Decreased Event-Related Beta Synchronization During Memory Maintenance Marks Early Cognitive Decline in Mild Cognitive Impairment.

Mild cognitive impairment (MCI) refers to a measurable deficit in cognition in the absence of dementia or impairment in activities of daily living. Working memory impairment is among the earliest signs of MCI. Oscillatory analysis of working memory might be a potential tool for identifying patients at increased risk of developing dementia. Our study aimed to assess the temporospatial pattern of spectral differences during working memory maintenance between MCI patients and healthy controls and to compare the sources of oscillatory activity between the two groups. Event-related spectral perturbation of 17 MCI patients and 21 healthy control participants was studied with 128-channel EEG during the Sternberg working memory task. Source localization was performed by using the eLORETA software. Among the participants, 13 MCI and 15 control participants underwent a structural brain MRI examination. Event-related synchronization (ERS) in the alpha and beta frequency band was significantly lower in MCI patients compared to healthy control participants during retention. Both study groups showed significant memory load-related enhancement in both frequency band. In the MCI group, source localization revealed significantly attenuated beta oscillatory activity in the inferior and middle temporal gyrus, in the fusiform gyrus, and in the cuneus. Beta ERS correlated significantly with the size of the hippocampus, entorhinal cortex, and parahippocampal gyrus. During the retention period, MCI is characterized by decreased alpha and beta ERS compared to controls indicating early impairment in neural networks serving working memory maintenance. The assessment of electrophysiological changes in the beta frequency range may provide a useful diagnostic tool for the early detection of cognitive impairment.

What can DTI tell about early cognitive impairment? - Differentiation between MCI subtypes and healthy controls by diffusion tensor imaging.

Mild cognitive impairment (MCI) gained a lot of interest recently, especially that the conversion rate to Alzheimer Disease (AD) in the amnestic subtype (aMCI) is higher than in the non-amnestic subtype (naMCI). We aimed to determine whether and how diffusion-weighted MRI (DWI) using the diffusion tensor model (DTI) can differentiate MCI subtypes from healthy subjects. High resolution 3D T1W and DWI images of patients (aMCI, n = 18; naMCI, n = 20; according to Petersen criteria) and controls (n = 27) were acquired at 3T and processed using ExploreDTI and SPM. Voxel-wise and region of interest (ROI) analyses of fractional anisotropy (FA) and mean diffusivity (MD) were performed with ANCOVA; MD was higher in aMCI compared to controls or naMCI in several grey and white matter (GM, WM) regions (especially in the temporal pole and the inferior temporal lobes), while FA was lower in WM ROI-s (e.g. left Cingulum). Moreover, significant correlations were identified between verbal fluency, visual and verbal memory performance and DTI metrics. Logistic regression showed that measuring FA of the crus of fornix along GM volumetry improves the discrimination of aMCI from naMCI. Additional information from DWI/DTI aids preclinical detection of AD and may help detecting early non-Alzheimer type dementia, too.

The Differentiation of Amnestic Type MCI from the Non-Amnestic Types by Structural MRI.

INTRODUCTION: While amnestic mild cognitive impairment (aMCI) and non-amnestic mild cognitive impairment (naMCI) are theoretically different entities, only a few investigations studied the structural brain differences between these subtypes of mild cognitive impairment. The aim of the study was to find the structural differences between aMCI and naMCI, and to replicate previous findings on the differentiation between aMCI and healthy controls. METHODS: Altogether 62 aMCI, naMCI, and healthy control subjects were included into the study based on the Petersen criteria. All patients underwent a routine brain MR examination, and a detailed neuropsychological examination. RESULTS: The sizes of the hippocampus, the entorhinal cortex and the amygdala were decreased in aMCI relative to naMCI and to controls. Furthermore the cortical thickness of the entorhinal cortex, the fusiform gyrus, the precuneus and the isthmus of the cingulate gyrus were significantly decreased in aMCI relative to naMCI and healthy controls. The largest differences relative to controls were detected for the volume of the hippocampus (18% decrease vs. controls) and the cortical thickness (20% decrease vs. controls) of the entorhinal cortex: 1.6 and 1.4 in terms of Cohen's d. Only the volume of the precuneus were decreased in the naMCI group (5% decrease) compared to the control subjects: 0.9 in terms of Cohen's d. Significant between group differences were also found in the neuropsychological test results: a decreased anterograde, retrograde memory, and category fluency performance was detected in the aMCI group relative to controls and naMCI subjects. Subjects with naMCI showed decreased letter fluency relative to controls, while both MCI groups showed decreased executive functioning relative to controls as measured by the Trail Making test part B. Memory performance in the aMCI group and in the entire sample correlated with the thickness of the entorhinal cortex and with the volume of the amygdala. CONCLUSION: The amnestic mild cognitive impairment/non-amnestic mild cognitive impairment separation is not only theoretical but backed by structural imaging methods and neuropsychological tests. A better knowledge of the MCI subtypes can help to predict the direction of progression and create targeted prevention.

Monitoring the early signs of cognitive decline in elderly by computer games: an MRI study.

BACKGROUND: It is anticipated that current and future preventive therapies will likely be more effective in the early stages of dementia, when everyday functioning is not affected. Accordingly the early identification of people at risk is particularly important. In most cases, when subjects visit an expert and are examined using neuropsychological tests, the disease has already been developed. Contrary to this cognitive games are played by healthy, well functioning elderly people, subjects who should be monitored for early signs. Further advantages of cognitive games are their accessibility and their cost-effectiveness. PURPOSE: The aim of the investigation was to show that computer games can help to identify those who are at risk. In order to validate games analysis was completed which measured the correlations between results of the 'Find the Pairs' memory game and the volumes of the temporal brain regions previously found to be good predictors of later cognitive decline. PARTICIPANTS AND METHODS: 34 healthy elderly subjects were enrolled in the study. The volume of the cerebral structures was measured by MRI. Cortical reconstruction and volumetric segmentation were performed by Freesurfer. RESULTS: There was a correlation between the number of attempts and the time required to complete the memory game and the volume of the entorhinal cortex, the temporal pole, and the hippocampus. There was also a correlation between the results of the Paired Associates Learning (PAL) test and the memory game. CONCLUSIONS: The results gathered support the initial hypothesis that healthy elderly subjects achieving lower scores in the memory game have increased level of atrophy in the temporal brain structures and showed a decreased performance in the PAL test. Based on these results it can be concluded that memory games may be useful in early screening for cognitive decline.

[Pharmacological and other options in preventing dementia: a literature review]. / Demenciák megelozésének gyógyszeres és egyéb lehetoségei: irodalmi összefoglaló

BACKGROUND: At present 34 million people live with Alzheimer's disease around the world. This figure is expected to triple in the next 40 years. The major cause of this increase is the well-known aging of the society in Europe and in the US as well. AIMS AND METHODS: In this paper we review the results of the last 10 years, and discuss those pharmaceutical and other methods, which can be effective in the prevention of dementias. RESULTS: The most important pharmaceutical agents are beta secretase inhibitors, and active and passive immunizations. Several drugs in these groups are in phase III at the moment. The results from studies with intranasal insulin are also encouraging. As a non-drug option Mediterranean diet can be effective. However at present cognitive trainings seem to be the most effective in the prevention of dementias. These remediation therapies are based on the lifelong plasticity of the human brain. CONCLUSIONS: In summary we can conclude that there are promising drug developments in progess for the prevention of dementias, but the breakthrough has not been achieved yet. At present the best option is decreasing risk factors, that is treatment of hypertension, prevention of obesity and diabetes, and cognitive trainings are recommended for prevention.

Altered social decision making in borderline personality disorder: an Ultimatum Game study.

The authors examined social decision-making strategies in borderline personality disorder (BPD) using the Ultimatum Game (UG). They sought to extend previous findings by investigating altruistic punishment, a behavior that increases group cooperation in the long term. They tested the effect of the proposer's facial expression on responses. BPD patients (n = 47) and healthy controls (n = 43) played the responder's role in a series of computerized UG interactions, with proposers expressing positive or negative emotions. BPD patients accepted unfair offers at a higher rate compared to controls. The effect of facial expression differed in the two groups, as positive expressions increased the acceptance likelihood in the control group at stakes from 20:80 to 50:50. In the BPD group, this effect was observed only at higher stakes (40:60 and 50:50). These results suggest that BPD patients exhibit altruistic punishment to a lesser extent and are less influenced by their partners' emotional expression in the UG.

[Differentiation between mild cognitive impairment and healthy elderly population using neuropsychological tests]. / Az enyhe kognitív deficitben szenvedok differenciálása az egészséges idos populációtól neuropszichológiai tesztek segítségével.

OBJECTIVE: Paired Associates Learning (PAL) test assesses brain functions in those brain regions affected earliest by Alzheimer's dementia. The aim of the present study was to assess the usability of our implementation of the PAL test for screening mild cognitive impairment. METHODOLOGY: Based on Petersen criteria, 14 out of the 63 subjects were diagnosed with mild cognitive impairment. Visuospatial learning was assessed by our implementation of PAL test. The ability of the PAL test to differentiate between study groups was compared to the Addenbrook Cognitive Examination (ACE) and to the Mini Mental State Examination (MMSE). Linear logistic regression was used for statistical analysis, and the results are presented as Receiver Operating Characteristics (ROC) curves. All analyses were performed by SAS 9.2. RESULTS: All the results of neuropsychological tests differed significantly between the study groups. However, considerable difference could be detected between the tests regarding specificity and sensitivity. The PAL test reached the sensitivity of the ACE, while its specificity was slightly under the ACE. DISCUSSION: The PAL test developed in the framework of the present study is found to be able to differentiate between MCI and healthy controls. It outperformed the MMSE in terms of sensitivity and specificity, while it needs comparable time to perform. Its sensitivity, the important parameter for screening, is comparable to ACE, while it needs significantly shorter time and less assistance.

[Clinical characteristics of 5 hospitalized 3,4-methylenedioxypyrovalerone (MDPV) users]. / A 3,4-methylenedioxypyrovaleron (MDPV) használatával kapcsolatos klinikai tapasztalatok öt hospitalizált paciens esete kapcsán.

A new illegal psychotropic substance appeared in Hungary during the first months of 2011. Acutely hospitalized patients with psychosis disclosed using a new type of designer drug, previously unknown to clinicians. As the new drug became better known, the cases with acute intoxication were often also transported to toxicology departments. In this study we summarize 5 short case studies that demonstrate the heterogeneous symptoms associated with MDPV abuse, and draw attention to the frequently occurring delusions, and the extended risk of intravenous substance use. Present case studies include patients with and without psychiatric history, regular and occasional users, intravenous and other routes of administration. In the short run antipsychotic therapy reduced the symptoms in all cases, but there is no clear therapeutic guideline for the treatment of patients having psychiatric problems associated with these drugs at the present time. The laboratory examination is unresolved as well. Mephedrone, MDPV and recent drugs have drawn attention to the problem of designer drugs again. This article examines the interaction of drug consumption trends and changes in law, apropos of the presented cases. This information can be helpful for the future treatment of MDPV or other designer drug users. Possible research and therapeutic implications are also discussed.