Article
Neurosciences
Antoine Carton-Leclercq, Sofia Carrion-Falgarona, Paul Baudin, Pierre Lemaire, Sarah Lecas, Thomas Topilko, Stephane Charpier, Severine Mahon
Summary: The study investigates the laminar expression of cortical activities induced by transient anoxia in the rat primary somatosensory cortex. It reveals a well-organized sequence of activity patterns across cortical layers after the interruption of brain oxygenation. The onset and propagation of anoxic depolarization (AD) show layer-dependent variations, while the repolarization of cortical neurons upon reoxygenation does not exhibit a specific spatio-temporal profile.
NEUROBIOLOGY OF DISEASE
(2023)
Article
Neurosciences
Arik Shvartsman, Oron Kotler, Ohad Stoler, Yana Khrapunsky, Israel Melamed, Ilya A. Fleidervish
Summary: Cortical pyramidal neurons have a persistent Na+ current (I-NaP) which plays an important role in neuronal input-output processing. The study reveals the subcellular distribution and mechanisms underlying the persistent Na+ current, showing that most I-NaP originates from the axon initial segment. Furthermore, endogenous polyamines constrain I-NaP availability in non-dialyzed cortical neurons.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Neurosciences
Najoua Biba-Maazou, Helene Becq, Emilie Pallesi-Pocachard, Stefania Sarno, Samuel Granjeaud, Aurelie Montheil, Marie Kurz, Laurent Villard, Mathieu Milh, Pierre-Pascal Lenck Santini, Laurent Aniksztejn
Summary: Mutations in the KCNQ2 gene can cause developmental and epileptic encephalopathy, affecting the electrophysiological properties of brain cells at different developmental stages, but the effects vary during the course of development.
JOURNAL OF PHYSIOLOGY-LONDON
(2022)
Article
Biochemistry & Molecular Biology
Victor N. Ierusalimsky, Pavel M. Balaban, Evgeny S. Nikitin
Summary: Electrophysiological and genetic studies have identified two major subclasses of L5 neocortical pyramidal neurons, with one subclass expressing KCa3.1 channels and the other exhibiting weak afterhyperpolarization. This study demonstrates that Nav1.6 channels, rather than KCa3.1 channels, have an impact on the threshold, dynamics, and coding abilities of these neurons. The findings suggest a link between Nav1.6 function and the ability of L5 neurons to encode high frequencies.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
(2022)
Article
Biology
Brian A. Cary, Gina G. Turrigiano
Summary: In juvenile rats, sleep and wake states did not significantly drive changes in synaptic strength within the neocortex. The synaptic strength remained stable across sleep and wake periods, suggesting that sleep does not lead to widespread downscaling of synaptic strengths in juvenile animals. It remains to be seen whether this stability across sleep and wake generalizes to the fully mature nervous system.
Article
Neurosciences
John F. Enwright, Dominique Arionl, William A. MacDonald, Rania Elbakri, Yinghong Pan, Gopi Vyas, Annerose Berndt, David A. Lewis
Summary: There are regional differences in the transcriptome of layer 3 pyramidal neurons in the visual spatial working memory network. These differences may contribute to the regional specialization in their morphological and physiological features and their functional contributions to visual spatial working memory.
Article
Neurosciences
Yizhen Z. Zhang, Stella Sapantzi, Alice Lin, Savannah R. Doelfel, Barry W. Connors, Brian B. Theyel
Summary: This study found that a large proportion of neocortical pyramidal cells in mice are capable of firing ectopic action potentials (EAPs) in vitro. These cells can integrate information over long time-scales before briefly entering a mode of self-generated firing that originates in distal axons. The surprising ubiquity of EAP generation in these cells raises interesting questions about its potential roles in information processing, cortical oscillations, and seizure susceptibility.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2023)
Article
Neurosciences
Sabrina Tazerart, Maxime G. Blanchard, Soledad Miranda-Rottmann, Diana E. Mitchell, Bruno Navea Pina, Connon I. Thomas, Naomi Kamasawa, Roberto Araya
Summary: Dendritic spines are the main receptor of excitatory information in the brain, and their unique morphology has an impact on the processing, storage, and integration of synaptic inputs in pyramidal neurons. This study found that large conductance calcium-activated potassium (BK) channels are present in dendrites and spines regardless of their size, but they are only active in spines with small head volumes. Additionally, calcium signals in spines with small head volumes are significantly larger than those in spines with larger head volumes. Experimental data and numerical simulations suggest that synaptic inputs onto spines with small head volumes generate larger voltage and calcium signals, sufficient to activate BK channels and suppress excitatory postsynaptic potentials.
JOURNAL OF PHYSIOLOGY-LONDON
(2022)
Article
Cell Biology
Anna R. Chambers, Christoffer Nerland Berge, Koen Vervaeke
Summary: The hippocampus conveys memory-related neural patterns during high-frequency oscillations called sharp-wave ripples (SWRs). The study found that before SWRs, there is a decrease in superficial inhibition and thalamocortical input in the retrosplenial cortex (RSC). This may aid in communication between the hippocampus and neocortex and promote the strengthening of memory-related connections.
Article
Anatomy & Morphology
Edmund T. Rolls
Summary: Research suggests that neocortical pyramidal cells can simultaneously implement unsupervised learning, short-term memory, and recall functions through interactions with inputs from the previous cortical area and the following cortical area, achieving these three major types of computation.
BRAIN STRUCTURE & FUNCTION
(2021)
Article
Mathematics, Interdisciplinary Applications
Miaomiao Xing, Xinlin Song, Hengtong Wang, Zhuoqin Yang, Yong Chen
Summary: This work studies the response dynamics of a two-neuron network motif composed of class-1 and class-3 Morris-Lecar neurons under an external directional current. The study finds that the two neurons exhibit frequency locking and complete frequency synchronization with increases in coupling strength and input current. The class-3 neuron in the motif can produce various excitabilities with appropriate coupling strength and input current, including tonic and phasic spiking.
CHAOS SOLITONS & FRACTALS
(2022)
Article
Neurosciences
Elena Spoleti, Paraskevi Krashia, Livia La Barbera, Annalisa Nobili, Carmen Alina Lupascu, Elisabetta Giacalone, Flavio Keller, Michele Migliore, Massimiliano Renzi, Marcello D'Amelio
Summary: This study reveals that impaired cell excitability and firing in ventral CA1 pyramidal neurons is an early feature in Tg2576 AD mice.
EXPERIMENTAL NEUROLOGY
(2022)
Article
Biology
Vera Valakh, Derek Wise, Xiaoyue Aelita Zhu, Mingqi Sha, Jaidyn Fok, Stephen D. Van Hooser, Robin Schectman, Isabel Cepeda, Ryan Kirk, Sean M. O'Toole, Sacha B. Nelson
Summary: Healthy neuronal networks require homeostatic plasticity to maintain stable firing rates. However, inappropriate or excessive activation of these mechanisms can lead to destabilization and rebound hyperactivity. In this study, the negative regulation of cortical network homeostasis by the PARbZIP family of transcription factors was uncovered. Knockout mice lacking these factors showed a stronger network response to activity withdrawal, indicating their critical role in constraining plasticity and preventing seizures.
Article
Biochemical Research Methods
Toviah Moldwin, Menachem Kalmenson, Idan Segev
Summary: This study explores the importance and application potential of synaptic clustering on neuronal dendrites in pattern recognition, proposing two models - single-branch clusteron and gradient clusteron - which utilize structural plasticity and functional plasticity to solve classification tasks. Experimental results demonstrate that the gradient clusteron achieves decent accuracy on the MNIST dataset tasks.
PLOS COMPUTATIONAL BIOLOGY
(2021)
Article
Developmental Biology
Jessica Alves Medeiros de Araujo, Soraia Barao, Isabel Mateos-White, Ana Espinosa, Marcos Romualdo Costa, Cristina Gil-Sanz, Ulrich Mueller
Summary: ZBTB20 is involved in specifying a subset of callosal projection neurons in mouse cortex, with its deletion leading to an increase in layer IV neurons at the expense of layer II/III neurons. Astrogliogenesis is also affected, especially in mutants with ZBTB20 mutations linked to Primrose syndrome, indicating ZBTB20's role in instructing astrogliogenesis with other ZBTB proteins.