Interaction between cognitive reserve and age moderates effect of lesion load on stroke outcome.

The concepts of brain reserve and cognitive reserve were recently suggested as valuable predictors of stroke outcome. To test this hypothesis, we used age, years of education and lesion size as clinically feasible coarse proxies of brain reserve, cognitive reserve, and the extent of stroke pathology correspondingly. Linear and logistic regression models were used to predict cognitive outcome (Montreal Cognitive Assessment) and stroke-induced impairment and disability (NIH Stroke Scale; modified Rankin Score) in a sample of 104 chronic stroke patients carefully controlled for potential confounds.

The rostro-caudal gradient in the prefrontal cortex and its modulation by subthalamic deep brain stimulation in Parkinson's disease.

Deep brain stimulation of the subthalamic nucleus (STN-DBS) alleviates motor symptoms in Parkinson's disease (PD) but also affects the prefrontal cortex (PFC), potentially leading to cognitive side effects. The present study tested alterations within the rostro-caudal hierarchy of neural processing in the PFC induced by STN-DBS in PD. Granger-causality analyses of fast functional near-infrared spectroscopy (fNIRS) measurements were used to infer directed functional connectivity from intrinsic PFC activity in 24 PD patients treated with STN-DBS.

Determinants of Inter-Individual Variability in Corticomotor Excitability Induced by Paired Associative Stimulation.

Transcranial magnetic stimulation (TMS) is a well-established tool in probing cortical plasticity . Changes in corticomotor excitability can be induced using paired associative stimulation (PAS) protocol, in which TMS over the primary motor cortex is conditioned with an electrical peripheral nerve stimulation of the contralateral hand. PAS with an inter-stimulus interval of 25 ms induces long-term potentiation (LTP)-like effects in cortical excitability.

Psychometric analyses of the Tower of London planning task reveal high reliability and feasibility in typically developing children and child patients with ASD and ADHD.

The Tower of London (TOL) is probably the most often used assessment tool for planning ability in healthy and clinical samples. Various versions, including our proposed standard problem set, have proven to be feasible and reliable in adults. In contrast, reliability information for typically developing (TD) children and neurodevelopmental disorders during childhood are largely missing.

Dissociation among preserved resistance to proactive interference and impaired behavioral inhibition in a patient with bilateral lesions in the inferior frontal gyrus: A single-case study.

Inhibition is not a unitary construct, as different inhibition-related functions have been disentangled. The present single-case study compares performance of a patient with bilateral lesions in the inferior frontal gyrus (IFG) and anterior insula to healthy age-matched controls in different inhibition-related tasks. Particular focus was on the resolution of proactive interference that is supposed to rely on bilateral IFG and anterior insula.

Data on the test-retest reproducibility of streamline counts as a measure of structural connectivity.

These data provide estimations of test-retest reproducibility of streamline counts based on diffusion weighted imaging (DWI) data using a global tractography algorithm in a sample of young healthy adults. Data on descriptive statistics and factorial analyses of within-session and between-session reproducibility in terms of intra-class correlation coefficients for the absolute agreement between measurements are provided. The effect of several exemplary methodological parameters pertaining to different steps along the tractography processing pipeline on reproducibility are considered.

The anatomy of the human medial forebrain bundle: Ventral tegmental area connections to reward-associated subcortical and frontal lobe regions.

Introduction: Despite their importance in reward, motivation, and learning there is only sparse anatomical knowledge about the human medial forebrain bundle (MFB) and the connectivity of the ventral tegmental area (VTA). A thorough anatomical and microstructural description of the reward related PFC/OFC regions and their connection to the VTA - the superolateral branch of the MFB (slMFB) - is however mandatory to enable an interpretation of distinct therapeutic effects from different interventional treatment modalities in neuropsychiatric disorders (DBS, TMS etc.).

Brain Aging and APOE ε4 Interact to Reveal Potential Neuronal Compensation in Healthy Older Adults.

Compensation implies the recruitment of additional neuronal resources to prevent the detrimental effect of age-related neuronal decline on cognition. Recently suggested statistical models comprise behavioral performance, brain activation, and measures related to aging- or disease-specific pathological burden to characterize compensation. Higher chronological age as well as the APOE ε4 allele are risk factors for Alzheimer's disease.

Probing the reproducibility of quantitative estimates of structural connectivity derived from global tractography.

As quantitative measures derived from fiber tractography are increasingly being used to characterize the structural connectivity of the brain, it is important to establish their reproducibility. However, no such information is as yet available for global tractography. Here we provide the first comprehensive analysis of the reproducibility of streamline counts derived from global tractography as quantitative estimates of structural connectivity.

Real-world navigation in amnestic mild cognitive impairment: The relation to visuospatial memory and volume of hippocampal subregions.

Spatial disorientation is a frequent symptom in Alzheimer's disease and in mild cognitive impairment (MCI). In the clinical routine, spatial orientation is less often tested with real-world navigation but rather with 2D visuoconstructive tasks. However, reports about the association between the two types of tasks are sparse.

Biological Factors Contributing to the Response to Cognitive Training in Mild Cognitive Impairment.

In mild cognitive impairment (MCI), small benefits from cognitive training were observed for memory functions but there appears to be great variability in the response to treatment. Our study aimed to improve the characterization and selection of those participants who will benefit from cognitive intervention. We evaluated the predictive value of disease-specific biological factors for the outcome after cognitive training in MCI (n = 25) and also considered motivation of the participants.

APOE moderates compensatory recruitment of neuronal resources during working memory processing in healthy older adults.

The APOE ε4 allele increases the risk for sporadic Alzheimer's disease and modifies brain activation patterns of numerous cognitive domains. We assessed cognitively intact older adults with a letter n-back task to determine if previously observed increases in ε4 carriers' working-memory-related brain activation are compensatory such that they serve to maintain working memory function. Using multiple regression models, we identified interactions of APOE variant and age in bilateral hippocampus independently from task performance: ε4 carriers only showed a decrease in activation with increasing age, suggesting high sensitivity of fMRI data for detecting changes in Alzheimer's disease-relevant brain areas before cognitive decline.

Are semantic and phonological fluency based on the same or distinct sets of cognitive processes? Insights from factor analyses in healthy adults and stroke patients.

Verbal fluency for semantic categories and phonological letters is frequently applied to studies of language and executive functions. Despite its popularity, it is still debated whether measures of semantic and phonological fluency reflect the same or distinct sets of cognitive processes. Word generation in the two task variants is believed to involve different types of search processes.