Alterations in response properties in the lateral and dorsal terminal nuclei of the cat accessory optic system following visual cortex lesions

1984 ◽  
Vol 55 (1) ◽  
Author(s):  
K.L. Grasse ◽  
M.S. Cynader ◽  
R.M. Douglas
Keyword(s):  
Visual Cortex ◽  
Optic System ◽  
Accessory Optic System ◽  
Response Properties

The accessory optic system of rabbit. I. Basic visual response properties

1988 ◽  
Vol 60 (6) ◽  
pp. 2037-2054 ◽  
Author(s):  
R. E. Soodak ◽  
J. I. Simpson
Keyword(s):  
Ganglion Cells ◽  
Receptive Fields ◽  
Extracellular Recording ◽  
Vestibular Stimulation ◽  
Visual Response ◽  
Optic System ◽  
Accessory Optic System ◽  
Response Properties ◽  
Tuning Curves ◽  
Sinusoidal Oscillations

1. The response properties of accessory optic system (AOS) neurons were assessed using single-unit extracellular recording from each of the three AOS terminal nuclei [medial, lateral, and dorsal terminal nuclei (MTN, LTN, and DTN)] in the anesthetized rabbit. 2. AOS neurons had large, monocular (contralateral) receptive fields (tens of degrees on a side) and exhibited a pronounced selectivity to the speed and direction of movement of large, textured patterns. The greatest responses occurred at slow speeds on the order of 0.5 degrees/s. 3. MTN and LTN neurons responded best to movement in near vertical directions. However, the stimulus directions corresponding to the greatest excitation and the greatest inhibition both had a posterior component and, thus, the preferred excitatory and inhibitory directions were not opposite each other. DTN neurons responded most strongly to horizontal movement and were excited by temporal to nasal movement. 4. AOS neurons were unresponsive to natural vestibular stimulation presented as sinusoidal oscillations of the rabbit about the yaw, pitch, and roll axes. 5. The response properties of AOS neurons are remarkably similar to those of the ON, direction-selective ganglion cells of the rabbit retina, and therefore this class of ganglion cell is most likely the predominant, if not the only, direct retinal input to the AOS. The local direction-selective properties of AOS neurons can be accounted for by combining the tuning curves of ON, direction-selective ganglion cells in a simple manner. 6. The low speed preference of AOS neurons, along with their large receptive fields suggests that they are suited to complement the vestibular system in detecting self-motion.

Response Properties of Optic Flow Neurons in the Accessory Optic System of Hummingbirds vs. Zebra Finches and Pigeons

2021 ◽  
Author(s):  
Andrea H Gaede ◽  
Vikram B Baliga ◽  
Graham Smyth ◽  
Cristian Gutiérrez-Ibáñez ◽  
Douglas Leonard Altshuler ◽  
...  
Keyword(s):  
Optic Flow ◽  
Receptive Fields ◽  
Bird Species ◽  
Visual Response ◽  
Zebra Finches ◽  
Optic System ◽  
Accessory Optic System ◽  
Stimulus Velocity ◽  
Response Properties ◽  
Optokinetic Responses

Optokinetic responses function to maintain retinal image stabilization by minimizing optic flow that occurs during self-motion. The hovering ability of hummingbirds is an extreme example of this behaviour. Optokinetic responses are mediated by direction-selective neurons with large receptive fields in the accessory optic system (AOS) and pretectum. Recent studies in hummingbirds showed that, compared to other bird species, (i) the pretectal nucleus lentiformis mesencephali (LM) is hypertrophied, (ii) LM has a unique distribution of direction preferences, and (iii) LM neurons are more tightly tuned to stimulus velocity. In this study, we sought to determine if there are concomitant changes in the nucleus of the basal optic root (nBOR) of the AOS. We recorded the visual response properties of nBOR neurons to largefield drifting random dot patterns and sine wave gratings in Anna's hummingbirds and zebra finches and compared these with archival data from pigeons. We found no differences with respect to the distribution of direction preferences: Neurons responsive to upwards, downwards and nasal-to-temporal motion were equally represented in all three species, and neurons responsive to temporal-to-nasal motion were rare or absent (<5%). Compared to zebra finches and pigeons, however, hummingbird nBOR neurons were more tightly tuned to stimulus velocity of random dot stimuli. Moreover, in response to drifting gratings, hummingbird nBOR neurons are more tightly tuned in the spatio-temporal domain. These results, in combination with specialization in LM, supports a hypothesis that hummingbirds have evolved to be "optic flow specialist" to cope with the optomotor demands of sustained hovering flight.

Pharmacological isolation of visual cortical input to the cat accessory optic system: Effects of intravitreal tetrodotoxin on DTN unit responses

1991 ◽  
Vol 6 (2) ◽  
pp. 175-183 ◽  
Author(s):  
Keith L. Grasse
Keyword(s):  
Visual Cortex ◽  
Neural Mechanisms ◽  
Inhibitory Influence ◽  
Optic System ◽  
Accessory Optic System ◽  
Cortical Input ◽  
Before And After ◽  
Contralateral Eye ◽  
Visual Cortical ◽  
Stimulation Of

AbstractDirection-selective responses were recorded from neurons in the dorsal terminal nucleus (DTN) of the cat accessory optic system before and after intravitreal injections of tetrodotoxin (TTX) into the contralateral eye. After approximately 100 min, direction-selective responses driven through stimulation of the contralateral, injected eye were reduced on average by 90%, while direction-selective responses driven through stimulation of the ipsilateral, uninjected eye were not significantly reduced. By 200 min postinjection, ipsilateral direction-selective responses were either equal to or sometimes greater than control values. In the final stages of these experiments (i.e. between 390–830 min after contralateral eye injections), ipsilateral eye responses were on average 30% higher than control. The effects of retinal blockade of the contralateral eye by TTX show that input from the ipsilateral eye alone is sufficient to mediate direction-selective responses in DTN cells. These results and those observed following bicuculline eye injections reported previously (Grasse et al. 1990) demonstrate that direction-selective responses in the DTN driven through stimulation of the contralateral and ipsilateral eyes arise from independent neural mechanisms located in the retina and visual cortex, respectively. Moreover, these findings also suggest that the contralateral eye exerts an inhibitory influence over ipsilateral eye responses which is diminished by TTX injections into the contralateral eye.

Connectivity of the turtle accessory optic system

2003 ◽  
Vol 989 (1) ◽  
pp. 76-90 ◽  
Author(s):  
Amy E Weber ◽  
John Martin ◽  
Michael Ariel
Keyword(s):  
Optic System ◽  
Accessory Optic System
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