Search results for " Movement"
showing 10 items of 1376 documents
Amusic does not mean unmusical: Beat perception and synchronization ability despite pitch deafness
2013
Pitch deafness, the most commonly known form of congenital amusia, refers to a severe deficit in musical pitch processing (i.e., melody discrimination and recognition) that can leave time processing--including rhythm, metre, and "feeling the beat"--preserved. In Experiment 1, we show that by presenting musical excerpts in nonpitched drum timbres, rather than pitched piano tones, amusics show normal metre recognition. Experiment 2 reveals that body movement influences amusics' interpretation of the beat of an ambiguous drum rhythm. Experiment 3 and a subsequent exploratory study show an ability to synchronize movement to the beat of popular dance music and potential for improvement when give…
Unique astrocyte ribbon in adult human brain contains neural stem cells but lacks chain migration
2003
The subventricular zone (SVZ) is a principal source of adult neural stem cells in the rodent brain, generating thousands of olfactory bulb neurons every day. If the adult human brain contains a comparable germinal region, this could have considerable implications for future neuroregenerative therapy. Stem cells have been isolated from the human brain, but the identity, organization and function of adult neural stem cells in the human SVZ are unknown. Here we describe a ribbon of SVZ astrocytes lining the lateral ventricles of the adult human brain that proliferate in vivo and behave as multipotent progenitor cells in vitro. This astrocytic ribbon has not been observed in other vertebrates s…
Thalamic infarctions cause side-specific suppression of vestibular cortex activations.
2005
H2O15-PET was performed during caloric vestibular stimulation of the right and left external ears in eight right-handed patients with acute unilateral infarctions or haemorrhages of the posterolateral thalamus (four right, four left). The posterolateral thalamus is the relay station for ipsi- and contralateral ascending vestibular input to the multiple multisensory vestibular cortex areas. The aim of this study was to evaluate the differential effects of unilateral vestibular thalamic lesions on thalamo-cortical projections, right hemispheric dominance and reciprocal inhibitory visual-vestibular interaction, as well as perceptual and ocular motor consequences during caloric irrigation. The …
Anatomical correlates of ocular motor deficits in cerebellar lesions
2009
Humans are able to stabilize the images of moving targets on the retina by means of smooth pursuit eye movements. After the pontine level, all smooth pursuit pathways pass through the cerebellum. Previous animal studies gave evidence that two specific lesion sites within the cerebellum cause smooth pursuit disorders: those of the flocculus/paraflocculus and the vermis including lobule VI, VII, the uvula and the deep cerebellar nuclei. To date, there have been only a few lesion studies in patients with smooth pursuit disorders that do not allow direct comparison with a control group. In the present study, new lesion mapping techniques determined which cerebellar structures were involved in p…
Static and dynamic body image in bulimia nervosa: mental representation of body dimensions and biological motion patterns.
2006
The aim of the present study was to find out whether in bulimia nervosa the perceptual component of a disturbed body image is restricted to the overestimation of one's own body dimensions (static body image) or can be extended to a misperception of one's own motion patterns (dynamic body image).Participants with bulimia nervosa (n = 30) and normal controls (n = 55) estimated their body dimensions by means of a photo distortion technique and their walking patterns using a biological motion distortion device.Not only did participants with bulimia nervosa overestimate their own body dimensions, but also they perceived their own motion patterns corresponding to a higher BMI than did controls. S…
Central action of cinnarizine and flunarizine: A saccadic eye movement study
1994
The mechanism of action of flunarizine (FZ) and cinnarizine (CZ) on the CNS is not fully understood. Computer analysis of saccadic eye movements (SEM) provides a sensitive and objective method for evaluating drug effect on the function of specific brain structures. This study aimed to assess the effect of a single oral dose of FZ (20 mg) and CZ (150 mg) on CNS function by means of computer analysis of SEM. Ten healthy volunteers were studied according to a double-blind, cross-over, placebo-controlled design. Peak saccadic velocity (PSV), which is related to the function of a specific group of burst neurons located in the brain stem, was significantly reduced by FZ. No significant effect of …
Similar planning strategies for whole-body and arm movements performed in the sagittal plane
2003
The present paper looks for kinematic similarities between whole-body and arm movements executed in the sagittal plane. Eight subjects performed sit-to-stand (STS) and back-to-sit (BTS) movements at their preferred speed in the sagittal plane. Kinematics analysis focused on shoulder motion revealed that STS was composed of a straight, forward displacement followed by a curved, upward displacement while BTS was characterized by a curved, downward and straight, backward displacement. Curvature of the upward displacement was significantly greater than the downward one. Analysis of shoulder-velocity profiles showed that movement duration was significantly longer for BTS compared with STS and th…
Immunohistochemical Investigation of Metastasis-Related Chemokines in Deep-Infiltrating Endometriosis and Compromised Pelvic Sentinel Lymph Nodes
2015
Endometriosis is a prevalent benign disease, despite sharing several similarities with malignancies, such as the possibility of lymphatic spread. In malignancies, chemokines play a sovereign role in the process of metastasis. Metastasis-related chemokine axes have not yet been assessed in deep-infiltrating endometriosis (DIE), and this investigation was the aim of our study. The expression of these chemokines was investigated by immunohistochemistry in rectovaginal DIE lesions and in matched pelvic sentinel lymph nodes (PSLNs) of patients with endometriosis (n = 27), and their expression in the eutopic endometrium (EE) of endometriosis-free women (n = 20) was used as controls. Their stainin…
Role of the feedforward command and reafferent information in the coordination of a passing prehension task.
1999
The performances of a deafferented patient and five control subjects have been studied during a self-driven passing task in which one hand has to grasp an object transported by the other hand and in a unimanual reach-to-grasp task. The kinematics of the reach and grasp components and the scaling of the grip aperture recorded for the self-driven passing task were very similar in controls and the deafferented subject (GL). In contrast, for the unimanual task when vision was absent, GL's coordination between reaching and grasping was delayed in space and time compared with the control subjects. In addition, frequent reopening of the grip was observed in GL during the final closure phase of the…
Corrective loops involved in fast aiming movements: effect of task and environment
1998
In daily living, we continuously interact with our environment. This environment is rarely stable and living beings show remarkable adaptive capacities. When we reach for an object, it is necessary to localize the position of this object with respect to our own body before programming an adequate arm movement. If the target remains stable, the programmed movement brings the hand near the target. However, what happens when the target suddenly jumps to another position in space? The aim of this work was to investigate how rapid aiming movements are corrected when the target is displaced close to movement onset. Our results reveal that rapid movements can be modified and that the efficiency of…