Search results for "Motor activity"
showing 10 items of 486 documents
The role of attention in preschoolers’ working memory
2015
Abstract Recent studies showed that introducing an unfilled delay or a secondary task between encoding and recall reduces recall performance in preschoolers, whereas increasing the attentional demand of this secondary task does not. Based on these results, different authors drew opposing conclusions regarding the use of attention in preschoolers’ memory maintenance. This study aimed to bring further evidence to bear on the issue. In two experiments, recall was reduced when an unfilled delay was introduced before recall, but also when the demand of the concurrent task increased. These effects did not interact with age, although performance improved from 4 to 6 years of age. A third experimen…
Adaptive independent vector analysis for multi-subject complex-valued fMRI data.
2017
Abstract Background Complex-valued fMRI data can provide additional insights beyond magnitude-only data. However, independent vector analysis (IVA), which has exhibited great potential for group analysis of magnitude-only fMRI data, has rarely been applied to complex-valued fMRI data. The main challenges in this application include the extremely noisy nature and large variability of the source component vector (SCV) distribution. New method To address these challenges, we propose an adaptive fixed-point IVA algorithm for analyzing multiple-subject complex-valued fMRI data. We exploited a multivariate generalized Gaussian distribution (MGGD)- based nonlinear function to match varying SCV dis…
Three-dimensional Hall effect accelerometer for recording head movements of freely moving laboratory animals
1991
A Hall effect device was constructed for a measurement of head movements in three spatial dimensions during classical conditioning experiments in cats. A Hall sensor was used to detect movements of a magnetic fragment floating in a small (15 x 15 mm) cube. The magnetic fragment was kept in the centre of the sealed cube with a thin coil spring which was filled with thin oil for damping excessive afteroscillations. A comparison of this device to a commercial accelerometer showed that the accuracy of the Hall device is sufficient for the movement recordings and that the device is sensitive also to slowly accelerating movements. The construction is compact and can be easily mounted, for example…
Individual Differences in Novelty-Seeking and Behavioral Responses to Nicotine: A Review of Animal Studies
2010
Individual differences in the behavioral responses to a novel environment have been proposed as a research tool to predict responsiveness to other behavioral tasks, response to certain events and individual vulnerability to nicotine addiction. In rats and mice, novelty seeking (defined as enhanced specific exploration of novel situations) is a complex behavior confirmed by a large body of neurochemical, endocrinological and behavioral data. We review the main standardized procedures employed to measure the novelty seeking trait in rodents and the ontogeny of this behavior throughout the life-span taking into account that novelty seeking can be permanently modified as a consequence of partic…
Life-Space Mobility in Parkinson's Disease: Associations with Motor and Non-Motor Symptoms.
2019
Background To describe life-space mobility and explore associations of motor and non-motor symptoms with life-space mobility in people with Parkinson’s disease (PD). Methods About 164 community-dwelling persons with PD (mean age 71.6 years, 64.6% men) received a postal survey and a subsequent home visit. Motor assessments included perceived walking difficulties (Walk-12G), mobility (Timed Up and Go test), motor symptoms (UPDRS-III), and freezing of gait (item 3, FOG-Qsa). Non-motor symptoms included depressive symptoms (GDS-15), pain, fatigue (NHP-EN), and global cognition (MoCA). Life-space mobility was assessed with the life-space assessment (LSA). Calculations included composite score (r…
Focal Lesions within the ventral striato-pallidum abolish attraction for male chemosignals in female mice
2014
In rodents, socio-sexual behaviour is largely mediated by chemosensory cues, some of which are rewarding stimuli. Female mice display an innate attraction towards male chemosignals, dependent on the vomeronasal system. This behaviour likely reflects the hedonic value of sexual chemosignals. The anteromedial aspect of the olfactory tubercle, along with its associated islands of Calleja, receives vomeronasal inputs and sexually-dimorphic vasopressinergic innervation. Thus, we hypothesised that this portion of the ventral striato-pallidum, known to be involved in reward processing, might be important for sexual odorant-guided behaviours. In this study, we demonstrate that lesions of this regio…
Behavioural sensitization to repeated sleep deprivation in a mice model of mania.
2008
Sensitization to the effect of stress has been hypothesized as a mechanism to explain episode recurrence and cycle acceleration in bipolar disorder. Naturalistic observations and experimental work in human patients suggested that sleep deprivation can trigger manic episodes of illness. In rats sleep deprivation (SD) with the platform method caused mania-like behaviours thus providing an animal model of mania with face, construct, and predictive validity. In the present study we administered SD or control stress to male CD1 mice following a dose-response protocol based on time of exposure to the experimental conditions (6, 12 or 24 h) and repetition of treatment (three times). SD, but not st…
Postmenopausal women with osteopenia and a healed wrist fracture have reduced physical function and quality of life compared to a matched, healthy co…
2013
Background Fractures lead to reduced physical function and quality of life (QOL), but little is known about postmenopausal women with osteopenia and a healed wrist fracture. The purpose was to evaluate physical function in terms of quadriceps strength, dynamic balance, physical capacity and QOL in postmenopausal women with osteopenia and a healed wrist fracture compared to a matched, healthy control group with no previous fracture. Methods Eighteen postmenopausal women with osteopenia (patients) (mean age 59.1 years, range 54 – 65) and a healed wrist fracture were matched to 18 healthy control subjects on age (mean age 58.5 years, range 51 – 65), height, weight and body mass index (BMI). We…
Drosophila DJ-1 mutants are sensitive to oxidative stress and show reduced lifespan and motor deficits.
2007
Parkinson's disease (PD) is a progressive movement disorder caused by the selective and massive loss of dopaminergic neurons (DA) in the substantia nigra pars compacta (SNc). DJ-1 loss-of-function mutations are involved in inherited early-onset PD forms and result in dysfunction of the oxidative stress response. In mice models, DJ-1 loss provokes sensitivity to oxidative insults but does not produce neurodegeneration. Similar results have been found when analyzing Drosophila mutants for the DJ-1 orthologous genes, DJ-1alpha and DJ-1beta. Here, we report the analysis of two new mutations for the Drosophila DJ-1 genes. Both ubiquitous induction of DJ-1alpha knockdown by RNAi and loss of funct…
Transplanted neural stem/precursor cells instruct phagocytes and reduce secondary tissue damage in the injured spinal cord
2012
Transplanted neural stem/precursor cells possess peculiar therapeutic plasticity and can simultaneously instruct several therapeutic mechanisms in addition to cell replacement. Here, we interrogated the therapeutic plasticity of neural stem/precursor cells after their focal implantation in the severely contused spinal cord. We injected syngeneic neural stem/precursor cells at the proximal and distal ends of the contused mouse spinal cord and analysed locomotor functions and relevant secondary pathological events in the mice, cell fate of transplanted neural stem/precursor cells, and gene expression and inflammatory cell infiltration at the injured site. We used two different doses of neural…