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To understand the neurocognitive mechanisms that underlie heterogeneity in cognitive ageing, recent scientific efforts have led to a growing public availability of imaging cohort data. The Advanced BRain Imaging on ageing and Memory (ABRIM) project aims to add to these existing datasets by taking an adult lifespan approach to provide a cross-sectional, normative database with a particular focus on connectivity, myelinization and iron content of the brain in concurrence with cognitive functioning, mechanisms of reserve, and sleep-wake rhythms. ABRIM freely shares MRI and behavioural data from 295 participants between 18–80 years, stratified by age decade and sex (median age 52, IQR 36–66, 53.20% females). The ABRIM MRI collection consists of both the raw and pre-processed structural and functional MRI data to facilitate data usage among both expert and non-expert users. The ABRIM behavioural collection includes measures of cognitive functioning (i.e., global cognition, processing speed, executive functions, and memory), proxy measures of cognitive reserve (e.g., educational attainment, verbal intelligence, and occupational complexity), and various self-reported questionnaires (e.g., on depressive symptoms, pain, and the use of memory strategies in daily life and during a memory task). In a sub-sample (n = 120), we recorded sleep-wake rhythms using an actigraphy device (Actiwatch 2, Philips Respironics) for a period of 7 consecutive days. Here, we provide an in-depth description of our study protocol, pre-processing pipelines, and data availability. ABRIM provides a cross-sectional database on healthy participants throughout the adult lifespan, including numerous parameters relevant to improve our understanding of cognitive ageing. Therefore, ABRIM enables researchers to model the advanced imaging parameters and cognitive topologies as a function of age, identify the normal range of values of such parameters, and to further investigate the diverse mechanisms of reserve and resilience. [ABSTRACT FROM AUTHOR]

Purpose: We propose a novel RF pulse providing an adiabatic null passage (ANP) for magnetization transfer preparation with improved insensitivity to B1+$$ {\mathrm{B}}_1^{+} $$ and B0 inhomogeneities and mitigated direct saturation and T2 effects. Method: The phase modulation function of a 6‐ms time‐resampled frequency offset–corrected pulse was modified to achieve zero flip angle at the end of the pulse. The spectral response was simulated, and its insensitivity to B0 and B1+$$ {\mathrm{B}}_1^{+} $$ was investigated and compared with a phase‐inverted (12¯$$ \overline{2} $$1‐1¯$$ \overline{1} $$21¯$$ \overline{1} $$) binomial pulse. The proposed pulse was implemented in a 2D‐EPI pulse sequence to generate magnetization transfer (MT) contrast and MT ratio (MTR) maps. In vivo experiments were performed on 3 healthy participants with power‐matched settings for ANP and the binomial pulse with the following parameters: 6‐ms binomial pulse with a flip angle of 107° (shortest element) and pulse repetition period (PRP) of TRslice = 59 ms, three experiments with 6‐ms ANP and constant MT used overdrive factor (OF)/PRP values of 1/TRslice, 2$$ \sqrt{2} $$/2TRslice, and 3$$ \sqrt{3} $$/3TRslice. Results: At gray matter (white matter) in vivo, the MTR decreased from 61% (64%) at OF = 1 to 38% (42%) applying ANP with an OF = 3$$ \sqrt{\mathsf{3}} $$ and PRP = 3 TRslice, demonstrating the mitigation of T2/direct effect by 22% (22%). Bloch‐McConnell simulations gave similar values. In vivo experiments showed significant improvement in the MTR values for areas with high B0 inhomogeneity. Conclusion: ANP pulse was shown to be advantageous over its binomial counterpart in providing MT contrast by mitigating the T2 effect and direct saturation of the liquid pool as well as reduced sensitivity to B1+$$ {\mathrm{B}}_1^{+} $$ and B0 inhomogeneity. [ABSTRACT FROM AUTHOR]

Background To investigate whether structural network disconnectivity is associated with parkinsonian signs and their progression, as well as with an increased risk of incident parkinsonism. Methods In a prospective cohort (Radboud University Nijmegen Diffusion Tensor and Magnetic Resonance Cohort study) consisting of 293 participants with small vessel disease (SVD), we assessed parkinsonian signs and incident parkinsonism over an 8-year follow-up. In addition, we reconstructed the white matter network followed by graph-theoretical analyses to compute the network metrics. Conventional magnetic resonance imaging markers for SVD were assessed. Results We included 293 patients free of parkinsonism at baseline (2011), with a mean age 68.8 (standard deviation [ SD ] 8.4) years, and 130 (44.4%) were men. Nineteen participants (6.5%) developed parkinsonism during a median (SD) follow-up time of 8.3 years. Compared with participants without parkinsonism, those with all-cause parkinsonism had higher Unified Parkinson's Disease Rating scale (UPDRS) scores and lower global efficiency at baseline. Baseline global efficiency was associated with UPDRS motor scores in 2011 (β = −0.047, p  < .001) and 2015 (β = −0.84, p  < .001), as well as with the changes in UPDRS scores during the 4-year follow-up (β = −0.63, p  = .004). In addition, at the regional level, we identified an inter-hemispheric disconnected network associated with an increased UPDRS motor score. Besides, lower global efficiency was associated with an increased risk of all-cause and vascular parkinsonism independent of SVD markers. Conclusions Our findings suggest that global network efficiency is associated with a gradual decline in motor performance, ultimately leading to incident parkinsonism in the elderly with SVD. Global network efficiency may have the added value to serve as a useful marker to capture changes in motor signs. [ABSTRACT FROM AUTHOR]

Objective: Postictal symptoms may result from cerebral hypoperfusion, which is possibly a consequence of seizure‐induced vasoconstriction. Longer seizures have previously been shown to cause more severe postictal hypoperfusion in rats and epilepsy patients. We studied cerebral perfusion after generalized seizures elicited by electroconvulsive therapy (ECT) and its relation to seizure duration. Methods: Patients with a major depressive episode who underwent ECT were included. During treatment, 21‐channel continuous electroencephalogram (EEG) was recorded. Arterial spin labeling magnetic resonance imaging scans were acquired before the ECT course (baseline) and approximately 1 h after an ECT‐induced seizure (postictal) to quantify global and regional gray matter cerebral blood flow (CBF). Seizure duration was assessed from the period of epileptiform discharges on the EEG. Healthy controls were scanned twice to assess test–retest variability. We performed hypothesis‐driven Bayesian analyses to study the relation between global and regional perfusion changes and seizure duration. Results: Twenty‐four patients and 27 healthy controls were included. Changes in postictal global and regional CBF were correlated with seizure duration. In patients with longer seizure durations, global decrease in CBF reached values up to 28 mL/100 g/min. Regional reductions in CBF were most prominent in the inferior frontal gyrus, cingulate gyrus, and insula (up to 35 mL/100 g/min). In patients with shorter seizures, global and regional perfusion increased (up to 20 mL/100 g/min). These perfusion changes were larger than changes observed in healthy controls, with a maximum median global CBF increase of 12 mL/100 g/min and a maximum median global CBF decrease of 20 mL/100 g/min. Significance: Seizure duration is a key factor determining postictal perfusion changes. In future studies, seizure duration needs to be considered as a confounding factor due to its opposite effect on postictal perfusion. [ABSTRACT FROM AUTHOR]

Previous studies have identified several brain regions that appear to be involved in the acquisition of novel word forms. Standard word-by-word presentation is often used although exposure to a new language normally occurs in a natural, real world situation. In the current experiment we investigated naturalistic language exposure and applied a model-free analysis for hemodynamic-response data. Functional connectivity, temporal correlations between hemodynamic activity of different areas, was assessed during rest before and after presentation of a movie of a weather report in Mandarin Chinese to Dutch participants. We hypothesized that learning of novel words might be associated with stronger functional connectivity of regions that are involved in phonological processing. Participants were divided into two groups, learners and non-learners, based on the scores on a post hoc word recognition task. The learners were able to recognize Chinese target words from the weather report, while the non-learners were not. In the first resting state period, before presentation of the movie, stronger functional connectivity was observed for the learners compared to the non-learners between the left supplementary motor area and the left precentral gyrus as well as the left insula and the left rolandic operculum, regions that are important for phonological rehearsal. After exposure to the weather report, functional connectivity between the left and right supramarginal gyrus was stronger for learners than for non-learners. This is consistent with a role of the left supramarginal gyrus in the storage of phonological forms. These results suggest both pre-existing and learning-induced differences between the two groups. (Contains 1 table and 2 figures.)