Interanalyzer two-way neuronal connections during alimentary conditioning in cats

Area of Science:

• Neuroscience
• Systems Neuroscience
• Computational Neuroscience

Background:

• Neural plasticity underlies learning and memory formation.
• Understanding interneuronal communication is crucial for deciphering brain function.
• The visual and sensorimotor cortices play key roles in sensory processing and motor control.

Purpose of the Study:

• To investigate changes in interneuronal connectivity within and between visual and sensorimotor cortices during the acquisition of a conditioned reflex.
• To identify specific neuronal populations that exhibit altered network properties following learning.

Main Methods:

• Chronic implantation of recording electrodes in the visual and sensorimotor cortices of four cats.
• Recording of multineuronal activity during low-frequency electrostimulation of optic tracts.
• Statistical analysis of intra- and interanalyzer interneuronal connections using cross-correlograms.
• Comparison of neuronal network properties in untrained versus trained animals.

Main Results:

• Acquisition of a conditioned reflex led to a significant increase in one-way and two-way interneuronal connections, both intra- and interanalyzer.
• Neurons with intermediate amplitude spikes showed the most pronounced changes in network properties, gaining more incoming and outgoing connections.
• The overall increase in interneuronal connections post-training was primarily driven by enhanced connections from the sensorimotor to the visual analyzer.

Conclusions:

• Learning induces substantial alterations in the functional connectivity of the visual and sensorimotor cortices.
• Specific neuronal populations, identified by intermediate spike amplitudes, are dynamically recruited into learned networks.
• The sensorimotor cortex plays an increasingly important role in modulating visual processing during conditioned reflex acquisition.