Learning to make external sensory stimulus predictions using internal correlations in populations of neurons

TL;DR

This study demonstrates that downstream neurons can learn to extract predictive information from neural input correlations using spike timing-dependent learning rules, enabling efficient encoding of sensory predictions without additional instructive signals.

Contribution

It introduces a model showing how downstream neurons can learn to encode predictive sensory information solely from input correlations through spike timing-dependent learning.

Findings

Learned perceptrons transmit position and velocity information efficiently.

Readouts convey nearly all information of optimal readouts.

Predictive information is accessible from neural input correlations.

Abstract

To compensate for sensory processing delays, the visual system must make predictions to ensure timely and appropriate behaviors. Recent work has found predictive information about the stimulus in neural populations early in vision processing, starting in the retina. However, to utilize this information, cells downstream must in turn be able to read out the predictive information from the spiking activity of retinal ganglion cells. Here we investigate whether a downstream cell could learn efficient encoding of predictive information in its inputs in the absence of other instructive signals, from the correlations in the inputs themselves. We simulate learning driven by spiking activity recorded in salamander retina. We model a downstream cell as a binary neuron receiving a small group of weighted inputs and quantify the predictive information between activity in the binary neuron and future input. Input weights change according to spike timing-dependent learning rules during a training period. We characterize the readouts learned under spike timing-dependent learning rules, finding that although the fixed points of learning dynamics are not associated with absolute optimal readouts, they convey nearly all the information conveyed by the optimal readout. Moreover, we find that learned perceptrons transmit position and velocity information of a moving bar stimulus nearly as efficiently as optimal perceptrons. We conclude that predictive information is, in principle, readable from the perspective of downstream neurons in the absence of other inputs, and consequently suggests that bottom-up prediction may play an important role in sensory processing.