Background: Line-field confocal optical coherence tomography (LC-OCT) is an imaging technique providing non-invasive "optical biopsies" with an isotropic spatial resolution of ∼1 μm and deep penetration until the dermis. Analysis of obtained images is classically performed by experts, thus requiring long and fastidious training and giving operator-dependent results. In this study, the objective was to develop a new automated method to score the quality of the dermal matrix precisely, quickly, and directly from in vivo LC-OCT images.
View Article and Find Full Text PDFWhite matter disorders of the central nervous system (CNS), such as multiple sclerosis (MS), lead to failure of nerve conduction and long-lasting neurological disabilities affecting a variety of sensory and motor systems, including vision. While most disease-modifying therapies target the immune and inflammatory response, the promotion of remyelination has become a new therapeutic avenue to prevent neuronal degeneration and promote recovery. Most of these strategies have been developed in short-lived rodent models of demyelination, which spontaneously repair and do not reflect the size, organization, and biology of the human CNS.
View Article and Find Full Text PDFAppropriate gaze interaction is essential for primate social life. Prior studies have suggested the involvement of the amygdala in processing eye cues but its role in gaze behavior during live social exchanges remains unknown. We recorded the activity of neurons in the amygdala of two monkeys as they engaged in spontaneous visual interactions.
View Article and Find Full Text PDFObjective: Hair greying (i.e. canitie) is a physiological process occurring with the loss of melanin production and deposition within the hair shafts.
View Article and Find Full Text PDFPsychopharmacology (Berl)
October 2018
The article Dual contributions of noradrenaline to behavioural flexibility and motivation written by Caroline I. Jahn, Sophie Gilardeau, Chiara Varazzani, Bastien Blain, Jerome Sallet, Mark E. Walton, Sebastien Bouret was originally published electronically on the publisher's internet portal.
View Article and Find Full Text PDFPsychopharmacology (Berl)
September 2018
Introduction: While several theories have highlighted the importance of the noradrenergic system for behavioral flexibility, a number of recent studies have also shown a role for noradrenaline in motivation, particularly in effort processing. Here, we designed a novel sequential cost/benefit decision task to test the causal influence of noradrenaline on these two functions in rhesus monkeys.
Methods: We manipulated noradrenaline using clonidine, an alpha-2 noradrenergic receptor agonist, which reduces central noradrenaline levels and examined how this manipulation influenced performance on the task.
Background: Behavioral studies in both human and animals generally converge to the dogma that multisensory integration improves reaction times (RTs) in comparison to unimodal stimulation. These multisensory effects depend on diverse conditions among which the most studied were the spatial and temporal congruences. Further, most of the studies are using relatively simple stimuli while in everyday life, we are confronted to a large variety of complex stimulations constantly changing our attentional focus over time, a modality switch that can impact on stimuli detection.
View Article and Find Full Text PDFOcular saccades bringing the gaze toward the straight-ahead direction (centripetal) exhibit higher dynamics than those steering the gaze away (centrifugal). This is generally explained by oculomotor determinants: centripetal saccades are more efficient because they pull the eyes back toward their primary orbital position. However, visual determinants might also be invoked: elements located straight-ahead trigger saccades more efficiently because they receive a privileged visual processing.
View Article and Find Full Text PDFMotivation determines multiple aspects of behavior, including action selection and energization of behavior. Several components of the underlying neural systems have been examined closely, but the specific role of the different neuromodulatory systems in motivation remains unclear. Here, we compare directly the activity of dopaminergic neurons from the substantia nigra pars compacta and noradrenergic neurons from the locus coeruleus in monkeys performing a task manipulating the reward/effort trade-off.
View Article and Find Full Text PDF