Learn More
Intracellular recordings were obtained from medial vestibular nuclei neurones (MVNn) in guinea-pig brainstem slices. Two main distinct neuronal classes were encountered. Type A MVNn (32.3%) were characterized by a broad action potential followed by a deep single afterhyperpolarization, a transient A-like rectification, and a single range of firing in(More)
In the preceding paper, medial vestibular nuclei neurones (MVNn) were shown to belong to two main classes, A MVNn and B MVNn, depending on their membrane properties in brainstem slices. In the following study we attempted to confirm this segregation by studying some of the ionic conductances that these cells are endowed with. Type A MVNn demonstrated small(More)
There is considerable evidence from studies on cats and monkeys that several cortical areas such as area 2v at the tip of the intraparietal sulcus, area 3av in the sulcus centralis, the parietoinsular vestibular cortex adjacent to the posterior insula (PIVC) and area 7 in the inferior parietal lobule are involved in the processing of vestibular information.(More)
The horizontal vestibulo-ocular reflex (HVOR) in the alert guinea-pig elicited by sinusoidal rotations and by velocity steps was studied with scleral search coil measurement between 3 and 7 days (short term) and between 35 and 160 days (long term) after hemilabyrinthectomy. Animals of the short-term group were always tested after spontaneous nystagmus in(More)
Previously we demonstrated a stereotyped resting posture of the head-neck arrangement in a number of vertebrates: the cervical vertebral column is oriented vertically to form one portion of the partial S-shaped configuration of the entire spine. The present investigation quantified the various strategies of head-neck movements employed by different(More)
Vestibular compensation for the static and dynamic disorders induced by unilateral labyrinthectomy is a good model of plasticity in the central nervous system. After the lesion, the static deficits generally disappear in a few days, whereas recuperation of the dynamic, vestibular-related synergies is much slower and merely partial. The goal of this article(More)
1. Neuronal activity was investigated in the left superior vestibular nucleus (SVN), lateral vestibular nucleus (LVN), and rostral part of the medial vestibular nucleus (MVN) in the alert guinea pig after a unilateral (left) labyrinthectomy was performed. Vestibular neurons were recorded either immediately (just-postoperative group, n = 6) or 1 wk after(More)
This biomechanical investigation quantified the range of motion of the different articulations of the head-neck ensemble in man, monkeys, cats, rabbits and guinea pigs. Radiography and dissections were used to establish the degrees of freedom of the system. The erect posture and rigidity of the cervical spine in mammalian vertebrates are possible because(More)
The postural instability of patients with vestibular loss (11 with bilateral and 101 with unilateral vestibular loss) at different times following the lesion was investigated by means of posturography and compared to healthy subjects. In addition, subjects submitted to galvanic vestibular stimulation were also studied to compare their postural performances(More)
The aim of this study was to determine how context and on-line sensory information are combined to control posture in seated subjects submitted to high-jerk, passive linear accelerations. Subjects were seated with eyes closed on a servo-controlled linear sled. They were asked to relax and received brief accelerations either sideways or in the fore-aft(More)