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• Atrial fibrillation burden was low after ablation therapy. • Atrial fibrillation burden had divergent effects on executive functions and learning. • Atrial fibrillation burden had no impact on overall cognitive performance. Atrial fibrillation (AF) is associated with cognitive decline and dementia irrespective of AF-related ischemic stroke. We investigated whether AF burden after ablation in patients with symptomatic paroxysmal AF has an impact on cognitive function. After enrolment to the prospective MACPAF study, study patients received an insertable loop recorder (ILR) and underwent serial neurological/cognitive assessment. To compare cognitive function, the delta of baseline and six months test results (Δ pre/post) and a score to assess overall cognitive performance were computed. Thirty patients (median age 65 years (IQR 57–69), 40% female) were divided into groups according to median AF burden (<0.5% vs. ≥0.5%) after ablation. Overall cognitive performance did not differ in patients with an AF burden < 0.5% (median 120% [IQR 100–150]) vs. ≥0.5% (median 120% [IQR 100–160]) within six months after ablation (p = 0.74). Comparing Δ pre/post , patients with an AF burden ≥ 0.5% showed significantly better results in the digit-span backwards test (median + 1 [IQR 0 - +2 points]) compared to patients with an AF burden < 0.5% (median 0 [IQR −1–+1]) six months after ablation (p = 0.03). In patients with an AF burden < 0.5%, there was a statistical trend towards better results in the RAVLT test (median + 3 [IQR 0–+4]; p = 0.08) and the ROC test (median + 3 [IQR −1–+5; p = 0.07) compared to patients with an AF burden ≥ 0.5% (median −1 [IQR −3–+2] words and median −1 [IQR −5–+2] points, respectively). Therefore, AF burden had no significant impact on cognitive performance within six months after ablation. Clinical Trial Registration: clinicaltrials.gov NCT01061931. [ABSTRACT FROM AUTHOR]

Background The majority of patients with anti- N -methyl-D-aspartate receptor (NMDAR) encephalitis suffer from persistent memory impairment despite unremarkable routine clinical magnetic resonance imaging. With improved acute care in these patients, neurocognitive impairment represents the major contributor to long-term morbidity and has thus become a focus of attention. Methods Forty patients with anti-NMDAR encephalitis after the acute disease stage and 25 healthy control subjects underwent multimodal structural imaging that combined volumetry of hippocampal subfields with analysis of hippocampal microstructural integrity. Verbal and visuospatial memory performance was assessed in all patients and correlation and mediation analyses were performed to examine associations between hippocampal structural integrity, memory performance, and disease severity. Results Hippocampal volumes were significantly reduced in patients and hippocampal subfield analysis revealed bilateral atrophy of the input and output regions of the hippocampal circuit. Microstructural integrity was impaired in both hippocampi in patients. Importantly, hippocampal volumetric and microstructural integrity measures correlated with memory performance and disease severity and duration. Mediation analysis revealed that hippocampal microstructure mediated the effect of disease severity on memory performance. Conclusions Data from this largest cohort of anti-NMDAR encephalitis patients that underwent extensive multimodal magnetic resonance imaging demonstrate that structural hippocampal damage and associated memory deficits are important long-term sequelae of the encephalitis. Correlation with disease duration and severity highlights the need for rapid diagnosis and adequate immunotherapy to prevent persistent damage to the hippocampus. Advanced imaging protocols may allow a more detailed analysis of structural damage to assess disease progression in clinical routine examinations and for therapy evaluation in prospective trials. [ABSTRACT FROM AUTHOR]

Abstract: The current study investigated the involvement of all four components of Baddeley''s [Baddeley, A. D. (2000). The episodic buffer: A new component of working memory? Trends in Cognitive Sciences, 4, 417–423] revised working memory model in deficits of planning accompanying Parkinson''s disease (PD). PD resulted in poorer formulation and execution of plans, as measured by the Tower of London task. PD also reduced the efficiency of the episodic buffer and central executive components of working memory, but did not influence storage of verbal or visuospatial information. Planning deficits in PD were particularly linked to problems in integrating multimodal short-term information with long-term memory (episodic buffer). These results emphasize the importance of integrative and executive processing in cognitive problems in PD, rather than simple memory deficits. [Copyright &y& Elsevier]

Abstract: The medial temporal lobe (MTL) has long been considered essential for declarative long-term memory, whereas the fronto-parietal cortex is generally seen as the anatomical substrate of short-term memory. This traditional dichotomy is questioned by recent studies suggesting a possible role of the MTL for short-term memory. In addition, there is no consensus on a possible specialization of MTL sub-regions for memory of associative information. Here, we investigated short-term memory for single features and feature associations in three humans with post-surgical lesions affecting the right hippocampal formation and in 10 healthy controls. We used three delayed-match-to-sample tasks with two delays (900/5000ms) and three set sizes (2/4/6 items). Subjects were instructed to remember either colours, locations or colour–location associations. In colour-only and location-only conditions, performance of patients did not differ from controls. By contrast, a significant group difference was found in the association condition at 5000ms delay. This difference was largely independent of set size, thus suggesting that it cannot be explained by the increased complexity of the association condition. These findings show that the hippocampal formation plays a significant role for short-term memory of simple visuo-spatial associations, and suggest a specialization of MTL sub-regions for associative memory. [Copyright &y& Elsevier]