Trial registrationChictr.org.cn Identifier: ChiCTR2300070580. Registered on 17th April 2023.

Personal choice shields against affective influences on effort in a "do your best" task: Effects on cardiac response.

This experiment (N = 113) tested whether personal choice vs. external assignment of task characteristics moderates the effect of incidental affective stimulation on effort-related cardiovascular response in a "do your best" task context. When participants could choose themselves the color of the stimuli (i.e., a series of letters to be recalled) used in a memory test, we expected high task commitment and willingness to mobilize resources, strong action shielding, and thus low receptivity for incidental affective influences. By contrast, when the color was externally assigned, we expected low willingness to mobilize resources, weak action shielding, and thus strong affective influences on effort. As predicted, participants in the assigned color condition showed stronger cardiac pre-ejection period reactivity during task execution when exposed to sad music than when exposed to happy music. These music effects did not appear among participants who could personally choose the color. Here, effort stayed high independently of the happy or sad background music. The present study demonstrates the moderating effect of personal choice on resource mobilization in a task of unfixed difficulty with happy and sad background music as incidental affective influence.

Memory compromise at extended delays in people with new-onset epilepsy.

Memory is one of the most sensitive markers of cognitive compromise in people with new-onset epilepsy. Nonetheless, around half of these cases score within the normal range on standard memory testing. Here we explore whether memory retention at a 1-week delay reveals otherwise undetected memory compromise in such individuals, and how it relates to subjective memory complaints and mood. Using a prospective design, 38 adults with new-onset epilepsy underwent baseline memory screening via telephone using an abbreviated Rey Auditory Verbal Learning Test (RAVLT). Psychological screening occurred via online questionnaires. One week later, without forewarning, participants completed three follow-up memory tasks. Of particular focus, we explored longer-term memory performances and forgetting trajectories in those individuals (n = 23) who demonstrated normal memory performances (scores >10th percentile) at baseline (30-min delay). Outcomes were compared to 32 healthy controls, matched for age, sex, and education. As a group, people with epilepsy performed worse than controls on all memory measures, with 44 percent impaired at baseline testing. Of those unimpaired at baseline, the rate and volume of information loss over 1 week was significantly greater than for controls. Contextual memory performance at 1 week was also significantly poorer for people with epilepsy. At the individual level, the prevalence of impaired forgetting was not significantly different between patients and controls. Subjective memory complaints were not related to any objective tests but were strongly related to self-reported mood and anxiety symptoms. People with new-onset epilepsy show reduced memory at short and extended intervals. For those showing normal memory at baseline, information does appear to be forgotten more quickly than in healthy controls, though the effect is not large. The findings indicate that while extended delay memory testing is not essential in all new epilepsy cases, it could provide useful information for particular individuals. Memory problems are common in people with epilepsy shortly after seizure onset, however, many individuals still show normal memory performances on standard neuropsychological testing. Through testing memory at an extended timepoint (1 week), our study found that on average, these individuals showed a slightly quicker rate of forgetting over a 1-week period than people without a brain condition. Self-reported memory complaints in people with new epilepsy were unrelated to their actual memory skills on testing at short and long timepoints but were rather linked to lower mood and quality of life.

Physiological and behavioural implications of the portosystemic shunt in C57Bl/6J mice.

A significant fraction of the popular inbred C57Bl/6J mice show structural and biochemical features of the congenital portosystemic shunt (PSS). How this hepatic abnormality affects physiological and behavioural parameters has not been explored in detail. Here, we confirmed the frequent occurrence of the PSS in C57Bl/6J mice by three different methods. We screened a cohort of 119 C57Bl/6J mice for total bile acids (TBA) in plasma, identified 11 animals (9.2%) with high TBA (>11µm; 171.1 ± 76.8µm), and confirmed PSS presence in that subset by magnetic resonance angiography and 1H-magnetic resonance spectroscopy of brain metabolites in the hippocampal area. In addition to the high glutamine and low myo-inositol levels, we detected lower levels of several neurotransmitters and metabolites in the hippocampus, higher brain weight and volume, as well as enhanced brain glucose utilisation in the PSS mice. We also observed differences in peripheral organ weights, haematological cell counts and clinical chemistry parameters in C57Bl/6J mice with and without PSS. Animals with PSS were slightly hyperlocomotive, had better balance on the rotarod, showed altered gait properties, and displayed attenuated fear memory in the fear conditioning test. Furthermore, we revealed a significant alteration of the pharmacokinetic profile of diazepam in C57Bl/6J mice with PSS. Our data support previous reports of hepatic disturbances and demonstrate an altered neurobiological phenotype in C57Bl/6J mice with PSS. Such congenital differences between inbred C57Bl/6J littermates may significantly distort experimental outcomes of pharmacological, behavioural and genetic studies. KEY POINTS: A significant proportion of C57Bl/6J mice, an inbred strain popular in preclinical research, have congenital portosystemic shunts (PSS) that allow venous blood to enter systemic circulation bypassing the liver. In this study, we extended existing knowledge of PSS consequences, particularly with respect to the effects on brain structure and function. We demonstrated that C57Bl/6J mice with PSS differ from their normal counterparts in brain size and contents of several neuroactive substances, as well as in peripheral organ weights, rate of glucose utilisation, blood cell counts and blood clinical chemistry parameters. C57Bl/6J mice with PSS showed altered locomotor behaviour, performed worse in a memory test and had abnormal blood pharmacokinetics of a benzodiazepine drug after a single administration. PSS presence may significantly complicate the interpretation of experiments in C57Bl/6J mice; therefore, we propose that before their use in biomedical studies, these mice should be screened with a simple blood test.

Amyloid-β oligomers trigger sex-dependent inhibition of GIRK channel activity in hippocampal neurons in mice.

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by amyloid plaques and cognitive decline, the latter of which is thought to be driven by soluble oligomeric amyloid-β (oAβ). The dysregulation of G protein-gated inwardly rectifying K+ (GIRK; also known as Kir3) channels has been implicated in rodent models of AD. Here, seeking mechanistic insights, we uncovered a sex-dependent facet of GIRK-dependent signaling in AD-related amyloid pathophysiology. Synthetic oAβ1-42 suppressed GIRK-dependent signaling in hippocampal neurons from male mice, but not from female mice. This effect required cellular prion protein, the receptor mGluR5, and production of arachidonic acid by the phospholipase PLA2. Although oAβ suppressed GIRK channel activity only in male hippocampal neurons, intrahippocampal infusion of oAβ or genetic suppression of GIRK channel activity in hippocampal pyramidal neurons impaired performance on a memory test in both male and female mice. Moreover, genetic enhancement of GIRK channel activity in hippocampal pyramidal neurons blocked oAβ-induced cognitive impairment in both male and female mice. In APP/PS1 AD model mice, GIRK-dependent signaling was diminished in hippocampal CA1 pyramidal neurons from only male mice before cognitive deficit was detected. However, enhancing GIRK channel activity rescued cognitive deficits in older APP/PS1 mice of both sexes. Thus, whereas diminished GIRK channel activity contributes to cognitive deficits in male mice with increased oAβ burden, enhancing its activity may have therapeutic potential for both sexes.

The Effect of Super Brain Yoga on Concentration, Memory, and Academic Progress in Nursing Students: A Quasi-Experimental Study.

During university life, students often face significant changes in relationships and academic pressures. Given the stressors faced by nursing students and the importance of their academic success, the study aimed to assess the impact of Super Brain Yoga on nursing students' concentration, memory, and academic progress. This quasi-experimental study was conducted on 59 nursing students at Near East University in Cyprus from February to June 2023. The intervention group (N=29) performed Super Brain Yoga three times a week for two months, while the control group (N=30) continued the usual routines. Data were collected using the demographic questionnaire, Wechsler's memory test, Concentration test, and the semester grade point average. Data analysis was performed using independent and paired t-test, chi-square, and ANCOVA using SPSS software version 26, with a significance level of P˂0.05. The study revealed a significant difference in total memory scores (P<0.001) and its subscales including personal and public information (P<0.001), orientation (P<0.001), mental control (P<0.001), logical memory (P=0.002), repeating numbers (P<0.001), visual memory (P<0.001), and learning associations (P=0.003) between the experimental and control groups after the intervention. Findings revealed a significant difference between the two groups in the reaction time (P=0.003) and the error of the reverse counting (P=0.021) following the intervention. After the intervention, based on ANCOVA test with adjusting the baseline values, there was no statistically significant difference in the semester mean of Grade Point Average between the two groups (95% confidence interval, P=0.657). Super Brain Yoga is a non-invasive intervention that can improve memory, concentration, and cognitive abilities in nursing students.

Measuring the impact of treatment on memory functions in pediatric posterior fossa tumor survivors using diffusion tensor imaging

Background and purposeThe aim of the present prospective exploratory study was to investigate the long-term impact of treatment on brain structure integrity and memory functions in pediatric posterior fossa tumor (PFT) survivors using diffusion tensor imaging (DTI), to determine whether the latter could provide useful biomarkers of memory impairment. Material and MethodsSixty participants were included in this study, divided into three groups: 22 irradiated PFT, 17 non-irradiated PFT, and 21 healthy controls. All underwent memory tests and multimodal MRI, including a DTI sequence. Mean diffusivity and fractional anisotropy values were extracted for bilateral brain structures involved in memory, in order to carry out between-group comparisons and calculate correlations with memory test scores and radiotherapy doses. Statistical tests were two-sided, and p values < 0.05 were considered statistically significant. ResultsDTI metrics were significantly higher for irradiated PFT survivors than in non-irradiated PFT survivors and controls (p < 0.05). Memory test scores were significantly lower for PFT survivors, particularly irradiated patients (p < 0.02), and were correlated with DTI metrics.(−0.27 < r < -0.62, p < 0.04). DTI metrics were correlated with either total or maximum dose for some structures. ConclusionPreliminary results of this study point to microstructural damage in memory-related brain areas in PFT survivors, particularly in irradiated patients, and identify DTI metrics as potential biomarkers of memory deficit.

Exercise, memory, and the hippocampus: Uncovering modifiable lifestyle reserve factors in refractory epilepsy

Physical exercise is an emerging target for improving cognition in aging and neurological disease. Due to the beneficial impact of exercise on hippocampal health and the vulnerability of the hippocampus in medication-resistant temporal lobe epilepsy (TLE), exercise could present a promising intervention in TLE. We investigated whether exercise engagement is associated with verbal memory function and hippocampal integrity in 29 young to middle-aged adults with refractory TLE and 21 demographically matched controls. Participants completed a self-reported questionnaire of weekly exercise, three tests of verbal memory, and a subset (n = 44) underwent structural MRI. Individuals with TLE self-reported lower exercise scores than controls across all levels of exercise intensity (p < 0.001). In TLE, greater exercise engagement was associated with better verbal memory (word-list recall and associative learning; rho = 0.46–0.47; ps FDR < 0.05), and with larger contralateral hippocampal volumes (rho = 0.61; p < 0.01). These effects remained significant when controlling for several clinical and demographic factors. These findings suggest that exercise may be a cognitive reserve factor in TLE, potentially mitigating memory decline by enhancing contralateral hippocampal integrity. With future replication and longitudinal investigation, exercise holds promise as a low-cost and accessible modifiable lifestyle target for improving cognitive health in individuals with refractory TLE

Normative data for tests of visuo-spatial, visuo-constructional skills, and visual memory for Spanish-speaking adults in the United States.

The Rey-Osterrieth Complex Figure Test (ROCFT) and the Clock Drawing Test (CDT) are commonly used in clinical practice. The ROCFT measures constructional praxis, visual perception, and visuospatial learning and memory, and the CDT assesses for visuospatial, constructional, and executive difficulties. Several neurological disorders are associated with visuospatial and visuo-constructional impairments, yet reliable normative data accounting for sociodemographic and acculturative variables are scarce for Hispanics living in the U.S. To generate normative data for the ROCFT and CDT in a Spanish-speaking adult population living in the U.S. The sample consisted of 245 cognitively healthy adults recruited from several states in the U.S. Each participant was administered the ROCFT and CDT as part of a larger cognitive battery. The ROCFT and CDT were normed using a Bayesian approach. Age, age2, education, sex, acculturation, and language proficiency were included as predictors in the analyses. ROCFT performance was associated with education and age, particularly as they interacted with Spanish language proficiency and time spent in the U.S. Education was significantly associated with recall abilities and a lower memory recall on the ROCFT. Age was found to vary depending on a person's bilingual abilities. Sex did not emerge as a predictor of performance, and it did not interact significantly with other variables. This is the first study to include acculturation and language proficiency variables in the creation of norms for the assessment of visuo-constructional abilities. This study will have a large impact on the practice of neuropsychology in the U.S.

The neuropsychological impacts of COVID-19 in non-hospitalized patients with long COVID and brain fog.

Coronavirus disease 2019 (COVID-19) causes persistent symptoms, including brain fog. Based on limited research on the long-term consequences of mild COVID-19, which has yielded inconsistent results, we investigated which cognitive functions were most affected by COVID-19 in non-hospitalized Asian patients with long-term COVID and subjective cognitive complaints. Fifty-five non-hospitalized patients with long COVID and brain fog (24 males and 31 females, mean age: 45.6 ± 14.6 years, mean duration of education: 14.4 ± 3.0 years) were recruited. Neuropsychological assessments included screening tests for overall cognition, and comprehensive tests for memory, executive function, processing speed, and subjective emotional and disease symptoms. Cognitive test scores were converted into Z-scores. Moreover, principal component analysis (PCA) was employed to define cognitive domains across subtest scores. Comprehensive assessments revealed cognitive impairment in 69.1% of patients (<1.5 standard deviation in at least one test). The processing speed (27.3%), memory recall (21.8%), memory learning (20.0%), and inhibitory control (18.2%) were the most affected areas. Self-reported anxiety and depression were observed in 35% and 33% of patients, respectively. Furthermore, the degree of self-anxiety can be used to predict learning performance. Nearly 70% of patients with subjective cognitive complaints and long COVID had objective cognitive impairments. A comprehensive evaluation is essential for patients with long COVID and brain fog, including those with mild symptoms.

Persistent activity during working memory maintenance predicts long-term memory formation in the human hippocampus.

Working memory (WM) and long-term memory (LTM) are often viewed as separate cognitive systems. Little is known about how these systems interact when forming memories. We recorded single neurons in the human medial temporal lobe while patients maintained novel items in WM and completed a subsequent recognition memory test for the same items. In the hippocampus, but not in the amygdala, the level of WM content-selective persistent activity during WM maintenance was predictive of whether the item was later recognized with high confidence or forgotten. By contrast, visually evoked activity in the same cells was not predictive of LTM formation. During LTM retrieval, memory-selective neurons responded more strongly to familiar stimuli for which persistent activity was high while they were maintained in WM. Our study suggests that hippocampal persistent activity of the same cells supports both WM maintenance and LTM encoding, thereby revealing a common single-neuron component of these two memory systems.

Does Mild and Moderate Hearing Loss Affect Verbal Working Memory and Language Skills in Children?

Introduction: For a comprehensive approach in children with hearing loss (HL), some cognitive and language skills should also be considered, along with auditory skills. The main aim of this study was to evaluate the working memory and language skills in children with mild to moderate HL. Methods: Forty children with mild to moderate HL between the ages of 4 and 9 years were included in this study. The children with mild and moderate HL were evaluated in two groups. The Meaningless Word Repetition test, Test of Language Development-Primary test, and Meaningful Auditory Integration Scale were administered to assess working memory, language skills, and auditory perception, respectively. Also, the relationship between language and memory skills was evaluated. Results: The study found statistically significant correlations between language skills and working memory test scores. Additionally, statistically significant differences were found between children with mild and moderate HL in terms of language and memory skills (p < 0.001). Conclusion: The children with moderate HL demonstrated poorer performance compared to those with mild HL. Even if it is mild, the degree of HL affects children’s language and memory skills. It is emphasized that the relationship between language and working memory should be taken into consideration in auditory rehabilitation programs for these children.

Comparison of Memory, Balance and Fear of Falling in Older Women After Performing Yoga and Square-stepping Exercises

Objectives Most falls in the elderly occur due to physical and cognitive risk factors. This study aims to compare the effect of two types of mind-body exercises, yoga and square-stepping exercise (SSE), on memory, balance, and fear of falling in older women. Methods &amp; Materials A quasi-experimental study was conducted on 20 elderly women with an age range of 60 to 70 years. Participants were selected through purposive sampling and were randomly assigned to yoga and Square-Stepping groups. Both groups did exercise for 12 weeks and participated in a pre-test and post-test. The Wechsler memory test, stork test, berg balance test, and international falls efficacy scale were used to measure memory quotient, static balance, dynamic balance, and fear of falling, respectively. Analysis of variance with repeated measures was conducted to analyze the data Results The mean scores of memory quotient in the two groups after exercises were significantly higher than before exercises (F(1, 18)=32.692, P&lt;0.001, η2=0.645). The mean static balance time in the yoga group was significantly higher than in the SSE group (F(1, 18)=60.755, P&lt;0.001, η2=0.771). Furthermore, the mean dynamic balance score in the SSE group was significantly higher than in the yoga group (F(1, 18)=7.714, P=0.012, η2=0.300). In addition, the mean square of fear of falling in the SSE group was significantly lower than in the yoga group (F(1, 18)=11.777, P=0.003, η2=0.396). Conclusion It seems that square stepping exercises can also be used as a simple exercise program to improve physical and cognitive functions in older women.

Contextual memory bias in emotional events: neurobiological correlates and depression risk

BackgroundContextual memory loss of emotional events plays a critical role in depression psychopathology. Individuals with depression, clinical or subclinical, exhibit enhanced and impaired memory for emotionally negative stimuli and context in an event, respectively. This suggests that contextual encoding may fail because of attentional interference caused by concurrent negative stimuli, possibly leading to contextual memory loss as a depression risk. Amygdala–prefrontal connectivity and cortisol may underlie the mechanism; however, the relationships remain unknown. MethodsOne hundred twenty participants, including 34 with subclinical depression, underwent behavioral tasks, functional magnetic resonance imaging (fMRI) scans, and saliva collection. Encoding and 24h later recollection performance of visuoperceptual/spatial/temporal context in a series of events, where fearful (vs. neutral) faces appeared, were measured via contextual memory tasks. Overgeneral autobiographical memory (OGM), a more remote form of contextual memory loss, was also assessed via the Autobiographical Memory Test. Amygdala connectivity was measured by fMRI during attentional interference by fearful (vs. neutral) faces to differentiate selective attention from encoding. Basal cortisol levels were assayed through saliva collected at encoding during the visit day and across 2 consecutive days in the following week (12 time points in total). We explored whether contextual memory encoding failure would explain depressive symptoms through OGM under possible moderation of amygdala connectivity and cortisol. ResultsIn individuals with subclinical depression compared to those without, fearful faces disturbed memory encoding of the visuoperceptual context rather than 24h later recollection, while neutral faces in their temporal proximity contrastingly augmented it. The more the contextual memory encoding bias (fearful vs. neutral) intensified, the more the amygdala’s functional connectivity with the ventromedial prefrontal cortex (vmPFC) weakened. Higher total cortisol output was correlated with poorer 24-h later recollection of the temporal context, although at a trend level. Moderated mediation effects of the amygdala-vmPFC connectivity and cortisol were non-significant; however, contextual encoding bias explained depressive symptoms through negatively valenced OGM. ConclusionsNegative stimuli appearing in an event might impair memory encoding of the visuoperceptual context under attentional interference, represented as weakened amygdala-vmPFC connectivity implicated in emotion-related attentional dysregulation. Conversely, negative stimuli might enhance temporally proximal visuoperceptual encoding after their disappearance. Contextual encoding bias could explain the overgeneralization (or lower coherence) of autobiographical memory and increase the risk of depression. The possible role of cortisol in recollecting the context of emotional events warrants further investigation.