13 Feb

Complex multi-echo fMRI dataset: New strategies in processing of multi-echo data

This publication introduces a novel, publicly available dataset designed to support the development and evaluation of advanced algorithms and processing workflows for complex multi-echo functional magnetic resonance imaging (fMRI) data.

The dataset comprises multi-echo fMRI and electrophysiological recordings collected from 83 healthy, right-handed adult participants.

Data was acquired with two 3 T MR scanners and is available on OpenNeuro under the title "Complex multi-echo fMRI dataset: New strategies in processing of multi-echo data".

13 Feb

Effectiveness of brief semiological training in distinguishing functional/dissociative seizures from epileptic seizures

Objective: Functional/dissociative seizures are seizures that mimic epileptic seizures in their presentation and are often mistaken for them. Clinical recognition of these seizures presents a challenge and misdiagnosis can lead to inappropriate treatment, increasing the risk of complications. To address this, we conducted a study involving 45 young neurology residents from the Czech Republic and Slovakia who had no specialized training in epilepsy or functional neurological disorders. Our goal was to determine whether a brief training in selected semiological features of functional/dissociative seizures (FDS) would efficiently teach them to differentiate between FDS and epileptic seizures (ES) in a clinical setting.

Methods: A set of 10 clinical signs characteristic of FDS was selected based on Evidence-Based Practice for the Clinical Assessment of Psychogenic Nonepileptic Seizures (Baslet et al., 2021). Initially, participants identified epileptic seizures and FDS in 30 video recordings without any prior instruction. Subsequently, they received a 15-minute educational session focused on selected semiological features of FDS. Then the same 30 seizure videos were shown again to assess their recognition abilities. No EEG recordings were shown.

Results: Following this educational intervention, participants' accuracy in distinguishing FDS from ES significantly improved from 77% before training to 89% after training (p < 0.001).

13 Feb

Timing for Starting Antiseizure Medication Withdrawal After Epilepsy Surgery in Adults

Background and objectives: More than half of people undergoing epilepsy surgery become seizure-free and may consider withdrawing antiseizure medications (ASMs). Withdrawal practices vary, and the optimal timing remains unclear. We aim to compare seizure relapse risk among individuals initiating ASM withdrawal at different time points after epilepsy surgery.

Methods: We conducted a multicenter observational cohort study of adults who underwent resective epilepsy surgery between 1990 and 2016 at 12 tertiary centers. Participants were seizure-free before medication withdrawal and had at least 1 year of follow-up. Seizure relapse risk was compared among those initiating withdrawal 1, 2, 3, 4, or 5 years postoperatively vs later. We used propensity score matching for each comparison to adjust for treatment selection bias.

Results: Of the 964 people included (51% female; median age at surgery 34 years [interquartile range 26-44]), 446 (46%) began ASM withdrawal in the first year after surgery, 255 (26%) in the second, 110 (11%) in the third, 58 (6%) in the fourth, 29 (3%) in the fifth, and 66 (7%) after the fifth year. After matching, those starting withdrawal in the first (hazard ratio [HR] 1.4; p = 0.003) or second (HR 1.18; p < 0.001) year had a higher risk of relapse than those who withdrew later. Starting withdrawal in the third (HR 1.7; p = 0.12), fourth (HR 1.3; p = 0.45), or fifth (HR 0.17; p = 0.82) year after surgery showed no increase in risk compared with later withdrawal. 

22 Jan

GLP-1 Receptor Agonists for Secondary Prevention After Myocardial Infarction and Stroke in Type 2 Diabetes: Nationwide Real-World Evidence

Aims: Glucagon-like peptide-1 receptor agonists (GLP-1RA) reduce cardiovascular risk in patients with type 2 diabetes (T2D) and established atherosclerotic cardiovascular disease and are recommended in guidelines. We evaluated the real-world effectiveness of GLP-1RA therapy on cardiovascular outcomes in patients with T2D after myocardial infarction (MI) or ischemic stroke and examined trends and disparities.

Methods: Using nationwide Czech registry data (2015-2024), we identified patients with incident nonfatal MI or ischemic stroke and confirmed T2D. GLP-1RA users-initiating therapy within 12 months post-event-were propensity score-matched to non-users. The primary outcome was major adverse cardiovascular events (MACE: nonfatal MI, nonfatal stroke, cardiovascular death); secondary outcomes included individual components and all-cause mortality.

Results: GLP-1RA therapy was initiated in only ∼2% of MI and stroke survivors with T2D. Among 126,845 MI survivors, 28,206 had T2D; the matched cohort comprised 2,271 patients (401 GLP-1RA; median follow-up 35 months). GLP-1RA use was associated with lower risk of MACE (HR:0.7; 95%CI:0.52-0.93), all-cause (HR:0.61;95%CI:0.47-0.80) and cardiovascular death (HR:0.54, 95%CI:0.36-0.80). Among 177,115 stroke survivors, 73,750 had T2D; the matched cohort comprised 2,235 patients (385 GLP-1RA; median follow-up 27 months). 

22 Jan

The Assessment of RAB32 p.Ser71Arg Variant Prevalence in Parkinson's Disease Across Selected African, European, and South American Cohorts

Monogenic forms of Parkinson's disease (PD) have demonstrated a heterogeneous disorder involving multiple biological pathways.¹ Familial forms of PD have been linked to variants in LRRK2, SNCA, VPS35, PARKIN, and PINK1.¹ Heterozygous GBA mutation carriers are associated with higher disease risk, earlier onset, and accelerated clinical progression.¹

Recently, RAB32 has emerged as a nominated PD gene. It encodes a Rab GTPase involved in mitochondrial and vesicular trafficking pathways. A rare substitution, p.Ser71Arg (rs200251693), has been proposed as a potential susceptibility factor.^2, 3 Reported carriers exhibit late-onset, levodopa-responsive parkinsonism with familial clustering; the only available autopsy case lacked Lewy bodies.^1-3 Across published studies, RAB32 c.213C>G was detected in 0.22% to 2.3% of patients, primarily within Mediterranean and North American cohorts, and was absent in large East Asian datasets. This pattern suggests regional specificity and a possible shared Mediterranean haplotype.^2-6 Limited data exist from several regions, including Eastern Europe, Ireland, sub-Saharan Africa, and South America.

22 Jan

Influence of hypokinetic dysarthria severity level on the long-term outcome of repetitive transcranial magnetic stimulation therapy

Introduction: Hypokinetic dysarthria (HD) is a common and disabling symptom of Parkinson's disease (PD) for which established pharmacological and surgical treatments bring only limited, often short-term improvement in speech. The aim of this study was to investigate whether the long-term acoustic effects of repetitive transcranial magnetic stimulation (rTMS) over the right superior temporal gyrus (STG) depend on the baseline severity of HD.

Methods: 26 PD patients were randomized to active STG-targeted rTMS (n = 15) or sham stimulation (n = 11) and followed across five recording sessions over 14 weeks, alongside one session of matched healthy controls. HD severity at baseline was quantified using 3F test subscores and used to stratify patients into milder (0) and more severe (1) subgroups. The STG 1 subgroup combined greater motor and speech impairment with shorter disease duration. Multiple acoustic features from sustained phonation and free monologue were extracted, normalized to controls, adjusted for sex, and analyzed using non-parametric statistics and descriptive visualisations.

Results: Patients with more severe HD receiving active stimulation (STG 1) showed consistent, long-lasting improvements in phonation-related parameters, whereas milder HD (STG 0) and sham groups (SHAM 0, SHAM 1) exhibited only limited or transient changes.

5 Jan

Network hubs supporting memory encoding: Implications for cognitive preservation in epilepsy surgery

Objective: Memory impairments are common in neurological disorders, especially drug-resistant epilepsy, where cognitive deficits such as accelerated long-term forgetting may occur before surgery due to interictal/ictal discharges, antiseizure medications, and disease progression. Postsurgical memory decline affects 40%-60% of patients. Understanding the neural mechanisms of memory encoding is essential for identifying critical network hubs and guiding surgical interventions that preserve cognitive function.

Methods: We analyzed intracranial electroencephalographic recordings from epilepsy patients (n = 15) performing a verbal memory encoding task to identify key structures involved in successful memory formation. Functional connectivity was computed using multiple features across several frequency bands. Temporal dynamics of connectivity were examined to characterize pre-encoding and encoding phases.

Results: The middle temporal gyrus (MTG) consistently emerged as a verbal memory hub across features and frequency bands. The inferior frontal gyrus (IFG) was identified as a beta-band-specific hub via phase synchrony. Temporal analyses revealed that MTG exhibited stable and widespread connectivity differences across all encoding phases, suggesting a role in pre-encoding network priming. 

5 Jan

Functional Impact Score of Mitochondrial Variants and Its Relationship With Functional Connectivity of the Brain: Potential Origins of Premature Aging in Young Adulthood

Alterations in mitochondrial DNA (mtDNA) have been associated with worse cognitive abilities in older adults and premature epigenetic aging in young adulthood. However, it is not clear how mitochondrial dysfunction affects brain function in young adulthood and whether cognition-related networks might be most affected. We tested whether mtDNA functional impact (FI) score might map onto specific patterns of between-network functional connectivity in young adults from the European Longitudinal Study of Pregnancy and Childhood (ELSPAC). We also tested whether these relationships might be mediated by accelerated epigenetic aging, calculated using Horvath's epigenetic clock, CheekAge clock, and AltumAge clock. General connectivity method was used as a reliable marker of individual differences in brain function. We showed that a greater mtDNA FI score was associated with lower connectivity between the dorsal attention and language networks (beta = -0.41, p = 0.0007, AdjR² = 0.15) and that there was suggestive evidence that this relationship might be mediated by accelerated epigenetic aging calculated using Horvath's epigenetic clock in young adulthood (ab = -0.061, SE = 0.04, 95% CI [-0.163; 0.001], 90% CI [-0.142; -0.002]). These findings were independent of sex, current BMI, and current substance use.