Mice lacking the visual cycle enzymes RPE65 or lecithin-retinol acyl transferase (Lrat) have pupillary light responses (PLR) that are less sensitive than those of mice with outer retinal degeneration (rd/rd or rdta). Inner retinal photoresponses are mediated by melanopsin-expressing, intrinsically photosensitive retinal ganglion cells (ipRGCs), suggesting… (More)
PURPOSE Mice lacking rods and cones retain pupillary light reflexes that are mediated by intrinsically photosensitive retinal ganglion cells (ipRGCs). Melanopsin is necessary and sufficient for this nonvisual photoreception. The mammalian inner retina also expresses the potential blue light photopigments cryptochromes 1 and 2. Previous studies have shown… (More)
The effect of frequency modulation on acoustic middle ear muscle reflex persistence was studied. Changes in impedance at the tympanic membrane were used as an indirect indication of reflex activity. Signals were a 2-kHz pure tone, a narrow band of noise centered at 2-kHz, and FM signals centered at 2-kHz modulated 70, 140, and 280 times per second.