title: Triggering Different Brain States Using Asynchronous Serial Communication to the Rat Amygdala.
abstract: 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.
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Flávio Afonso Gonçalves
authors.initials: FAG
authors.lastname: Mourão
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: André Luiz Vieira
authors.initials: ALV
authors.lastname: Lockmann
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Gabriel Perfeito
authors.initials: GP
authors.lastname: Castro
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: de Castro Medeiros
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Marina Pádua
authors.initials: MP
authors.lastname: Reis
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Grace Schenatto
authors.initials: GS
authors.lastname: Pereira
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: André Ricardo
authors.initials: AR
authors.lastname: Massensini
authors.affiliation: Núcleo de Neurociências (NNC), Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais. Av. Antônio Carlos, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Marcio Flávio Dutra
authors.initials: MFD
authors.lastname: Moraes
mesh_terms: D000679:Amygdala / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D003214:Conditioning, Classical / Q000502:physiology*; D004558:Electric Stimulation / Q000379:methods*; D004597:Electroshock; D005239:Fear; D008297:Male; D009474:Neurons / Q000378:metabolism / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D016760:Proto-Oncogene Proteins c-fos
keywords: amygdaloid complex; electrical microstimulation; fear-conditioning; prefrontal cortex; temporal coding