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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) HWHH histogram of the left monocular, the right monocular, and the binocular responses for cortical cells in a 35 × 60 section inside the binocular region. There is a large chunk of cells which are poorly orientation tuned, but there is also a large number of cells with good orientation tuning. Tuning properties of monocular responses are better than binocular responses. (B) HWHH histogram for a 35 × 60 section of cells in the monocular region. (C) Scatter plot between HWHH and maximum spike rate (spikes/s) of binocular response for a 35 × 60 section of cells in the binocular region of the cortex.
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Figure 4: (A) HWHH histogram of the left monocular, the right monocular, and the binocular responses for cortical cells in a 35 × 60 section inside the binocular region. There is a large chunk of cells which are poorly orientation tuned, but there is also a large number of cells with good orientation tuning. Tuning properties of monocular responses are better than binocular responses. (B) HWHH histogram for a 35 × 60 section of cells in the monocular region. (C) Scatter plot between HWHH and maximum spike rate (spikes/s) of binocular response for a 35 × 60 section of cells in the binocular region of the cortex.

Mentions: Some studies (Metin et al., 1988; Niell and Stryker, 2008) report that the tuning width of mouse cells is very good, around 20° while others (Metin et al., 1988; Van Hooser, 2007) report that they could not get many highly tuned cells when inhibition was turned off. In our study we have feedforward excitatory connections from LGN to cortex. We get some cells that are highly tuned, while there is also a considerable number that have large HWHH and hence, are poorly tuned. Cells with three subregions shows better tuning as compared to cells with two subregions, particularly if one of the two subregion is bigger in size. Also cells with patchy subregions i.e., not well-formed subregions are poorly orientation selective. For cortical cells in binocular region, HWHH histogram for right monocular, left monocular, and binocular responses are shown in Figure 4A. A number of cells have low values of HWHH (≤20°) in their monocular response. However, only those cells that do not have large difference between the left and the right eye orientation preference have low values of HWHH in binocular response. HWHH histogram for cortical cells in monocular region is shown in Figure 4B. Note that the HWHH histogram for cells in monocular region is similar to the HWHH histogram for binocular response of cells in binocular region. This is because spike rates for monocular cells are similar to the spike rates for binocular response in binocular cells. Figure 4C depicts spike rate as function of HWHH for cells in binocular zone. We observe that for low spike rate, we are more likely to get better orientation tuning.


Development and matching of binocular orientation preference in mouse V1.

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

(A) HWHH histogram of the left monocular, the right monocular, and the binocular responses for cortical cells in a 35 × 60 section inside the binocular region. There is a large chunk of cells which are poorly orientation tuned, but there is also a large number of cells with good orientation tuning. Tuning properties of monocular responses are better than binocular responses. (B) HWHH histogram for a 35 × 60 section of cells in the monocular region. (C) Scatter plot between HWHH and maximum spike rate (spikes/s) of binocular response for a 35 × 60 section of cells in the binocular region of the cortex.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 4: (A) HWHH histogram of the left monocular, the right monocular, and the binocular responses for cortical cells in a 35 × 60 section inside the binocular region. There is a large chunk of cells which are poorly orientation tuned, but there is also a large number of cells with good orientation tuning. Tuning properties of monocular responses are better than binocular responses. (B) HWHH histogram for a 35 × 60 section of cells in the monocular region. (C) Scatter plot between HWHH and maximum spike rate (spikes/s) of binocular response for a 35 × 60 section of cells in the binocular region of the cortex.
Mentions: Some studies (Metin et al., 1988; Niell and Stryker, 2008) report that the tuning width of mouse cells is very good, around 20° while others (Metin et al., 1988; Van Hooser, 2007) report that they could not get many highly tuned cells when inhibition was turned off. In our study we have feedforward excitatory connections from LGN to cortex. We get some cells that are highly tuned, while there is also a considerable number that have large HWHH and hence, are poorly tuned. Cells with three subregions shows better tuning as compared to cells with two subregions, particularly if one of the two subregion is bigger in size. Also cells with patchy subregions i.e., not well-formed subregions are poorly orientation selective. For cortical cells in binocular region, HWHH histogram for right monocular, left monocular, and binocular responses are shown in Figure 4A. A number of cells have low values of HWHH (≤20°) in their monocular response. However, only those cells that do not have large difference between the left and the right eye orientation preference have low values of HWHH in binocular response. HWHH histogram for cortical cells in monocular region is shown in Figure 4B. Note that the HWHH histogram for cells in monocular region is similar to the HWHH histogram for binocular response of cells in binocular region. This is because spike rates for monocular cells are similar to the spike rates for binocular response in binocular cells. Figure 4C depicts spike rate as function of HWHH for cells in binocular zone. We observe that for low spike rate, we are more likely to get better orientation tuning.

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