Related Experiment Video
Updated: Jun 28, 2026
10:24
Electrophysiological and Morphological Characterization of Neuronal Microcircuits in Acute Brain Slices Using Paired Patch-Clamp Recordings
Published on: January 10, 2015
Firing-pattern-dependent specificity of cortical excitatory feed-forward subnetworks
Takeshi Otsuka1, Yasuo Kawaguchi
1Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki, Aichi 444-8787, Japan.
Summary
Pyramidal neurons in the rat frontal cortex form distinct subnetworks. Layer V pyramidal cells selectively receive inputs from Layer 2/3 cells based on their firing properties, suggesting subtype-specific cortical circuitry.
Area of Science:
- Neuroscience
- Cortical circuitry
- Neuronal networks
Background:
- Pyramidal neurons are key components of the cortical circuit.
- Understanding how these neurons form subnetworks is crucial for deciphering brain function.
- Layer V pyramidal cells exhibit diverse physiological properties.
Purpose of the Study:
- To investigate if pyramidal cells form subnetworks based on their subtypes.
- To determine the input specificity of Layer 2/3 pyramidal cells onto Layer 5 pyramidal cell subtypes.
Main Methods:
- Classification of Layer 5 pyramidal cells into three physiological subtypes (SA, SA-d, FA) based on firing patterns.
- Focal glutamate stimulation of Layer 2/3 pyramidal cells.
- Electrophysiological recordings (dual recordings) to assess synaptic inputs and common input probability.
Main Results:
- Layer 5 pyramidal cell subtypes (SA, SA-d, FA) were identified based on firing adaptation.
- Layer 2/3 pyramidal cells preferentially formed excitatory postsynaptic currents (EPSCs) in SA and SA-d cells over FA cells.
- Topographic interlaminar projections to FA cells were observed, with upper L5 receiving input from upper L2/3 and lower L5 from lower L2/3.
- Common input probability from Layer 2/3 cells was higher between L5 pyramidal cells of the same subtype, indicating selective innervation.
Conclusions:
- Layer 5 pyramidal cells can be physiologically classified into distinct subtypes.
- Layer 2/3 pyramidal cells exhibit selective innervation patterns onto Layer 5 pyramidal cell subtypes.
- These findings suggest the formation of functionally distinct subnetworks within the cortical circuit based on pyramidal cell subtypes.
Related Concept Videos
01:25Neural Circuits
Neural circuits and neuronal pools are two of the main structures found in the nervous system. Neural circuits are networks of neurons that work together to carry out a specific task or process. They consist of interconnected neurons and glial cells, which provide structural and metabolic support.
Neuronal pools are collections of nerve cells with similar functions and interact through chemical and electrical signals. These pools include both interneurons (the central neural circuit nodes that...
Neuronal pools are collections of nerve cells with similar functions and interact through chemical and electrical signals. These pools include both interneurons (the central neural circuit nodes that...
01:19The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.