RESEARCH ARTICLE Rat tickling: A systematic review of applications, outcomes, and moderators Megan R. LaFollette1*, Marguerite E. O'Haire2, Sylvie Cloutier3, Whitney B. Blankenberger4, Brianna N. Gaskill1 1 Department of Animal Sciences, Center for Animal Welfare Science, College of Agriculture, Purdue University, West Lafayette, Indiana, United States of America, 2 Department of Comparative Pathobiology, Center for the Human-Animal Bond, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America, 3 Canadian Council on Animal Care, Assessment and Accreditation Section, Ottawa, ON, Canada, 4 Department of Comparative Medicine, Stanford University, Stanford, California, United States of America *
[email protected] a1111111111 a1111111111 Abstract a1111111111 a1111111111 a1111111111 Introduction Rats initially fear humans which can increase stress and impact study results. Additionally, studying positive affective states in rats has proved challenging. Rat tickling is a promising habituation technique that can also be used to model and measure positive affect. However, OPEN ACCESS current studies use a variety of methods to achieve differential results. Our objective was to Citation: LaFollette MR, O'Haire ME, Cloutier S, systematically identify, summarize, and evaluate the research on tickling in rats to provide Blankenberger WB, Gaskill BN (2017) Rat tickling: A systematic review of applications, outcomes, and direction for future investigation. Our specific aims were to summarize current methods moderators. PLoS ONE 12(4): e0175320. https:// used in tickling experiments, outcomes from tickling, and moderating factors. doi.org/10.1371/journal.pone.0175320 Editor: Sergio Pellis, University of Lethbridge, CANADA Methods Received: January 6, 2017 We systematically evaluated all articles about tickling identified from PubMed, Scopus, Web of Science, and PsychInfo.