Task-relevant cognitive maps and their role in spatial decision-making

Introduction

One of the hallmarks of our cognition is the ability to decide by thinking several steps ahead using an internal cognitive map. In the wild, map-based decisions can enable animals to select a target location based on the amount of food available and the cost of reaching there.

Research Questions

But how are such decisions made? For example, how does the brain evaluate a nearby location with a small amount of food versus a distal location with more food? What if the route to the distal location is steep?

Unique Nature of Spatial Decisions

Such spatial decisions are unique because evaluating a location depends not only on the learned properties of the location but also on inferred properties, like distance, that are estimated from an internal map. However, where or how in the brain these maps are stored and how they enable spatial decision-making remains unknown.

Specific Aims

Here we will address this question through three specific aims:

1. Reward Site Selection: First, we will test how animals choose among reward sites located at various distances, each dispensing different reward amounts.
2. Cost-Benefit Analysis: Next, we will investigate how animals deduce the costs and benefits associated with different trajectories in an environment to make an informed decision.
3. Internal Cognitive Map Formation: Finally, we will decipher how these internal cognitive maps are formed.

Methodology

These questions will be studied using novel behavior paradigms with rats as the animal model. As rats perform these tasks, simultaneous activity of hundreds of neurons will be recorded from multiple brain regions using novel custom-built devices.

Data Analysis

To study the internal map formation and the mechanism of map-based decision-making, the neural activity will be analyzed using state-of-the-art machine learning techniques.

Causal Role Testing

Finally, the causal role of the corresponding brain regions in spatial decision-making will be tested using optogenetic perturbation experiments.

Conclusion

This multi-disciplinary approach will uncover how the brain makes map-based spatial decisions – a phenomenon that remains unexplored but is of great importance across species.