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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

(A,B) The left and the right RFs for a 5 × 5 section of cortex in the binocular zone are shown at 500 epochs, and 3000 epoch. RFs are locally diverse where near-by neurons have largely dissimilar receptive fields. The ON and OFF subregions are shown in Gray-scale with white (black) color representing connections from ON (OFF) LGN cells. The shading is proportional to strength of connection from LGN cells. At 500, epochs the sub-field structure is found only in few cells. The left and the right RFs are not similar as sub region correspondence factor is not included before 500th epoch. At 3000, the sub-field structure is visible. Due to sub region correspondence factor acting between 500 and 3000 epochs, the left and the right RFs become similar. Black boxes are marked around RFs for cells which are oriented in left and right eyes individually and the orientation preference difference between the left and the right eyes is less than 30°.
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Figure 3: (A,B) The left and the right RFs for a 5 × 5 section of cortex in the binocular zone are shown at 500 epochs, and 3000 epoch. RFs are locally diverse where near-by neurons have largely dissimilar receptive fields. The ON and OFF subregions are shown in Gray-scale with white (black) color representing connections from ON (OFF) LGN cells. The shading is proportional to strength of connection from LGN cells. At 500, epochs the sub-field structure is found only in few cells. The left and the right RFs are not similar as sub region correspondence factor is not included before 500th epoch. At 3000, the sub-field structure is visible. Due to sub region correspondence factor acting between 500 and 3000 epochs, the left and the right RFs become similar. Black boxes are marked around RFs for cells which are oriented in left and right eyes individually and the orientation preference difference between the left and the right eyes is less than 30°.

Mentions: Critical period is the period of heightened plasticity during which the orientation alignment between the left and the right eye receptive fields for cortical cells in the binocular zone takes place in normal development. Wang et al. (2010) reported that in mice, the left and the right eye receptive fields have poor matching of preferred orientation at the start of the critical period but they become matched by the end of it. Let t = Citer be the epoch at which the critical period starts and t = tc be the epoch for the end of critical period for orientation plasticity. In binocular zone therefore, we allow the left and the right eye receptive fields to develop independently till 500 epochs using Equation (1). From 500 to 3000 epochs we develop synaptic weights for binocular cells using Equation (2) wherein subregion correspondence factor is included in the reaction diffusion equation. The left and the right eye RFs at 500 and 3000 epochs for a 5 × 5 section of cortex in the binocular zone are shown in Figure 3. According to the feed-forward model proposed by Hubel and Wiesel (1962), orientation selectivity arises from specific arrangement of geniculate inputs. Ours is a feed forward model and the preferred orientation of modeled cortical cells is determined by the layout of the elongated ON and OFF subregions as shown in Figure 3B. RFs are locally highly diverse, with nearby neurons having largely dissimilar receptive fields. The ON and the OFF subregions are shown in Gray-scale with white (black) color representing strong synaptic connection from ON (OFF) LGN cells. The shading is proportional to the strength of the ON/OFF synaptic connections from the LGN cells. The choice of 500–3000 epochs as time window for critical period for orientation plasticity is justified later in this section.


Development and matching of binocular orientation preference in mouse V1.

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

(A,B) The left and the right RFs for a 5 × 5 section of cortex in the binocular zone are shown at 500 epochs, and 3000 epoch. RFs are locally diverse where near-by neurons have largely dissimilar receptive fields. The ON and OFF subregions are shown in Gray-scale with white (black) color representing connections from ON (OFF) LGN cells. The shading is proportional to strength of connection from LGN cells. At 500, epochs the sub-field structure is found only in few cells. The left and the right RFs are not similar as sub region correspondence factor is not included before 500th epoch. At 3000, the sub-field structure is visible. Due to sub region correspondence factor acting between 500 and 3000 epochs, the left and the right RFs become similar. Black boxes are marked around RFs for cells which are oriented in left and right eyes individually and the orientation preference difference between the left and the right eyes is less than 30°.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 3: (A,B) The left and the right RFs for a 5 × 5 section of cortex in the binocular zone are shown at 500 epochs, and 3000 epoch. RFs are locally diverse where near-by neurons have largely dissimilar receptive fields. The ON and OFF subregions are shown in Gray-scale with white (black) color representing connections from ON (OFF) LGN cells. The shading is proportional to strength of connection from LGN cells. At 500, epochs the sub-field structure is found only in few cells. The left and the right RFs are not similar as sub region correspondence factor is not included before 500th epoch. At 3000, the sub-field structure is visible. Due to sub region correspondence factor acting between 500 and 3000 epochs, the left and the right RFs become similar. Black boxes are marked around RFs for cells which are oriented in left and right eyes individually and the orientation preference difference between the left and the right eyes is less than 30°.
Mentions: Critical period is the period of heightened plasticity during which the orientation alignment between the left and the right eye receptive fields for cortical cells in the binocular zone takes place in normal development. Wang et al. (2010) reported that in mice, the left and the right eye receptive fields have poor matching of preferred orientation at the start of the critical period but they become matched by the end of it. Let t = Citer be the epoch at which the critical period starts and t = tc be the epoch for the end of critical period for orientation plasticity. In binocular zone therefore, we allow the left and the right eye receptive fields to develop independently till 500 epochs using Equation (1). From 500 to 3000 epochs we develop synaptic weights for binocular cells using Equation (2) wherein subregion correspondence factor is included in the reaction diffusion equation. The left and the right eye RFs at 500 and 3000 epochs for a 5 × 5 section of cortex in the binocular zone are shown in Figure 3. According to the feed-forward model proposed by Hubel and Wiesel (1962), orientation selectivity arises from specific arrangement of geniculate inputs. Ours is a feed forward model and the preferred orientation of modeled cortical cells is determined by the layout of the elongated ON and OFF subregions as shown in Figure 3B. RFs are locally highly diverse, with nearby neurons having largely dissimilar receptive fields. The ON and the OFF subregions are shown in Gray-scale with white (black) color representing strong synaptic connection from ON (OFF) LGN cells. The shading is proportional to the strength of the ON/OFF synaptic connections from the LGN cells. The choice of 500–3000 epochs as time window for critical period for orientation plasticity is justified later in this section.

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