# Retroactive Interference Model of Power-Law Forgetting

## TL;DR

This paper introduces a simple, analytically solvable model based on retroactive interference to explain power-law forgetting, aligning well with experimental data on memory stability over time.

## Contribution

It presents a novel phenomenological model of forgetting that is based on retroactive interference and can be analytically solved with only one parameter.

## Key findings

- Model accurately fits recognition experiment data
- Forgetting follows a power-law relationship with time
- Old memories are more stable than younger ones in the model

## Abstract

Memory and forgetting constitute two sides of the same coin, and although the first has been rigorously investigated, the latter is often overlooked. A number of experiments under the realm of psychology and experimental neuroscience have described the properties of forgetting in humans and animals, showing that forgetting exhibits a power-law relationship with time. These results indicate a counter-intuitive property of forgetting, namely that old memories are more stable than younger ones. We have devised a phenomenological model that is based on the principle of retroactive interference, driven by a multi-dimensional valence measure for acquired memories. The model has only one free integer parameter and can be solved analytically. We performed recognition experiments with long streams of words were performed, resulting in a good match to a five-dimensional version of the model.