Search results for "Visuomotor"
showing 10 items of 10 documents
Integration of cognitive allocentric information in visuospatial short-term memory through the hippocampus
2005
Visuospatial short-term memory relies on a widely distributed neocortical network: some areas support the encoding process of the visually acquired spatial information, whereas other ares are more involved in the active maintenance of the encoded information. Recently, in a pointing to remembered targets task, it has been shown in healthy subjects that, for memory delays of 5 s, spatial errors are affected also by cognitive allocentric information, i.e., covert spatial information derived from a pure mental representation. We tested the effect of a lesion of the hippocampus on the accuracy of pointing movements toward remembered targets, with memory delays falling in the 0.5-30 s range. The…
''Motor Resonance Mechanisms Are Preserved In Alzheimer's Disease Patients''
2012
Bisio, A. | Casteran, M. | Ballay, Y. | Manckoundia, P. | Mourey, F. | Pozzo, T.; International audience; ''This study aimed to better characterize the sensorimotor mechanisms underlying motor resonance, namely the relationship between motion perception and movement production in patients suffering from Alzheimer's disease (AD). This work first gives a kinematic description of AD patients' upper limb movements, then it presents a simple paradigm in which a dot with different velocities is moved in front of the participant who is instructed to point to its final position when it stopped. AD patients' actions, as well as healthy elderly participants, were similarly influenced by the dot veloc…
Multiple representations and mechanisms for visuomotor adaptation in young children
2012
International audience; In this study, we utilized transformed spatial mappings to perturb visuomotor integration in 5-yr-old children and adults. The participants were asked to perform pointing movements under five different conditions of visuomotor rotation (from 0° to 180°), which were designed to reveal explicit vs. implicit representations as well as the mechanisms underlying the visual-motor mapping. Several tests allowed us to separately evaluate sensorimotor (i.e., the dynamic dimension of movement) and cognitive (i.e., the explicit representations of target position and the strategies used by the participants) representations of visuo-proprioceptive distortion. Our results indicate…
Reliability, validity and feasibility of nail ultrasonography in psoriatic arthritis
2016
International audience; Objective: To determine the feasibility, reliability and validity of nails ultrasonography in psoriatic arthritis as an outcome measure.Methods: Pilot prospective single-centre study of eight ultrasonography parameters in B mode and power Doppler concerning the distal interphalangeal (DIP) joint, the matrix, the bed and nail plate. Intraobserver and inter-observer reliability was evaluated for the seven quantitative parameters (ICC and kappa). Correlations between ultrasonography and clinical variables were searched to assess external validity. Feasibility was assessed by the time to carry out the examination and the percentage of missing data.Results: Twenty-seven p…
Visuomotor competencies and primary monosymptomatic nocturnal enuresis in prepubertal aged children
2013
Maria Esposito,1 Beatrice Gallai,2 Lucia Parisi,3 Michele Roccella,3 Rosa Marotta,4 Serena Marianna Lavano,4 Giovanni Mazzotta,5 Giuseppina Patriciello,1 Francesco Precenzano,1 Marco Carotenuto1 1Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, Second University of Naples, Italy; 2Unit of Child and Adolescent Neuropsychiatry, University of Perugia, Italy; 3Child Neuropsychiatry, Department of Psychology, University of Palermo, Italy; 4Department of Psychiatry, "Magna Graecia" University of Catanzaro, Catanzaro, Italy; 5Unit of Child and Adolescent Neuropsychiatry, AUSL Umbria 2, Terni, Italy Background: Primary …
Multivariate EEG spectral analysis evidences the functional link between motor and visual cortex during integrative sensorimotor tasks
2012
The identification of the networks connecting brain areas and the understanding of their role in executing complex tasks is a crucial issue in cognitive neuroscience. In this study, specific visuomotor tasks were devised to reveal the functional network underlying the cooperation process between visual and motor regions. Electroencephalography (EEG) data were recorded from twelve healthy subjects during a combined visuomotor task, which integrated precise grip motor commands with sensory visual feedback (VM). This condition was compared with control tasks involving pure motor action (M), pure visual perception (V) and visuomotor performance without feedback (V + M). Multivariate parametric …
Voluntary Imitation in Alzheimer’s Disease Patients
2016
International audience; Although Alzheimer's disease (AD) primarily manifests as cognitive deficits, the implicit sensorimotor processes that underlie social interactions, such as automatic imitation, seem to be preserved in mild and moderate stages of the disease, as is the ability to communicate with other persons. Nevertheless, when AD patients face more challenging tasks, which do not rely on automatic processes but on explicit voluntary mechanisms and require the patient to pay attention to external events, the cognitive deficits resulting from the disease might negatively affect patients' behavior. The aim of the present study was to investigate whether voluntary motor imitation, i.e.…
The effect of transient visual deprivation on motor cortical excitability and motor learning : a pilot study
2016
Castro, Fabio, 2015. The Effect of Transient Visual Deprivation on Motor Cortical Excitability and Motor Learning. University of Jyväskylä, Department of Biology of Physical Activity, Master Thesis in Applied Biomechanics. 86 pp. We devised an experimental protocol to test the hypothesis that if the performer poses attention on the proprioceptive signals, in the form of awareness of the body in space, this could increase the corticospinal excitability and the overall performance. 10 right-handed volunteers were randomly assigned to either a group performing a skill training blindfolded (BLIND) or in normal (NORM) condition. The intervention included a visuomotor task-related skill training …
The effect of paired associative stimulation-induced long-term potentiation-like plasticity on visuomotor learning
2014
Aivojen hermostollisissa rakenteissa ja toiminnassa tapahtuu adaptaatiota motorisen oppimisen seurauksena. Eräs ehdotetuista malleista, johon muutokset voivat perustua on hermoliitoksen voimakkuuden pitkäaikainen tehostuminen eli pitkäkestoinen potentiaa-tio (LTP). Keinotekoisesti LTP:n kaltainen vaikutus voidaan tuottaa parillisella as-sosiatiivisella stimulaatiolla (PAS). Lisäksi tutkimustulokset osoittavat, että PAS voi parantaa tietyn tyyppistä motorista oppimista. Tämän tutkimuksen tarkoituksena on sel-vittää miten PAS:n tuottama LTP:n kaltainen plastisuus vaikuttaa visuomotorisen oppi-misen alkuvaiheeseen. Visuomotorinen oppimistehtävä suoritettiin kolme kertaa PAS:n jälkeen. Oppimist…