In an era of brain scans, EEGs, and AI models, maze experiments can feel a little outdated. Despite their air of antiquity, however, these maze tools are highly effective for probing cognition, memory, and decision-making. 

Since 1901, when experimental psychologist Willard Small built the first rodent maze inspired by Hampton Court Palace, researchers have used labyrinths to observe behavior and dissect the mechanisms behind it. One of the earliest breakthroughs came in 1907 with psychologist John B. Watson’s “ kerplunk experiment. ” In this study, Watson systematically eliminated different senses in rats to see how this deletion affected their ability to run a straight alley maze. Surprisingly, even when vision, smell, and other senses were impaired, the rats still completed the maze successfully. When the maze was shortened, the rats ran the original distance and collided with the end wall, producing the “kerplunk” sound that gave the study its name. 

This wasn’t just a quirky behavioral finding, but also marked a fundamental change in how scientists understood navigation and learning. The rats weren’t relying on external sensory cues, but instead on internal feedback from their own movements. Watson’s work helped establish the concept of egocentric navigation , where animals use motor habits, proprioception (the body’s sense of its own position), and kinesthetic feedback (awareness of one’s movements) to guide behavior. It was one of the first indications that memory and learning could be rooted in the body’s own spatial awareness.

This wasn’t just a quirky behavioral finding, but also marked a fundamental change in how scientists understood navigation and learning.

As maze designs evolved, researchers began exploring a different kind of navigation: the allocentric strategy . This movement method relies on building an internal “map” of the environment, more like a third-person perspective. The Morris Water Maze , designed by Richard Morris in 1981, became the classic tool for studying this process. In this task, rats are placed in a circular pool of water and must locate a hidden escape platform. With no immediate cues pointing to the platform’s location, the animals must rely on spatial relationships among external landmarks to succeed. Findings from this paradigm highlighted the hippocampus — a brain structure critical for memory formation — as a key component of spatial memory. These studies also clarified how allocentric navigation connects to the broader distinction between declarative memory (knowing facts and places) and procedural memory (knowing habits and skills).

Building on these classic designs, more recent maze paradigms have tried to capture something closer to the complexity of everyday memory. One approach uses medium-sized mazes that remain fixed in their overall layout but contain components that change from day to day. In these tasks, rodents are often pre-trained on a simple rule: while the location of the reward may change each day, once the animal discovers the reward during a session, that location stays the same. The real experiment begins only after the animals master this rule, so that their performance reflects their ability to acquire new information rather than relearn familiar patterns. An example includes cheeseboard mazes , where a board contains many wells and the reward (a piece of cheese) can be moved daily.

These modern maze designs reveal a fascinating tension. While they are built to engage the hippocampus and test memory, animals often develop shortcuts that convert the task into procedural skills over time. In doing so, these mazes not only model the neural basis of everyday memory but also highlight how brains constantly balance flexibility with efficiency. 

Mazes not only model the neural basis of everyday memory but also highlight how brains constantly balance flexibility with efficiency.

From the “kerplunk” of rats relying on motor habits to hippocampal maps revealed in the Morris Water Maze, maze experiments have steadily deepened our understanding of how brains learn, adapt, and automate. Together, they show that behavior is not just a matter of stimulus and response, but of habits, spatial maps, and flexible memory working in tandem to face the challenge at hand. In an age of cognitive imaging built on complex computational models, the humble maze continues to reveal how cognition unfolds in the most practical sense: how we learn, remember, and decide.