# Computational modeling reveals cognitive processes in simple rodent depression tests

## TL;DR

Researchers developed a new method to analyze rodent depression tests, revealing that different cognitive processes drive behavior in these tests and change over time.

## Contribution

A novel computational framework with automated tracking and modeling reveals distinct cognitive processes in depression-like behavior tests.

## Key findings

- Forced swim and tail suspension tests involve partially distinct cognitive processes.
- Cognitive drivers shift from learning to consequence sensitivity over time during the tests.

## Abstract

Simple behavioral tests like the forced swim test (FST) and tail suspension test (TST) are widely used to assess depression-like behaviors in rodents, primarily measuring immobility time. However, this approach can oversimplify behavioral readouts and obscure cognitive processes driving behavior, leaving the relationship between increased immobility and cognitive biases unclear. Here, we developed the SwimStruggleTracker (SST) to extract fine-grained behavioral trajectories and integrate computational modeling to systematically analyze behavior. Our findings show that behavior in the FST and TST follows reinforcement learning principles involving learning, consequence perception, and decision-making. Notably, the cognitive processes underlying behavior differ between the two tests, challenging the assumption that they are interchangeable for cross-validation. Regression analyses identify distinct behavior phases: early behavior is primarily influenced by learning-related factors, while later stages are more affected by consequence sensitivity. These findings suggest that traditional analyses may underestimate the role of learning and overemphasize consequence sensitivity.

•We develop computational models to analyze depression behavior tests in mouse•SwimStruggleTracker (SST) robustly filters out passive movements•Forced swim and tail suspension tests involve partially distinct cognitive processes•Cognitive drivers shift from learning to consequence sensitivity over time

We develop computational models to analyze depression behavior tests in mouse

SwimStruggleTracker (SST) robustly filters out passive movements

Forced swim and tail suspension tests involve partially distinct cognitive processes

Cognitive drivers shift from learning to consequence sensitivity over time

The forced swim test (FST) and tail suspension test (TST) are among the most widely used paradigms for assessing depression-like behaviors in rodents. Yet, traditional analyses typically quantify only immobility during the final minutes, discarding rich temporal structure in the data and hindering efforts to uncover the cognitive mechanisms underlying these behaviors. To address this gap, we developed an automated tool that captures behavioral trajectories with fine temporal resolution and integrates computational modeling to dissect the cognitive processes driving behavior. Using this approach, we demonstrate that the FST and TST engage overlapping but partially distinct cognitive processes and that the dominant cognitive components shift across different stages of the tests.

Li et al. present a framework integrating automated behavioral tracking and computational modeling to dissect mouse depression tests. They reveal that the forced swim and tail suspension tests engage overlapping but partially distinct cognitive processes and that the dominant cognitive components shift across different stages of the tests.