Abstract
A critical step in understanding the neural basis of human cognitive functions is to identify neuronal types in the neocortex. In this study, we performed whole-cell recording from human cortical slices andfound a distinct subpopulation of neurons with intrinsic persistent activity that could be triggered by single action potentials (APs) but terminated by bursts of APs. This persistent activity was associated with a depolarizing plateau potential induced by theactivation of a persistent Na+ current. Single-cell RT-PCR revealed that these neurons were inhibitory interneurons. This type of neuron was found in different cortical regions, including temporal, frontal, occipital, and parietal cortices in human and also infrontal and temporal lobes of nonhuman primate but not in rat cortical tissues, suggesting that it could be unique to primates. The characteristic persistentactivity in these inhibitory interneurons may contribute to the regulation of pyramidal cell activity and participate in cortical processing.
Highlights
Individual neurons in the central nervous system evaluate synaptic inputs and transform them into the main output signal, the action potential (AP), following a computational function mainly determined by their electrical properties and morphological features
Persistent Activity Can Be Triggered by Single APs In a subpopulation of neurons examined in human slices, we found that single APs evoked by brief (0.5 $ 2 ms) current pulses triggered persistent firing, i.e., persistent activity, when the Vm was maintained just below the firing threshold (Figures 1A–1C)
1450 Cell Reports 10, 1450–1458, March 10, 2015 a2015 The Authors. The somata of these persistent-activity neurons (PANs) were not pyramid shaped, suggesting that they might represent a subtype of interneuron in the human cortex
Summary
Individual neurons in the central nervous system evaluate synaptic inputs and transform them into the main output signal, the action potential (AP), following a computational function mainly determined by their electrical properties and morphological features. In addition to the great expansion of cortical volume during evolution, unique cell types in the human neocortex may contribute to its versatile mental abilities. The Von Economo neurons (VENs) with distinct morphological characters have only been found in large-brained mammals, including human and nonhuman primates (Economo and Parker, 1929; Evrard et al, 2012; Nimchinsky et al, 1999). This specialized cell type may contribute to the rapid transmission of social information and self-awareness (Allman et al, 2005; Seeley et al, 2006). Except for the finding of VENs, the search for unique cell types in the human neocortex turns out to be unfruitful
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
