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During sleep, sensory stimuli rarely trigger a behavioral response or conscious perception. However, it remains unclear whether sleep inhibits specific aspects of sensory processing, such as feedforward or feedback signaling. Here, we presented auditory stimuli (for example, click-trains, words, music) during wakefulness and sleep in patients with epilepsy, while recording neuronal spiking, microwire local field potentials, intracranial electroencephalogram and polysomnography. Auditory stimuli induced robust and selective spiking and high-gamma (80–200 Hz) power responses across the lateral temporal lobe during both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Sleep only moderately attenuated response magnitudes, mainly affecting late responses beyond early auditory cortex and entrainment to rapid click-trains in NREM sleep. By contrast, auditory-induced alpha–beta (10–30 Hz) desynchronization (that is, decreased power), prevalent in wakefulness, was strongly reduced in sleep. Thus, extensive auditory responses persist during sleep whereas alpha–beta power decrease, likely reflecting neural feedback processes, is deficient. More broadly, our findings suggest that feedback signaling is key to conscious sensory processing.Intracortical recordings in humans reveal that auditory stimulation during sleep induces robust spiking and high-gamma responses, whereas alpha–beta desynchronization—likely reflecting neural feedback processes—is reduced compared to wakefulness.

Despite its ubiquitous use in medicine, and extensive knowledge of its molecular and cellular effects, how anesthesia induces loss of consciousness (LOC) and affects sensory processing remains poorly understood. Specifically, it is unclear whether anesthesia primarily disrupts thalamocortical relay or intercortical signaling. Here we recorded intracranial electroencephalogram (iEEG), local field potentials (LFPs), and single-unit activity in patients during wakefulness and light anesthesia. Propofol infusion was gradually increased while auditory stimuli were presented and patients responded to a target stimulus until they became unresponsive. We found widespread iEEG responses in association cortices during wakefulness, which were attenuated and restricted to auditory regions upon LOC. Neuronal spiking and LFP responses in primary auditory cortex (PAC) persisted after LOC, while responses in higher-order auditory regions were variable, with neuronal spiking largely attenuated. Gamma power induced by word stimuli increased after LOC while its frequency profile slowed, thus differing from local spiking activity. In summary, anesthesia-induced LOC disrupts auditory processing in association cortices while relatively sparing responses in PAC, opening new avenues for future research into mechanisms of LOC and the design of anesthetic monitoring devices.

Purpose Neurosurgical ablative procedures, such as cordotomy and cingulotomy, are often considered irreversible and destructive but can provide an effective and individualized solution for cancer-related refractory pain, when all other approaches have been unsuccessful. This paper provides an in-depth exploration of a novel approach to managing refractory cancer pain. It involves an interdisciplinary team led by a neurosurgeon at a renowned national referral center. Methods a retrospective analysis of the medical records of all sequential patients who underwent their initial evaluation at our interdisciplinary refractory cancer pain clinic from February 2017 to January 2023. Results A total of 207 patients were examined in the clinic for a first visit during the study period. All patients were referred to the clinic due to severe pain that was deemed refractory by the referring physician. The mean age was 61 ± 12.3 years, with no significant sex difference ( P  = 0.58). The mean ECOG Performance Status score was 2.35. Conservative measures had not yet been exhausted in 28 patients (14%) and 9 patients were well controlled (4%). Neurosurgical ablative procedures were recommended for 151 (73%) of the patients. Sixty-six patients (32%) eventually underwent the procedure. 91 patients (44%) received a negative recommendation for surgery. Thirty-five patients (17%) were referred for further invasive procedures at the pain clinic. Conclusion An Interdisciplinary cooperation between palliative care specialists, pain specialists, and neurosurgeons ensures optimal patient selection and provides safe and effective neurosurgery for the treatment of refractory cancer-related pain.

Background Spinal cord stimulation (SCS) is an accepted surgical treatment for neuropathic pain in failed back syndrome or complex regional pain syndrome. However, even in the best selected surgical cases the predictors of adequate pain control are not well defined. The aim of this study was to identify predictors of outcome in patients who underwent SCS in our center. Methods We performed a retrospective analysis of our neurosurgical database for patients who underwent SCS over the last 8 years in an attempt to identify factors predictive of outcome. Results Forty-one patients underwent implantation of epidural electrodes, 34 patients had a successful stimulation trial and received permanent devices. Nine patients experienced a late failure at a median time of 7.8 months (range, 4.5–19 months) after implantation. Age was significantly associated with outcome. Younger patients had a significantly lower rate of treatment failure, and none of the patients above 65 years had a successful long-term outcome. Conclusions Our results suggest that younger age is associated with greater long-term effectiveness of spinal cord stimulation and therefore age may influence the success of SCS therapy with older patients having a greater tendency to failure. Earlier intervention may be beneficial in these chronic pain patients.

Resolving approach-avoidance conflicts relies on encoding motivation outcomes and learning from past experiences. Accumulating evidence points to the role of the Medial Temporal Lobe (MTL) and Medial Prefrontal Cortex (mPFC) in these processes, but their differential contributions have not been convincingly deciphered in humans. We detect 310 neurons from mPFC and MTL from patients with epilepsy undergoing intracranial recordings and participating in a goal-conflict task where rewards and punishments could be controlled or not. mPFC neurons are more selective to punishments than rewards when controlled. However, only MTL firing following punishment is linked to a lower probability for subsequent approach behavior. mPFC response to punishment precedes a similar MTL response and affects subsequent behavior via an interaction with MTL firing. We thus propose a model where approach-avoidance conflict resolution in humans depends on outcome value tagging in mPFC neurons influencing encoding of such value in MTL to affect subsequent choice. Optimizing approach-avoidance behavior calls for neural encoding of related motivation outcomes. Here, the authors show that behavioral choice under conflict relies on differential neuronal firing patterns after punishment, in which mPFC neurons decode the outcome’s value and MTL neurons follow by reducing subsequent approach.

Background The introduction of Onyx has led us to adopt a new treatment approach for brain arteriovenous malformation (AVM), using endovascular embolization with Onyx as the first line treatment with a curative intent. The aim of the present report is to evaluate our results using this strategy, with special emphasis on angiographic characteristics affecting treatment risks and success rates. Methods From October 2006 to December 2009, 92 consecutive patients harboring brain AVM were treated with Onyx during 177 procedures. Results Endovascular treatments were completed in 68 out of 92 patients. Median number of procedures was two. Complete obliteration using embolization exclusively was achieved in 25 patients, resulting in a 37 % cure rate in patients who concluded treatments (25/68), and 27 % in the cohort. In Spetzler-Martin grades 1 & 2 AVMs, complete obliteration was achieved in 48 % of the cases. Complete obliteration rates were significantly higher in lesions with superficial big feeding arteries. There were 15 bleeding complications during 177 embolization sessions (8.4 % per procedure); seven cases resolved in less than 3 months. Permanent disability rate was 6.5 %; mortality rate was 2.2 %. Bleeding was related to the use of the microcatheter/guidewire in six cases and to the use of the embolization material in nine, the amount of Onyx injected was significantly higher in those nine cases. Conclusions Embolization of brain AVM using Onyx and detachable tip microcatheters results in a relatively high rate of complete obliteration. Angioarchitecture of the lesion can predict treatment success. Higher amounts of Onyx injected per session increase the bleeding risk.

Interictal epileptiform discharges (IEDs) such as spikes and sharp waves represent pathological electrophysiological activities occurring in epilepsy patients between seizures. IEDs occur preferentially during non-rapid eye movement (NREM) sleep and are associated with impaired memory and cognition. Despite growing interest, most studies involving IED detections rely on visual annotations or employ simple amplitude threshold approaches. Alternatively, advanced computerized detection methods are not standardized or publicly available. To address this gap, we introduce a novel dataset comprising multichannel intracranial electroencephalography (iEEG) data recorded at two medical centers during overnight sleep with IED annotations performed by expert neurologists. Utilizing these annotations to train machine learning models via a gradient-boosting algorithm, we demonstrate automated IED detection with high precision (94.4%) and sensitivity (94.3%) that can generalize across individuals and surpass performance of a leading commercial software. The dataset featuring multi-channel annotations with sub-second resolution including hippocampus and medial temporal lobe (MTL) regions is made publicly available, together with the detection algorithm, to advance research on detection methodology, epilepsy, sleep, and cognition.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Background The surgical treatment of brain tumors has developed over time, offering customized strategies for patients and their specific lesions. One of the most recent advances in pediatric neuro-oncological surgery is laser interstitial thermal therapy (LITT). However, its effectiveness and indications are still being evaluated. The aim of this work is to review the current literature on LITT for pediatric low-grade gliomas (pLGG) and evaluate our initial results in this context. Methods We retrospectively reviewed our pediatric neurosurgery database for patients who received LITT treatment between November 2019 and December 2023. We collected data on the indications for LITT, technical issues during the procedure, and clinical and radiological follow-up. Results Three patients underwent 5 LITT procedures for pLGG. The lesion was thalamo-peduncular in one patient, cingulate in one, and deep parietal in one patient. Two patients had a previous open resection done and were diagnosed with pLGG. One patient underwent a stereotaxic biopsy during the LITT procedure that was non-diagnostic. The same patient underwent a later open resection of the tumor in the cingulate gyrus. There were no surgical complications and all patients were discharged home on the first post-operative day. The follow-up period was between 20 and 40 months. Radiological follow-up showed a progressive reduction of the tumor in patients with LGG. Conclusion Laser interstitial thermal therapy is a minimally invasive treatment that shows promise in treating deep-seated pLGG in children. The treatment has demonstrated a reduction in tumor volume, and the positive results continue over time. LITT can be used as an alternative treatment for tumors located in areas that are difficult to access surgically or in cases where other standard treatment options have failed.

Background Flow diverters are used to treat complex aneurysms that are not amenable to coiling. The aim of the present work was to retrospectively evaluate our experience with the Silk flow diverter. Technical nuances and complications are specifically discussed. Methods Retrospectively data was collected on patients treated with Silk between October 2008 and October 2013. Results Sixty patients harboring 67 aneurysms were treated using the Silk. Fifteen aneurysms were located in the posterior circulation and 52 in the anterior. A good angiographic result was achieved in 88 % (53/60) of the aneurysms available for imaging follow-up. There were ten treatment-related complications, 80 % were ischemic. Risk of complications increased with aneurysm size and in aneurysms of the posterior circulation. Conclusions Silk flow diverters are a good treatment option for aneurysms of the anterior circulation. Additional stents may be required in specific cases due to the Silk’s low radial resistance. Treatment of giant fusiform aneurysms of the posterior circulation with Silk flow diverters is associated with a high rate of severe complications.