Sleep-wake fragmentation is linked to amyloid beta brain deposition in healthy ageing

Poster (2018, September)

Arousals during sleep are associated with brain tau and amyloid-β burden in healthy older adults

Conference (2018, September)

Motor cortex Transcranial Direct Current Stimulation (tDCS) improves acute stroke visuo-spatial neglect: A series of four case reports

in Brain Stimulation (2018), 11(2), 459-461

Visuospatial neglect remains a relatively misunderstood complication of stroke. Up to 72% of right hemispheric strokes present neglect symptoms, and up to 75% of those patients still suffer at the 3-month ... [more ▼]

Visuospatial neglect remains a relatively misunderstood complication of stroke. Up to 72% of right hemispheric strokes present neglect symptoms, and up to 75% of those patients still suffer at the 3-month mark. This leads to marked increases in dependency, and lower functional outcomes. Transcranial Direct Current Stimulation is a new rehabilitation tool that has been gaining popularity in the last two decades. Current research focuses on subacute or chronic strokes, while stimulating the posterior parietal cortex (PPC), and seems to have positive effects on visuospatial neglect. [less ▲]

Do evoked potentials contribute to the functional follow-up and clinical prognosis of multiple sclerosis?

in Acta Neurologica Belgica (2017)

The clinical variability and complexity of multiple sclerosis (MS) challenges the individual clinical course prognostication. This study aimed to find out whether multimodal evoked potentials (EP ... [more ▼]

The clinical variability and complexity of multiple sclerosis (MS) challenges the individual clinical course prognostication. This study aimed to find out whether multimodal evoked potentials (EP) correlate with the motor components of multiple sclerosis functional composite (MSFCm) and predict clinically relevant motor functional deterioration. One hundred MS patients were assessed at baseline (T0) and about 7.5 years later (T1), with visual, somatosensory and motor EP and rated on the Expanded Disability Status Scale (EDSS) and the MSFCm, including the 9 Hole Peg Test and the Timed 25 Foot Walk (T25FW). The Spearman correlation coefficient (rS) was used to evaluate the cross-sectional and longitudinal relationship between EP Z scores and clinical findings. The predictive value of baseline electrophysiological data for clinical worsening (EDSS, 9-HPT, T25FW, MSFCm) during follow-up was assessed by logistic regression analysis. Unlike longitudinal correlations, cross-sectional correlations between EP Z scores and clinical outcomes were all significant and ranged between 0.22 and 0.67 (p\0.05). The global EP Z score was systematically predictive of EDSS and MSFCm worsening over time (all p\0.05). EP latency was a better predictor than amplitude, although weaker than latency and amplitude aggregation in the global EP Z score. The study demonstrates that EP numerical scores can be used for motor function monitoring and outcome prediction in patients with MS. [less ▲]

Resting-state Network-specific Breakdown of Functional Connectivity during Ketamine Alteration of Consciousness in Volunteers

in Anesthesiology (2016), 125(5), 873-878

Background: Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control ... [more ▼]

Background: Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control network, salience network (SALn), auditory network, sensorimotor network (SMn), and visual network sustain mentation. Ketamine modifies consciousness differently from other agents, producing psychedelic dreaming and no apparent interaction with the environment. The authors used functional magnetic resonance imaging to explore ketamine-induced changes in RSNs connectivity. Methods: Fourteen healthy volunteers received stepwise intravenous infusions of ketamine up to loss of responsiveness. Because of agitation, data from six subjects were excluded from analysis. RSNs connectivity was compared between absence of ketamine (wake state [W1]), light ketamine sedation, and ketamine-induced unresponsiveness (deep sedation [S2]). Results: Increasing the depth of ketamine sedation from W1 to S2 altered DMn and SALn connectivity and suppressed the anticorrelated activity between DMn and other brain regions. During S2, DMn connectivity, particularly between the medial prefrontal cortex and the remaining network (effect size β [95% CI]: W1 = 0.20 [0.18 to 0.22]; S2 = 0.07 [0.04 to 0.09]), and DMn anticorrelated activity (e.g., right sensory cortex: W1 = −0.07 [−0.09 to −0.04]; S2 = 0.04 [0.01 to 0.06]) were broken down. SALn connectivity was nonuniformly suppressed (e.g., left parietal operculum: W1 = 0.08 [0.06 to 0.09]; S2 = 0.05 [0.02 to 0.07]). Executive control networks, auditory network, SMn, and visual network were minimally affected. Conclusions: Ketamine induces specific changes in connectivity within and between RSNs. Breakdown of frontoparietal DMn connectivity and DMn anticorrelation and sensory and SMn connectivity preservation are common to ketamine and propofol-induced alterations of consciousness. [less ▲]

Le syndrome de De Morsier : une cause congénitale méconnue d'hypopituitarisme

in Annales d'Endocrinologie : 33ème congrès de la Société Française d'Endocrinologie (2016, October)

Circadian dynamics in measures of cortical excitation and inhibition balance

in Scientific Reports (2016), 6:33661

Sleep deprivation affects brain global cortical responsivenes

Conference (2016, June 15)

Seasonal variation in human COGNITIVE brain responses

Poster (2016, June)

The impact of dopaminergic genes on inhibitory processes and cognitive control.

Poster (2016, March 18)