Dynamic control for synchronization of separated cortical areas through thalamic relay

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• Cortical areas process information and integrate features via neural synchrony.
• Long delays between cortical areas pose challenges for achieving synchrony.
• The role of the thalamus in mediating cortical synchrony remains an active area of research.

Purpose of the Study:

• To investigate the dynamics and synchronization properties of a simplified thalamocortical circuit model.
• To explore the potential of the thalamus to generate zero-lag synchrony between distant cortical areas.
• To propose a control mechanism for switching cortical synchrony on and off.

Main Methods:

• Utilized a simplified computational model of the thalamocortical circuit.
• Incorporated delays longer than neuronal timescales between interconnected cortical areas.
• Simulated external input using independent Poisson trains to the thalamus.
• Investigated the effect of varying input rates to dorsal and ventral thalamic populations.

Main Results:

• The model demonstrated that the thalamus can act as a central subcortical hub generating zero-lag synchrony between distant cortical areas via dynamical relaying.
• Fast oscillations in beta and gamma frequency bands were observed, triggered by external thalamic input.
• A control mechanism was identified, enabling dynamic switching of synchronization between cortical areas based on relative input rates.

Conclusions:

• The thalamus plays a critical role in controlling the dynamics of thalamocortical functional networks.
• The thalamus can enable or disable zero-lag synchrony between separated cortical areas on a fast timescale.
• This thalamus-mediated control of synchrony operates without requiring slow plasticity or adaptation mechanisms.