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Ulrich Büttner - One of the best experts on this subject based on the ideXlab platform.

  • Multimodal signal integration in vestibular neurons of the primate Fastigial Nucleus.
    Annals of the New York Academy of Sciences, 2003
    Co-Authors: Ulrich Büttner, Stefan Glasauer, L. Glonti, Y. Guan, E. Kipiani, J. F. Kleine, C. Siebold, T. Tchelidze, Andreas Wilden
    Abstract:

    : The rostral Fastigial Nucleus contains vestibular neurons, which presumably are involved in spinal mechanisms (neck, gait, posture) and which are not modulated with individual eye movements. Single-unit recordings in the alert behaving monkey during natural stimulus conditions reveal that virtually all neurons demonstrate integration of several sensory inputs. This applies not only for canal-canal and canal-otolith interaction, but also for otolith-otolith interaction. There is also some evidence that most neurons receive not only an utriculus but also a sacculus input. Furthermore, most neurons also respond to large-field optokinetic stimulation, reflecting visual-vestibular interaction. Neurons are also affected by the head on trunk position, which would allow these neurons to operate in a body-centered rather than a head-centered reference frame. These complex, multisensory features could permit Fastigial Nucleus neurons to rather specifically affect spinal motor functions.

  • Modelling transfer characteristics of vestibular neurons in the Fastigial Nucleus of the behaving monkey on the basis of canal-otolith interaction.
    Neuroreport, 2002
    Co-Authors: Andreas Wilden, J. F. Kleine, Stefan Glasauer, Ulrich Büttner
    Abstract:

    The interaction of vestibular inputs with different dynamic and spatial behavior, i.e., canal-otolith interaction, leads to spatio-temporal convergence. Vestibular neurons in the Fastigial Nucleus often exhibit spatio-temporal convergence. The present report demonstrates that the discharge rates of most vestibular neurons in the primate Fastigial Nucleus can be simulated at different stimulus frequencies and orientations by a simple linear summation of the signals of the semicircular canals and the otoliths. In this way, a number of complex characteristics that depend on frequency, i.e. changing response-vector orientations, large phase changes, absence and presence of spatio-temporal convergence, can be easily explained.

  • Canal-otolith interaction in the Fastigial Nucleus of the alert monkey.
    Experimental brain research, 2001
    Co-Authors: C. Siebold, Stefan Glasauer, L. Glonti, J. F. Kleine, T. Tchelidze, E. Anagnostou, Ulrich Büttner
    Abstract:

    To determine the contribution of the otoliths as well as the horizontal and vertical semicircular canals to the response of "vestibular only" neurons in the rostral Fastigial Nucleus of the alert monkey, we applied natural sinusoidal vestibular stimuli (0.6 Hz; ±15 deg) around different axes. During the experiment the monkey sat erect in a primate chair with the head immobile. Semicircular canal responses were investigated during tilted yaw stimulation around an earth vertical axis. The tilt angle was varied by 30 deg and included the optimal plane for horizontal canal stimulation (15 deg nose down from the stereotactic plane). The otoliths and mainly the vertical canals made contributions during stimulation around an earth-fixed horizontal axis (vertical stimulation). Head orientation was also slowly altered (2–3 deg/s) over a range of 180 deg under both stimulus conditions (tilted yaw and vertical stimulation). Neuronal data for each paradigm were fitted by a least squares best-sine function. Computation of the hypothetical contributions made by all three pairs of semicircular canals and the otoliths to these responses showed that 74% of the 46 neurons investigated received an otolith input; in most instances it was combined with a canal input. Neurons most often received input from the horizontal and vertical canals as well as the otoliths. Only a minority of neurons received a purely otolith (13%), vertical canal (13%), or horizontal canal (4%) input. Conventional criteria (head position-related activity, spatiotemporal convergence, STC) failed to detect an otolith contribution in several such instances. Thus, canal-otolith convergence is the general rule at this central stage of vestibular information processing in the Fastigial Nucleus. The large variety of response types allows these neurons to participate in multiple tasks of vestibulospinal movement control.

  • Fastigial Nucleus activity during different frequencies and orientations of vertical vestibular stimulation in the monkey.
    Journal of neurophysiology, 1999
    Co-Authors: C. Siebold, J. F. Kleine, L. Glonti, T. Tchelidze, Ulrich Büttner
    Abstract:

    Neurons in the rostral part of the Fastigial Nucleus (FN) respond to vestibular stimulation but are not related to eye movements. To understand the precise role of these vestibular-only neurons in ...

  • Rostral Fastigial Nucleus activity in the alert monkey during three-dimensional passive head movements.
    Journal of neurophysiology, 1997
    Co-Authors: C. Siebold, L. Glonti, Stefan Glasauer, Ulrich Büttner
    Abstract:

    Siebold, C., L. Glonti, S. Glasauer, and U. Buttner. Rostral Fastigial Nucleus activity in the alert monkey during three-dimensional passive head movements. J. Neurophysiol. 77: 1432–1446, 1997. Th...

C. Siebold - One of the best experts on this subject based on the ideXlab platform.

  • Multimodal signal integration in vestibular neurons of the primate Fastigial Nucleus.
    Annals of the New York Academy of Sciences, 2003
    Co-Authors: Ulrich Büttner, Stefan Glasauer, L. Glonti, Y. Guan, E. Kipiani, J. F. Kleine, C. Siebold, T. Tchelidze, Andreas Wilden
    Abstract:

    : The rostral Fastigial Nucleus contains vestibular neurons, which presumably are involved in spinal mechanisms (neck, gait, posture) and which are not modulated with individual eye movements. Single-unit recordings in the alert behaving monkey during natural stimulus conditions reveal that virtually all neurons demonstrate integration of several sensory inputs. This applies not only for canal-canal and canal-otolith interaction, but also for otolith-otolith interaction. There is also some evidence that most neurons receive not only an utriculus but also a sacculus input. Furthermore, most neurons also respond to large-field optokinetic stimulation, reflecting visual-vestibular interaction. Neurons are also affected by the head on trunk position, which would allow these neurons to operate in a body-centered rather than a head-centered reference frame. These complex, multisensory features could permit Fastigial Nucleus neurons to rather specifically affect spinal motor functions.

  • Canal-otolith interaction in the Fastigial Nucleus of the alert monkey.
    Experimental brain research, 2001
    Co-Authors: C. Siebold, Stefan Glasauer, L. Glonti, J. F. Kleine, T. Tchelidze, E. Anagnostou, Ulrich Büttner
    Abstract:

    To determine the contribution of the otoliths as well as the horizontal and vertical semicircular canals to the response of "vestibular only" neurons in the rostral Fastigial Nucleus of the alert monkey, we applied natural sinusoidal vestibular stimuli (0.6 Hz; ±15 deg) around different axes. During the experiment the monkey sat erect in a primate chair with the head immobile. Semicircular canal responses were investigated during tilted yaw stimulation around an earth vertical axis. The tilt angle was varied by 30 deg and included the optimal plane for horizontal canal stimulation (15 deg nose down from the stereotactic plane). The otoliths and mainly the vertical canals made contributions during stimulation around an earth-fixed horizontal axis (vertical stimulation). Head orientation was also slowly altered (2–3 deg/s) over a range of 180 deg under both stimulus conditions (tilted yaw and vertical stimulation). Neuronal data for each paradigm were fitted by a least squares best-sine function. Computation of the hypothetical contributions made by all three pairs of semicircular canals and the otoliths to these responses showed that 74% of the 46 neurons investigated received an otolith input; in most instances it was combined with a canal input. Neurons most often received input from the horizontal and vertical canals as well as the otoliths. Only a minority of neurons received a purely otolith (13%), vertical canal (13%), or horizontal canal (4%) input. Conventional criteria (head position-related activity, spatiotemporal convergence, STC) failed to detect an otolith contribution in several such instances. Thus, canal-otolith convergence is the general rule at this central stage of vestibular information processing in the Fastigial Nucleus. The large variety of response types allows these neurons to participate in multiple tasks of vestibulospinal movement control.

  • Fastigial Nucleus activity during different frequencies and orientations of vertical vestibular stimulation in the monkey.
    Journal of neurophysiology, 1999
    Co-Authors: C. Siebold, J. F. Kleine, L. Glonti, T. Tchelidze, Ulrich Büttner
    Abstract:

    Neurons in the rostral part of the Fastigial Nucleus (FN) respond to vestibular stimulation but are not related to eye movements. To understand the precise role of these vestibular-only neurons in ...

  • Rostral Fastigial Nucleus activity in the alert monkey during three-dimensional passive head movements.
    Journal of neurophysiology, 1997
    Co-Authors: C. Siebold, L. Glonti, Stefan Glasauer, Ulrich Büttner
    Abstract:

    Siebold, C., L. Glonti, S. Glasauer, and U. Buttner. Rostral Fastigial Nucleus activity in the alert monkey during three-dimensional passive head movements. J. Neurophysiol. 77: 1432–1446, 1997. Th...

Laurent Goffart - One of the best experts on this subject based on the ideXlab platform.

Luo Zhe-wen - One of the best experts on this subject based on the ideXlab platform.

  • Electrical Stimulating Cerebellar Fastigial Nucleus Protects Retina against Ischemia/reperfusion Injury in Rats
    Journal of Kunming Medical University, 2011
    Co-Authors: Luo Zhe-wen
    Abstract:

    Objective To investigate the protective effect and mechanism of electrical stimulating cerebellar Fastigial Nucleus on retina against ischemia/reperfusion injury in rats.Methods Rats were divided randomly into three groups:group1(ischemia-reperfusion),group2(electrical-stimulating-treated),and group3(sham-operated).Apoptosis of retinal ganglion cells was detected by TUNEL method,and expression of Bcl-2 and Bax were measured by immunohistochemical staining methods.Results Ischemia/reperfusion injury induced the apoptosis of retinal ganglion cells(P0.05),meanwhile,as ischemia prolonged,the expression of Bcl-2 became weaker,and the expression of Bax became stronger gradually(P0.05).Electrical stimulating cerebellar Fastigial Nucleus alleviated these changes in treated group(P0.05).Conclusions Electrical stimulating cerebellar Fastigial Nucleus can protect retina against ischemia/reperfusion-injury.The possible mechanism includes upregulating the protein expression of Bcl-2 and downregualting the protein expression of Bax.

Albert F. Fuchs - One of the best experts on this subject based on the ideXlab platform.

  • Participation of Caudal Fastigial Nucleus in Smooth Pursuit Eye Movements. II. Effects of Muscimol Inactivation
    Journal of neurophysiology, 1997
    Co-Authors: Farrel R. Robinson, A. Straube, Albert F. Fuchs
    Abstract:

    Robinson, Farrel, R., Andreas Straube, and Albert F. Fuchs. Participation of the caudal Fastigial Nucleus in smooth pursuit eye movements. II. Effects of muscimol inactivation. J. Neurophysiol. 78:...

  • Role of the caudal Fastigial Nucleus in saccade generation. II. Effects of muscimol inactivation
    Journal of neurophysiology, 1993
    Co-Authors: Farrel R. Robinson, A. Straube, Albert F. Fuchs
    Abstract:

    1. We studied the effect of temporarily inhibiting neurons in the caudal Fastigial Nucleus in two rhesus macaques trained to make saccades to jumping targets. We placed injections of the gamma-amin...

  • role of the caudal Fastigial Nucleus in saccade generation ii effects of muscimol inactivation
    Journal of Neurophysiology, 1993
    Co-Authors: Farrel R. Robinson, A. Straube, Albert F. Fuchs
    Abstract:

    1. We studied the effect of temporarily inhibiting neurons in the caudal Fastigial Nucleus in two rhesus macaques trained to make saccades to jumping targets. We placed injections of the gamma-aminobutyric acid (GABA) agonist muscimol unilaterally or bilaterally at sites in the caudal Fastigial Nucleus where we had recorded saccade-related neurons a few minutes earlier. 2. Unilateral injections (n = 9) made horizontal saccades to the injected side hypermetric and those to the other side hypometric (mean gain of 1.37 and 0.61, respectively, for 10 degrees target steps, and 1.26 and 0.81 for 20 degrees target steps; normal saccade gain was 0.96). Saccades to vertical targets showed a small but significant hypermetria and curved strongly toward the side of the injection. The trajectories and end points of all targeted saccades were more variable than normal. 3. After unilateral injections, centripetal saccades were slightly larger than centrifugal saccades (mean gains for ipsilateral saccades were 1.42 and 1.31, respectively, for 10 degrees target steps, and 1.37 and 1.15 for 20 degrees target steps). 4. Unilateral injections increased the average acceleration of ipsilateral saccades and decreased the acceleration of contralateral saccades. Injections decreased both the acceleration and deceleration of vertical saccades. 5. After dysmetric saccades, monkeys acquired the target with an abnormally high number of hypometric corrective saccades. Injection increased the average number of corrective saccades from 0.6 to 2.1 after 10 degrees horizontal target steps and from 0.8 to 2.1 after 20 degrees steps. The size of each successive corrective saccade in a series decreased, and the latency from the previous corrective saccade increased. 6. Bilateral injections (n = 2) of muscimol, in which we injected first into the left caudal Fastigial Nucleus and then, within 30 min, into the right, made all saccades hypermetric (mean gain for 10 degrees right, left, up, and down saccades was 1.18, 1.49, 1.43, and 1.10, respectively). Paradoxically, bilateral injection decreased both saccade acceleration and deceleration. Saccade trajectories and end points were more variable than normal. 7. To account for the effects of our injections, we propose that the activity of caudal Fastigial neurons on one side normally helps to decelerate ipsilateral saccades and helps to accelerate contralateral saccades by influencing the feedback loop of the saccade burst generator in the brain stem. Without caudal Fastigial activity the brain stem burst generator produces hypermetric, variable saccades. We therefore also propose that the influence of caudal Fastigial neurons on the burst generator makes saccades more consistent and accurate.(ABSTRACT TRUNCATED AT 400 WORDS)