Asynchronous Segregation of Cortical Circuits and Their Function: A Life-long Role for Synaptic Death

Yoram Baram; Yoram Baram

doi:10.3934/Neuroscience.2017.2.87

AIMS Neuroscience

2017, Volume 4, Issue 2: 87-101. doi: 10.3934/Neuroscience.2017.2.87

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Research article Special Issues

Asynchronous Segregation of Cortical Circuits and Their Function: A Life-long Role for Synaptic Death

Yoram Baram ^,

Computer Science Department, Technion- Israel Institute of Technology Haifa 32000, Israel

Received: 13 March 2017 Accepted: 03 May 2017 Published: 09 May 2017

The functional role of synapse elimination has been debated since its discovery nearly three decades ago. Its widely perceived function in the removal of unnecessary and malfunctioning synapses in early life for the improvement of neural circuit performance has justified the term “synaptic pruning”. Yet, while recent experimental findings suggest the persistence of synaptic elimination into maturity and beyond, its cause and functionality have remained a mystery. Here we show that synapse elimination, caused by asynchronous neural firing, segregates individual neurons and neural circuits into interference-free synchronous isolation. Such segregation is shown to determine not only the circuit sizes, but also the circuit firing rate modes, fundamental to a large variety of cortical functions throughout life.
- synapse elimination,
- synaptic pruning,
- neural circuits,
- developmental plasticity,
- cortical circuit segregation
Citation: Yoram Baram. Asynchronous Segregation of Cortical Circuits and Their Function: A Life-long Role for Synaptic Death[J]. AIMS Neuroscience, 2017, 4(2): 87-101. doi: 10.3934/Neuroscience.2017.2.87

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Abstract

The functional role of synapse elimination has been debated since its discovery nearly three decades ago. Its widely perceived function in the removal of unnecessary and malfunctioning synapses in early life for the improvement of neural circuit performance has justified the term “synaptic pruning”. Yet, while recent experimental findings suggest the persistence of synaptic elimination into maturity and beyond, its cause and functionality have remained a mystery. Here we show that synapse elimination, caused by asynchronous neural firing, segregates individual neurons and neural circuits into interference-free synchronous isolation. Such segregation is shown to determine not only the circuit sizes, but also the circuit firing rate modes, fundamental to a large variety of cortical functions throughout life.

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