Fear and Assessment of Safety in Rats Selectively Bred for Differential Emission of 50 kHz Ultrasonic Vocalizations
Year: 2009
Type: article
Abstract: The goal of this study was to explore fear in rats that were selectively bred for variations in 50 kHz ultrasonic vocalizations (USVs) emission.Animals' USVs are related to affective states and have been shown to be vital for communication and social interactions.50 kHz USV emission during a tickle paradigm was used as the selection criterion for choosing breeders.Three animal lines were bred: high, low and random.The high line animals emit significantly more 50 kHz USVs when compared to the random line animals while the low line animals emit significantly fewer 50 kHz USVs than the random line animals.Random line animals were produced by arbitrarily choosing 2 breeders from two different litters.Prior studies have suggested a variation of affective states in these animals.Behavioral strategies were used as measures of whether or not the animals diverge on traits related to fear and the assessment of safety: 1) social recognition, 2) play suppression, and 3) prepulse inhibition (PPI).The social recognition task requires basic discrimination abilities and examined the ability of these animals to assess safety and familiarity in social situations.The play behavior paradigm investigated instinctual fear responses, conditioning and extinction of play suppression by observing play behavior for several days after exposure to the aversive unconditioned stimulus.The PPI test was used to assess reflexive fear and sensorimotor gating by measuring the acoustic startle response and the inhibition of this response.Results showed that low line animals had impaired social recognition abilities compared to random and high line animals.During play high line animals demonstrated exaggerated conditioned fear to the play apparatus.Conversely, low line animals failed to show contextual fear conditioning.I also would like to thank my committee members Verner Bingman and Laura Dilley for their service on this committee and advice given throughout this process.In addition, I thank Jaak Panksepp for agreeing to be a special guest at my thesis proposal meeting; his insight has guided the interpretation and analysis of my results.I also acknowledge and thank Jeff Burgdorf, for helping me learn the scoring process of USVs on spectrograms.Another individual who has helped me grasp the prior research on this topic is graduate student, Kelley Harmon.Thank you for all your help in the interpretation of both the prior research and the project at hand.Your advice has been invaluable to me.I also thank Travis Beckwith and Samantha Peña for all their help in running the experiments, you did an exemplary job.
Author: Emily S. Webber
Institution: Bowling Green State University
Language: English
Topic: Memory and Neural Mechanisms
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2267665093