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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. Brain-computer interface (BCI) can improve motor skills on stroke patients. This study shows that BCI-controlled neuromuscular electrical stimulation therapy can cause cortical reorganization due to activation of efferent and afferent pathways, and this effect can be long lasting in a brain region specific manner.

Confabulation, the emergence of memories of events and experiences which in reality never took place, has puzzled clinicians for over a century. There are different forms, which partly of fully dissociate from each other, both functionally and anatomically: 1) simple provoked confabulations, that is, intrusions in memory tests, which appear to be a normal response to a faulty memory; 2) momentary confabulations that patients produce in discussions or upon questioning; they probably have different mechanisms in different diseases; 3) fantastic confabulations that are illogical and nonsensical; they have been observed in confusional states, in severe dementia, and in severe, untreated psychosis; 4) behaviourally spontaneous confabulations which reflect a confusion of reality in thinking, are often concordant with the patient's spontaneous behaviour, and which are associated with disorientation and amnesia. This talk focuses on this latter form, which constitutes a natural model for how the brain creates reality in thinking. In behaviourally spontaneous confabulation, actions are intermittently guided by memories that may have justly guided their behaviour in the past but which do not pertain to true ongoing reality. This failure appears to result from an inability to suppress the interference of memories that do not pertain to now. Lesions involve the posterior medial orbitofrontal cortex (area 13) or structures directly connected with it. Functional imaging and electrophysiological studies suggested that this “suppression” is conveyed by area 13 and indeed corresponds to a filtering of upcoming memories according to their relation with ongoing reality. This filtering appears to adjust the “cortical format” of memories at an early stage of processing, at 200–300 ms, before processes of (conscious) recognition and re-encoding set in. The mechanism by which the orbitofrontal cortex exerts this filtering has been unknown. A recent study showed that disorientation and behaviourally spontaneous confabulations are tightly associated with deficient extinction capacity—the ability to integrate negative prediction errors into behaviour. Thus, rather than invoking high-level monitoring functions, the human brain seems to make use of an ancient biological faculty, extinction, to keep thought and behaviour in phase with reality.

We tested the use of multiplex real-time PCR for detection and quantification of Campylobacter jejuni and Campylobacter coli on broiler carcass neck skin samples collected during 2008 from slaughterhouses in Switzerland. Results from an established TaqMan assay based on two different targets (hipO and ceuE for C. jejuni and C. coli, respectively) were corroborated with data from a newly developed assay based on a single-nucleotide polymorphism in the fusA gene, which allows differentiation between C. jejuni and C. coli. Both multiplex real-time PCRs were applied simultaneously for direct detection, differentiation, and quantification of Campylobacter from 351 neck skin samples and compared with culture methods. There was good correlation in detection and enumeration between real-time PCR results and quantitative culture, with real-time PCR being more sensitive. Overall, 251 (71.5%) of the samples were PCR positive for Campylobacter, with 211 (60.1%) in the hipO-ceuE assays, 244 (69.5%) in the fusA assay, and 204 (58.1%) of them being positive in both PCR assays. Thus, the fusA assay was similarly sensitive to the enrichment culture (72.4% positive); however, it is faster and allows for quantification. In addition, real-time PCR allowed for species differentiation; roughly 60% of positive samples contained C. jejuni, less than 10% C. coli, and more than 30% contained both species. Real-time PCR proved to be a suitable method for direct detection, quantification, and differentiation of Campylobacter from carcasses, and could permit time-efficient surveillance of these zoonotic agents.

Key Points Broadly defined, confabulation is the production of fictitious stories. There are different forms of confabulation, which have been classified in different ways by several authors. This multiplicity has made it difficult to understand the neural basis of the different forms. This article deals with one specific type — spontaneous confabulation. Spontaneous confabulation is a profound derangement of thought in which the patients' ongoing reality and planning are dominated by their past experiences and habits. So, confabulations are the patients' honest view of their perceived reality, and therefore lead them to act in accordance with mistaken beliefs. The mechanisms that underlie the production of these fictitious stories are not yet fully understood, largely because many studies have not distinguished between patients with different forms of confabulation. As a result, there are many descriptive ideas, but few with predictive value. Despite this, the consensus is that confabulation is best characterized as a memory disorder. In the view presented here, confabulation stems from confusion between presently relevant and irrelevant memories. More specifically, confusion seems to result from failure to suppress activated but presently irrelevant memory traces — the monitoring of ongoing reality. Spontaneous confabulation is only observed in people with brain lesions. Although the extent of such lesions is variable, they tend always to involve the posterior orbitofrontal cortex, or the anterior limbic structures that are directly connected with it. Imaging studies have confirmed this conclusion, as these regions are activated by tasks on which confabulating patients fail. The adaptation of thought and behaviour to ongoing reality that seems to be affected in confabulators is mediated by the anterior limbic system, and acts by suppressing activated memory traces that do not pertain to ongoing reality. This finding allows exploration of how suppression works in the healthy brain. Electroencephalographic studies indicate that, at the cortical level, suppression is an early process that precedes learning and recognition. So, by the time an item is recognized, its cortical representation might have already been adjusted according to whether it relates to ongoing reality. Imaging studies have shown that, in addition to the anterior limbic system, different components of the basal ganglia are activated when healthy subjects perform a task that elicits confabulation in patients. This observation has led to the proposal that monitoring of ongoing reality in thought might be related to the brain's reward system. Confabulation — the production of fictitious stories — has puzzled clinicians for over a century. Recent studies have singled out spontaneous confabulations as a distinct disorder that is characterized by an inability to adapt thought and behaviour to ongoing reality, so that patients act according to presently inappropriate memories. Lesions that lead people to confabulate always involve anterior limbic structures. Studies on healthy subjects and on patients with lesions of this type indicate that the orbitofrontal cortex, through subcortical connections, suppresses presently irrelevant memories even before their content is consciously recognized. The studies indicate that the monitoring of ongoing reality in thought might be a capacity of the brain's reward system.

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. •Learning and offline consolidation of mirror-drawing skills are evaluated.•EEG resting-state predicts learning but not offline consolidation.•Modulations of resting state are apparent at the alpha-band in left parietal areas.•Alpha-band resting-state provides the optimal neural resources for upcoming tasks.

Several studies have shown that maintaining in memory some attributes of speech, such as the content or pitch of an interlocutor’s message, is markedly reduced in the presence of background sounds made of spectrotemporal variations. However, experimental paradigms showing this interference have only focused on one attribute of speech at a time, and thus differ from real-life situations in which several attributes have to be memorized and maintained simultaneously. It is possible that the interference is even greater in such a case and can occur for a broader range of background sounds. We developed a paradigm in which participants had to maintain the content, pitch and speaker size of auditorily presented speech information and used various auditory distractors to generate interference. We found that only distractors with spectrotemporal variations impaired the detection, which shows that similar interference mechanisms occur whether there are one or more speech attributes to maintain in memory. A high percentage of false alarms was observed with these distractors, suggesting that spectrotemporal variations not only weaken but also modify the information maintained in memory. Lastly, we found that participants were unaware of the interference. These results are similar to those observed in the visual modality.

Objectives: To report an unusual cause of intrathecal drug delivery failure in baclofen pump device. Study design: A case report of an SCI patient treated with intrathecal baclofen, presenting a drug withdrawal. Setting: Regional spinal cord injuries centre in Geneva (Switzerland). Methods: We present a case of a 38-year-old male with complete T9 spastic paraplegia for 15 years, treated with intrathecal baclofen for 11 years. He recently presented to our centre with a spastic hypertonic episode, associated with rhabdomyolysis. Results: Standard investigations were unrevealing. However, a CT scan performed after injecting a radio-opaque solution by the side port of the pump, showed an unexpected catheter migration into the subdural space. Surgical revision reversed withdrawal symptoms. Conclusions: Subdural catheter migration must be considered in the differential diagnosis of intrathecal drug delivery system failures. We recommend the use of the CT scan after contrast injection, to detect the localization of the distal catheter tip and confirm the normal diffusion into the subarachnoid space.