Journal: Progress in brain research

Article Title: Microstimulation of visual cortex to restore vision

doi: 10.1016/S0079-6123(09)17524-6

Figure Lengend Snippet: Retinal lesioning. All lesions were made using a NIDEK GYC-2000 532-nm photocoagulation laser. (A) Left: Picture of the right eye fundus immediately after inducing a laser photocoagulation lesion. The lesion appears white. Right: Picture of the right fundus after extraction and fixation in formaldehyde at the end of the experiment, 9 months later. The monkey had been euthanized and perfused with formaldehyde prior to extraction. Note the hyperpigmented scar (white arrow), which corresponds to the retinal lesion. (B) Fifteen-micrometer thick section through the center of the same lesion, stained with hematoxylin-eosin. Note that all retinal layers are essentially completely destroyed at the center of the lesion. (C) Saccade to visual target task used to map the visual-field scotoma induced in a macaque after a homonymous retinal lesion (D). Adjacent saccade targets were spaced by ~0.5°. Each dot represents a successful saccade to target. Note the absence of saccades outlining the area of the induced scotoma. Scale: Degrees. (D) Illustration of the lesions made in both fundi in order to induce a partly homonymous lesion. Left: Lesion in the left eye fundus. Right: Overlay of the right eye fundus (larger) and the left eye fundus (smaller square) illustrating the lesions (white patches marked by the black arrowheads). The left retina (small square overlay) was mirrored along the vertical axis and scaled to make the optical nerves overlap. Black dots outline the left eye lesion and its homonymous location in the right eye, which lies almost entirely over the right eye lesion resulting in an essentially homonymous left visual field scotoma. Note that lesions in each eye were offset from the fovea such that the foveal representation was spared, thereby allowing the animal to fixate accurately. Adapted from Smirnakis et al. (2005). (See Color Plate 23.8 in color plate section.)

Article Snippet: All lesions were made using a NIDEK GYC-2000 532-nm photocoagulation laser. (A) Left: Picture of the right eye fundus immediately after inducing a laser photocoagulation lesion.

Techniques: Extraction, Staining