Transmission of the visual signal to the brain depends on the proper organization of differentiated retinal cells into distinct nuclear and synaptic layers. Photoreceptors, which capture light photons, are located in the outer nuclear layer (ONL) closest to the retinal pigmented epithelium (RPE). These cells transmit a neural signal via the outer plexiform layer to the inner nuclear layer (INL) where the input signal is further processed by four classes of neuronal cells (amacrine, bipolar, horizontal and interplexiform).Texans defensive end Tim Jamison, Watt's backup, hurt his right Achilles tendon on the Packers' second scoring drive and the team said he wouldn't return. Jamison had a sack and a tipped pass in the first five games. Right guard Antoine Caldwell sustained a concussion and the team said he was out for the rest of the game..

Those two groups will be drawn from an initial larger study group of 1,000 current and former players from across the United States. Th