Bursting Neurons in the Hippocampal Formation Encode Features of LFP Rhythms

• Autores: Constantinou, Maria; Gonzalo Cogno, Ximena Soledad; Elijah, Daniel H.; Kropff, Emilio; Gigg, John; Samengo, Ines; Montemurro, Marcelo A.
• Año de publicación: 2016
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: BURSTING; ENTORHINAL CORTEX; INFORMATION THEORY; LOCAL FIELD POTENTIAL; NEURAL CODING; SUBICULUM
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Burst spike patterns are common in regions of the hippocampal formation such as the subiculum and medial entorhinal cortex (MEC). Neurons in these areas are immersed in extracellular electrical potential fluctuations often recorded as the local field potential (LFP). LFP rhythms within different frequency bands are linked to different behavioral states. For example, delta rhythms are often associated with slow-wave sleep, inactivity and anesthesia; whereas theta rhythms are prominent during awake exploratory behavior and REM sleep. Recent evidence suggests that bursting neurons in the hippocampal formation can encode LFP features. We explored this hypothesis using a two-compartment model of a bursting pyramidal neuron driven by time-varying input signals containing spectral peaks at either delta or theta rhythms. The model predicted a neural code in which bursts represented the instantaneous value, phase, slope and amplitude of the driving signal both in their timing and size (spike number). To verify whether this code is employed in vivo, we examined electrophysiological recordings from the subiculum of anesthetized rats and the MEC of a behaving rat containing prevalent delta or theta rhythms, respectively. In both areas, we found bursting cells that encoded information about the instantaneous voltage, phase, slope and/or amplitude of the dominant LFP rhythm with essentially the same neural code as the simulated neurons. A fraction of the cells encoded part of the information in burst size, in agreement with model predictions. These results provide in-vivo evidence that the output of bursting neurons in the mammalian brain is tuned to features of the LFP.
Fil: Constantinou, Maria. University of Manchester; Reino Unido
Fil: Gonzalo Cogno, Ximena Soledad. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Elijah, Daniel H.. University of Manchester; Reino Unido
Fil: Kropff, Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina
Fil: Gigg, John. University of Manchester; Reino Unido
Fil: Samengo, Ines. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Montemurro, Marcelo A.. University of Manchester; Reino Unido