Banca de QUALIFICAÇÃO: ANDRE LUIZ VIEIRA LOCKMANN

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ANDRE LUIZ VIEIRA LOCKMANN
DATA : 16/11/2018
HORA: 14:00
LOCAL: INSTITUTO DO CEREBRO
TÍTULO:

Neural oscillations coupling olfactory and hippocampal networks

PALAVRAS-CHAVES:

Local field potentials, respiration-coupled oscillations, beta oscillations, olfactory bulb, hippocampus.

PÁGINAS: 68
GRANDE ÁREA: Ciências Biológicas
ÁREA: Fisiologia
RESUMO:

Local field potentials (LFPs) in the rodent brain exhibit prominent oscillations, which have been suggested to oordinate information flow across neuronal circuits. This thesis investigated oscillations that simultaneously emerge in the rat olfactory and hippocampal systems and supposedly mediate their communication. The main results and insights are presented in four publications – two commentary (1 and 4) and two experimental (2 and 3) papers. Paper 1 discusses the controversial origin of low-frequency LFP oscillations (~ 1 Hz) that appear in the rodent hippocampus during sleep and anesthesia. Do these oscillations reflect internal processing with the neocortex or do they couple to external inputs from rhythmic nasal respiration? This question is experimentally addressed in paper 2. By simultaneously recording nasal respiration and LFPs from urethane-anesthetized rats, we show that the hippocampus exhibits two independent low-frequency oscillations: one that entrains to neocortical “up-and-down” state transitions and another that entrains to the olfactory bulb respiration-coupled rhythm (RR) – and to respiration itself. Paper 3 further shows that the olfactory bulb also drives beta oscillations (10-20 Hz) in the hippocampus. Together, papers 2 and 3 indicate that related network mechanisms generate hippocampal beta and RR: both rhythms are relayed to the hippocampus by entorhinal cortex inputs to the dentate gyrus and, additionally, the phase of RR modulates beta amplitude. Based on our own results and on publications from other groups, in paper 4 we defend that the recently described delta-band oscillations coupling prefrontal cortex and hippocampus correspond to RR. In all, this thesis supports that respiration-coupled and beta oscillations mediate olfacto-hippocampal communication.

MEMBROS DA BANCA:
Presidente - 1721223 - ADRIANO BRETANHA LOPES TORT
Interno - 1728817 - CLAUDIO MARCOS TEIXEIRA DE QUEIROZ
Interno - 2069422 - DIEGO ANDRES LAPLAGNE
Interno - 1996111 - MARTIN PABLO CAMMAROTA