Adaptive Drift-Diffusion Process to Learn Time Intervals

TL;DR

This paper introduces a novel adaptive drift-diffusion model for learning time intervals that does not rely on traditional clock mechanisms, accurately capturing timing behavior with simple integrators and geometric learning rules.

Contribution

The paper presents a new interval timing model based on drift-diffusion processes that learns intervals efficiently without requiring clocks or complex neural structures.

Findings

Model learns intervals in a fixed number of trials regardless of length

Temporal precision is proportional to the interval size

Model makes three testable predictions

Abstract

Animals learn the timing between consecutive events very easily. Their precision is usually proportional to the interval to time (Weber's law for timing). Most current timing models either require a central clock and unbounded accumulator or whole pre-defined populations of delay lines, decaying traces or oscillators to represent elapsing time. Current adaptive recurrent neural networks fail at learning to predict the timing of future events (the 'when') in a realistic manner. In this paper, we present a new model of interval timing, based on simple temporal integrators, derived from drift-diffusion models. We develop a simple geometric rule to learn 'when' instead of 'what'. We provide an analytical proof that the model can learn inter-event intervals in a number of trials independent of the interval size and that the temporal precision of the system is proportional to the timed interval. This new model uses no clock, no gradient, no unbounded accumulators, no delay lines, and has internal noise allowing generations of individual trials. Three interesting predictions are made.