Memory Dysfunction In Patients Research Articles

Alterations in Brain Morphometric Networks and Their Relationship with Memory Dysfunction in Patients with Type 2 Diabetes Mellitus.

Cognitive dysfunction, a significant complication of type 2 diabetes mellitus (T2DM), can potentially manifest even from the early stages of the disease. Despite evidence of global brain atrophy and related cognitive dysfunction in early-stage T2DM patients, specific regions vulnerable to these changes have not yet been identified. The study enrolled patients with T2DM of less than five years' duration and without chronic complications (T2DM group, n=100) and demographically similar healthy controls (control group, n=50). High-resolution T1-weighted magnetic resonance imaging data were subjected to independent component analysis to identify structurally significant components indicative of morphometric networks. Within these networks, the groups' gray matter volumes were compared, and distinctions in memory performance were assessed. In the T2DM group, the relationship between changes in gray matter volume within these networks and declines in memory performance was examined. Among the identified morphometric networks, the T2DM group exhibited reduced gray matter volumes in both the precuneus (Bonferroni-corrected p=0.003) and insular-opercular (Bonferroni-corrected p=0.024) networks relative to the control group. Patients with T2DM demonstrated significantly lower memory performance than the control group (p=0.001). In the T2DM group, reductions in gray matter volume in both the precuneus (r=0.316, p=0.001) and insular-opercular (r=0.199, p=0.047) networks were correlated with diminished memory performance. Our findings indicate that structural alterations in the precuneus and insular-opercular networks, along with memory dysfunction, can manifest within the first 5 years following a diagnosis of T2DM.

Neural mechanisms of working memory dysfunction in patients with chronic insomnia disorder

ObjectiveThis study aimed to investigate the neural mechanisms underlying working memory impairment in patients with chronic insomnia disorder (CID) using event-related potentials (ERP) and resting-state functional connectivity (rsFC) approaches. MethodsParticipants, including CID patients and healthy controls (HCs), completed clinical scales and underwent electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). EEG analysis compared reaction times, P3 amplitudes, event-related spectral perturbations (ERSP), and inter-trial phase synchronisation (ITPS) between CID patients and HCs. Subsequently, frontal regions (i.e., the Superior Frontal Gyrus [SFG] and Middle Frontal Gyrus [MFG]) corresponding to the EEG were selected as seeds for rsFC analysis. Correlation analyses were conducted to further investigate the relationship between functional connectivity abnormalities in brain regions and clinical symptom severity and P3 amplitude in CID patients. ResultsCompared to HCs, CID patients exhibited slower reaction times across all working memory conditions, with the deficits becoming more pronounced as memory load increased. ERP analysis revealed increased P3 amplitude, theta wave power, and reduced inter-trial synchrony in CID patients. rsFC analysis showed decreased connectivity of SFG-posterior cingulated cortex (PCC), SFG-MFG, and MFG-frontal pole (FP), and increased connectivity of MFG- Middle Temporal Gyrus (MTG)in CID patients. Importantly, a significant correlation was found between the rsFC of SFG-MTG and P3 amplitude during 1-back. ConclusionThis study confirms deficits in working memory capacity in patients with CID, specifically in the neural mechanisms of cognitive processing that vary depending on the level of cognitive load. Alterations in connectivity patterns within and between the frontal and temporal regions may be the neural basis of the cognitive impairment.

Serotonin 4 Receptor Brain Binding in Major Depressive Disorder and Association With Memory Dysfunction

The cerebral serotonin 4 (5-HT4) receptor is a promising novel target for treatment of major depressive disorder (MDD), and pharmacological stimulation of the 5-HT4 receptor has been associated with improved learning and memory in healthy individuals. To map the neurobiological signatures of patients with untreated MDD compared with healthy controls and to examine the association between cerebral 5-HT4 receptor binding and cognitive functions in the depressed state. This case-control study used baseline data from the NeuroPharm clinical depression trial in Denmark. Adult participants included antidepressant-free outpatients with a current moderate to severe depressive episode and healthy controls. All participants completed positron emission tomography (PET) scanning with [11C]SB207145 for quantification of brain 5-HT4 receptor binding, but only the patients underwent cognitive testing. Data analyses were performed from January 21, 2020, to April 22, 2022. The main study outcome was the group difference in cerebral 5-HT4 receptor binding between patients with MDD and healthy controls. In addition, the association between 5-HT4 receptor binding and verbal memory performance in the patient group was tested. Other cognitive domains (working memory, reaction time, emotion recognition bias, and negative social emotions) were assessed as secondary outcomes. A total of 90 patients with untreated MDD (mean [SD] age, 27.1 [8.2] years; 64 women [71.1%]) and 91 healthy controls (mean [SD] age, 27.1 [8.0] years; 55 women [60.4%]) were included in the analysis. Patients with current MDD had significantly lower cerebral 5-HT4 receptor binding than healthy controls (-7.0%; 95% CI, -11.2 to -2.7; P = .002). In patients with MDD, there was a correlation between cerebral 5-HT4 receptor binding and verbal memory (r = 0.29; P = .02). Results of this study show that cerebral 5-HT4 receptor binding was lower in patients with MDD than in healthy controls and that the memory dysfunction in patients with MDD was associated with lower cerebral 5-HT4 receptor binding. The cerebral 5-HT4 receptor is a promising treatment target for memory dysfunction in patients with MDD.

Loss of hippocampal dentation in hippocampal sclerosis and its relationship to memory dysfunction.

Hippocampal dentation (HD) is a "toothlike" morphological feature observed on the inferior aspect of the human hippocampus. It has been found that HD varies dramatically in healthy adults and is positively associated with verbal and visual memory. In this work, we evaluate the loss of HD and its association with memory dysfunction in patients with temporal lobe epilepsy (TLE) who have hippocampal sclerosis (HS). Fifty-eight unilateral HS patients with neuropsychological data were identified from a retrospective database. T1-weighted magnetization-prepared rapid acquisition gradient echo images (~1mm resolution) were upsampled to .25mm and were processed using ASHS software to obtain ultra-high-resolution segmentations and three-dimensional renderings. Dentes were counted on the epileptic and contralateral sides, and associations were tested between dentation on the epileptic versus contralateral sides and measures of verbal and visuospatial memory with respect to the dominant versus nondominant hemisphere. The median number of dentes in epileptic hippocampi was significantly lower than in contralateral hippocampi (p<.0001). Among cases with HS in the dominant hemisphere, verbal memory was significantly correlated with contralateral nondominant hemisphere dentation (r=.43, p=.04). Similarly, among cases of HS in the nondominant hemisphere, visual memory was significantly correlated with contralateral dominant hemisphere dentation (r=.48, p=.04). All other analyses were not significant. This is the first study characterizing dentation in TLE patients with HS and its memory correlates. There is marked loss of dentation in sclerotic hippocampi compared to the unaffected contralateral hippocampi. Material-specific measures of memory performance are paradoxically correlated with dentation contralateral to the side with HS, suggesting that contralateral functional capacity explains some of the variation in memory across TLE patients. HD is an important variable to consider in understanding memory loss in TLE.

Elevated Peripheral Brain-Derived Neurotrophic Factor Level Associated With Decreasing Insulin Secretion May Forecast Memory Dysfunction in Patients With Long-Term Type 2 Diabetes.

BackgroundWith the progressive course of diabetes and the decline in islet function, the cognitive dysfunction of patients aggravated.ObjectiveWe aimed to investigate the roles of brain-derived neurotrophic factor (BDNF) and the Val66Met polymorphism in mild cognitive impairment (MCI) in patients with type 2 diabetes mellitus (T2DM).MethodsA total of 169 Chinese patients with T2DM were involved and divided into long-term (diabetes duration >10 years) and short-term (diabetes duration ≤10 years) diabetes, and in each group, the patients were separated as MCI and the control. Demographic characteristics, clinical variables, and cognitive performances were assessed. The plasma BDNF level was measured via enzyme-linked immunosorbent assay. The Val66Met polymorphisms were analyzed.ResultsLong-term T2DM have lower 2 h postprandial C-peptide (p < 0.05). The BDNF level was slightly higher in patients with MCI than in the controls in each duration group without statistical significance. The relationship of BDNF to Montreal Cognitive Assessment was not proven either. However, in the long-term diabetes group, BDNF concentration remained as an independent factor of logical memory test (β = −0.27; p < 0.05), and they were negatively correlated (r = −0.267; p = 0.022); BDNF was also negatively correlated with fasting C-peptide (r = −0.260; p = 0.022), 2 h postprandial C-peptide (r = −0.251; p = 0.028), and homeostasis model assessment of insulin resistance (r = −0.312; p = 0.006). In genotypic groups, BDNF Val/Val performed better in logical memory test than Met/Met and Val/Met.ConclusionElevated peripheral BDNF level associated with declined islet function, when combined with its Val66Met polymorphism, may forecast memory dysfunction in patients with long-term T2DM.

Alterations of the intrinsic amygdala-hippocampal network in juvenile myoclonic epilepsy.

IntroductionSeveral lines of evidence suggest that the amygdala–hippocampus is involved in the epileptogenic network of juvenile myoclonic epilepsy (JME). The aim of this study was to investigate the alterations in the individual nuclei of the amygdala and hippocampal subfields, and the intrinsic amygdala‐hippocampal network of patients with JME compared to healthy controls.MethodsThis retrospective study conducted at a single tertiary hospital involved 35 patients with newly diagnosed JME, and 34 healthy subjects. We calculated the individual structural volumes of 18 nuclei in the amygdala, and 38 hippocampal subfields using three‐dimensional volumetric T1‐weighted imaging and FreeSurfer program. We also performed an analysis of the intrinsic amygdala‐hippocampal global and local network based on these volumes using a graph theory and Brain Analysis using Graph Theory (BRAPH) program. We investigated the differences in these volumes and network measures between patients with JME and healthy controls.ResultsThere were no significant volume differences in the nuclei of the amygdala and hippocampal subfields between patients with JME and healthy controls. However, we found significant differences in the global network between patients with JME and healthy controls. The mean clustering coefficient was significantly decreased in patients with JME compared to healthy controls (0.473 vs. 0.653, p = .047). In addition, specific regions in the hippocampal subfields showed significant differences in the local network between the two groups. The betweenness centrality of the right CA1‐head, right hippocampus–amygdala‐transition area, left hippocampal fissure, left fimbria, and left CA3‐head, was increased in patients with JME compared to healthy controls.ConclusionThe intrinsic amygdala‐hippocampal global and local networks differed in patients with JME compared to healthy controls, which may be related to the pathogenesis of JME, and memory dysfunction in patients with JME.

Applicability of tactile memory examination as an option to visual- and verbal-based batteries

ABSTRACTThe validity and applicability of tactile battery tests for the diagnosis and medical follow-up of patients with Alzheimer’s disease and other dementia syndromes do not have their usefulness well understood in clinical practice. While haptic abilities in older individuals receive less attention, in earlier stages of human life they are well focused on. There are even fewer studies on tactile memory, including episodic memory of demented individuals with or without sensorial limitations. The applicability of a new haptic memory battery was evaluated in patients with Alzheimer’s disease with mild or moderate commitment.Objective:The aim of this study is to apply a battery based on tactile perception, recognition, and recollection of everyday objects in patients with Alzheimer’s disease, testing tactile delayed recall memory discrimination and late recognition to compare validated visual and verbal tests.Methods:Tactile-, visual-, and verbal-based memory performance was registered in 21 patients diagnosed with Alzheimer’s disease.Results:Except for tactile identification, it showed that there was a close relationship between the three sensory modalities of memory, with an apparent better performance of tactile incidental memory and recognition compared with the test with pictures.Conclusions:The haptic evaluation of memory demonstrated applicability in the evaluation of memory dysfunction in patients with Alzheimer’s disease. Further studies are needed to establish the sensibility and specificity of the proposed test that had a small sample size and many limitations.

Prevalence and factors of verbal learning and memory dysfunction in patients with epilepsy – A single centre study

The objective of this study is to determine prevalence and factors leading to verbal learning and memory dysfunction among patients with epilepsy.A total of 211 subjects were recruited. Their verbal memory was assessed by Rey’s Auditory Verbal Learning Test (RAVLT). This test was further subdivided into four major spheres for analysis, namely the verbal learning, interference list, immediate memory and delayed memory. All data collected were analyzed using Statistical Package for Social Sciences.Among the 211 patients, 55% (n = 116) had focal seizures and the remaining 45% (n = 95) had generalized seizures. Prevalence of verbal learning and memory impairment was high at 39.97% overall, and found most commonly in patients with focal impaired awareness seizures. Verbal learning and immediate memory dysfunction were significantly lower in focal impaired awareness group compared to others. Age more than 50 years, exposure to three or more antiepileptic drugs and use of carbamazepine more than 1000 mg a day were the predictors in poor verbal memory outcome. No statistical difference was observed in the mean RAVLT scores among the gender and hand dominance groups. Between patients with and without electroencephalogram changes as well as brain magnetic resonance imaging changes, the mean RAVLT scores showed no statistically significant difference.Verbal learning and memory impairment is prevalent among the epilepsy patients. The consequences of the memory impairment can be as debilitating as the seizure control. RAVLT is a reliable and practical test in the clinical setting.

Prevalence and Factors Influencing Visual Memory Dysfunction among Epilepsy Patients-A Single-Center Study.

Epilepsy is associated with cognitive impairment due to the disease itself or side-effects of antiepileptic drugs. We aimed to study the prevalence of visual memory dysfunction among epilepsy patients and identify the predictors that could contribute to the impairment. This was a cross-sectional study. We analyzed 250 patients with epilepsy from neurology clinic at our tertiary center. Assessment of visual memory was done using Wechsler Memory Scale-IV (WMS-IV) with scores from subsets of visual reproduction I, II and designs I, II contributing to visual memory index (VMI) score. The correlation between continuous variables was analyzed using Pearson correlation; whereas the VMI scores of different factors were analyzed via a 1-way ANOVA test. The statistical significance was set at P < 0.05. The prevalence of visual memory dysfunction in our epilepsy population was 37.2%. Analysis of individual predictors showed that older patients, lower educational level, combined generalized and focal types of epilepsy, longer duration of epilepsy, greater number of antiepileptic drugs (AEDs) used, and abnormal neuroimaging contributed to poor visual memory. Multiple logistic regression analysis showed that educational level, types of epilepsy, and the number of AEDs used were significant predictors for visual memory impairment. Visual memory dysfunction in patients with epilepsy was due to manifold confounding factors. Our findings enabled us to identify patients with visual memory dysfunction and modifiable factors that contribute to it. WMS-IV is a suitable assessment tool to determine visual memory function, which can help clinicians to optimize the patients' treatment.

Memory Deficits in Obsessive-Compulsive Disorder-Changes over the Course of Cognitive-Behaviour Therapy

A large body of studies demonstrates memory dysfunction in patients with Obsessive-Compulsive Disorder (OCD). Few trials have only equivocally investigated whether this cognitive dysfunction can be improved by treatment. This study aimed to examine the effect of Cognitive-Behaviour Therapy (CBT) on symptom severity and on verbal and non-verbal memory deficits in patients with OCD as an adjunct to pharmacotherapy. Thirty-five OCD patients were compared with thirty-two controls, matched on age, education and diagnosis, on Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) measuring severity of OCD and Auditory Verbal Learning Test (AVLT) and Complex Figure Test (CFT) assessing the verbal and non-verbal memory respectively at the pre-, middle- and post-treatment assessment.OCD patients showed significantly reduced symptoms after completion of their CBT sessions and their memory dysfunctions also ameliorated in the course of treatment. This study indicates that CBT is an effective treatment with those patients who exhibited significant memory deficits and who were severely affected at the beginning of treatment.

Transcranial magnetic stimulation of the precuneus enhances memory and neural activity in prodromal Alzheimer's disease

Memory loss is one of the first symptoms of typical Alzheimer's disease (AD), for which there are no effective therapies available. The precuneus (PC) has been recently emphasized as a key area for the memory impairment observed in early AD, likely due to disconnection mechanisms within large-scale networks such as the default mode network (DMN). Using a multimodal approach we investigated in a two-week, randomized, sham-controlled, double-blinded trial the effects of high-frequency repetitive transcranial magnetic stimulation (rTMS) of the PC on cognition, as measured by the Alzheimer Disease Cooperative Study Preclinical Alzheimer Cognitive Composite in 14 patients with early AD (7 females). TMS combined with electroencephalography (TMS-EEG) was used to detect changes in brain connectivity. We found that rTMS of the PC induced a selective improvement in episodic memory, but not in other cognitive domains. Analysis of TMS-EEG signal revealed an increase of neural activity in patients' PC, an enhancement of brain oscillations in the beta band and a modification of functional connections between the PC and medial frontal areas within the DMN.Our findings show that high-frequency rTMS of the PC is a promising, non-invasive treatment for memory dysfunction in patients at early stages of AD. This clinical improvement is accompanied by modulation of brain connectivity, consistently with the pathophysiological model of brain disconnection in AD.

Altered network efficiency of functional brain networks in patients with breast cancer after chemotherapy.

ObjectiveTo investigate the topological organization of functional brain networks in chemotherapy-treated breast cancer (BC) patients with source memory impairment.MethodsTwenty-eight patients with BCfollowingchemotherapyand40age-and education-matched healthy controls (HCs) were recruited in the current study. All participants underwent source memory tests and resting-state functional MRI scans. Individual whole-brain functional brain networks were constructed and analyzed using graph-based network approaches.ResultsCompared with the HCs, the BC patients showed lower scores in the source memory tests (P < 0.001).Graph-based analyses revealed that the patients showed higher absolute global and local efficiency (both P < 0.01) but lower normalized global and normalized local efficiency (both P< 0.001) compared with the HCs. Locally, several prefrontal, occipital, and parietal regions exhibited higher nodal efficiency and functional connectivity in the patients(P< 0.05, corrected). Finally, positive correlations were observed between normalized global efficiency and Mini-Mental State Examination scores (r = 0.398, P = 0.036) and between normalized local efficiency and the source memory scores (r = 0.497, P = 0.01) in the patients.ConclusionChemotherapy-treated BC is associated with abnormal organization of large-scale functional brain networks, which could account for source memory dysfunction in patients with BC.

Pattern separation performance is decreased in patients with early multiple sclerosis.

BackgroundHippocampal‐dependent memory impairment is frequent and occurs early during the course of multiple sclerosis (MS). While mechanisms responsible for episodic memory dysfunction in patients with MS remain largely unknown, dentate gyrus structure has been suggested as particularly vulnerable at the early stage of the disease. If true, we hypothesized that the pattern separation component of episodic memory (a function known to be critically dependent to dentate gyrus function) would be impaired in patients with early MS (PweMS).MethodsThirty eight participants (19 PweMS and 19 healthy controls matched on age, gender and education level) were tested with a behavioral pattern separation task and also for information processing speed and visuospatial episodic memory.ResultsWe report a significant decrease in pattern separation performance in PweMS compared to healthy controls (27.07 vs. 40.01, p = .030 after Holm–Bonferroni correction, d = 1.02) together with a significantly higher pattern completion rate (56.11 vs. 40.95, p = .004 after Holm–Bonferroni correction, d = 1.07) while no difference was found among groups for information processing speed and “global” visuospatial episodic memory regarding learning, long‐term recall or recognition.ConclusionOur results suggest that behavioral pattern separation task can detect subtle memory decline in patients with MS and argue for early dentate gyrus dysfunction during the course of the disease.

Increased miR-132 level is associated with visual memory dysfunction in patients with depression.

BackgroundImpaired visual memory seems to be a core feature of depression, while increased microRNA-132 (miR-132) levels have been widely reported in depression patients. The authors aimed to explore the relationship between miR-132 changes and visual memory deficits in unmedicated patients with major depressive disorder (MDD).Patients and methodsA total of 62 medication-free MDD patients and 73 matched healthy controls (HCs) were tested for miR-132 expression level in peripheral blood using quantitative real-time polymerase chain reaction. We used a computerized neurocognitive task from the Cambridge Neuropsychological Test Automated Battery (CANTAB) – pattern recognition memory (PRM) task – as a measurement of visual memory. The relationship between visual memory, miR-132 expression level, and clinical symptoms was explored in patients with MDD.ResultsUpregulated miR-132 expression levels were seen in MDD patients but not in HCs. Two-sample t-tests showed that MDD patients had decreased visual memory, mainly memory delayed compared to that of HCs. Correlation analyses revealed that in MDD patients, increased miR-132 expression levels were significantly correlated with visual memory as measured by the CANTABPRM. Hamilton Rating Scale for Anxiety scores were negatively correlated with PRM – number correct (immediate) and PRM – percent correct (immediate).LimitationsThe main limitations were missing data and lack of follow-up studies.ConclusionOur study suggests that increased miR-132 expression levels were associated with visual memory deficits, which may underlie the pathophysiology of MDD. In individuals with depression, immediate visual memory defects were positively correlated with anxiety symptoms.

Mechanisms of memory impairment in epilepsy depend on age at disease onset.

In this study, we aimed to uncover distinct antecedents of autobiographic memory dysfunction in patients with epilepsy with early (childhood/adolescence) vs late (adulthood) disease onset. One hundred sixty-six adults participated: 92 patients with focal epilepsy, whose cognitive and psychiatric functioning were compared to that of 74 healthy controls. Predictors of autobiographic memory deficit were contrasted between patients with early-onset (n = 47) vs late-onset (n = 45) epilepsy. Overall, people with epilepsy performed significantly worse on measures of both semantic and episodic autobiographic memory and showed markedly high rates of depressive symptoms and disorders (p < 0.001). Reduced autobiographic memory in patients with early-onset epilepsy was associated with young age at onset, more frequent seizures, and reduced working memory. In contrast, the difficulty that patients with late-onset epilepsy had in recalling autobiographic information was linked to depression and the presence of an MRI-identified lesion. This study reveals that memory deficits in people with focal epilepsy have differing antecedents depending on the timing of the disease onset. While neurobiological factors strongly underpin reduced autobiographic function in patients with early-onset epilepsy, psychological maladjustment gives rise to the impairments seen in patients with late-onset epilepsy. More broadly, these findings support the practice of subtyping patients according to distinct clinical characteristics to find individualized predictors of cognitive dysfunction.

Abnormalities in gray and white matter volumes associated with explicit memory dysfunction in patients with generalized anxiety disorder.

Background The neuroanatomical abnormalities associated with behavioral dysfunction on explicit memory in patients generalized anxiety disorder (GAD) have not yet been clearly identified. Purpose To investigate the regional gray matter (GM) and white matter (WM) volume alterations over the whole brain in patients with GAD, as well as the correlation between the brain structural abnormality and explicit memory dysfunction. Material and Methods Twenty patients with GAD and 20 healthy controls matched for age, sex, and education level underwent high-resolution T1-weighted magnetic resonance imaging (MRI). The participants performed the explicit memory tasks with the neutral and anxiety-inducing words. Results Patients with GAD showed significantly reduced GM volumes in the midbrain (MB), thalamus, hippocampus (Hip), insula, and superior temporal gyrus (STG); and reduced WM volumes in the MB, anterior limb of the internal capsule (ALIC), dorsolateral prefrontal cortex (DLPFC), and precentral gyrus (PrG). It is important to note that the GM volume of the Hip and the WM volume of the DLPFC were positively correlated with the recognition accuracy (%) in the explicit memory tasks with neutral and anxiety-inducing words, respectively. On the other hand, the WM volume of the PrG was negatively correlated with the reaction time in the same memory tasks. Conclusion This study demonstrated the regional volume changes on whole-brain GM and WM and the correlation between the brain structural alteration and explicit memory dysfunction in GAD patients. These findings would be helpful to understand the association between the brain structure abnormality and the functional deficit in the explicit memory in GAD.

Functional and morphological alterations associated with working memory dysfunction in patients with generalized anxiety disorder

Background Generalized anxiety disorder (GAD) has been related to functional brain activities and structural brain abnormalities. Purpose To investigate the neural mechanism on working memory dysfunction in patients with GAD in terms of the combined functional and morphological brain abnormalities. Material and Methods Patients with GAD and healthy controls matched for age, sex, and education level underwent high-resolution T1-weighted (T1W) magnetic resonance imaging (MRI) and functional MRI (fMRI). In this study, fMRI and voxel-based morphometry (VBM) were used for assessing the differential brain activation patterns, as well as for comparing the morphological alterations between the two groups. Results In response to the neutral distractors, the patients showed significantly lower activities in the regions of the fusiform gyrus (FuG), superior parietal gyrus (SPG), precuneus (PCu), superior occipital gyrus (SOG), lingual gyrus (LiG), cuneus (Cun), calcarine cortex (CaC), parahippocampal gyrus (PHG) and cerebellar cortex (Cb) compared to the controls. In response to the anxiety-inducing distractors, the patients showed significantly higher activity in the hippocampus and lower activities in the regions of the dorsolateral prefrontal cortex (DLPFC), FuG, SPG, PCu, SOG, and Cb. Also, the patients showed a significant reduction of the white matter volumes in the DLPFC, anterior limb of the internal capsule (ALIC) and midbrain. Conclusion This study provides the first evidence for the association between the morphometric alterations and functional deficit in the working memory processing with the neutral and anxiety-inducing distractors in GAD patients. These findings would be helpful to understand the neural mechanisms on working memory impairment in connection with GAD symptoms.

Effects of white matter microstructure lesions on language and memory function in magnetic resonance imaging-negative temporal lobe epilepsy determined by diffusion tensor imaging.

This study was conducted to investigate the associations between white matter lesions and language and memory dysfunctions in patients with magnetic resonance imaging (MRI)-negative temporal lobe epilepsy. This study included 26 patients with temporal lobe epilepsy, who did not have significant findings on conventional MRI scanning, and 17 healthy subjects as control. Diffusion tensor imaging data was obtained with a 3Tesla (T) MRI scanner. Neuropsychological scores of language and memory functions were measured. One-way analysis of variance was used to analyze abnormal fractional anisotropy and mean diffusivity values. Correlations were performed to evaluate the relationship between fractional anisotropy/mean diffusivity of each fiber tract and neuropsychological measures. Regression analysis was performed to determine the contribution of each fiber tract to cognitive performance. Our data showed significantly decreased neuropsychological scores in the left and right temporal lobe epilepsy groups compared with control; it however, failed to show a statistical difference between the two groups. For the left temporal lobe epilepsy group, the mean diffusivity of the left parahippocampal and cingulate cortex, right arcuate fasciculus, and left fornix were significantly higher than control. Fractional anisotropy of the right fornix and mean diffusivity of the left uncinate fasciculus were significantly related to confrontational naming scores. There were significant correlations between the fractional anisotropy of the left fornix and verbal delayed memory scores and between the fractional anisotropy of the left fornix and nonverbal delayed memory scores. The mean diffusivity of left fractional anisotropy and the fractional anisotropy of the left uncinate fasciculus were significantly related to confrontational naming and verbal fluency scores, and seizure frequency was significantly related to nonverbal delayed memory scores. Language and memory function impairment was correlated with white matter structural integrity.

Exploring the efficacy of a 5-day course of transcranial direct current stimulation (TDCS) on depression and memory function in patients with well-controlled temporal lobe epilepsy.

Depression and memory dysfunction significantly impact the quality of life of patients with epilepsy. Current therapies for these cognitive and psychiatric comorbidities are limited. We explored the efficacy and safety of transcranial direct current stimulation (TDCS) for treating depression and memory dysfunction in patients with temporal lobe epilepsy (TLE). Thirty-seven (37) adults with well-controlled TLE were enrolled in a double-blinded, sham-controlled, randomized, parallel-group study of 5 days of fixed-dose (2 mA, 20 min) TDCS. Subjects were randomized to receive either real or sham TDCS, both delivered over the left dorsolateral prefrontal cortex. Patients received neuropsychological testing and a 20-minute scalp EEG at baseline immediately after the TDCS course and at 2- and 4-week follow-up. There was improvement in depression scores immediately after real TDCS, but not sham TDCS, as measured by changes in the Beck Depression Inventory (BDI change: -1.68 vs. 1.27, p<0.05) and NDDI-E (-0.83 vs. 0.9091, p=0.05). There was no difference between the groups at the 2- or 4-week follow-up. There was no effect on delayed or working memory performance. Transcranial direct current stimulation was well-tolerated and did not increase seizure frequency or interictal discharge frequency. Transcranial direct current stimulation induced an increase in delta frequency band power over the frontal region and delta, alpha, and theta band power in the occipital region after real stimulation compared to sham stimulation, although the difference did not reach statistical significance. This study provides evidence for the use of TDCS as a safe and well-tolerated nonpharmacologic approach to improving depressive symptoms in patients with well-controlled TLE. However, there were no changes in memory function immediately following or persisting after a stimulation course. Further studies may determine optimal stimulation parameters for maximal mood benefit.

Memory for gist and detail information in patients with Parkinson's disease

ObjectiveMemory formation is proposed to be a dual process that involves the simultaneous memorisation of both detailed information (item-specific memory) and gist information (gist memory). Memory deficits have been reported...