Triggering different brain states using asynchronous serial communication to the rat amygdala

• Autor(a) principal: Flávio Afonso Gonçalves Mourão
• Data de Publicação: 2016
• Outros Autores: André Luiz Vieira Lockmann, Gabriel Perfeito Castro, Daniel de Castro Medeiros, Marina Pádua Reis, Grace Schenatto Pereira Moraes, André Ricardo Massensini, Marcio Flávio Dutra Moraes
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UFMG
• Texto Completo: https://doi.org/10.1093/cercor/bhu313; http://hdl.handle.net/1843/56295; https://orcid.org/0000-0002-4519-3585; https://orcid.org/0000-0002-1456-4689; https://orcid.org/0000-0003-0243-1309; https://orcid.org/0000-0002-2170-6649; https://orcid.org/0000-0002-1508-3801
• topic: Amygdaloid complex; Electrical microstimulation; Fear-conditioning; Prefrontal cortex; Temporal coding; Amigdalas; Medo

Inputting information to the brain through direct electrical microstimulation must consider how underlying neural networks encode information. One unexplored possibility is that a single electrode delivering temporally coded stimuli, mimicking an asynchronous serial communication port to the brain, can trigger the emergence of different brain states. This work used a discriminative fear-conditioning paradigm in rodents in which 2 temporally coded microstimulation patterns were targeted at the amygdaloid complex. Each stimulus was a binary-coded “word” made up of 10 ms bins, with 1's representing a single pulse stimulus: A-1001111001 and B-1110000111. During 3 consecutive retention tests (i.e., day-word: 1-B; 2-A, and 3-B), only binary-coded words previously paired with a foot-electroshock elicited proper aversive behavior. To determine the neural substrates recruited by the different stimulation patterns, c-Fos expression was evaluated 90 min after the last retention test. Animals conditioned to word-B, after stimulation with word-B, demonstrated increased hypothalamic c-Fos staining. Animals conditioned to word-A, however, showed increased prefrontal c-Fos labeling. In addition, prefrontal-cortex and hypothalamic c-Fos staining for, respectively, word-B- and word-A-conditioned animals, was not different than that of an unpaired control group. Our results suggest that, depending on the valence acquired from previous learning, temporally coded microstimulation activates distinct neural networks and associated behavior.