100 research outputs found
The web of laughter: frontal and limbic projections of the anterior cingulate cortex revealed by cortico-cortical evoked potential from sites eliciting laughter
According to an evolutionist approach, laughter is a multifaceted behaviour
affecting social, emotional, motor and speech functions. Albeit previous
studies have suggested that high-frequency electrical stimulation (HF-ES)
of the pregenual anterior cingulate cortex ( pACC) may induce bursts of
laughter—suggesting a crucial contribution of this region to the cortical con-
trol of this behaviour—the complex nature of laughter implies that outward
connections from the pACC may reach and affect a complex network of fron-
tal and limbic regions. Here, we studied the effective connectivity of the
pACC by analysing the cortico-cortical evoked potentials elicited by
single-pulse electrical stimulation of pACC sites whose HF-ES elicited laugh-
ter in 12 patients. Once these regions were identified, we studied their
clinical response to HF-ES, to reveal the specific functional target of pACC
representation of laughter. Results reveal that the neural representation of
laughter in the pACC interacts with several frontal and limbic regions,
including cingulate, orbitofrontal, medial prefrontal and anterior insular
regions—involved in interoception, emotion, social reward and motor be-
haviour. These results offer neuroscientific support to the evolutionist
approach to laughter, providing a possible mechanistic explanation of the
interplay between this behaviour and emotion regulation, speech production
and social interactions.
This article is part of the theme issue ‘Cracking the laugh code: laughter
through the lens of biology, psychology, and neuroscience’
Identification of movement phenotypes from occupational gesture kinematics: Advancing individual ergonomic exposure classification and personalized training
: The identification of personalized preventive strategies plays a major role in contrasting the occurrence of work-related musculoskeletal disorders. This requires the identification of distinct movement patterns within large samples and the attribution of a proper risk level to each identified movement phenotype. We assessed the feasibility of this approach by exploiting wearable inertial measurement units to estimate the whole-body kinematics of 43 healthy participants performing 18 reach-to-manipulate movements, which differed based on the object's position in the space and the type of manipulation required. Through unsupervised clustering, we identified multiple movement phenotypes graded by ergonomic performance. Furthermore, we determined which joints mostly contributed to instantiating the ergonomic differences across clusters, emphasizing the importance of monitoring this aspect during occupational gestures. Overall, our analysis suggests that movement phenotypes can be identified within occupational motor repertoires. Assigning individual performance to specific phenotypes has the potential to inform the development of more effective and tailored interventions
Centrotemporal spikes during NREM sleep: The promoting action of thalamus revealed by simultaneous EEG and fMRI coregistration
Benign childhood epilepsy with centrotemporal spikes (BECTS) has been investigated through EEG\u2013fMRI
with the aim of localizing the generators of the epileptic activity, revealing, in most cases, the activation of
the sensory\u2013motor cortex ipsilateral to the centrotemporal spikes (CTS). In this case report, we investigated
the brain circuits hemodynamically involved by CTS recorded during wakefulness and sleep in one boy with
CTS and a language disorder but without epilepsy. For this purpose, the patient underwent EEG\u2013fMRI
coregistration. During the \u201cawake session\u201d, fMRI analysis of right-sided CTS showed increments of BOLD signal
in the bilateral sensory\u2013motor cortex. During the \u201csleep session\u201d, BOLD increments related to right-sided
CTS were observed in a widespread bilateral cortical\u2013subcortical network involving the thalamus, basal
ganglia, sensory\u2013motor cortex, perisylvian cortex, and cerebellum.
In this patient, who fulfilled neither the diagnostic criteria for BECTS nor that for electrical status epilepticus
in sleep (ESES), the transition from wakefulness to sleep was related to the involvement of a widespread
cortical\u2013subcortical network related to CTS. In particular, the involvement of a thalamic\u2013perisylvian neural
network similar to the one previously observed in patients with ESES suggests a common sleep-related
network dysfunction even in cases with milder phenotypes without seizures. This finding, if confirmed in a
larger cohort of patients, could have relevant therapeutic implication
An integrative, multiscale view on neural theories of consciousness.
How is conscious experience related to material brain processes? A variety of theories aiming to answer this age-old question have emerged from the recent surge in consciousness research, and some are now hotly debated. Although most researchers have so far focused on the development and validation of their preferred theory in relative isolation, this article, written by a group of scientists representing different theories, takes an alternative approach. Noting that various theories often try to explain different aspects or mechanistic levels of consciousness, we argue that the theories do not necessarily contradict each other. Instead, several of them may converge on fundamental neuronal mechanisms and be partly compatible and complementary, so that multiple theories can simultaneously contribute to our understanding. Here, we consider unifying, integration-oriented approaches that have so far been largely neglected, seeking to combine valuable elements from various theories
Gaslini's tracheal team: preliminary experience after one year of paediatric airway reconstructive surgery
Background: congenital and acquired airway anomalies represent a relatively common albeit challenging problem in a national tertiary care hospital. In the past, most of these patients were sent to foreign Centres because of the lack of local experience in reconstructive surgery of the paediatric airway. In 2009, a dedicated team was established at our Institute. Gaslini's Tracheal Team includes different professionals, namely anaesthetists, intensive care specialists, neonatologists, pulmonologists, radiologists, and ENT, paediatric, and cardiovascular surgeons. The aim of this project was to provide these multidisciplinary patients, at any time, with intensive care, radiological investigations, diagnostic and operative endoscopy, reconstructive surgery, ECMO or cardiopulmonary bypass. Aim of this study is to present the results of the first year of airway reconstructive surgery activity of the Tracheal Team.Methods: between September 2009 and December 2010, 97 patients were evaluated or treated by our Gaslini Tracheal Team. Most of them were evaluated by both rigid and flexible endoscopy. In this study we included 8 patients who underwent reconstructive surgery of the airways. Four of them were referred to our centre or previously treated surgically or endoscopically without success in other Centres.Results: Eight patients required 9 surgical procedures on the airway: 4 cricotracheal resections, 2 laryngotracheoplasties, 1 tracheal resection, 1 repair of laryngeal cleft and 1 foreign body removal with cardiopulmonary bypass through anterior tracheal opening. Moreover, in 1 case secondary aortopexy was performed. All patients achieved finally good results, but two of them required two surgeries and most required endoscopic manoeuvres after surgery. The most complex cases were the ones who had already been previously treated.Conclusions: The treatment of paediatric airway anomalies requires a dedicated multidisciplinary approach and a single tertiary care Centre providing rapid access to endoscopic and surgical manoeuvres on upper and lower airways and the possibility to start immediately cardiopulmonary bypass or ECMO.The preliminary experience of the Tracheal Team shows that good results can be obtained with this multidisciplinary approach in the treatment of complicated cases. The centralization of all the cases in one or few national Centres should be considered
An integrative, multiscale view on neural theories of consciousness
How is conscious experience related to material brain processes? A variety of theories aiming to answer this age-old question have emerged from the recent surge in consciousness research, and some are now hotly debated. Although most researchers have so far focused on the development and validation of their preferred theory in relative isolation, this article, written by a group of scientists representing different theories, takes an alternative approach. Noting that various theories often try to explain different aspects or mechanistic levels of consciousness, we argue that the theories do not necessarily contradict each other. Instead, several of them may converge on fundamental neuronal mechanisms and be partly compatible and complementary, so that multiple theories can simultaneously contribute to our understanding. Here, we consider unifying, integration-oriented approaches that have so far been largely neglected, seeking to combine valuable elements from various theories
Melanopsin retinal ganglion cell loss in Alzheimer's disease
Objective Melanopsin retinal ganglion cells (mRGCs) are photoreceptors driving circadian photoentrainment, and circadian dysfunction characterizes Alzheimer disease (AD). We investigated mRGCs in AD, hypothesizing that they contribute to circadian dysfunction. Methods We assessed retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT) in 21 mild-moderate AD patients, and in a subgroup of 16 we evaluated rest-activity circadian rhythm by actigraphy. We studied postmortem mRGCs by immunohistochemistry in retinas, and axons in optic nerve cross-sections of 14 neuropathologically confirmed AD patients. We coimmunostained for retinal amyloid \u3b2 (A\u3b2) deposition and melanopsin to locate mRGCs. All AD cohorts were compared with age-matched controls. Results We demonstrated an age-related optic neuropathy in AD by OCT, with a significant reduction of RNFL thickness (p = 0.038), more evident in the superior quadrant (p = 0.006). Axonal loss was confirmed in postmortem AD optic nerves. Abnormal circadian function characterized only a subgroup of AD patients. Sleep efficiency was significantly reduced in AD patients (p = 0.001). We also found a significant loss of mRGCs in postmortem AD retinal specimens (p = 0.003) across all ages and abnormal mRGC dendritic morphology and size (p = 0.003). In flat-mounted AD retinas, A\u3b2 accumulation was remarkably evident inside and around mRGCs. Interpretation We show variable degrees of rest-activity circadian dysfunction in AD patients. We also demonstrate age-related loss of optic nerve axons and specifically mRGC loss and pathology in postmortem AD retinal specimens, associated with A\u3b2 deposition. These results all support the concept that mRGC degeneration is a contributor to circadian rhythm dysfunction in AD
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