Coherent phasic excitation during hippocampal ripples.
Neuron
; 72(1): 137-52, 2011 Oct 06.
Article
en En
| MEDLINE
| ID: mdl-21982375
ABSTRACT
High-frequency hippocampal network oscillations, or "ripples," are thought to be involved in episodic memory. According to current theories, memory traces are represented by assemblies of principal neurons that are activated during ripple-associated network states. Here we performed in vivo and in vitro experiments to investigate the synaptic mechanisms during ripples. We discovered postsynaptic currents that are phase-locked to ripples and coherent among even distant CA1 pyramidal neurons. These fast currents are consistent with excitatory postsynaptic currents (EPSCs) as they are observed at the equilibrium potential of Cl(-), and they display kinetics characteristic of EPSCs. Furthermore, they survived after intracellular blockade of GABAergic transmission and are effective to regulate the timing of action potentials. In addition, our data show a progressive synchronization of phasic excitation and inhibition during the course of ripples. Together, our results demonstrate the presence of phasic excitation during ripples reflecting an exquisite temporal coordination of assemblies of active pyramidal cells.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Potenciales de Acción
/
Células Piramidales
/
Potenciales Postsinápticos Excitadores
/
Ondas Encefálicas
/
Hipocampo
Límite:
Animals
Idioma:
En
Año:
2011
Tipo del documento:
Article