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In a groundbreaking study has identified the termed “step tracker” within the human brain by monitoring the neural activity of rodents on the move.

The team let the subjects to move inside a specially designed enclosure and recorded signals from a neural area known to be essential for navigation and memory formation.

It was found that cells in that region responded in a sequence that mirrored a step tracker—ticking with each stride the rat took.

An additional experiment with human volunteers moving through a larger version of the rodent experiment pointed to the our brains contain the same built-in mechanism.

Brain Fog

Picture moving back and forth your cooking area and main area, said principal investigator Prof James Ainge. These cells reside in the part of the head that supplies that mental layout—the ability to put yourself in the world through thought.

This research give insight into how that internal map works—and what occurs when it malfunctions. After altering the rhythm of that step tracker by adjusting the surroundings, both animals and humans begin failing to estimate distance.

During everyday experiences, this takes place in darkness, or when mist descends while walking. Unexpectedly turns more difficult to gauge how far we have moved, because our neural mileage counter ceases functioning reliably.

In order to test, scientists prepared rats to run a fixed length in a box-shaped space—rewarding the subjects with a treat (some chocolate cereal) when they ran the right length and came back to the start.

As the subjects moved the correct distance, the mileage-counting cells in their brains fired regularly—about every a third of a meter a animal moved.

The more regular that neural activity appeared, the more accurate the animals performed in estimating the length they had to cover to obtain that treat, explained the scientist.

Researchers managed to monitor the brain's internal counter registering the length the animal had covered.

Significantly, when the team modified the design of the rat arena, that steady brain signal became irregular and the rats found it hard to calculate how far they needed to move before heading back to the start for their chocolate treat.

It's fascinating, commented the researcher. The animals display this sort of consistent shortfall. It seems about the reality that the signal lacks consistency that causes them stopping early.

Researchers equated this to familiar sights suddenly fading in the fog.

Obviously it's tougher to navigate in mist, but perhaps fail to realize is that it also impairs our ability to estimate how far.

In order to confirm, the researchers scaled up their small-scale trial. They created a 12m x 6m space and instructed volunteers to carry out the same activity as the rodents—traveling a predetermined length, then returning to the origin.

Just like rats, volunteers were regularly able to judge the distance accurately when they were in a uniform, enclosed environment. But when the researchers adjusted the boundaries of their specially designed area to change its layout, the volunteers started getting it wrong.

The two groups master the distance estimation test really well, then, when you change the environment in the manner that we know distorts the rhythm in the rats, you observe a very similar behavioural pattern in people, stated Prof Ainge.

Along with uncovering something core about how our minds allow us to move, the scientists say the discoveries could assist in diagnosing Alzheimer's Disease.

Certain neurons we're recording from are in among the earliest areas that's damaged in dementia, explained the researcher. Researchers have already developed diagnostic tools that you can use on your mobile device, for instance, to test navigation. We'd be extremely interested in attempting something similar, but exclusively looking at how far we think we've gone.