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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

Mossy fiber projections from the nucleus of the basal optic root (nBOR) and lentiformis mesencephali (LM) to the zebrin (ZII) stripes in folium IXcd. (A) and (B) Show injections of green and red biotinylated dextran amine in nBOR and LM, respectively. (C) Shows a coronal section through IXcd reacted for ZII. The green terminal labeling from the nBOR is clustered adjacent to the ZII immunopositive (ZII+ve) stripes. (D) Shows a reconstruction of folium IXcd from serial sections. Each green and red dot represents a labeled terminal rosette from the injections in nBOR and LM, respectively, and the ZII+ve stripes are indicated in black. Note that most of the labeling is adjacent to the ZII+ve stripes. From Pakan et al. (2010). ?: Small immunopositive satellite band one to two Purkinje cells wide in the middle of P1−; Scale bars: (A,B) = 200 μm; (C) = 100 μm.
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Figure 10: Mossy fiber projections from the nucleus of the basal optic root (nBOR) and lentiformis mesencephali (LM) to the zebrin (ZII) stripes in folium IXcd. (A) and (B) Show injections of green and red biotinylated dextran amine in nBOR and LM, respectively. (C) Shows a coronal section through IXcd reacted for ZII. The green terminal labeling from the nBOR is clustered adjacent to the ZII immunopositive (ZII+ve) stripes. (D) Shows a reconstruction of folium IXcd from serial sections. Each green and red dot represents a labeled terminal rosette from the injections in nBOR and LM, respectively, and the ZII+ve stripes are indicated in black. Note that most of the labeling is adjacent to the ZII+ve stripes. From Pakan et al. (2010). ?: Small immunopositive satellite band one to two Purkinje cells wide in the middle of P1−; Scale bars: (A,B) = 200 μm; (C) = 100 μm.

Mentions: Although we have shown that each optic flow zone can be subdivided into a strip containing ZII+ve Purkinje cells and a strip containing ZII−ve Purkinje cells, the functional consequence of this remains unknown, as the function of ZII is not known. However, there are a few clues. First, shown in Figure 10, Pakan et al. (2010) found that most of the mossy fiber inputs from LM and nBOR (the green pathway shown in Figure 1) project adjacent to the ZII+ve stripes in IXcd. Thus, although both ZII+ve and ZII−ve neurons within a given optic flow zone receive visual input via climbing fibers from the mcIO, the ZII+ve cells seem to be getting more visual input via the mossy fiber pathways. Whether there are vestibular or somatomotor mossy afferents that project preferentially to ZII−ve stripes remains to be seen, but one could speculate that the ZII+ve and ZII−ve cells are processing different sensory information. Second, it has been shown that Purkinje cells in the ZII+ve and ZI−ve stripes within an optic flow zone likely project to different areas in the vestibular and cerebellar nuclei (Sugihara, 2011; Wylie et al., 2012). Finally, some studies have suggested that ZII+ve and ZII−ve cells may have different roles in plasticity (Nagao et al., 1997; Wadiche and Jahr, 2005; Ebner et al., 2012). For example, Paukert et al. (2010) showed that climbing fibers contacting ZII+ve Purkinje cells release more glutamate per action potential than those contacting ZII−ve Purkinje cells. They proposed that the ZII+ve Purkinje cells undergo more activity-dependent synaptic plasticity as a result. Thus, within an optic flow zone, there could be one system originating in ZII+ve stripes running in parallel with another system originating in ZII−ve stripes that differ with respect to: (1) mossy fiber inputs, (2) outputs to the vestibular and cerebellar nuclei, and (3) plasticity.


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

Wylie DR - Front Behav Neurosci (2013)

Mossy fiber projections from the nucleus of the basal optic root (nBOR) and lentiformis mesencephali (LM) to the zebrin (ZII) stripes in folium IXcd. (A) and (B) Show injections of green and red biotinylated dextran amine in nBOR and LM, respectively. (C) Shows a coronal section through IXcd reacted for ZII. The green terminal labeling from the nBOR is clustered adjacent to the ZII immunopositive (ZII+ve) stripes. (D) Shows a reconstruction of folium IXcd from serial sections. Each green and red dot represents a labeled terminal rosette from the injections in nBOR and LM, respectively, and the ZII+ve stripes are indicated in black. Note that most of the labeling is adjacent to the ZII+ve stripes. From Pakan et al. (2010). ?: Small immunopositive satellite band one to two Purkinje cells wide in the middle of P1−; Scale bars: (A,B) = 200 μm; (C) = 100 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 10: Mossy fiber projections from the nucleus of the basal optic root (nBOR) and lentiformis mesencephali (LM) to the zebrin (ZII) stripes in folium IXcd. (A) and (B) Show injections of green and red biotinylated dextran amine in nBOR and LM, respectively. (C) Shows a coronal section through IXcd reacted for ZII. The green terminal labeling from the nBOR is clustered adjacent to the ZII immunopositive (ZII+ve) stripes. (D) Shows a reconstruction of folium IXcd from serial sections. Each green and red dot represents a labeled terminal rosette from the injections in nBOR and LM, respectively, and the ZII+ve stripes are indicated in black. Note that most of the labeling is adjacent to the ZII+ve stripes. From Pakan et al. (2010). ?: Small immunopositive satellite band one to two Purkinje cells wide in the middle of P1−; Scale bars: (A,B) = 200 μm; (C) = 100 μm.
Mentions: Although we have shown that each optic flow zone can be subdivided into a strip containing ZII+ve Purkinje cells and a strip containing ZII−ve Purkinje cells, the functional consequence of this remains unknown, as the function of ZII is not known. However, there are a few clues. First, shown in Figure 10, Pakan et al. (2010) found that most of the mossy fiber inputs from LM and nBOR (the green pathway shown in Figure 1) project adjacent to the ZII+ve stripes in IXcd. Thus, although both ZII+ve and ZII−ve neurons within a given optic flow zone receive visual input via climbing fibers from the mcIO, the ZII+ve cells seem to be getting more visual input via the mossy fiber pathways. Whether there are vestibular or somatomotor mossy afferents that project preferentially to ZII−ve stripes remains to be seen, but one could speculate that the ZII+ve and ZII−ve cells are processing different sensory information. Second, it has been shown that Purkinje cells in the ZII+ve and ZI−ve stripes within an optic flow zone likely project to different areas in the vestibular and cerebellar nuclei (Sugihara, 2011; Wylie et al., 2012). Finally, some studies have suggested that ZII+ve and ZII−ve cells may have different roles in plasticity (Nagao et al., 1997; Wadiche and Jahr, 2005; Ebner et al., 2012). For example, Paukert et al. (2010) showed that climbing fibers contacting ZII+ve Purkinje cells release more glutamate per action potential than those contacting ZII−ve Purkinje cells. They proposed that the ZII+ve Purkinje cells undergo more activity-dependent synaptic plasticity as a result. Thus, within an optic flow zone, there could be one system originating in ZII+ve stripes running in parallel with another system originating in ZII−ve stripes that differ with respect to: (1) mossy fiber inputs, (2) outputs to the vestibular and cerebellar nuclei, and (3) plasticity.

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