Synchronization and coordination of sequences in two neural ensembles

Area of Science:

• Neuroscience
• Computational Biology
• Systems Biology

Background:

• Sequential motor behavior in animals relies on neural networks.
• Higher animals use the central nervous system (CNS) for coordination, while invertebrates often use direct synaptic connections.
• Statocysts, gravity sensory organs in marine mollusks like Clione, are crucial for postural control and motor programs.

Purpose of the Study:

• To investigate how electrotonic synapses can coordinate chaotic sequential activity in small model neural networks.
• To analyze the synchronization of two model statocyst networks in the marine mollusk Clione.
• To understand the role of electrical coupling in synchronizing neural circuits with inherent chaotic dynamics.

Main Methods:

• Modeling two statocyst neural networks with Lotka-Volterra dynamics and non-symmetric inhibitory interactions.
• Simulating the synchronization of these networks using electrical coupling.
• Introducing an external signal leading to winnerless competition among neurons.

Main Results:

• Electrical coupling between neural networks can coordinate and synchronize their inherently chaotic sequential activity.
• The degree of coordination is dependent on the number and strength of connections between the networks.
• Synchronization is achieved through an activation sequence lock, even amidst chaotic dynamics.

Conclusions:

• Electrotonic synapses are effective in coordinating chaotic neural network dynamics.
• This mechanism provides a way to achieve synchronized sequential motor behavior in systems lacking complex CNS control.
• The findings offer insights into the principles of neural coordination in invertebrates and simple biological systems.