title: Selective, unilateral, reversible loss of behavioral responses to looming stimuli after injection of tetrodotoxin of cadmium chloride into the frog optic nerve.
abstract: Unilateral injection of tetrodotoxin or cadmium chloride into the frog optic nerve selectively eliminates behavioral responses to looming stimuli while sparing responses to prey stimuli. This behavioral loss is correlated with a loss of activity of "dimming" units in tectal layer G. These findings suggest that separate sets of retinal ganglion cell fibers carry information concerning looming stimuli and prey stimuli. The lack of activity in layer G suggests that information about looming stimuli is being conveyed by myelinated retinal ganglion cell axons. It is argued that unmyelinated fibers are not blocked by the neurotoxins because the extracellular space around the fibers is mostly inaccessible.
authors.affiliation: Biology Department, Temple University, Philadelphia, PA 19122, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: King
authors.forename: J Y
authors.initials: JY
authors.lastname: Lettvin
authors.forename: E D
authors.initials: ED
authors.lastname: Gruberg
mesh_terms: D000818:Animals; D019256:Cadmium Chloride / Q000008:administration & dosage / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D009900:Optic Nerve / Q000187:drug effects / Q000502:physiology*; D010775:Photic Stimulation; D011235:Predatory Behavior / Q000187:drug effects / Q000502:physiology*; D011894:Rana pipiens; D012165:Retinal Ganglion Cells / Q000502:physiology; D013477:Superior Colliculi / Q000187:drug effects / Q000502:physiology*; D013779:Tetrodotoxin / Q000008:administration & dosage / Q000494:pharmacology*; D014795:Visual Pathways / Q000187:drug effects / Q000502:physiology
chemical_list: D013779:Tetrodotoxin; D019256:Cadmium Chloride