Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of Graph Search.
Concept
Central pattern generator
Summary
Central pattern generators (CPGs) are self-organizing biological neural circuits that produce rhythmic outputs in the absence of rhythmic input. They are the source of the tightly-coupled patterns of neural activity that drive rhythmic and stereotyped motor behaviors like walking, swimming, breathing, or chewing. The ability to function without input from higher brain areas still requires modulatory inputs, and their outputs are not fixed. Flexibility in response to sensory input is a fundamental quality of CPG-driven behavior. To be classified as a rhythmic generator, a CPG requires:
"two or more processes that interact such that each process sequentially increases and decreases, and
that, as a result of this interaction, the system repeatedly returns to its starting condition."
CPGs have been found in invertebrates, and practically all vertebrate species investigated, including humans.
CPG neurons can have different intrinsic membrane properties (see schematic). Some neurons fire bursts of action potentials, either endogenously or in the presence of neuromodulatory substances. Other neurons are bistable and generate plateau potentials that can be triggered by a depolarizing current pulse, and terminated by a hyperpolarizing current pulse. Many CPG neurons fire after being released from inhibition (postinhibitory rebound). Another common feature of CPG neurons is a decrease in the frequency of firing during a constant depolarization (spike frequency adaptation).
Rhythm generation in CPG networks depends on the intrinsic properties of CPG neurons and their synaptic connections. There are two general mechanisms for rhythm generation: pacemaker/follower and reciprocal inhibition (see schematic).
In a network driven by a pacemaker, one or more neurons act as a core oscillator (pacemaker) that drives other, non-bursting neurons (follower) into a rhythmic pattern. Examples of pacemaker driven networks include the pyloric rhythm of the crustacean stomatogastric ganglion and the vertebrate respiratory rhythms.
Official source
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.