Structural and functional specializations of human fast-spiking neurons support fast cortical signaling.
Sci Adv
; 9(41): eadf0708, 2023 10 13.
Article
em En
| MEDLINE
| ID: mdl-37824618
ABSTRACT
Fast-spiking interneurons (FSINs) provide fast inhibition that synchronizes neuronal activity and is critical for cognitive function. Fast synchronization frequencies are evolutionary conserved in the expanded human neocortex despite larger neuron-to-neuron distances that challenge fast input-output transfer functions of FSINs. Here, we test in human neurons from neurosurgery tissue, which mechanistic specializations of human FSINs explain their fast-signaling properties in human cortex. With morphological reconstructions, multipatch recordings, and biophysical modeling, we find that despite threefold longer dendritic path, human FSINs maintain fast inhibition between connected pyramidal neurons through several mechanisms stronger synapse strength of excitatory inputs, larger dendrite diameter with reduced complexity, faster AP initiation, and faster and larger inhibitory output, while Na+ current activation/inactivation properties are similar. These adaptations underlie short input-output delays in fast inhibition of human pyramidal neurons through FSINs, explaining how cortical synchronization frequencies are conserved despite expanded and sparse network topology of human cortex.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neocórtex
/
Neurônios
Limite:
Humans
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article