Fig. 3.

Effects of muscimol-Elvax (A) and drug-free Elvax (B) implants on activity in ferret visual cortex. Recordings were made 2 h after implantation. Surface-normal electrode penetrations were made either directly beneath the Elvax (through a small hole that had been bored before implantation) or close to the lateral edge of the implant. Recordings were made every 50 μm and each sampling site is represented by a box: black boxes indicate that no activity was recorded, gray boxes indicate spontaneous activity, and white boxes mark positions where visual activity was recorded. Muscimol-Elvax largely eliminated activity throughout the depth of the cortex, whereas the drug-free control implants appeared to have no effect on the activity of the cortex.