Oral progesterone decreases saccadic eye velocity and increases sedation in women

We describe preliminary attempts to fit a mathematical function to the slow-component eye velocity (SCV) over the time course of caloric-induced nystagmus. Initially, we consider a Weibull equation with three parameters. These parameters are estimated by a least-squares procedure to fit digitized SCV data. We present examples of SCV data and fitted curves to show how adjustments in the parameters of the model affect the fitted curve. The best fitting parameters are presented for curves fit to 120 warm caloric responses. The fitting parameters and the efficacy of the fitted curves are compared before and after the SCV data were smoothed to reduce response variability. We also consider a more flexible four-parameter Weibull equation that, for 98% of the smoothed caloric responses, yields fits that describe the data more precisely than a line through the mean. Finally, we consider advantages and problems in fitting the Weibull function to caloric data.

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Existence in the nucleus incertus of the cat of horizontal-eye-movement-related neurons projecting to the cerebellar flocculus

Journal of Neurophysiology ◽

10.1152/jn.1995.74.3.1367 ◽

1995 ◽

Vol 74 (3) ◽

pp. 1367-1372 ◽

Cited By ~ 15

Author(s):

G. Cheron ◽

S. Saussez ◽

N. Gerrits ◽

E. Godaux

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Retrograde Transport ◽

Great Sensitivity ◽

Antidromic Activation ◽

Vertical Movements ◽

Cerebellar Flocculus ◽

Nucleus Incertus ◽

Alert Cats ◽

Eye Velocity

1. Properties of nucleus incertus (NIC) neurons projecting to the cerebellar flocculus were studied in alert cats by using chronic unit and eye movement recording and antidromic activation. Projection of these neurons onto the flocculus was verified with retrograde transport of horseradish peroxidase after injections in the flocculus. 2. Bipolar stimulation electrodes were implanted into the "middle" zone of each flocculus because this zone is known to be involved in the control of horizontal eye movements. The dorsomedial aspect of the pontine tegmentum was explored with microelectrodes during stimulation of both flocculi. The majority of neurons antidromically activated from the flocculus were found in the caudal part of the NIC. 3. Of the 69 neurons activated from the flocculus, 44 were classified as burst-tonic (BT) neurons; 34 discharged in relation with horizontal movements of the eye, 10 in relation with vertical movements. Of the 14 remaining neurons, 6 were not related to eye movements and 8 were classified as burst neurons. The BT neurons of the NIC displayed a great sensitivity to both horizontal eye position and horizontal eye velocity. 4. This study demonstrates the presence of a new group of horizontal eye movement related BT neurons situated in the NIC. The fact that they project to the horizontal floccular zone emphasizes the importance of the functional specialization of the different Purkinje cell zones.

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Role of Cerebellar Uvula-Nodulus in the Control of Head Orientation-Specific Eye Velocity in the Rabbit

Annals of the New York Academy of Sciences ◽

10.1111/j.1749-6632.1996.tb15738.x ◽

1996 ◽

Vol 781 (1 Lipids and Sy) ◽

pp. 614-618 ◽

Cited By ~ 7

Author(s):

P. ERRICO ◽

A. A. FERRARESI ◽

N. H. BARMACK ◽

V. E. PETTOROSSF

Keyword(s):

Head Orientation ◽

Eye Velocity

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Anatomy and Physiology of the Primate Interstitial Nucleus of Cajal. II. Discharge Pattern of Single Efferent Fibers

Journal of Neurophysiology ◽

10.1152/jn.1998.80.6.3100 ◽

1998 ◽

Vol 80 (6) ◽

pp. 3100-3111 ◽

Cited By ~ 15

Author(s):

Y. Dalezios ◽

C. A. Scudder ◽

S. M. Highstein ◽

A. K. Moschovakis

Keyword(s):

Smooth Pursuit ◽

Discharge Pattern ◽

Eye Position ◽

Interstitial Nucleus Of Cajal ◽

Anatomy And Physiology ◽

Saccade Size ◽

Saccade Velocity ◽

Behaving Monkeys ◽

Eye Velocity ◽

Vertical Up

Dalezios, Y., C. A. Scudder, S. M. Highstein, and A. K. Moschovakis. Anatomy and physiology of the primate interstitial nucleus of Cajal. II. Discharge pattern of single efferent fibers. J. Neurophysiol. 80: 3100–3111, 1998. Single efferent fibers of the interstitial nucleus of Cajal (NIC) were characterized physiologically and injected with biocytin in alert behaving monkeys. Quantitative analysis demonstrated that their discharge encodes a constellation of oculomotor variables. Tonic and phasic signals were related to vertical (up or down) eye position and saccades, respectively. Depending on how they encoded eye position, saccade velocity, saccade size, saccade duration, and smooth-pursuit eye velocity, fibers were characterized as regular or irregular, bi- or unidirectionally modulated, more or less sensitive, and reliable or unreliable. Further, fibers that did not burst for saccades (tonic) and fibers the eye-position and saccade-related signals of which increased in the same (in-phase) or in the opposite (anti-phase) directions were encountered. A continuum of discharge properties was the rule. We conclude that NIC efferent fibers send a combination of eye-position, saccade-, and smooth-pursuit-related signals, mixed in proportions that differ for different fibers, to targets of the vertical neural integrator such as extraocular motoneurons.

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