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Processing of visual signals related to self-motion in the cerebellum of pigeons.

Wylie DR - Front Behav Neurosci (2013)

Bottom Line: Optic flow is the visual motion that occurs across the entire retina as a result of self-motion and is processed by subcortical visual pathways that project to the cerebellum.As the tectofugal system is involved in the analysis of local motion, there is integration of optic flow and local motion information in VI-VIII.This part of the cerebellum may be important for moving through a cluttered environment.

View Article: PubMed Central - PubMed

Affiliation: Centre for Neuroscience and Department of Psychology, University of Alberta Edmonton, AB, Canada.

ABSTRACT
In this paper I describe the key features of optic flow processing in pigeons. Optic flow is the visual motion that occurs across the entire retina as a result of self-motion and is processed by subcortical visual pathways that project to the cerebellum. These pathways originate in two retinal-recipient nuclei, the nucleus of the basal optic root (nBOR) and the nucleus lentiformis mesencephali, which project to the vestibulocerebellum (VbC) (folia IXcd and X), directly as mossy fibers, and indirectly as climbing fibers from the inferior olive. Optic flow information is integrated with vestibular input in the VbC. There is a clear separation of function in the VbC: Purkinje cells in the flocculus process optic flow resulting from self-rotation, whereas Purkinje cells in the uvula/nodulus process optic flow resulting from self-translation. Furthermore, Purkinje cells with particular optic flow preferences are organized topographically into parasagittal "zones." These zones are correlated with expression of the isoenzyme aldolase C, also known as zebrin II (ZII). ZII expression is heterogeneous such that there are parasagittal stripes of Purkinje cells that have high expression (ZII+) alternating with stripes of Purkinje cells with low expression (ZII-). A functional zone spans a ZII± stripe pair. That is, each zone that contains Purkinje cells responsive to a particular pattern of optic flow is subdivided into a strip containing ZII+ Purkinje cells and a strip containing ZII- Purkinje cells. Additionally, there is optic flow input to folia VI-VIII of the cerebellum from lentiformis mesencephali. These folia also receive visual input from the tectofugal system via pontine nuclei. As the tectofugal system is involved in the analysis of local motion, there is integration of optic flow and local motion information in VI-VIII. This part of the cerebellum may be important for moving through a cluttered environment.

No MeSH data available.


Related in: MedlinePlus

Basic visual processing in the accessory optic system in birds. (A) and (B), Respectively, show Nissl-stained coronal sections through the pigeon lentiformis mesenceophali (LM) and nucleus of the basal optic root (nBOR). (C) Indicates that most nBOR and LM neurons have large receptive fields in the contralateral visual field and exhibit directional tuning in response to largefield motion (e.g., Burns and Wallman, 1981; Winterson and Brauth, 1985). (D) Shows the response of a nBOR neuron to upward (excitation) and downward (inhibition) motion of a large drifting sine-wave grating (from Crowder and Wylie, 2001). (E) Shows a directional tuning curve of a typical nBOR neuron. Firing rate (spikes/s) is plotted as a function of the direction of motion in polar coordinates, and the gray circle represents the neuron's spontaneous firing rate. The directions are indicated as follows: U, upward; D, downward; F, forward or temporal-to-nasal (T-N), and B, backward or nasal-to-temporal (N-T). (F) Shows a distribution of the direction preferences of LM neurons in pigeons: most prefer forward motion (adapted from Wylie and Crowder, 2000). (G) Shows a distribution of the direction preferences of nBOR neurons in pigeons: most prefer upward, downward, or backward motion (Crowder et al., 2003).
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Figure 2: Basic visual processing in the accessory optic system in birds. (A) and (B), Respectively, show Nissl-stained coronal sections through the pigeon lentiformis mesenceophali (LM) and nucleus of the basal optic root (nBOR). (C) Indicates that most nBOR and LM neurons have large receptive fields in the contralateral visual field and exhibit directional tuning in response to largefield motion (e.g., Burns and Wallman, 1981; Winterson and Brauth, 1985). (D) Shows the response of a nBOR neuron to upward (excitation) and downward (inhibition) motion of a large drifting sine-wave grating (from Crowder and Wylie, 2001). (E) Shows a directional tuning curve of a typical nBOR neuron. Firing rate (spikes/s) is plotted as a function of the direction of motion in polar coordinates, and the gray circle represents the neuron's spontaneous firing rate. The directions are indicated as follows: U, upward; D, downward; F, forward or temporal-to-nasal (T-N), and B, backward or nasal-to-temporal (N-T). (F) Shows a distribution of the direction preferences of LM neurons in pigeons: most prefer forward motion (adapted from Wylie and Crowder, 2000). (G) Shows a distribution of the direction preferences of nBOR neurons in pigeons: most prefer upward, downward, or backward motion (Crowder et al., 2003).

Mentions: As self-motion causes visual motion across the entire retina, one would expect a system that analyzes this optic flow would respond to motion over large parts of the retina. Indeed, LM (Figure 2A) and nBOR (Figure 2B) neurons have large contralateral receptive fields (Figure 2C) averaging 60° in diameter with the largest encompassing the entire monocular visual field. These neurons are directionally selective in response to large stimuli, such as random dot patterns, checkerboards, and gratings (Figure 2D) (Burns and Wallman, 1981; Morgan and Frost, 1981; Gioanni et al., 1984). A tuning curve for a nBOR neuron is shown in Figure 2E (Wylie and Frost, 1990a). Although broadly tuned, the neuron shows a maximal response to upward motion (preferred direction) and is inhibited by downward motion (anti-preferred direction). Neurons in nBOR and LM show a complementary pattern of direction selectivity. In LM, most (>50%) neurons prefer forward (i.e., temporal-to-nasal) motion (Figure 2F) (Winterson and Brauth, 1985; Wylie and Frost, 1996; Wylie and Crowder, 2000). In contrast, neurons preferring upward, downward and backward (i.e., nasal-to-temporal) motion are about equally abundant in nBOR, but fewer (5–10%) prefer forward motion (Figure 2G) (Gioanni et al., 1984; Wylie and Frost, 1990a; Crowder et al., 2003).


Processing of visual signals related to self-motion in the cerebellum of pigeons.

Wylie DR - Front Behav Neurosci (2013)

Basic visual processing in the accessory optic system in birds. (A) and (B), Respectively, show Nissl-stained coronal sections through the pigeon lentiformis mesenceophali (LM) and nucleus of the basal optic root (nBOR). (C) Indicates that most nBOR and LM neurons have large receptive fields in the contralateral visual field and exhibit directional tuning in response to largefield motion (e.g., Burns and Wallman, 1981; Winterson and Brauth, 1985). (D) Shows the response of a nBOR neuron to upward (excitation) and downward (inhibition) motion of a large drifting sine-wave grating (from Crowder and Wylie, 2001). (E) Shows a directional tuning curve of a typical nBOR neuron. Firing rate (spikes/s) is plotted as a function of the direction of motion in polar coordinates, and the gray circle represents the neuron's spontaneous firing rate. The directions are indicated as follows: U, upward; D, downward; F, forward or temporal-to-nasal (T-N), and B, backward or nasal-to-temporal (N-T). (F) Shows a distribution of the direction preferences of LM neurons in pigeons: most prefer forward motion (adapted from Wylie and Crowder, 2000). (G) Shows a distribution of the direction preferences of nBOR neurons in pigeons: most prefer upward, downward, or backward motion (Crowder et al., 2003).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3569843&req=5

Figure 2: Basic visual processing in the accessory optic system in birds. (A) and (B), Respectively, show Nissl-stained coronal sections through the pigeon lentiformis mesenceophali (LM) and nucleus of the basal optic root (nBOR). (C) Indicates that most nBOR and LM neurons have large receptive fields in the contralateral visual field and exhibit directional tuning in response to largefield motion (e.g., Burns and Wallman, 1981; Winterson and Brauth, 1985). (D) Shows the response of a nBOR neuron to upward (excitation) and downward (inhibition) motion of a large drifting sine-wave grating (from Crowder and Wylie, 2001). (E) Shows a directional tuning curve of a typical nBOR neuron. Firing rate (spikes/s) is plotted as a function of the direction of motion in polar coordinates, and the gray circle represents the neuron's spontaneous firing rate. The directions are indicated as follows: U, upward; D, downward; F, forward or temporal-to-nasal (T-N), and B, backward or nasal-to-temporal (N-T). (F) Shows a distribution of the direction preferences of LM neurons in pigeons: most prefer forward motion (adapted from Wylie and Crowder, 2000). (G) Shows a distribution of the direction preferences of nBOR neurons in pigeons: most prefer upward, downward, or backward motion (Crowder et al., 2003).
Mentions: As self-motion causes visual motion across the entire retina, one would expect a system that analyzes this optic flow would respond to motion over large parts of the retina. Indeed, LM (Figure 2A) and nBOR (Figure 2B) neurons have large contralateral receptive fields (Figure 2C) averaging 60° in diameter with the largest encompassing the entire monocular visual field. These neurons are directionally selective in response to large stimuli, such as random dot patterns, checkerboards, and gratings (Figure 2D) (Burns and Wallman, 1981; Morgan and Frost, 1981; Gioanni et al., 1984). A tuning curve for a nBOR neuron is shown in Figure 2E (Wylie and Frost, 1990a). Although broadly tuned, the neuron shows a maximal response to upward motion (preferred direction) and is inhibited by downward motion (anti-preferred direction). Neurons in nBOR and LM show a complementary pattern of direction selectivity. In LM, most (>50%) neurons prefer forward (i.e., temporal-to-nasal) motion (Figure 2F) (Winterson and Brauth, 1985; Wylie and Frost, 1996; Wylie and Crowder, 2000). In contrast, neurons preferring upward, downward and backward (i.e., nasal-to-temporal) motion are about equally abundant in nBOR, but fewer (5–10%) prefer forward motion (Figure 2G) (Gioanni et al., 1984; Wylie and Frost, 1990a; Crowder et al., 2003).

Bottom Line: Optic flow is the visual motion that occurs across the entire retina as a result of self-motion and is processed by subcortical visual pathways that project to the cerebellum.As the tectofugal system is involved in the analysis of local motion, there is integration of optic flow and local motion information in VI-VIII.This part of the cerebellum may be important for moving through a cluttered environment.

View Article: PubMed Central - PubMed

Affiliation: Centre for Neuroscience and Department of Psychology, University of Alberta Edmonton, AB, Canada.

ABSTRACT
In this paper I describe the key features of optic flow processing in pigeons. Optic flow is the visual motion that occurs across the entire retina as a result of self-motion and is processed by subcortical visual pathways that project to the cerebellum. These pathways originate in two retinal-recipient nuclei, the nucleus of the basal optic root (nBOR) and the nucleus lentiformis mesencephali, which project to the vestibulocerebellum (VbC) (folia IXcd and X), directly as mossy fibers, and indirectly as climbing fibers from the inferior olive. Optic flow information is integrated with vestibular input in the VbC. There is a clear separation of function in the VbC: Purkinje cells in the flocculus process optic flow resulting from self-rotation, whereas Purkinje cells in the uvula/nodulus process optic flow resulting from self-translation. Furthermore, Purkinje cells with particular optic flow preferences are organized topographically into parasagittal "zones." These zones are correlated with expression of the isoenzyme aldolase C, also known as zebrin II (ZII). ZII expression is heterogeneous such that there are parasagittal stripes of Purkinje cells that have high expression (ZII+) alternating with stripes of Purkinje cells with low expression (ZII-). A functional zone spans a ZII± stripe pair. That is, each zone that contains Purkinje cells responsive to a particular pattern of optic flow is subdivided into a strip containing ZII+ Purkinje cells and a strip containing ZII- Purkinje cells. Additionally, there is optic flow input to folia VI-VIII of the cerebellum from lentiformis mesencephali. These folia also receive visual input from the tectofugal system via pontine nuclei. As the tectofugal system is involved in the analysis of local motion, there is integration of optic flow and local motion information in VI-VIII. This part of the cerebellum may be important for moving through a cluttered environment.

No MeSH data available.


Related in: MedlinePlus