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Introduction: Cryptosporidiosis is a leading cause of moderate-to-severe diarrhoea globally, and, while it is often self-limited, in immunocompromised individuals, the infection can be associated with significant morbidity and mortality. Diagnosis might be missed or delayed in patients with inflammatory bowel disease (IBD) due to similar presentation, and these patients may also be on immunosuppressive therapies, increasing their risk of infection. Additionally, gastrointestinal infection and dysbiosis may be a risk factor for IBD. Diagnosis, presentation and treatment of cryptosporidiosis in individuals with IBD, as well as any epidemiologic correlations between the two diseases, will be investigated., Methods and Analysis: MEDLINE, Embase, Cochrane Library, CINAHL, Dissertations and Theses Global and grey literature will be searched. Joanna Briggs Institute (JBI) methodology for scoping reviews was used for the protocol and will be for the review. Two reviewers will independently screen studies and extract data. The evidence and presentation of the results will be analysed with input from the review team. Studies of cryptosporidiosis in patients with IBD will be included. Paediatric, adolescent and adult studies in all patient environments will be included. Cases in which Crohn's disease does not affect the intestine and cases in which cryptosporidial infection is not in the intestine will be excluded., Ethics and Dissemination: Published clinical literature will be systematically reviewed, and this work does not directly involve patients. Consequently, ethical review by an institutional review board is not required. Data will be presented at academic conferences, and a culminating report will be published in a peer-reviewed journal. OPEN SCIENCE FRAMEWORK REGISTRATION: https://osf.io/j47mb., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Purpose: Functional neurological disorder (FND) is defined as the presence of neurological symptoms that are inconsistent with a neurological disease. We performed a single-center retrospective study aimed at determining the long-term outcome of FND patients receiving inpatient rehabilitation and the predictors of a good outcome., Methods: A multidisciplinary graded exercise program was provided with one or two daily physiotherapy and occupational therapy sessions on 5 days each week, as well as weekly psychological support. Outcome was assessed using the motor part of the Functional Independence Measure scale (FIM; maximum score of 91) at admission, discharge, and follow-up, with the last assessment performed by phone interview., Results: The 30 included patients were aged 43.6±14.7 years (mean±standard deviation), comprised 70% females, and received a mean of 4 weeks of rehabilitation. The admission FIM score (80.2±8.3) was significantly lower than the discharge FIM score (86.9±4.6; p <0.001, Wilcoxon signed-rank test). No notable difference was observed between discharge and follow-up FIM scores (85.5±8.5, p =0.54). The mean follow-up of the 36-month FIM scores at discharge and follow-up was dichotomized as a good outcome in cases where all items were scored ≥6 (functional independence). Binomial logistic regression showed that absence of a comorbid psychiatric disorder ( p =0.039, odds ratio=10.7) was a predictive factor for a good outcome at follow-up. Other variables (e.g., sex and age) were not significant predictors of clinical outcome (all p ≥0.058)., Conclusions: These results suggest inpatient intensive rehabilitation for motor FND is effective and produces favorable long-term results. Further studies with larger groups are warranted so that the management protocols can be standardized., Competing Interests: The authors have no potential conflicts of interest to disclose., (Copyright © 2024 Korean Neurological Association.)

Introduction: Event-related potential (ERP) studies have identified two time windows associated with recognition memory and interpreted them as reflecting two processes: familiarity and recollection. However, using relatively simple stimuli and achieving high recognition rates, most studies focused on hits and correct rejections. This leaves out some information (misses and false alarms) that according to Signal Detection Theory (SDT) is necessary to understand signal processing., Methods: We used a difficult visual recognition task with colored pictures of different categories to obtain enough of the four possible SDT outcomes and analyzed them with modern ERP methods., Results: Non-parametric analysis of these outcomes identified a single time window (470 to 670 ms) which reflected activity within fronto-central and posterior-left clusters of electrodes, indicating differential processing. The posterior-left cluster significantly distinguished all STD outcomes. The fronto-central cluster only distinguished ERPs according to the subject's response: yes vs. no. Additionally, only electrophysiological activity within the posterior-left cluster correlated with the discrimination index (d')., Discussion: We show that when all SDT outcomes are examined, ERPs of recognition memory reflect a single-time window that may reveal a bottom-up factor discriminating the history of items (i.e. memory strength), as well as a top-down factor indicating participants' decision., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Schneider, Coll, Schnider and Ptak.)

Background and Objectives: Disorientation is a frequent consequence of acute brain injury or diffuse disorders, such as confusional states or dementia. Its anatomical correlates are debated. Impaired memory as its commonly assumed mechanism predicts that disorientation is associated with medial temporal damage. The alternative is that disorientation reflects defective orbitofrontal reality filtering (ORFi) - a specific failure to identify whether thoughts or memories refer to present reality or not. The latter is a function of the posterior orbitofrontal cortex and connected structures. This study examined the mechanisms and anatomical basis of disorientation in an unselected group of patients with first-ever subacute brain injury., Methods: Participants hospitalized for neurorehabilitation were asked to participate in this observational cohort study if they had first-ever organic hemispheric brain dysfunction as evident in a localizable brain lesion or verbal amnesia (often without localizable brain damage). Orientation to time, place, situation and person was tested with a 20-items questionnaire. To identify the mechanisms of disorientation, we determined its correlations with executive tasks, verbal episodic memory, and ORFi in all patients. ORFi was examined with a continuous recognition task, which measures learning and item recognition in the first run, and ORFi as reflected in the increase of false positive responses in the second run (temporal context confusion). Lesions of patients having localizable brain damage were manually delineated and normalized before entering multivariate lesion-symptom-mapping (LSM) to determine anatomical predictors of orientation., Results: Eighty-four patients (61.1 ± 14.4 years, 29 women) were included. Among measures of memory and executive functioning, a step-wise regression retained temporal context confusion (R = -0.71, p < 0.0001), item recognition (R = 0.67, p < 0.0001) and delayed free recall (R = 0.63, p < 0.0001) as significant predictors of orientation. LSM was possible in 67 participants; it revealed an association of disorientation with damage of the right OFC and the bilateral head of the caudate nucleus., Conclusion: Disorientation in non-confused, non-demented patients with first-ever brain damage is associated with impaired orbitofrontal reality filtering and memory dysfunction, but not with executive dysfunction. Its main anatomical determinant is damage to the orbitofrontal cortex and its subcortical relay, the head of the caudate., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Patients with early Alzheimer's disease (AD) have difficulty in learning new information and in detecting novel stimuli. The underlying physiological mechanisms are not well known. We investigated the electrophysiological correlates of the early (< 400 ms), automatic phase of novelty detection and encoding in AD. We used high-density EEG Queryin patients with early AD and healthy age-matched controls who performed a continuous recognition task (CRT) involving new stimuli (New), thought to provoke novelty detection and encoding, which were then repeated up to 4 consecutive times to produce over-familiarity with the stimuli. Stimuli then reappeared after 9-15 intervening items (N-back) to be re-encoded. AD patients had substantial difficulty in detecting novel stimuli and recognizing repeated ones. Main evoked potential differences between repeated and new stimuli emerged at 180-260 ms: neural source estimations in controls revealed more extended MTL activation for N-back stimuli and anterior temporal lobe activations for New stimuli compared to highly familiar repetitions. In contrast, AD patients exhibited no activation differences between the three stimulus types. In direct comparison, healthy subjects had significantly stronger MTL activation in response to New and N-back stimuli than AD patients. These results point to abnormally weak early MTL activity as a correlate of deficient novelty detection and encoding in early AD., (© 2022. The Author(s).)

Though motivational value is a recognized trigger of approach and avoidance behavior, less is known about the potential of reward to capture attention. We here explored whether positive or negative reward modulates the characteristic deficit of patients with left spatial neglect to disengage attention from an ipsilesional distracter. We built our study on recent observations showing that the disengagement deficit is exaggerated for distracters with target-defining features, indicating that task-relevance captures attention. Patients with left neglect and matched healthy controls were asked to react to lateralized, colored targets preceded by a peripheral cue. Crucially, the cue either possessed the color of the target and was thus task-relevant, or was followed by a positive, negative, or neutral symbolic reward. Neglect patients only exhibited a disengagement deficit when cues were task-relevant or were followed by a negative reward. This finding indicates that attentional selection is driven by task-relevance and negative reward, possibly through interactions between limbic and attention networks., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: Return-to-work is often the most important objective of working-age patients with acquired brain injury, but is often difficult to achieve. There is a lack of evidence for effective treatment. This study aimed to assess the benefit of a multidisciplinary neurorehabilitation in a daytime hospital on return-to-work after an acquired brain injury., Design: Retrospective case-control study., Patients: Acquired brain injury patients between 18 and 65 years of age., Methods: Two periods, before (n = 82 patients) and after (n = 89 patients) the implementation of a daytime hospital in our neuro-rehabilitation unit were compared. Patients followed in the daytime hospital received intensive, interdisciplinary, coordinated, individual and group-level physical, cognitive, and vocational rehabilitation. During the control period, patients received outpatient neurorehabilitation with less intensive treatment without interdisciplinary coordination. The main outcome was the proportion of patients returning to > 50% of their premorbid work activity., Results: Fifty-five percent of patients were able to resume more than 50% of their premorbid work level in the daytime hospital period vs 41% in the control period (p = 0.076)., Conclusion: Intensive and coordinated outpatient neurorehabilitation may facilitate return-to-work after an acquired brain injury.

ABSTRACT Prismatic adaptation (PA) with wedge prisms is a non-invasive technique used in the rehabilitation of patients suffering from spatial neglect. Unfortunately, as for many behavioural intervention techniques, it is nearly impossible to achieve adequate blinding using wedge prisms, and the potential benefit of PA in the rehabilitation of neglect remains controversial. In order to study an alternative to wedge prism, we examine whether virtual PA at different degrees of deviation may alleviate signs of neglect in a double-blind design. Fifteen neglect patients participated in three adaptation sessions, which differed by the degree of deviation (0°, 15°, or 30°). Performance in line bisection and item cancellation tasks was measured in virtual reality immediately before and after adaptation. Session allocation was concealed from patients and the examiner. Despite the presence of robust, dose-dependent effects of virtual PA on Open-Loop Pointing (OLP), no transfer to line bisection and item cancellation tests were observed. None of the patients were aware of differences between sessions. Virtual PA did not result in visuo-motor transfer effects despite inducing significant adaptation effects in OLP. Together with recent negative findings of randomized-controlled trials, these findings cast doubt on the general efficacy of PA as a rehabilitation method of spatial neglect.

Objective: To assess the impact of surgical technique in regard to morbidity and mortality after neoadjuvant treatment for esophageal cancer., Background: The SAKK trial 75/08 was a multicenter phase III trial (NCT01107639) comparing induction chemotherapy followed by chemoradiation and surgery in patients with locally advanced esophageal cancer., Methods: Patients in the control arm received induction chemotherapy with cisplatin and docetaxel, followed by concomitant chemoradiation therapy with cisplatin, docetaxel, and 45Gy. In the experimental arm, the same regimen was used with addition of cetuximab. After completion of neoadjuvant treatment, patients underwent esophagectomy. The experimental arm received adjuvant cetuximab. Surgical outcomes and complications were prospectively recorded and analyzed., Results: Total of 259 patients underwent esophagectomy. Overall complication rate was 56% and reoperation rate was 15% with no difference in complication rates for transthoracic versus transhiatal resections (56% vs 54%, P = 0.77), nor for video assisted thoracic surgeries (VATS) versus open transthoracic resections (67% vs 55%, P = 0.32). There was a trend to higher overall complication rates in squamous cell carcinoma versus adenocarcinoma (65% vs 51%, P = 0.035), and a significant difference in ARDS in squamous cell carcinoma with 14% versus 2% in adenocarcinoma (P = 0.0002). For patients with involved lymph nodes, a lymph node ratio of ≥0.1 was an independent predictor of PFS (HR 2.5, P = 0.01) and OS (HR 2.2, P = 0.03)., Conclusions: This trial showed no difference in surgical complication rates between transthoracic and transhiatal resections. For patients with involved lymph nodes, lymph node ratio was an independent predictor of progression free survival and overall survival., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

To sense whether thoughts refer to current reality or not, a capacity called orbitofrontal reality filtering, depends on an orbitofrontal signal when anticipated outcomes fail to occur. Here, we explored the flexibility and precision of outcome processing in a deterministic reversal learning task. Healthy subjects decided which one of two colored squares hid a target stimulus. Brain activity was measured with high-density electroencephalography. Stimuli resembling, but not identical with, the target stimuli were initially processed like different stimuli from 210 to 250 ms, irrespective of behavioral relevance. From 250 ms on, they were processed according to behavioral relevance: If they required a subsequent switch, they were processed like different stimuli; if they had been declared potential targets, they were treated like true targets. Stimuli requiring a behavioral switch induced strong theta activity in orbitofrontal, ventromedial, and medial temporal regions. The study indicates flexible adaptation of anticipations but precise processing of outcomes, mainly determined by behavioral relevance., (© 2022. The Author(s).)

Syndrome of the trephined (SoT) is an underrecognized complication after decompressive craniectomy. We aimed to investigate SoT incidence, clinical spectrum, risk factors, and the impact of the cranioplasty on neurologic recovery. Patients undergoing a large craniectomy (> 80 cm 2 ) and cranioplasty were prospectively evaluated using modified Rankin score (mRS), cognitive (attention/processing speed, executive function, language, visuospatial), motor (Motricity Index, Jamar dynamometer, postural score, gait assessment), and radiologic evaluation within four days before and after a cranioplasty. The primary outcome was SoT, diagnosed when a neurologic improvement was observed after the cranioplasty. The secondary outcome was a good neurologic outcome (mRS 0-3) 4 days and 90 days after the cranioplasty. Logistic regression models were used to evaluate the risk factors for SoT and the impact of cranioplasty timing on neurologic recovery. We enrolled 40 patients with a large craniectomy; 26 (65%) developed SoT and improved after the cranioplasty. Brain trauma, hemorrhagic lesions, and shifting of brain structures were associated with SoT. After cranioplasty, a shift towards a good outcome was observed within 4 days (p = 0.025) and persisted at 90 days (p = 0.005). Increasing delay to cranioplasty was associated with decreased odds of improvement when adjusting for age and baseline disability (odds ratio 0.96; 95% CI, 0.93-0.99, p = 0.012). In conclusion, SoT is frequent after craniectomy and interferes with neurologic recovery. High suspicion of SoT should be exercised in patients who fail to progress or have a previous trauma, hemorrhage, or shifting of brain structures. Performing the cranioplasty earlier was associated with improved and quantifiable neurologic recovery. Graphical abstract., (© 2021. The Author(s).)

Visuo-motor adaptation with optical prisms that displace the visual scene (prism adaptation, PA) has been widely used to study visuo-motor plasticity in healthy individuals and to decrease the lateralized bias of brain-damaged patients suffering from spatial neglect. Several factors may influence PA aftereffects, such as the degree of optical deviation (generally measured in dioptres of wedge prisms) or the direction of the prismatic shift (leftward vs. rightward). However, the mechanisms through which aftereffects of adaptation in healthy individuals and in neglect affect performance in tasks probing spatial cognition remain controversial. For example, some studies have reported positive effects of PA on auditory neglect, while other studies failed to obtain any changes of performance even in the visual modality. We here tested a new adaptation method in virtual reality to evaluate how sensory parameters influence PA aftereffects. Visual vs. auditory-verbal feedback of optical deviations were contrasted to assess whether rightward deviations influence manual and perceptual judgments in healthy individuals. Our results revealed that altered visual, but not altered auditory-verbal feedback induces aftereffects following adaptation to virtual prisms after 30-degrees of deviation. These findings refine current models of the mechanisms underlying the cognitive effects of virtual PA in emphasizing the importance of visual vs. auditory-verbal feedback during the adaptation phase on visuospatial judgments. Our study also specifies parameters which influence virtual PA and its aftereffect, such as the sensory modality used for the feedback., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bourgeois, Schmid, Turri, Schnider and Ptak.)

The medial temporal lobe (MTL) is crucial for memory encoding and recognition. The time course of these processes is unknown. The present study juxtaposed encoding and recognition in a single paradigm. Twenty healthy subjects performed a continuous recognition task as brain activity was monitored with a high-density electroencephalography. The task presented New pictures thought to evoke encoding. The stimuli were then repeated up to 4 consecutive times to produce over-familiarity. These repeated stimuli served as "baseline" for comparison with the other stimuli. Stimuli later reappeared after 9-15 intervening items, presumably associated with new encoding and recognition. Encoding-related differences in evoked response potential amplitudes and in spatiotemporal analysis were observed at 145-300 ms, whereby source estimation indicated MTL and orbitofrontal activity from 145 to 205 ms. Recognition-related activity evoked by late repetitions occurred at 405-470 ms, implicating the MTL and neocortical structures. These findings indicate that encoding of information is initiated before it is recognized. The result helps to explain modifications of memories over time, including false memories, confabulation, and consolidation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Tautvydaitė, Adam-Darqué, Manuel, Ptak and Schnider.)

Anticipations that fail to happen are important drivers of behavioral adaptation. Their processing appears to depend on the context. In a deterministic environment, where a stimulus unequivocally predicts the outcome, processing of absent outcomes involves the posterior orbitofrontal cortex (OFC). Failure has been linked to reality confusion with confabulations and disorientation. In a probabilistic environment, absent outcomes appear to be processed by the anterior cingulate cortex (ACC) rather than the OFC. Failure has been associated with poor decision making and schizophrenia. These data suggest different mechanisms depending on the context. Here, healthy human subjects made two formally similar reversal learning tasks, but one with deterministic, the other with probabilistic instructions. Brain activity was monitored using high-density electroencephalography. We found that in the deterministic task, negative outcomes, which unequivocally call for a behavioral switch, induced a distinct frontal potential at 200-300 msec. Computational modeling indicated a strong association of evoked potentials with prediction error, surprise, and behavioral adaptation. In the probabilistic task, where behavioral adaptation follows the cumulated processing of outcomes, negative outcomes evoked potentials that were associated with prediction error and surprise, but had a weak link with subsequent behavior. Outcome processing in the probabilistic task induced stronger activation than the deterministic task of an extended network including the ACC, OFC and striatum at 300-400 msec. In both tasks, negative outcomes were processed differently from positive outcomes at 400-600 msec, possibly reflecting updating of the outcome record. We conclude that the brain disposes of at least two distinct systems processing outcomes with unequivocal or ambiguous behavioral significance. These systems differ along behavioral, clinical, electrophysiological and anatomical dimensions., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Mesenteric ischemia is associated with poor outcome and high overall mortality. The aim was to analyze an interdisciplinary treatment approach of vascular and visceral specialists focusing on the in-hospital outcome and follow-up in patients with acute and acute-on-chronic mesenteric ischemia., Methods: From 2010 until 2017, 26 consecutive patients with acute or acute on chronic mesenteric ischemia were treated by an interdisciplinary team. Data were prospectively collected and retrospectively evaluated. Throughout the initial examination, the extent of bowel resection was determined by the visceral surgeon and the appropriate mode of revascularization by the vascular surgeon. The routine follow-up included clinical examination and ultrasound- or CT-imaging for patency assessment and overall survival as primary endpoint of the study., Results: Out of 26 patients, 18 (69.2%) were rendered for open repair. Ten patients (38.5%) received reconstruction of the superior mesenteric artery with an iliac-mesenteric bypass. Seven patients (26.9%) underwent thrombembolectomy of the mesenteric artery. One patient received an infra-diaphragmatic aorto-celiac-mesenteric bypass. Out of the 8 patients, who were not suitable for open revascularization, 2 patients (7.7%) were treated endovascularly and 6 (23.1%) underwent explorative laparotomy. The in-hospital mortality was 23% (n = 6). The mean survival of the revascularized group (n = 20) was 51.8 months (95% CI 39.1-64.5) compared to 15.7 months in the non-revascularized group (n = 6) (95% CI - 4.8-36.1; p = 0.08). The median follow-up was 64.6 months. Primary patency in the 16 patients after open and 2 after interventional revascularization was 100% and 89.9% in the follow-up., Conclusion: The interdisciplinary treatment of mesenteric ischemia improves survival if carried out in time. Hereby open revascularization measures are advantageous as they allow bowel assessment, resection, and revascularization in a one-stop fashion especially in advanced cases.

Preterm birth is one of the main causes for neurodevelopmental problems, and has been associated with a wide range of impairments in cognitive functions including executive functions and memory. One of the factors contributing to these adverse outcomes is the intrinsic vulnerability of the premature brain. Neuroimaging studies have highlighted structural and functional alterations in several brain regions in preterm individuals across lifetime. The orbitofrontal cortex (OFC) is crucial for a multitude of complex and adaptive behaviours, and its structure is particularly affected by premature birth. Nevertheless, studies on the functional impact of prematurity on the OFC are still missing. Orbitofrontal Reality filtering (ORFi) refers to the ability to distinguish if a thought is relevant to present reality or not. It can be tested using a continuous recognition task and is mediated by the OFC in adults and typically developing young adolescents. Therefore, the ORFi task was used to investigate whether OFC functioning is affected by prematurity. We compared the neural correlates of ORFi in 35 young adolescents born preterm (below 32 weeks of gestation) and aged 10 to 14 years with 25 full term-born controls. Our findings indicate that OFC activation was required only in the full-term group, whereas preterm young adolescents did not involve OFC in processing the ORFi task, despite being able to correctly perform it., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

The outbreak of Coronavirus Disease 19 (COVID-19) following the Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV-2) viral infection has placed particular pressure on occidental health systems, especially in terms of acute care resources and critical care skills. A number of affected patients subsequently required a rehabilitation process, due to multiple functional limitations, either as a result of an extended stay in intensive care or the consequences of the infection itself. The aim of this article is to report on the Geneva experience in post COVID19 rehabilitation, through 2 clinical vignettes, illustrating the heterogeneity of symptoms and deficits that may be encountered following this disease., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Despite intense research, the neural correlates of stroke-induced deficits of spatial cognition remain controversial. For example, several cortical regions and white-matter tracts have been designated as possible anatomic predictors of spatial neglect. However, many studies focused on local anatomy, an approach that does not harmonize with the notion that brain-behavior relationships are flexible and may involve interactions among distant regions. We studied in humans of either sex resting-state fMRI connectivity associated with performance in line bisection, reading and visual search, tasks commonly used for he clinical diagnosis of neglect. We defined left and right frontal, parietal, and temporal areas as seeds (or regions of interest, ROIs), and measured whole-brain seed-based functional connectivity (FC) and ROI-to-ROI connectivity in subacute right-hemisphere stroke patients. Performance on the line bisection task was associated with decreased FC between the right fusiform gyrus and left superior occipital cortex. Complementary increases and decreases of connectivity between both temporal and occipital lobes predicted reading errors. In addition, visual search deficits were associated with modifications of FC between left and right inferior parietal lobes and right insular cortex. These distinct connectivity patterns were substantiated by analyses of FC between left- and right-hemispheric ROIs, which revealed that decreased interhemispheric and right intrahemispheric FC was associated with higher levels of impairment. Together, these findings indicate that intrahemispheric and interhemispheric cooperation between brain regions lying outside the damaged area contributes to spatial deficits in a way that depends on the different cognitive components recruited during reading, spatial judgments, and visual exploration. SIGNIFICANCE STATEMENT Focal damage to the right cerebral hemisphere may result in a variety of deficits, often affecting the domain of spatial cognition. The neural correlates of these disorders have traditionally been studied with lesion-symptom mapping, but this method fails to capture the network dynamics that underlie cognitive performance. We studied functional connectivity in patients with right-hemisphere stroke and found a pattern of correlations between the left and right temporo-occipital, inferior parietal, and right insular cortex that were distinctively predictive of deficits in reading, spatial judgment, and visual exploration. This finding reveals the importance of interhemispheric interactions and network adaptations for the manifestation of spatial deficits after damage to the right hemisphere., (Copyright © 2020 the authors.)

Bladder function is controlled by the autonomic and somatic nervous system in the spinal cord. It is coordinated in the brainstem. Different areas of the brain are involved in the voluntary control of this reflex functioning. Brain lesions often cause an overactive bladder syndrome with increased voiding frequency and urgency. Urinary incontinence, frequently present, may be linked to overactive bladder and associated motor and cognitive disorders. Urinary retention occurs in the acute phase of a hemispherical lesion and following brainstem lesions. The identification, evaluation and treatment of urinary disorders in brain-damaged patients require a global assessment and integrated management taking the other neurological consequences of brain damage into account., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article

After a brain lesion, emotional and behavioral disorders affect the quality of life of the patients and their relatives. This article aims to give some cues to manage three problems chosen for their high frequency: apathy, aggression and depression. It will be reviewed how to recognize, to evaluate and to treat them., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Introduction: Orbitofrontal reality filtering (ORFi) is a memory mechanism that distinguishes whether a thought is relevant to present reality or not. In adults, it is mediated by the orbitofrontal cortex (OFC). This region is still not fully developed in preteenagers, but ORFi is already active from age 7. Here, we probe the neural correlates of ORFi in early adolescents, hypothesizing that OFC mediates the sense of reality in this population., Methods: Functional magnetic resonance images (fMRI) were acquired in 22 early adolescents during a task composed of two runs: run 1 measuring recognition capacity; run 2 measuring ORFi; each containing two types of images (conditions): distractors (D: images seen for the first time in the current run) and targets (T: images seen for the second time in the current run). Group region of interest (ROI) analysis was performed in a flexible factorial design with two factors (run and condition) using SPM12., Results: We found significant main effects for the experimental run and condition. The bilateral OFC activation was higher during ORFi than during the first run. Additionally, the OFC was more active while processing distractors than targets., Conclusion: These results confirm, for the first time, the role of OFC in reality filtering in early adolescents., (© 2020 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.)

The mediotemporal lobe (MTL), including the hippocampus, is involved in all stages of episodic memory including memory encoding, consolidation, and retrieval. However, the exact timing of the hippocampus' involvement immediately after stimulus encounter remains unclear. In this study, we used high-density 156-channel electroencephalography to study the processing of entirely new stimuli, which had to be encoded, in comparison to highly overlearned stimuli. Sixteen healthy subjects performed a continuous recognition task with meaningful pictures repeated up to four consecutive times. Waveform and topographic cluster analyses of event-related potentials revealed that new items, in comparison to repetitions, were processed significantly differently at 220-300 ms. Source estimation localized activation for processing new stimuli in the right MTL. Our study demonstrates the occurrence of a transient signal from the MTL in response to new information already at 200-300 ms poststimulus onset, which presumably reflects encoding as an initial step toward memory consolidation., (© 2019 Wiley Periodicals, Inc.)

Immediately repeated meaningful pictures in a continuous recognition task induce a positive frontal potential at about 200-300 ms, which appears to emanate from the medial temporal lobe (MTL) centered on the hippocampus, as concluded from inverse solutions, coherence measurements, and depth electrode recordings in humans. In this study, we tested patients with unilateral MTL lesions due to stroke to verify the provenance of this signal and its association with the spacing effect (SE)-the improved learning of material encountered in spaced rather than massed presentation. We found that unilateral left or right MTL lesions abolished the early frontal MTL-mediated signal but not the spacing effect. We conclude that the SE does not depend on MTL integrity. We suggest that the early frontal signal at 200-300 ms after immediate picture repetition may serve as a direct biomarker of MTL integrity that may be useful in the early stages of diseases like Alzheimer's., (© 2018 Wiley Periodicals, Inc.)

Background: A false sense of reality is a characteristic of schizophrenia spectrum disorders (SSD). Reality confusion may also emanate from posterior orbitofrontal cortex (OFC) lesions, as evident in confabulations that patients act upon and disorientation. This confusion can be measured by repeated runs of a continuous recognition task (CRT): patients increase their false positive rate from the second run on, failing to realize that an item is not a repetition within the current run. Correct handling of these stimuli, a faculty called orbitofrontal reality filtering (ORFi), induces a distinct frontal potential at 200-300 ms, the "ORFi potential". Patients with schizophrenia have been reported to fail in this task, too. Here, we explored the electrophysiology of ORFi in SSD., Methods: Evoked potentials, source, and connectivity analyses derived from high-density electroencephalograms of 17 patients with SSD and 15 age-matched healthy controls performing two runs of a CRT., Results: Although the patients obtained normal performance, they did not normally express the frontal potential typical of ORFi between 200 and 300 ms. Coherence analysis demonstrated virtually absent functional connectivity in the theta band within the memory network in this period. Source analysis showed increased activity in left medial temporal and prefrontal regions in patients., Conclusions: SSD patients appear to invoke compensatory resources to handle the challenges of reality filtering. An abnormal ORFi potential may be an early biomarker of SSD., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: The long-term follow up data of 2 prospective phase II trials is reported (NCT00072033, NCT00445861), which investigated neoadjuvant chemoradiation followed by surgery in patients with esophageal carcinoma. Postoperative complications as well as prognostic factors and patterns of relapse during long-term observation are shown., Summary of Background Data: Long-term follow-up is often missing in the complex setting of multimodal treatments of esophageal carcinoma; this leads to rather undifferentiated follow-up guidelines for this tumor entity., Methods: In the first trial, patients received induction chemotherapy followed by chemoradiation and surgery. In the second trial, cetuximab was added to the same neoadjuvant treatment concomitant with induction chemotherapy and chemoradiation., Results: Eighty-two patients underwent surgery; the median follow-up time was 6.8 and 6.4 years, respectively. Fifty-five percent were diagnosed with adenocarcinoma, 80% clinically node-positive, 68% received transthoracic esophagectomy, and 32% transhiatal or transmediastinal resection. Five patients died postoperatively in-hospital due to complications (6%). The median overall survival was 4.3 years, and the median event-free survival was 2.7 years. Patients with adenocarcinoma rarely relapsed after a 3-year event-free survival. Whereas patients with residual tumor cells after neoadjuvant therapy primarily experienced relapse within the first 2 postoperative years, this in contrast to several patients with complete remission who also experienced late relapses 4 years after surgery., Conclusion: After curative surgery in a multimodal setting, the histological type and the response to neoadjuvant therapy predicted the time frame of relapse; this knowledge may influence further follow-up guidelines for esophageal carcinoma.

In Switzerland, alcohol consumption is often trivialized and widely accepted as normal behavior. However, even in small quantities, repeated alcohol intake can cause injury to both the central nervous system and the peripheral one. Various mechanisms are involved : direct neurotoxicity, metabolic disorders, vitamin deficiencies, systemic injuries (hepatic, cardiovascular, immune), and accidents. This article describes potential neurological complications and their mechanisms, emphasizing the importance of early screenings for abusive consumption., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêt en relation avec cet article.

Background: A successful interplay between prefrontal and domain-specific language areas is critical for language processing. Previous studies involving people with aphasia have shown that executive control processes might act on lexical-semantic representations during retrieval. Modulating the prefrontal control network by means of noninvasive brain stimulation might, therefore, improve lexical access in people with aphasia., Objective: The present study investigates the effects of prefrontal transcranial direct current stimulation (tDCS) on lexical access in chronic poststroke aphasia., Methods: We report data of 14 participants with chronic poststroke aphasia. We used a sham-tDCS (S-tDCS) controlled and double-blind within-subjects design. Performances in picture naming, verbal fluency, and word repetition were assessed immediately after stimulation., Results: As compared with S-tDCS, anodal tDCS (A-tDCS) improved verbal fluency as well as the speed of naming high frequency words, but not word repetition., Conclusion: The results of our study suggest that the brain network dedicated to lexical retrieval processing can be facilitated by A-tDCS over the left dorsolateral prefrontal cortex. This finding supports the notion that strengthening executive control functions after stroke could complement speech and language-focused therapy.

Background and Purpose: Basal ganglia play a pivotal role in procedural memory. However, the correlation between skill learning and striatal ¹²³I-ioflupane uptake in Parkinson's disease (PD) has not been reported previously. Our objective was to determine whether visuomotor skill learning is associated with striatal ¹²³I-ioflupane uptake in early PD., Methods: We designed a case-control study to assess learning and consolidation of a visuomotor learning task (mirrored drawing of star-shaped figures) performed on two consecutive days by early-PD patients (disease duration <2 years) and age-matched healthy subjects. Outcomes were the error rate and time per trial, as well as performance indices to assess the relative improvement on the first day (learning) and the retention on the second day (consolidation). For PD patients, we evaluated the correlation of skill learning with semiquantitative ¹²³I-ioflupane uptake., Results: We included 9 PD patients and 10 control subjects with the same baseline characteristics (age, male/female ratio, educational level, Mini Mental State Examination score, and Hospital Anxiety and Depression Scale score, all p >0.18) other than the score on part III of the Movement Disorders Society Unified Parkinson's Disease Rating Scale, which was higher in the PD patients (mean±SD: 15.0±10.4 vs. 1.3±1.1, p <0.001). The learning indices were the same in the two groups ( p >0.5), whereas PD patients showed a lower consolidation index for the time per trial ( p =0.009). Moreover, this performance was correlated with uptake in the right caudate nucleus (Spearman's rho=0.82, p =0.007) and the right striatum (Spearman's rho=0.67, p =0.049), including when multiple linear regression adjusting for the levodopa equivalent daily dose was performed ( p =0.005 for the caudate nucleus and p =0.024 for the striatum)., Conclusions: This study provides evidence of a correlation between procedural memory impairment and striatal dopaminergic dysfunction in early PD., Competing Interests: The authors have no financial conflicts of interest., (Copyright © 2018 Korean Neurological Association.)

Social learning in animals is now well documented, but few studies have determined the contexts shaping when social learning is deployed. Theoretical studies predict copying of conspecifics gaining higher payoffs [1-4], a bias demonstrated in primates only in captivity [5]. In the wild, research has shown selective attention toward the philopatric sex, a group's stable core [6]. Here, we report the first rigorous experimental test of the existence of a payoff bias in wild primates and its interaction with the sex of the model. We created a payoff bias in which an immigrant alpha male in each of three groups of wild vervet monkeys received five times more food upon opening a foraging box than did the philopatric alpha female, whereas in two control groups, male and female models received the same amount of food. We tested whether this payoff asymmetry would override the previously documented selective learning from resident females. Group members were tested after having watched both models. When both models received the same amount of food, audience members copied the female model significantly more than the male model, confirming previous findings. However, when a marked payoff bias was introduced, male, but not female, vervet monkeys significantly more often copied the male model receiving a higher payoff. These results demonstrate behavioral flexibility in the dispersing sex in these primates and suggest that the philopatric sex can afford to be more conservative in their social learning. Our findings show that multiple social-learning biases can coexist and interact within the same species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Procedural memory refers to skills acquired through practice and depends on cortico-striatal and cortico-cerebellar circuits. These circuits are typically affected in Parkinson's disease (PD), leading to impaired skill learning, including defective offline consolidation, early in the course of the disease. Evidence points to a role of slow oscillations (<4 Hz) during sleep for offline consolidation. However recent studies showed consolidation over the course of the day, suggesting that consolidation may arise during wakefulness, too. Here we investigate whether functional connectivity (FC) at rest after visuo-motor skill learning is associated with the extent of offline improvements in healthy controls and PD patients. Nineteen participants (9 PD, 10 healthy controls) performed a mirror-drawing task. High-density 156-channel resting state EEG was recorded before and immediately after training. Performance on the task was measured again 24 h later to test for offline consolidation. Delta-band (1-3.5 Hz) FC centered on the left parietal cortex after training predicted offline consolidation. Weak FC was observed in most healthy controls and associated with marked overnight improvement, while strong FC was observed in most PD patients and associated with weak offline consolidation or loss of the skill. These findings indicate that offline consolidation starts immediately after visuo-motor skill learning in brain regions and frequencies typically involved in sleep-related consolidation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Spontaneous brain activity at rest is highly organized even when the brain is not explicitly engaged in a task. Functional connectivity (FC) in the alpha frequency band (α, 8-12 Hz) during rest is associated with improved performance on various cognitive and motor tasks. In this study we explored how FC is associated with visuo-motor skill learning and offline consolidation. We tested two hypotheses by which resting-state FC might achieve its impact on behavior: preparing the brain for an upcoming task or consolidating training gains. Twenty-four healthy participants were assigned to one of two groups: The experimental group (n = 12) performed a computerized mirror-drawing task. The control group (n = 12) performed a similar task but with concordant cursor direction. High-density 156-channel resting-state EEG was recorded before and after learning. Subjects were tested for offline consolidation 24h later. The Experimental group improved during training and showed offline consolidation. Increased α-FC between the left superior parietal cortex and the rest of the brain before training and decreased α-FC in the same region after training predicted learning. Resting-state FC following training did not predict offline consolidation and none of these effects were present in controls. These findings indicate that resting-state alpha-band FC is primarily implicated in providing optimal neural resources for upcoming tasks., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objectives: To develop and test a new immersive digital technology for complex regional pain syndrome (CRPS) that combines principles from mirror therapy and immersive virtual reality and the latest research from multisensory body processing., Methods: In this crossover double-blind study, 24 patients with CRPS and 24 age- and sex-matched healthy controls were immersed in a virtual environment and shown a virtual depiction of their affected limb that was flashing in synchrony (or in asynchrony in the control condition) with their own online detected heartbeat (heartbeat-enhanced virtual reality [HEVR]). The primary outcome measures for pain reduction were subjective pain ratings, force strength, and heart rate variability (HRV)., Results: HEVR reduced pain ratings, improved motor limb function, and modulated a physiologic pain marker (HRV). These significant improvements were reliable and highly selective, absent in control HEVR conditions, not observed in healthy controls, and obtained without the application of tactile stimulation (or movement) of the painful limb, using a readily available biological signal (the heartbeat) that is most often not consciously perceived (thus preventing placebo effects)., Conclusions: Next to these specific and well-controlled analgesic effects, immersive HEVR allows the application of prolonged and repeated doses of digital therapy, enables the automatized integration with existing pain treatments, and avoids application of painful bodily cues while minimizing the active involvement of the patient and therapist., Classification of Evidence: This study provides Class III evidence that HEVR reduces pain and increases force strength in patients with CRPS., (© 2018 American Academy of Neurology.)

Synchronization of neural activity as measured with functional connectivity (FC) is increasingly used to study the neural basis of brain disease and to develop new treatment targets. However, solid evidence for a causal role of FC in disease and therapy is lacking. Here, we manipulated FC of the ipsilesional primary motor cortex in ten chronic human stroke patients through brain-computer interface technology with visual neurofeedback. We conducted a double-blind controlled crossover study to test whether manipulation of FC through neurofeedback had a behavioral effect on motor performance. Patients succeeded in increasing FC in the motor cortex. This led to improvement in motor function that was significantly greater than during neurofeedback training of a control brain area and proportional to the degree of FC enhancement. This result provides evidence that FC has a causal role in neurological function and that it can be effectively targeted with therapy.

Brain-computer interfaces (BCI) are used in stroke rehabilitation to translate brain signals into intended movements of the paralyzed limb. However, the efficacy and mechanisms of BCI-based therapies remain unclear. Here we show that BCI coupled to functional electrical stimulation (FES) elicits significant, clinically relevant, and lasting motor recovery in chronic stroke survivors more effectively than sham FES. Such recovery is associated to quantitative signatures of functional neuroplasticity. BCI patients exhibit a significant functional recovery after the intervention, which remains 6-12 months after the end of therapy. Electroencephalography analysis pinpoints significant differences in favor of the BCI group, mainly consisting in an increase in functional connectivity between motor areas in the affected hemisphere. This increase is significantly correlated with functional improvement. Results illustrate how a BCI-FES therapy can drive significant functional recovery and purposeful plasticity thanks to contingent activation of body natural efferent and afferent pathways.

Background: This open-label, phase III trial compared chemoradiation followed by surgery with or without neoadjuvant and adjuvant cetuximab in patients with resectable esophageal carcinoma., Patients and Methods: Patients were randomly assigned (1 : 1) to two cycles of chemotherapy (docetaxel 75 mg/m2, cisplatin 75 mg/m2) followed by chemoradiation (45 Gy, docetaxel 20 mg/m2 and cisplatin 25 mg/m2, weekly for 5 weeks) and surgery, with or without neoadjuvant cetuximab 250 mg/m2 weekly and adjuvant cetuximab 500 mg/m2 fortnightly for 3 months. The primary end point was progression-free survival (PFS)., Results: In total, 300 patients (median age, 61 years; 88% male; 63% adenocarcinoma; 85% cT3/4a, 90% cN+) were assigned to cetuximab (n = 149) or control (n = 151). The R0-resection rate was 95% for cetuximab versus 97% for control. Postoperative treatment-related mortality was 6% in both arms. Median PFS was 2.9 years [95% confidence interval (CI), 2.0 to not reached] with cetuximab and 2.0 years (95% CI, 1.5-2.8) with control [hazard ratio (HR), 0.79; 95% CI, 0.58-1.07; P = 0.13]. Median overall survival (OS) time was 5.1 years (95% CI, 3.7 to not reached) versus 3.0 years (95% CI, 2.2-4.2) for cetuximab and control, respectively (HR, 0.73; 95% CI, 0.52-1.01; P = 0.055). Time to loco-regional failure after R0-resection was significantly longer for cetuximab (HR 0.53; 95% CI, 0.31-0.90; P = 0.017); time to distant failure did not differ between arms (HR, 1.01; 95% CI, 0.64-1.59, P = 0.97). Cetuximab did not increase adverse events in neoadjuvant or postoperative settings., Conclusion: Adding cetuximab to multimodal therapy significantly improved loco-regional control, and led to clinically relevant, but not-significant improvements in PFS and OS in resectable esophageal carcinoma., Clinical Trial Information: NCT01107639.

Objective: To investigate the effects of cathodal transcranial direct current stimulation (tDCS) and continuous theta burst stimulation (cTBS) on neural network connectivity and motor recovery in individuals with subacute stroke., Design: Double-blinded, randomized, placebo-controlled study., Setting: University hospital rehabilitation unit., Participants: Inpatients with stroke (N=41; mean age, 65y; range, 28-85y; mean weeks poststroke, 5; range, 2-10) with resultant paresis in the upper extremity (mean Fugl-Meyer score, 14; range, 3-48)., Interventions: Subjects with stroke were randomly assigned to neuronavigated cTBS (n=14), cathodal tDCS (n=14), or sham transcranial magnetic stimulation/sham tDCS (n=13) over the contralesional primary motor cortex (M1). Each subject completed 9 stimulation sessions over 3 weeks, combined with physical therapy., Main Outcome Measures: Brain function was assessed with directed and nondirected functional connectivity based on high-density electroencephalography before and after stimulation sessions. Primary clinical end point was the change in slope of the multifaceted motor score composed of the upper extremity Fugl-Meyer Assessment score, Box and Block test score, 9-Hole Peg Test score, and Jamar dynamometer results between the baseline period and the treatment time., Results: Neither stimulation treatment enhanced clinical motor gains. Cathodal tDCS and cTBS induced different neural effects. Only cTBS was able to reduce transcallosal influences from the contralesional to the ipsilesional M1 during rest. Conversely, tDCS enhanced perilesional beta-band oscillation coherence compared with cTBS and sham groups. Correlation analyses indicated that the modulation of interhemispheric driving and perilesional beta-band connectivity were not independent mediators for functional recovery across all patients. However, exploratory subgroup analyses suggest that the enhancement of perilesional beta-band connectivity through tDCS might have more robust clinical gains if started within the first 4 weeks after stroke., Conclusions: The inhibition of the contralesional M1 or the reduction of interhemispheric interactions was not clinically useful in the heterogeneous group of subjects with subacute stroke. An early modulation of perilesional oscillation coherence seems to be a more promising strategy for brain stimulation interventions., (Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Gait asymmetry and dynamic balance impairments observed in post-stroke individuals increase their risk of fall. Moreover, walking while performing a cognitive task (i.e. dual-task) disturbs the control of balance in post-stroke individuals. Here we investigated the mediolateral dynamic stability in twenty-two community-dwelling participants (12 post-strokes and 10 healthy controls) while walking in single-task (normal gait) and four different dual-tasks (cognitive-motor interference). Positions of the extrapolated center of mass and mediolateral widths of both margin of stability and base of support were extracted from 35 marker trajectories. Post-stroke participants presented larger margin of stability and base of support than controls during single-task (both p < 0.01), with a larger margin of stability on the non-paretic side than on the paretic side at ipsilateral foot-strike (p < 0.05). No significant effect of the dual-task was found between groups. In post-stroke participants, dual-task induced slight modification of the mediolateral stability strategy, as the margin of stability was not different between the two limbs at foot-strike, and significantly reduced the performance in every cognitive task. Post-stroke participants increased their dynamic stability in the frontal plane in single-task by extending their base of support and mainly relying on their non-paretic limb. Under cognitive-motor interference (dual-task), post-stroke participants prioritized dynamic stability over cognitive performance to ensure a safe locomotion. Thus, rehabilitation programs should consider both dynamic balance and dual-task training, even at a chronic delay following stroke, to reduce the risk of fall in post-stroke individuals., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Evolution of motor function during the first months after stroke is stereotypically bifurcated, consisting of either recovery to about 70% of maximum possible improvement ("proportional recovery, PROP") or in little to no improvement ("poor recovery, POOR"). There is currently no evidence that any rehabilitation treatment will prevent POOR and favor PROP., Objective: To perform a longitudinal and multimodal assessment of functional and structural changes in brain organization associated with PROP., Methods: Fugl-Meyer Assessments of the upper extremity and high-density electroencephalography (EEG) were obtained from 63 patients, diffusion tensor imaging from 46 patients, at 2 and 4 weeks (T0) and at 3 months (T1) after stroke onset., Results: We confirmed the presence of 2 distinct recovery patterns (PROP and POOR) in our sample. At T0, PROP patients had greater integrity of the corticospinal tract (CST) and greater EEG functional connectivity (FC) between the affected hemisphere and rest of the brain, in particular between the ventral premotor and the primary motor cortex. POOR patients suffered from degradation of corticocortical and corticofugal fiber tracts in the affected hemisphere between T0 and T1, which was not observed in PROP patients. Better initial CST integrity correlated with greater initial global FC, which was in turn associated with less white matter degradation between T0 and T1., Conclusions: These findings suggest links between initial CST integrity, systems-level cortical network plasticity, reduction of white matter atrophy, and clinical motor recovery after stroke. This identifies candidate treatment targets.

Group living promotes opportunities for both cooperation and competition. Selection on the ability to cope with such opposing social opportunities has been proposed as a driving force in the evolution of large brains in primates and other social species. However, we still know little about the degree of complexity involved in such social strategies. Here, we report advanced social strategies in wild vervet monkeys. Building on recent experimental evidence that subordinate females trade grooming for tolerance from higher-ranking individuals during foraging activities, we show that the audience composition strongly affects this trade. First, tolerance was lower if the audience contained individuals that outranked the subordinate partner, independently of audience size and kinship relationships. Second, we found a significant interaction between previous grooming and relative rank of bystanders: dominant subjects valued recent grooming by subordinates while intermediate ranked subjects valued the option to aggress subordinate partners in the presence of a dominant audience. Aggressors were also more likely to emit coalition recruitment calls if the audience contained individuals that outranked the subordinate partner. In conclusion, vervet monkeys include both recent grooming and knowledge about third-party relationships to make complex decisions when trading grooming for tolerance, leading to a finely balanced trade-off between reciprocation and opportunities to reinforce rank relationships., (© 2017 The Author(s).)

Visual attention can be deployed in space-based or object-centered reference frames. Right-hemisphere damage may lead to distinct deficits of space- or object-based processing, and such dissociations are thought to underlie the heterogeneous nature of spatial neglect. Previous studies have suggested that object-centered processing deficits (such as in copying, reading or line bisection) result from damage to retro-rolandic regions while impaired spatial exploration reflects damage to more anterior regions. However, this evidence is based on small samples and heterogeneous tasks. Here, we tested a theoretical model of neglect that takes in account the space- and object-based processing and relates them to neuroanatomical predictors. One hundred and one right-hemisphere-damaged patients were examined with classic neuropsychological tests and structural brain imaging. Relations between neglect measures and damage to the temporal-parietal junction, intraparietal cortex, insula and middle frontal gyrus were examined with two structural equation models by assuming that object-centered processing (involved in line bisection and single-word reading) and space-based processing (involved in cancelation tasks) either represented a unique latent variable or two distinct variables. Of these two models the latter had better explanatory power. Damage to the intraparietal sulcus was a significant predictor of object-centered, but not space-based processing, while damage to the temporal-parietal junction predicted space-based, but not object-centered processing. Space-based processing and object-centered processing were strongly intercorrelated, indicating that they rely on similar, albeit partly dissociated processes. These findings indicate that object-centered and space-based deficits in neglect are partly independent and result from superior parietal and inferior parietal damage, respectively.

Any thought, whether it refers to the present moment or reflects an imagination, is again encoded as a new memory trace. Orbitofrontal reality filtering (ORFi) denotes an on-line mechanism which verifies whether upcoming thoughts relate to ongoing reality or not. Its failure induces reality confusion with confabulations and disorientation. If the result of this process were simultaneously encoded, it would easily explain later distinction between memories relating to a past reality and memories relating to imagination, a faculty called reality monitoring. How the brain makes this distinction is unknown but much research suggests that it depends on processes active when information is encoded. Here we explored the precise timing between ORFi and encoding as well as interactions between the involved brain structures. We used high-density evoked potentials and two runs of a continuous recognition task (CRT) combining the challenges of ORFi and encoding. ORFi was measured by the ability to realize that stimuli appearing in the second run had not appeared in this run yet. Encoding was measured with immediately repeated stimuli, which has been previously shown to induce a signal emanating from the medial temporal lobe (MTL), which has a protective effect on the memory trace. We found that encoding, as measured with this task, sets in at about 210 ms after stimulus presentation, 35 ms before ORFi. Both processes end at about 330 ms. Both were characterized by increased coherence in the theta band in the MTL during encoding and in the orbitofrontal cortex (OFC) during ORFi. The study suggests a complex interaction between OFC and MTL allowing for thoughts to be re-encoded while they undergo ORFi. The combined influence of these two processes at 200-300 ms may leave a memory trace that allows for later effortless reality monitoring in most everyday situations.

The dorsal frontoparietal network (dFPN) of the human brain assumes a puzzling variety of functions, including motor planning and imagery, mental rotation, spatial attention, and working memory. How can a single network engage in such a diversity of roles? We propose that cognitive computations relying on the dFPN can be pinned down to a core function underlying offline motor planning: action emulation. Emulation creates a dynamic representation of abstract movement kinematics, sustains the internal manipulation of this representation, and ensures its maintenance over short time periods. Based on these fundamental characteristics, the dFPN has evolved from a pure motor control network into a domain-general system supporting various cognitive and motor functions., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background and Purpose: Motor recovery after stroke can be characterized into two different patterns. A majority of patients recover about 70% of initial impairment, whereas some patients with severe initial deficits show little or no improvement. Here, we investigated whether recovery from visuospatial neglect and aphasia is also separated into two different groups and whether similar proportions of recovery can be expected for the two cognitive functions., Methods: We assessed 35 patients with neglect and 14 patients with aphasia at 3 weeks and 3 months after stroke using standardized tests. Recovery patterns were classified with hierarchical clustering and the proportion of recovery was estimated from initial impairment using a linear regression analysis., Results: Patients were reliably clustered into two different groups. For patients in the first cluster (n = 40), recovery followed a linear model where improvement was proportional to initial impairment and achieved 71% of maximal possible recovery for both cognitive deficits. Patients in the second cluster (n = 9) exhibited poor recovery (<25% of initial impairment)., Conclusions: Our findings indicate that improvement from neglect or aphasia after stroke shows the same dichotomy and proportionality as observed in motor recovery. This is suggestive of common underlying principles of plasticity, which apply to motor and cognitive functions., (© 2017 EAN.)