Assessment Of Memory Function Research Articles

Feasibility of mobile app‐based assessment of memory functions: Insights from a citizen science study

AbstractBackgroundMobile app‐based, high‐frequency monitoring of cognition holds the promise to facilitate the individual detection of cognitive change. However, there are several factors in everyday life that potentially influence estimates of cognitive performance in an unsupervised remote test setting. Characterizing these factors is critical to guide the interpretation of results from mobile app‐based studies of cognitive function in the future.MethodsWe conducted a Germany wide Citizen Science Project (after accreditation with the Citizen Science Portal of the German Ministry for Science and Education) with the goal to identify everyday life factors influencing cognitive performance estimates acquired via smartphone‐based assessments. To that end, every participant was pseudo‐randomly assigned to one of three memory tests: 1) pattern separation of objects and scenes (Berron et al., 2018, 2019); 2) complex (photographic) scene recognition memory (Düzel et al., 2011, 2018); 3) pattern completion of object‐in‐scene associations. Participants were asked to perform one test per week over a period of 15 weeks.Results1765 participants (70% female) completed 7900 weekly test sessions. The age‐range of participants was between 18 and 89 years of age. Mean age was 53 (SD=15). We found significant effects of age, time of the day of test performance, time between encoding and retrieval as well as the screen size of the mobile device. Further, our results indicate minor or even no practice effects with repeated tests and indicate that between 4‐5 test sessions are sufficient in order to define a measure of baseline performance.ConclusionOur results indicate several factors influencing cognitive measures in an unsupervised setting of remote smartphone‐based assessment of memory functions. While some factors were specific to only some tests, most factors were associated to all three tests suggesting that they are of general nature. Finally, several sets of different parallel test versions for each memory test resulted in marginal practice effects with repeated assessments.

Effects of memantine on the passive avoidance test in young rats

Alzheimer’s disease (AD) is a long-lasting progressive neurodegenerative disease that degrades memory and cognitive function and is often complicated by disorientation and other psychiatric syndromes. At present, to improve the condition of patients with AD, for their treatment, use the drug memantine. The drug is a noncompetitive antagonist of NMDA glutamate receptors in the brain. The present experiments aimed to test the influence of memantine on the memory processes in rats. We used the passive avoidance test “Stepdown”. The latter is used to assess memory function based on the association formed between a particular environment that an animal is learning to avoid and a negative stimulus in the form of a weak electric shock to the feet. We found that memantine significantly, twice, decreased the latency time step-down from the platform in rats during their familiarization with the chamber. The rats became more determined and less afraid of the unknown environment under memantine. Memantine significantly affected the emotionality of young rats, which leads to errors in the passive avoidance test. However, it did not impair memory. It can be concluded that memantine induces a shift toward greater excitability in rats.

Global Cognitive Performance and Assessment of Memory Functions in Obstructive Sleep Apnea.

Cognitive problems in patients with obstructive sleep apnea have been suspected since the 1980s. Several studies have investigated different cognitive domains. A similar widespread survey has not been done in the Bulgarian population. This study aimed to evaluate global cognitive functioning and memory function in patients with obstructive sleep apnea and to examine the potential influence of comorbidities on cognitive functions. The study examined the neurocognitive profile of 103 consecutive patients newly diagnosed with OSA and 31 healthy controls. A list of inclusion and exclusion criteria was developed. Sleep breathing was examined in both groups. The other methods were: a medical history of patients, clinical examination, neuropsychological assessment, statistical analysis. The study found that the global cognitive functioning of patients with OSA and the memory function was impaired. Short-term memory has been found affected predominantly. Only obesity was distinguished as a major factor relevant to the severity of cognitive changes in the study group. A statistically significant difference between the groups with and without obesity was found for the applied memory tests, except for the delayed recall and word recognition. The duration of exposure to hypoxia and sleep fragmentation is important for the severity of cognitive deficits. The results confirmed this theory showing that this factor is among the major severity factors. The study found that the global cognitive functioning of patients with OSA, as well as memory function, were impaired. The role of comorbidities is complex and far from clear.

Assessment of Memory Function in Pilocarpine-induced Epileptic Mice.

Cognitive impairment is one of the most common comorbidities in temporal lobe epilepsy. To recapitulate epilepsy-associated cognitive decline in an animal model of epilepsy, we generated pilocarpine-treated chronic epileptic mice. We present a protocol for three different behavioral tests using these epileptic mice: novel object location (NL), novel object recognition (NO), and pattern separation (PS) tests to evaluate learning and memory for places, objects, and contexts, respectively. We explain how to set the behavioral apparatus and provide experimental procedures for the NL, NO, and PS tests following an open field test that measures the animals' basal locomotor activities. We also describe the technical advantages of the NL, NO, and PS tests with respect to other behavioral tests for assessing memory function in epileptic mice. Finally, we discuss possible causes and solutions for epileptic mice failing to make 30 s of good contact with the objects during the familiarization sessions, which is a critical step for successful memory tests. Thus, this protocol provides detailed information about how to assess epilepsy-associated memory impairments using mice. The NL, NO, and PS tests are simple, efficient assays that are appropriate for the evaluation of different kinds of memory in epileptic mice.

Assessment of Memory Function in Pilocarpine-induced Epileptic Mice

Assessment of Memory Function in Pilocarpine-induced Epileptic Mice

Effect of Supplementation of a Whey Peptide Rich in β-Lactolin on Cognitive Performance in Healthy Adults: Randomized, Double-Blind, Placebo-Controlled Study

IntroductionWith rapid increase of aging worldwide, the number of people suffering from cognitive decline and dementia has been rapidly increasing. Numerous epidemiological and clinical studies have shown that consumption of dairy products have beneficial effects on cognitive decline and dementia in elderly. Our previous demonstration using pharmacologically-induced amnesia model mice identified tryptophan-tyrosine-related peptides, especially glycine-threonine-tryptophan-tyrosine (GTWY) of lactotetrapeptide, b-lactolin, as responsible agents improving cognitive decline in whey digestions, and we have originally developed GTWY-rich whey peptide by a specific enzymatic digestion. However, the effect of GTWY-rich whey peptide on cognitive functions in human has not been investigated. The present study is the first clinical trial evaluating the effects of GTWY-rich whey peptide on cognitive functions in a randomized, double-blind, placebo-controlled design.MethodsHealthy middle to older adults, aged from 45 to 64 years, with a self-awareness of cognitive decline were recruited. 101 eligible subjects received either whey peptide tablets containing 1 g of the GTWY-rich whey peptide per day, which included 1.6 mg of GTWY, (N = 50) or placebo containing the same amount of maltodextrin (N = 51) for 12 weeks. Changes of cognitive functions from 0 week of the intervention were assessed using neuropsychological tests assessing memory functions (word recall, story recall and verbal fluency test) and attention and executive functions (stroop test, digit span, and paced auditory serial addition test) at 6 and 12 weeks.ResultsThe change of verbal fluency test (VFT) score evaluating long-term memory retrieval at 12 weeks in whey peptide group tended to be higher than that in placebo group. Subgroup analysis showed that in the subjects with high-level of subjective fatigue measured by visual-analog scale, the changes of VFT, stroop test evaluating inhibition of executive functions and subjective memory function test at 6 weeks in whey peptide group were significantly higher than those in placebo group. The change of VFT score was also significantly higher in subjects with high fatigue measured by profile of mood status.Discussion and ConclusionsThe present study suggests that consumption of GTWY-rich whey peptide improve cognitive functions, especially memory retrieval and executive function, in healthy middle to older adults, with high subjective fatigue. It is also suggested that prefrontal cortex functions, especially dorsolateral prefrontal cortex is associated with the effects of the whey peptide. Consumptions of 1 g GTWY-rich whey peptide in daily life are safe and easy, which might be a practical approach to support cognitive function.

Evaluación preliminar de una versión pictórica y abreviada del Free and Cued Selective Reminding Test

IntroductionA picture version of the Free and Cued Selective Reminding Test (FCSRT) would assist in the assessment of memory function in patients with low levels of schooling. A shortened version would improve the test's applicability. ObjectivesTo analyse the diagnostic usefulness of a shortened picture version of the FCSRT for distinguishing patients with amnestic mild cognitive impairment (aMCI) from controls, without excluding participants with a low level of schooling. MethodsPhase I study of a diagnostic evaluation (convenience sampling; pre-test prevalence 50%). A blinded researcher independently administered the FCSRT to 30 patients with aMCI and 30 controls matched for age, sex, level of schooling and literacy, using images and omitting the usual 30-minute delayed recall item. Three variables were recorded: free recall, total recall, and cue efficiency. Diagnostic accuracy was calculated using receiver operating characteristic curves and the area under the curve. The Youden index was used to identify optimal cut-off points. ResultsOf all participants, 41.7% had not completed primary education. There were no differences between groups as regards sociodemographic variables. Area under the curve was excellent for free recall (0.99), total recall (0.95), and cue efficiecy (0.93). The optimal cut-off points were 21/22, 43/44, and < 0.77, respectively. ConclusionsThis preliminary analysis shows that a shortened picture version of the FCSRT may be useful and applicable for the diagnosis of aMCI without excluding individuals with a low level of schooling.

An Integrated Analysis of Risk Factors of Cognitive Impairment in Patients with Severe Carotid Artery Stenosis

ObjectiveTo investigate cognitive dysfunction in patients with carotid artery stenosis (CAS) and potential risk factors related to cognitive-especially memory-dysfunction. MethodsForty-seven patients with carotid artery stenosis were recruited into our study cohort. The Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) were adopted to assess cognitive function, the Wechsler Memory Scale (WMS) to assess memory function, high-resolution MRI and enhanced ultrasound to evaluate carotid plaques, and computed tomography perfusion (CTP) imaging to evaluate intracranial blood perfusion. Single-factor analysis and multiple-factor regression analysis were used to analyze potential risk factors of cognitive impairment. ResultsMini-Mental State Examination test results showed that 22 patients had cognitive impairment, and MoCA test results showed that 10 patients had cognitive impairment. Analysis of various risk factors indicated that the average memory quotient of female patients was higher than that of males (P = 0.024). The cognitive and memory performance of those with an educational background above high school were significantly better than those of participants with high school or lower (P = 0.045). Patients with abnormal intracranial perfusion performed worse on the MMSE test (P = 0.024), and their WMS scores were significantly lower (P = 0.007). The MMSE scores and the memory quotients were significantly lower in patients with a history of cerebral infarction (MMSE, P = 0.047, memory quotient score, P = 0.018). ConclusionA history of cerebral infarction and abnormal cerebral perfusion are associated with decline in overall cognitive function and memory in patients with carotid stenosis. Being female and having an educational background above high school may be protective factors in the development of cognitive dysfunction.

The relationship between the Wechsler Memory Scale-Revised scores and whole-brain structure in patients with schizophrenia and healthy individuals

ABSTRACTIntroduction: The Wechsler Memory Scale (WMS) is a standardised battery for assessing memory functions. We aimed to investigate the relationship between all WMS scores, including subtests, and whole-brain structure in a relatively large sample.Methods: Participants were 93 patients with schizophrenia and 117 healthy individuals, all right-handed and of Japanese ethnicity, and matched for age and sex. Their memory functions were assessed using the WMS-Revised (WMS-R). Their grey and white matter structure was analyzed using voxel-based morphometry and diffusion tensor imaging.Results: Verbal memory score correlated positively with volumes of the left parahippocampal gyrus and hippocampus, while general memory score correlated positively with volumes of the left parahippocampal and fusiform gyri and hippocampus (p < 0.05, corrected), while there was no correlation with white matter fractional anisotropy values in healthy individuals. No correlation was observed between any WMS-R score and grey or white matter structure in patients.Conclusions: Using whole-brain structural magnetic resonance imaging, we found several significant correlations between WMS-R scores and grey matter volume in the brains of healthy individuals, while no correlation was found in those of patients with schizophrenia.

Hearing loss and verbal memory assessment among older adults.

Research has found that adults with hearing loss perform worse on cognitive testing than adults without hearing loss; however, heavy emphasis on tests involving auditory stimuli may overdiagnose cognitive impairment among individuals with hearing loss. This study compared visual- and auditory-verbal memory tests among adults with and without hearing loss. Forty-one adults with hearing loss (HL) and 41 age-matched adults with normal hearing (NH) completed a neuropsychological battery that included auditory and visual versions of the Hopkins Verbal Learning Testing-Revised (HVLT-R). A natural auditory condition presented HVLT-R stimuli at normal speaking volume. A crossed auditory condition presented HVLT-R stimuli to individuals with hearing loss with amplified acoustic intensity and to individuals with normal hearing under hearing loss simulation. Mixed-model ANOVA indicated significant group (HL vs. NH) by condition (visual, natural auditory, crossed auditory) interactions for HVLT-R performance, with large effect sizes. The HL group performed significantly worse than the NH group on the natural auditory version; however, the NH group performed significantly worse than the HL group on the crossed condition. The groups were equivalent on the visual condition and all other cognitive tests, showing small effect sizes. Moreover, for the HL group, visual HVLT-R correlated with other cognitive tests whereas auditory versions did not. Cognitively intact older adults with hearing loss appeared impaired on auditory-verbal memory assessment under typical administration conditions. Visual assessment of verbal memory showed evidence of superior validity and is a viable alternative method to assess memory function especially in older populations. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The Experimental Effects of Acute Exercise on Reducing the Amount of Re-Learning Needed to Enhance Memory Recall

Emerging research suggests that acute exercise may subserve episodic memory function, including both short- and long-term memory. What has yet to be investigated in the literature is whether acute exercise can increase “savings”, that is, reduce the amount of re-learning needed to enhance recall, which was the purpose of this experiment. Participant were randomized into an experimental exercise group (15-minute moderate-intensity exercise) or a time-matched control group. The Open-Trial Selective Reminding Test (OT-SRT) was used to assess memory function, which was assessed at baseline and 4-hours later. The exercise group (vs. the control group) had slightly more favorable values. For the exercise and control groups, respectively, the number of words recalled after the first exposure to the word list (outcome 1) was 6.10 (1.6) and 5.95 (1.0). In these respective groups, it took the exercise group slightly fewer trials (outcome 2) to retrieve to criterion (5.95 (1.5) vs. 6.35 (1.8)). After the 20-minute delay (outcome 3), the exercise group recalled slightly more words (12.4 (1.6) vs. 12.15 (2.0)). Similarly, after the 4-hour delay (outcome 4), the exercise group recalled slightly more words (11.55 (2.4) vs. 11.25 (2.4). Lastly, for this 4-hour delayed assessment, it took the exercise group slightly fewer trials (outcome 5) to retrieve to criterion (3.00 (0.9) vs. 3.05 (0.7)). However, for the 2 (group) x 5 (outcomes) RM-ANOVA, there was no significant main effect for group (F=0.07, P=.79, η2p=.002) or group by time interaction (F=.25, P=.90, η2p=.007). In conclusion, acute exercise was not associated with better memory function or increased savings. Future work on this novel paradigm is warranted.

Memory in children with epilepsy: Utility of the WRAML-2 in generalized and focal epilepsy syndromes

The material-specific model for memory impairment predicts that verbal memory deficits are seen with left temporal seizures, and visual memory deficits are seen with right temporal seizures (Henkin et al., 2005). In pediatric epilepsy, seizure pathology has not always yielded the expected material-specific memory profiles. This study used the Wide Range Assessment of Memory and Learning—Second Edition (WRAML-2) to assess memory functioning among pediatric patients with epilepsy. The WRAML-2 was administered to 180 youth with epilepsy during their neuropsychological evaluations. Memory and recognition scores correlated significantly with epilepsy severity variables. There were no significant differences in verbal and visual memory and recognition index scores among patients with generalized epilepsy or among those with lateralized or localized electroencephalography (EEG) patterns and lesions on imaging. However, clinically meaningful verbal versus visual discrepancy scores were significantly related to lateralized abnormalities on EEG and magnetic resonance imaging (MRI) results. Most patients with right hemisphere pathology showed the expected material-specific visual memory deficits, while fewer than 15% of the left hemisphere cases showed the expected verbal memory deficits. Over one-third of those with identified left-sided pathology showed clinically significant deficits in visual memory. Findings are incongruent with the material-specific memory model and reflect the fact that early developmental neurological insults can lead to functional reorganization/crowding effects in children with left hemisphere epilepsy. On exploratory analyses, there were no significant differences in discrepancy scores among participants with left, right, and bilateral languages on Wada and functional MRI (fMRI). However, those with right and bilateral language dominance were more likely to show discrepancies that were incongruent with the material-specific model.

Neuropsychological assessment of patients undergoing surgery due to low-grade glioma involving the supplementary motor area

ObjectiveThe aim of the study was to establish the usefulness of various neuropsychological tests in patients undergoing surgery due to low-grade glioma (LGG) involving supplementary motor area (SMA). Patients and methods21 patients diagnosed with LGG involving the SMA underwent, before and after surgery, screening tests (Mini Mental State Examination – MMSE, Montreal Cognitive Assessment – MoCA and Frontal Assessment Battery – FAB), tests to assess language functions (Addenbrook’s Cognitive Examination-III – ACE-III, phonetic fluency tests and semantic fluency tests), tests to assess memory functions (Rey’s 15-word test – RAVLT and Diagnostic Test for Brain Damage by Hillers- DCS), tests to assess executive functions (Wisconsin Card Sorting Test - WCST, Ruff Figural Fluency Test – RFFT and Trail Making Test). ResultsBefore surgery, in the screening tests the patients obtained below normal scores in the MoCA test only. After surgery, the scores of such tests were significantly worse than the scores before surgery, while the MMSE test scores continued to be within the normal range. In phonetic and semantic fluency tests, the patients obtained worse scores, both before and after surgery. The differences in the test scores between the two periods, i.e. before and after surgery, were statistically significant. Although the patients obtained worse scores both before and after surgery in the ACE III test, the differences in the test scores were not statistically significant. The scores obtained in all tests assessing the executive and memory functions before and after surgery were within the normal range. The scores in such tests (except the WCCT) dropped significantly after surgery. ConclusionsPatients diagnosed with LGG involving the SMA reveal the impairment of cognitive functions, in particular language functions. After surgery, a significant impairment of all elementary cognitive functions, such as attention, memory, language and executive functions and complex cognitive functions, occurs. The most sensitive tests to detect cognitive disorders, executive dysfunctions and speech disturbances in patients undergoing surgery due to glioma include the MoCA, FAB and Phonetic and Semantic Fluency Tests.

Memory loss and memory reorganization patterns in temporal lobe epilepsy patients undergoing anterior temporal lobe resection, as demonstrated by pre-versus post-operative functional MRI

This study was aimed to longitudinally assess memory function and whole-brain memory circuit reorganization in patients with temporal lobe epilepsy (TLE) by comparing activation potentials before versus after anterior temporal lobe (ATL) resection. Nineteen patients with medically-intractable TLE (10 left TLE, 9 right TLE) and 15 healthy controls were enrolled. Group analyses were conducted pre- and post-ATL of a novelty complex scene-encoding paradigm comparing areas of blood oxygen-level-dependent (BOLD) signal activations on functional magnetic resonance imaging (fMRI). None of the pre-operative patient characteristics we studied predicted the extent of pre- to post-operative memory loss. On fMRI, extra-temporal activations were detected pre-operatively in both LTLE and RTLE, particularly in the frontal lobe. Greater activations also were noted in the contralateral hippocampus and parahippocampus in both groups. Performing within-subject comparisons, post-op relative to pre-op, pronounced ipsilateral activations were identified in the left parahippocampal gyrus in LTLE, versus the right middle temporal gyrus in RTLE patients. Memory function was impaired pre-operatively but declined after ATL resection in both RTLE and LTLE patients. Post-operative fMRI results indicate possible functional adaptations to ATL loss, primarily occurring within the left parahippocampal gyrus versus right middle temporal gyrus in LTLE versus RTLE patients, respectively.

The Influence of Fluid Intelligence, Executive Functions and Premorbid Intelligence on Memory in Frontal Patients.

Objective: It is commonly thought that memory deficits in frontal patients are a result of impairments in executive functions which impact upon storage and retrieval processes. Yet, few studies have specifically examined the relationship between memory performance and executive functions in frontal patients. Furthermore, the contribution of more general cognitive processes such as fluid intelligence and demographic factors such as age, education, and premorbid intelligence has not been considered.Method: Our study examined the relationship between recall and recognition memory and performance on measures of fluid intelligence, executive functions and premorbid intelligence in 39 frontal patients and 46 healthy controls.Results: Recall memory impairments in frontal patients were strongly correlated with fluid intelligence, executive functions and premorbid intelligence. These factors were all found to be independent predictors of recall performance, with fluid intelligence being the strongest predictor. In contrast, recognition memory impairments were not related to any of these factors. Furthermore, age and education were not significantly correlated with either recall or recognition memory measures.Conclusion: Our findings show that recall memory in frontal patients was related to fluid intelligence, executive functions and premorbid intelligence. In contrast, recognition memory was not. These findings suggest that recall and recognition memory deficits following frontal injury arise from separable cognitive factors. Recognition memory tests may be more useful when assessing memory functions in frontal patients.

Subjective Memory Complaints in Portuguese Young Adults: Contributions from the Adaptation of the Prospective and Retrospective Memory Questionnaire.

Self-report instruments that allow to characterize the frequency of daily memory failures are essential for a comprehensive assessment of memory functioning. In this context, we aimed to provide preliminary evidence of validity and reliability for the European Portuguese adaptation of the Prospective and Retrospective Memory Questionnaire (PRMQ). A total of 1052 healthy participants completed an online survey with the PRMQ. The exploration of the construct validity suggested the tripartite model with a general memory, a prospective memory, and a retrospective memory factors to have the best adjustment to the data. Measurement invariance across age and sex groups was also verified. The questionnaire revealed good convergent validity with a general self-report measure of memory (0.778 < r < 0.853), and satisfactory values of internal consistency (0.779 < Cronbach’s alpha < 0.887) and of test-retest reliability (0.815 < r < 0.852). There were no prominent effects of sex and age in the PRMQ scores. Although the sample encompassed mainly younger and highly educated adults, this study presented the first evidence of validity and reliability for the European Portuguese version of the questionnaire.

The importance of hippocampal dynamic connectivity in explaining memory function in multiple sclerosis.

IntroductionBrain dynamics (i.e., variable strength of communication between areas), even at the scale of seconds, are thought to underlie complex human behavior, such as learning and memory. In multiple sclerosis (MS), memory problems occur often and have so far only been related to “stationary” brain measures (e.g., atrophy, lesions, activation and stationary (s) functional connectivity (FC) over an entire functional scanning session). However, dynamics in FC (dFC) between the hippocampus and the (neo)cortex may be another important neurobiological substrate of memory impairment in MS that has not yet been explored. Therefore, we investigated hippocampal dFC during a functional (f) magnetic resonance imaging (MRI) episodic memory task and its relationship with verbal and visuospatial memory performance outside the MR scanner.MethodsThirty‐eight MS patients and 29 healthy controls underwent neuropsychological tests to assess memory function. Imaging (1.5T) was obtained during performance of a memory task. We assessed hippocampal volume, functional activation, and sFC (i.e., FC of the hippocampus with the rest of the brain averaged over the entire scan, using an atlas‐based approach). Dynamic FC of the hippocampus was calculated using a sliding window approach.ResultsNo group differences were found in hippocampal activation, sFC, and dFC. However, stepwise forward regression analyses in patients revealed that lower dFC of the left hippocampus (standardized β = −0.30; p = .021) could explain an additional 7% of variance (53% in total) in verbal memory, in addition to female sex and larger left hippocampal volume. For visuospatial memory, lower dFC of the right hippocampus (standardized β = −0.38; p = .013) could explain an additional 13% of variance (24% in total) in addition to higher sFC of the right hippocampus.ConclusionLow hippocampal dFC is an important indicator for maintained memory performance in MS, in addition to other hippocampal imaging measures. Hence, brain dynamics may offer new insights into the neurobiological mechanisms underlying memory (dys)function.

Dietary Supplementation of Almond Prevents Oxidative Stress by Advocating Antioxidants and Attenuates Impaired Aversive Memory in Male Rats.

Scopolamine, an anti-muscarinic agent, has been shown to induce amnesia and oxidative stress similar to that observed in the older age. The present study was designed to determine the relationship between the oxidative status and memory improvement in scopolamine injected rats pre-administered with almonds. Rats (n = 8) in the almond group were administered orally with 400mg/kg almond suspension for 28days daily before the intraperitoneal injection of scopolamine (0.5mg/kg). Passive avoidance task (PAT) was used to assess memory function at the end of treatment. The present study revealed that scopolamine injection significantly impaired the memory function in rats pre-treated with saline which was accompanied by increased oxidative stress as evident by increased brain malondialdehyde (MDA) levels and reduced activities of antioxidant enzymes as compared to healthy controls. Pre-treatment with almond significantly ameliorated scopolamine-induced oxidative stress and memory dysfunction. These findings suggest that dietary supplementation with almonds may have a beneficial effect in reducing the risk of oxidative stress-induced memory loss and delaying or preventing the onset of age-related memory impairment.

Altered intrinsic brain activity and memory performance improvement in patients with end-stage renal disease during a single dialysis session.

Memory deficits are considered to have a great influence on self-management, dietary restriction and therapeutic regimen for end-stage renal disease (ESRD) patients with dialysis treatment. This study was aim to investigate the spontaneous brain activity and its relationship with memory performance in ESRD patients before dialysis (T1) and after 24h (T2) during a single dialysis session. 23 ESRD patients and 25 matched healthy controls (HCs) were scanned using functional magnetic resonance imaging (fMRI) at T1, and all patients were also scanned at T2. Amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) methods were used to evaluate the spontaneous brain activity between two groups. The Auditory Verbal Learning Test-Huashan version (AVLT-H) was performed to assess memory function. Compared with HCs, ESRD group showed a significant decreases in the immediate recall total score (IR-S), short-term delayed recall score (SR-S), and long-term delayed recall score (LR-S) at T1. IR-S, SR-S, LR-S and recognition score (REC-S) were significantly increased at T2. Compared with HCs at T1, ESRD patients showed that the lower mean ALFF (mALFF) values were mainly located in dorsolateral prefrontal cortex (DLPFC), medial frontal gyrus, and precuneus. Higher ReHo in the bilateral inferior temporal gyrus and left hippocampus and lower ReHo in the right precentral gyrus, anterior cingulate cortex were found at T1 too. The mALFF values of the DLPFC and precuneus were significantly increased during a dialysis session, while no significantly difference of ReHo region was found. Furthermore, the increased mALFF values of the DLPFC were significantly positively correlated with the improvement in the IR-S. Our results indicated that increased regional spontaneous activity of the DLPFC may reflect memory performance improvement after a single dialysis treatment, which may provide insight into the effect of hemodialysis on spontaneous brain function during a single dialysis session.

The Correlations among Depressive Symptoms, Cognitive Performance and Serum BDNF Levels in the Patients with Chronic Kidney Disease.

Objective In the current study, we investigated whether there are relations among depressive symptoms, cognitive performance and serum BDNF levels in the patients with chronic kidney disease (CKD). Methods Sixty patients with CKD and 65 healthy controls participated. Depressive symptoms were evaluated with Beck depression inventory (BDI) and Hamilton Depression Rating Scale (HDRS). Mini-Mental State Examination included in the Korean version of the Consortium to Establish a Registry for Alzheimer’s disease (MMSE-KC) assessment packet was used for the evaluation of overall cognitive function. To assess memory function, the Korean version of the Hopkins Verbal Learning Test (K-HVLT) was used. BDNF levels were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Results The CKD patients showed more depressive symptoms when compared with controls. The depressive symptoms and cognitive function were not associated with serum BDNF levels in the CKD patients. Conclusion In the current study, CKD patients had more depressive symptoms when compared controls. However, the serum BDNF levels of CKD patients were not associated with depressive symptoms and cognitive functions. These findings suggested that the serum BDNF levels may not be reflect the cognitive function and depressive mood state in the CKD patients.