title: Effects of X-ray radiation on complex visual discrimination learning and social recognition memory in rats.
abstract: The present report describes an animal model for examining the effects of radiation on a range of neurocognitive functions in rodents that are similar to a number of basic human cognitive functions. Fourteen male Long-Evans rats were trained to perform an automated intra-dimensional set shifting task that consisted of their learning a basic discrimination between two stimulus shapes followed by more complex discrimination stages (e.g., a discrimination reversal, a compound discrimination, a compound reversal, a new shape discrimination, and an intra-dimensional stimulus discrimination reversal). One group of rats was exposed to head-only X-ray radiation (2.3 Gy at a dose rate of 1.9 Gy/min), while a second group received a sham-radiation exposure using the same anesthesia protocol. The irradiated group responded less, had elevated numbers of omitted trials, increased errors, and greater response latencies compared to the sham-irradiated control group. Additionally, social odor recognition memory was tested after radiation exposure by assessing the degree to which rats explored wooden beads impregnated with either their own odors or with the odors of novel, unfamiliar rats; however, no significant effects of radiation on social odor recognition memory were observed. These data suggest that rodent tasks assessing higher-level human cognitive domains are useful in examining the effects of radiation on the CNS, and may be applicable in approximating CNS risks from radiation exposure in clinical populations receiving whole brain irradiation.
authors.affiliation: Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Davis
authors.affiliation: Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America; Institutes for Behavior Resources, Baltimore, Maryland, United States of America.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Roma
authors.affiliation: Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America.
authors.forename: Elwood
authors.initials: E
authors.lastname: Armour
authors.affiliation: Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America.
authors.forename: Virginia L
authors.initials: VL
authors.lastname: Gooden
authors.affiliation: Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America; Institutes for Behavior Resources, Baltimore, Maryland, United States of America.
authors.forename: Joseph V
authors.initials: JV
authors.lastname: Brady
authors.affiliation: Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Weed
authors.affiliation: Division of Behavioral Biology, Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America; Institutes for Behavior Resources, Baltimore, Maryland, United States of America.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Hienz
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects*; D006801:Humans; D007858:Learning / Q000528:radiation effects*; D008297:Male; D008568:Memory / Q000528:radiation effects*; D051381:Rats; D020318:Rats, Long-Evans; D012919:Social Behavior; D014796:Visual Perception / Q000528:radiation effects*; D014965:X-Rays / Q000009:adverse effects*
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