Synchronization of Neuronal Assemblies in Reciprocally Connected Cortical Areas

Knoblauch, Andreas; Palm, G. Anther

Summary: To investigate scene segmentation in the visual system we present a model of two reciprocally connected visual areas comprising spiking neurons. The peripheral area P is modeled similar to the primary visual cortex, while the central area C is modeled as an associative memory representing stimulus objects according to Hebbian learning. Without feedback from area C, spikes corresponding to stimulus representations in P are synchronized only locally (slow state). Feedback from C can induce fast oscillations and an increase of synchronization ranges (fast state). Presenting a superposition of several stimulus objects, scene segmentation happens on a time scale of hundreds of milliseconds by alternating epochs of the slow and fast state, where neurons representing the same object are simultaneously in the fast state. We relate our simulation results to various phenomena observed in neurophysiological experiments, such as stimulus-dependent synchronization of fast oscillations, synchronization on different time scales, ongoing activity, and attention-dependent neural activity.

FLUCTUATIONS (Physics); TIME measurements; PHYSICAL measurements; VIBRATION (Mechanics)

Theory in Biosciences, 2003, Vol 122, Issue 1, p37

1431-7613

Academic Journal

10.1007/s12064-003-0036-9