Optokinetic nystagmus in the pigeon (Columba livia) II. Role of the pretectal nucleus of the accessory optic system (AOS)

1983 ◽  
Vol 50-50 (2-3) ◽  
Author(s):  
H. Gioanni ◽  
J. Rey ◽  
J. Villalobos ◽  
D. Richard ◽  
A. Dalbera
Keyword(s):  
Optokinetic Nystagmus ◽  
Columba Livia ◽  
Optic System ◽  
Accessory Optic System ◽  
Pretectal Nucleus

Optokinetic Nystagmus and the Accessory Optic System of Pigeon and Turtle

1979 ◽  
Vol 16 (3) ◽  
pp. 192-202 ◽  
Author(s):  
Katherine V. Fite ◽  
Anton Reiner ◽  
Stephen P. Hunt
Keyword(s):  
Optokinetic Nystagmus ◽  
Optic System ◽  
Accessory Optic System

Optokinetic nystagmus in cats with congenital strabismus

1996 ◽  
Vol 75 (4) ◽  
pp. 1495-1502 ◽  
Author(s):  
K. P. Hoffmann ◽  
C. Distler ◽  
C. Markner
Keyword(s):  
Visual Cortex ◽  
Eye Movements ◽  
Closed Loop ◽  
Optokinetic Nystagmus ◽  
Optic Tract ◽  
Open Loop ◽  
Differential Analysis ◽  
Accessory Optic System ◽  
Symmetry Index ◽  
Pretectal Nucleus

1. Eye movements were recorded in seven innately esotropic cats during monocular and binocular horizontal optokinetic stimulation, using the search coil technique in five cats and electrooculography in two cats. 2. During closed loop measurements in these strabismic cats, slow phases of optokinetic nystagmus (OKN) were characterized by an overall reduced gain when compared with normal controls. In addition, response gain to monocular nasotemporal stimulation was even more reduced than that to temporonasal stimulation, resulting in an increased asymmetry of closed loop gain. 3. During open loop measurements, eye velocity in strabismic cats was very low at all velocities tested. 4. Differential analysis of the symmetry of OKN revealed that all our strabismic cats had a "good" or more symmetric and a "poor" or more asymmetric eye. In addition, when analyzed separately at individual velocities, the symmetry index of the good eye was fairly constant over the velocity range tested. By contrast, the symmetry index of the poor eye dropped dramatically at higher stimulus velocities. 5. To analyze the relationship of OKN symmetry and cortical physiology, we calculated the ratio between the percentage of neurons driven by one eye in the ipsilateral and the contralateral cortical hemisphere. We found a weak correlation between OKN symmetry and this cortical symmetry index (P < 0.05, analysis of variance). 6. In conclusion, slow eye movements in cats with congenital esotropia are characterized by extremely low gain, especially at higher stimulus velocities. In addition, OKN symmetry during monocular stimulation is decreased. Our data suggest that OKN symmetry is weakly correlated with the proportion of binocular neurons in the visual cortex ipsilateral to the stimulated eye. However, OKN characteristics seem to reflect to a higher degree the response properties of neurons in the pretectal nucleus of the optic tract and the dorsal terminal nucleus of the accessory optic system than properties of neurons in the visual cortex.

Thalamic origin of neuropeptide Y innervation of the accessory optic nucleus of the pigeon (Columba livia)

1990 ◽  
Vol 5 (3) ◽  
pp. 249-259 ◽  
Author(s):  
Dânia E. Hamassaki ◽  
Luiz R. G. Britto
Keyword(s):  
Neuropeptide Y ◽  
Lateral Geniculate Nucleus ◽  
Functional Organization ◽  
Columba Livia ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Optic System ◽  
Accessory Optic System ◽  
Double Labeling ◽  
Lateral Geniculate ◽  
Electrolytic Lesions

AbstractImmunohistochemical and tracing techniques were used in combination to reveal the source of a neuropeptide Y-like immunoreactive (NPY-LI) plexus in the nucleus of the basal optic root (nBOR) of the pigeon accessory optic system. Injections of rhodamine-labeled latex microspheres into nBOR produced retrograde labeling of a population of neurons interposed between the principal optic nucleus of the dorsolateral thalamus (equivalent to the mammalian dorsal lateral geniculate nucleus) and the ventral lateral geniculate nucleus. The retrogradely labeled neurons were distributed mainly in the immediate vicinity of the lateral, dorsal, and ventral aspects of the nucleus rotundus. Immunohistochemical methods revealed many NPY-containing somata within the same intergeniculate thalamic area. Double-labeling immunohistochemical and retrograde tracing experiments evidenced that many NPY-LI neurons in the intergeniculate area contained rhodamine microspheres that had been previously injected into the ipsilateral nBOR. The projection of that general thalamic area to the nBOR was then confirmed by means of anterograde transport of Phaseolus vulgaris leucoagglutinin. In these experiments, the intergeniculate region was demonstrated to project to all divisions of the nBOR and to every other retino-recipient structure, including the suprachiasmatic nucleus. Finally, electrolytic lesions of the intergeniculate area produced a dramatic reduction in the number of NPY-LI axons and terminals within the ipsilateral nBOR and also within other retino-recipient structures. These data indicate the existence of a thalamic NPY-LI projection to the pigeon nBOR of the accessory optic system. This chemically specific projection originates from the intergeniculate area, which was shown in this study to project to all other retino-recipient structures. Thus, NPY may have a role in the functional organization of the accessory optic system and also of the avian visual system as a whole.

The interstitial nucleus of the superior fasciculus, posterior bundle (INSFp) in the guinea pig: Another nucleus of the accessory optic system processing the vertical retinal slip signal

1989 ◽  
Vol 2 (4) ◽  
pp. 377-382 ◽  
Author(s):  
C. Benassi ◽  
G. P. Biral ◽  
F. Lui ◽  
C. A. Porro ◽  
R. Corazza
Keyword(s):  
Guinea Pig ◽  
Optokinetic Nystagmus ◽  
Vertical Direction ◽  
Luminous Flux ◽  
Visual Signals ◽  
Optic System ◽  
Accessory Optic System ◽  
Retinal Slip ◽  
Visual Patterns ◽  
Medial Terminal Nucleus

AbstractAs in rabbit, gerbil, and rat, the guinea pig interstitial nucleus of the superior fasciculus, posterior bundle (INSFp) is a sparse assemblage of neurons scattered among the fibers forming the fasciculus bearing this name. Most of the INSFp neurons are small and are ovoid in shape. Interspersed among these, are a few larger, elongated neurons whose density becomes greater and whose shape becomes fusiform in correspondence to the zone of transition from the superior fasciculus to the ventral part of the medial terminal nucleus (MTN). Like the MTN, the INSFp is activated by retinal-slip signals evoked by whole-field visual patterns moving in the vertical direction, as shown by the increase of 14C-2-deoxyglucose (2DG) uptake into this nucleus. At the same level of luminous flux, neither pattern moving in the horizontal direction nor the same pattern held stationary can elicit increases in the INSFp 2DG assumption. The specificity of the observed increases in metabolic rates in INSFp following vertical whole-field motion suggests that this assemblage of neurons relays visual signals used in the control of vertical optokinetic nystagmus.

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