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Development and matching of binocular orientation preference in mouse V1.

Bhaumik B, Shah NP - Front Syst Neurosci (2014)

Bottom Line: At the end of critical period 39% of cells in binocular zone in our model cortex is orientation selective.The starting and the closing time for critical period determine the orientation preference alignment between the two eyes and orientation tuning in cortical cells.It also results in much lower % of orientation selective cells in mice as compared to ferrets and cats having organized orientation maps with pinwheels.

View Article: PubMed Central - PubMed

Affiliation: Electrical Engineering Department, Indian Institute of Technology Delhi New Delhi, India.

ABSTRACT
Eye-specific thalamic inputs converge in the primary visual cortex (V1) and form the basis of binocular vision. For normal binocular perceptions, such as depth and stereopsis, binocularly matched orientation preference between the two eyes is required. A critical period of binocular matching of orientation preference in mice during normal development is reported in literature. Using a reaction diffusion model we present the development of RF and orientation selectivity in mouse V1 and investigate the binocular orientation preference matching during the critical period. At the onset of the critical period the preferred orientations of the modeled cells are mostly mismatched in the two eyes and the mismatch decreases and reaches levels reported in juvenile mouse by the end of the critical period. At the end of critical period 39% of cells in binocular zone in our model cortex is orientation selective. In literature around 40% cortical cells are reported as orientation selective in mouse V1. The starting and the closing time for critical period determine the orientation preference alignment between the two eyes and orientation tuning in cortical cells. The absence of near neighbor interaction among cortical cells during the development of thalamo-cortical wiring causes a salt and pepper organization in the orientation preference map in mice. It also results in much lower % of orientation selective cells in mice as compared to ferrets and cats having organized orientation maps with pinwheels.

No MeSH data available.


Related in: MedlinePlus

The three layered visual pathway model. We have modeled 40° of binocular and left monocular visual fields each as shown in (A). The left and the right eye retinae are 80 × 80 each. The left eye specific LGN layer is 80 × 80 with 40 × 80 region getting input from left monocular field and the rest 40 × 80 region from binocular field of vision. The right eye specific LGN layer is 40 × 80 and receives input from binocular field of vision. The cortical layer in the right hemisphere has left monocular and binocular regions of size 67 × 134 each. (B) The LGN layer for each eye has two sheets of cells each with center-surround structure—one for ON center and another for OFF center type cells. Each cortical cell in the left monocular region gets input from a 13 × 13 section of cells from the left eye specific LGN layer, whereas each cell in binocular region gets input from a 13 × 13 section of cells from both the left eye and the right eye specific LGN layers.
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Figure 1: The three layered visual pathway model. We have modeled 40° of binocular and left monocular visual fields each as shown in (A). The left and the right eye retinae are 80 × 80 each. The left eye specific LGN layer is 80 × 80 with 40 × 80 region getting input from left monocular field and the rest 40 × 80 region from binocular field of vision. The right eye specific LGN layer is 40 × 80 and receives input from binocular field of vision. The cortical layer in the right hemisphere has left monocular and binocular regions of size 67 × 134 each. (B) The LGN layer for each eye has two sheets of cells each with center-surround structure—one for ON center and another for OFF center type cells. Each cortical cell in the left monocular region gets input from a 13 × 13 section of cells from the left eye specific LGN layer, whereas each cell in binocular region gets input from a 13 × 13 section of cells from both the left eye and the right eye specific LGN layers.

Mentions: Mouse V1 has two zones: (i) the monocular zone, where neurons receive inputs only from the contralateral eye, and (ii) the binocular zone, where neurons receive inputs from both ipsi- and contralateral eyes as shown in Figure 1A. To obtain responses of cortical cells in our model mouse V1 we have used a three-layer visual pathway model as depicted in Figure 1B. In mouse the dendrites of retinal ganglion cells (RGCs) in the inner plexiform layer (IPL) of retina are separated into ON or OFF sublamina (Tian, 2004). We have modeled ON of OFF RGC as two separate layers. Retina for left (contralateral) eye is modeled with two 2D 80 × 80 sheet of ON and OFF center ganglion cells lying one over the other. The right (ipsilateral) retina is modeled with two 2D 40 × 80 layer of ON and OFF center ganglion cells. Mouse RGCs have center-surround receptive field structure with center fields having a radius of 5.5° and the surround field radius is 16.98° as reported in Grubb and Thompson (2003). Center-to-center spacing between the cells is 52′ of the visual angle. The ganglion cell model used earlier (Wehmeier et al., 1989; Wörgotter and Koch, 1991; Somers et al., 1995; Bhaumik and Mathur, 2003) for cats is modified to produce realistic temporal response to visual stimuli in mice. The details are given in the Supplementary Material.


Development and matching of binocular orientation preference in mouse V1.

Bhaumik B, Shah NP - Front Syst Neurosci (2014)

The three layered visual pathway model. We have modeled 40° of binocular and left monocular visual fields each as shown in (A). The left and the right eye retinae are 80 × 80 each. The left eye specific LGN layer is 80 × 80 with 40 × 80 region getting input from left monocular field and the rest 40 × 80 region from binocular field of vision. The right eye specific LGN layer is 40 × 80 and receives input from binocular field of vision. The cortical layer in the right hemisphere has left monocular and binocular regions of size 67 × 134 each. (B) The LGN layer for each eye has two sheets of cells each with center-surround structure—one for ON center and another for OFF center type cells. Each cortical cell in the left monocular region gets input from a 13 × 13 section of cells from the left eye specific LGN layer, whereas each cell in binocular region gets input from a 13 × 13 section of cells from both the left eye and the right eye specific LGN layers.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109519&req=5

Figure 1: The three layered visual pathway model. We have modeled 40° of binocular and left monocular visual fields each as shown in (A). The left and the right eye retinae are 80 × 80 each. The left eye specific LGN layer is 80 × 80 with 40 × 80 region getting input from left monocular field and the rest 40 × 80 region from binocular field of vision. The right eye specific LGN layer is 40 × 80 and receives input from binocular field of vision. The cortical layer in the right hemisphere has left monocular and binocular regions of size 67 × 134 each. (B) The LGN layer for each eye has two sheets of cells each with center-surround structure—one for ON center and another for OFF center type cells. Each cortical cell in the left monocular region gets input from a 13 × 13 section of cells from the left eye specific LGN layer, whereas each cell in binocular region gets input from a 13 × 13 section of cells from both the left eye and the right eye specific LGN layers.
Mentions: Mouse V1 has two zones: (i) the monocular zone, where neurons receive inputs only from the contralateral eye, and (ii) the binocular zone, where neurons receive inputs from both ipsi- and contralateral eyes as shown in Figure 1A. To obtain responses of cortical cells in our model mouse V1 we have used a three-layer visual pathway model as depicted in Figure 1B. In mouse the dendrites of retinal ganglion cells (RGCs) in the inner plexiform layer (IPL) of retina are separated into ON or OFF sublamina (Tian, 2004). We have modeled ON of OFF RGC as two separate layers. Retina for left (contralateral) eye is modeled with two 2D 80 × 80 sheet of ON and OFF center ganglion cells lying one over the other. The right (ipsilateral) retina is modeled with two 2D 40 × 80 layer of ON and OFF center ganglion cells. Mouse RGCs have center-surround receptive field structure with center fields having a radius of 5.5° and the surround field radius is 16.98° as reported in Grubb and Thompson (2003). Center-to-center spacing between the cells is 52′ of the visual angle. The ganglion cell model used earlier (Wehmeier et al., 1989; Wörgotter and Koch, 1991; Somers et al., 1995; Bhaumik and Mathur, 2003) for cats is modified to produce realistic temporal response to visual stimuli in mice. The details are given in the Supplementary Material.

Bottom Line: At the end of critical period 39% of cells in binocular zone in our model cortex is orientation selective.The starting and the closing time for critical period determine the orientation preference alignment between the two eyes and orientation tuning in cortical cells.It also results in much lower % of orientation selective cells in mice as compared to ferrets and cats having organized orientation maps with pinwheels.

View Article: PubMed Central - PubMed

Affiliation: Electrical Engineering Department, Indian Institute of Technology Delhi New Delhi, India.

ABSTRACT
Eye-specific thalamic inputs converge in the primary visual cortex (V1) and form the basis of binocular vision. For normal binocular perceptions, such as depth and stereopsis, binocularly matched orientation preference between the two eyes is required. A critical period of binocular matching of orientation preference in mice during normal development is reported in literature. Using a reaction diffusion model we present the development of RF and orientation selectivity in mouse V1 and investigate the binocular orientation preference matching during the critical period. At the onset of the critical period the preferred orientations of the modeled cells are mostly mismatched in the two eyes and the mismatch decreases and reaches levels reported in juvenile mouse by the end of the critical period. At the end of critical period 39% of cells in binocular zone in our model cortex is orientation selective. In literature around 40% cortical cells are reported as orientation selective in mouse V1. The starting and the closing time for critical period determine the orientation preference alignment between the two eyes and orientation tuning in cortical cells. The absence of near neighbor interaction among cortical cells during the development of thalamo-cortical wiring causes a salt and pepper organization in the orientation preference map in mice. It also results in much lower % of orientation selective cells in mice as compared to ferrets and cats having organized orientation maps with pinwheels.

No MeSH data available.


Related in: MedlinePlus