Universidad de los Andes 2 articles published in JoVE Behavior Fear Incubation Using an Extended Fear-Conditioning Protocol for Rats César Acevedo-Triana1,6, Javier L. Rico2, Leonardo A. Ortega2, Melissa Andrea N. Cardenas3, Fernando P. Cardenas3, Manuel J. Rojas4, Juan Carlos Forigua-Vargas2, Julián Cifuentes2, Camilo Hurtado-Parrado2,5 1School of Psychology, Universidad Pedagógica y Tecnológica de Colombia, 2Animal Behavior Laboratory, Fundación Universitaria Konrad Lorenz, 3Department of Psychology, Universidad de Los Andes, 4School of Veterinary Medicine, Animal Health Department, Universidad Nacional de Colombia, 5Department of Psychology, Troy University, 6Department of Neurobiology, University of Alabama at Birmingham We describe an extended fear-conditioning protocol that produces overtraining and fear incubation in rats. This protocol entails a single training session with 25 tone-shock pairings (i.e., overtraining) and a comparison of conditioned freezing responses during context and cue tests 48 h (short-term) and 6 weeks (long-term) after training. Developmental Biology Establishment of Larval Zebrafish as an Animal Model to Investigate Trypanosoma cruzi Motility In Vivo Veronica Akle1, Nathalie Agudelo-Dueñas*1,2, Maria A. Molina-Rodriguez*1, Laurel Brianne Kartchner1,3,4,6, Annette Marie Ruth1,3,5,6, John M. González3, Manu Forero-Shelton2 1Laboratory of Neurosciences and Circadian Rhythms, School of Medicine, Universidad de los Andes, 2Biophysics Group, Department of Physics, Universidad de los Andes, 3Laboratory of Basic Medical Sciences, School of Medicine, Universidad de los Andes, 4Department of Microbiology and Immunology, University of North Carolina, 5Notre Dame Initiative for Global Development, University of Notre Dame, 6USAID Research and Innovation Fellowship program In this protocol, fluorescently labeled T. cruzi were injected into transparent zebrafish larvae, and parasite motility was observed in vivo using light sheet fluorescence microscopy.