Search results for "ORIENTATION"
showing 10 items of 1041 documents
Mushroom bodies enhance initial motor activity in Drosophila.
2009
The central body (or central complex, CCX) and the mushroom bodies (MBs) are brain structures in most insect phyla that have been shown to influence aspects of locomotion. The CCX regulates motor coordination and enhances activity while MBs have, thus far, been shown to suppress motor activity levels measured over time intervals ranging from hours to weeks. In this report, we investigate MB involvement in motor behavior during the initial stages (15 minutes) of walking in Buridan's paradigm. We measured aspects of walking in flies that had MB lesions induced by mutations in six different genes and by chemical ablation. All tested flies were later examined histologically to assess MB neuroan…
Improving spatial functioning in children with cerebral palsy using computerized and traditional game tasks.
2003
To examine the effectiveness of combining virtual environment (VE) instruction with additional desk-top tasks, based on the Luria-Vygotsky methodology, for spatial remediation in children having complex motor disabilities restricting movement.In Experiment 1, from among children attending for residential rehabilitation, an experimental subgroup had additional spatial training using a VE and corresponding desk-top models. All children were tested at the start and end of training, using four spatial tests. In Experiment 2, larger groups of children (pair-matched for initial performance) were given the same training as in Experiment 1, but experimentals received both VE-based training and supp…
Effects of dopamine antagonists with different receptor blockade profiles on morphine-induced place preference in male mice.
2001
The effects of dopamine (DA) antagonists with different selectivity for the DA receptors (SCH 23390, 0.5, 0.25, 0.125 mg/kg; haloperidol, 0.2, 0.1 mg/kg; raclopride, 1.2, 0.6, 0.3 mg/kg; risperidone, 0.4, 0.2, 0.1 mg/kg; U-99194A maleate, 40, 20 mg/kg; clozapine, 2.5, 1.25, 0.625 mg/kg) on the acquisition of place conditioning and morphine-induced conditioned place preference (CPP) were explored in male mice. Morphine (40 mg/kg) produced CPP while SCH 23390, haloperidol and clozapine (highest dose) and risperidone (lowest dose) produced conditioned place aversion (CPA). Raclopride and U-99194A maleate did not produce CPP or CPA. Morphine-induced CPP was reversed by the administration of SCH…
Being an optimist or a pessimist and its relationship with morning cortisol release and past life review in healthy older people
2017
Investigate the relationship between optimism and pessimism and the cortisol awakening response (CAR) and past life review in healthy older people.76 older volunteers summarised their lives, highlighting the most important events, impressions and experiences. Cortisol saliva samples were collected on two consecutive weekdays. High and low optimism and pessimism groups were computed by mean split.Percentages of positive (PE) and negative events (NE) and positive (PCE) and negative cognitions and emotions (NCE) were obtained. Optimism and pessimism were measured with the Life Orientation Test Revised. The areas under the curve with respect to the ground and with respect to the increase were c…
Three-dimensional imaging of cardiac mass lesions by transesophageal echocardiographic computed tomography.
1994
Three-dimensional echocardiography is a new imaging technique that allows more realistic visualization of cardiac morphology. This study presents data about the diagnostic potentials of this technique concerning cardiac mass lesions, as well as its feasibility in clinical application. After the conventional investigation, multiple cross-sectional images were obtained during automatic forward advancement of a monoplane transducer mounted on a transesophageal probe. Three-dimensional reconstruction and volume determination were performed off line. Twenty-four patients were studied. In 14 cases results of echocardiographic computed tomography (echo-CT) were compared with those of monoplane/bip…
Effects of sulpiride on the orienting movement evoked By acoustic stimulation in the Rat.
2000
Abstract Drugs that selectively block D 2 receptors are known to provoke a rapid cell firing increase followed by A9 and A10 dopaminergic (DA) neuron inactivation (depolarization block). In this study, possible relationships between cell firing rapid increase and specific behavioral effects, linked to sensorimotor integration, were investigated in the rat. To this purpose, with the aid of a video camera apparatus and a frame-by-frame analysis, effects of sulpiride-induced blockade of DA D 2 receptors were analyzed on the orienting movement of the head induced by acoustic stimulation. In a control group of rats, during trials lasting 20 min, latency and duration of head turning (HT) were 186…
Differences in axial segment reorientation during standing turns predict multiple falls in older adults
2011
Author's version of an article in the journal: Gait and Posture. Also available from the publisher at: http://dx.doi.org/10.1016/j.gaitpost.2012.05.013 Background: The assessment of standing turning performance is proposed to predict fall risk in older adults. This study investigated differences in segmental coordination during a 360° standing turn task between older community-dwelling fallers and non-fallers. Methods: Thirty-five older adults age mean (SD) of 71 (5.4) years performed 360° standing turns. Head, trunk and pelvis position relative to the laboratory and each other were recorded using a Vicon motion analysis system. Fall incidence was monitored by monthly questionnaire over the…
Biased postural vertical in humans with hemispheric cerebral lesions.
1998
International audience; This study was aimed at demonstrating the existence of a biased postural vertical in humans with a recent cerebral lesion. The postural vertical of patients and controls was analysed comparatively using a self-regulated balancing task, performed in sitting posture. Patients displayed a quite constant (19/22) contralesional tilt of the postural vertical (mean -2.6 degrees), varying with the severity of their spatial neglect and hemianaethesia. Eight of them showed a pathological contralesional bias (mean -5.5 degrees) as compared to normals. This result indicates an asymmetric process of somatic graviceptive information due to some cerebral lesions. When patients were…
Linking Microstructural Integrity and Motor Cortex Excitability in Multiple Sclerosis
2021
Motor skills are frequently impaired in multiple sclerosis (MS) patients following grey and white matter damage with cortical excitability abnormalities. We applied advanced diffusion imaging with 3T magnetic resonance tomography for neurite orientation dispersion and density imaging (NODDI), as well as diffusion tensor imaging (DTI) in 50 MS patients and 49 age-matched healthy controls to quantify microstructural integrity of the motor system. To assess excitability, we determined resting motor thresholds using non-invasive transcranial magnetic stimulation. As measures of cognitive-motor performance, we conducted neuropsychological assessments including the Nine-Hole Peg Test, Trail Makin…
rTMS evidence of different delay and decision processes in a fronto-parietal neuronal network activated during spatial working memory.
2003
The existence of a specific and widely distributed network for spatial working memory (WM) in humans, involving the posterior parietal cortex and the prefrontal cortex, is supported by a number of neuroimaging studies. We used a repetitive transcranial magnetic stimulation (rTMS) approach to investigate the temporal dynamics and the reciprocal interactions of the different areas of the parieto-frontal network in normal subjects performing a spatial WM task, with the aim to compare neural activity of the different areas in the delay and decision phases of the task. Trains of rTMS at 25 Hz were delivered over the posterior parietal cortex (PPC), the premotor cortex (SFG) and the dorsolateral …