Tag Archives: neuroplasticity

Rats trained to drive makeshift cars seem to find it relaxing

Unlike most of us, rats seem to find driving relaxing.

The impromptu vehicle.
Image credits University of Richmond.

A team of U.S. scientists reports training a group of rats to drive tiny vehicles around in exchange for treats (Froot Loops cereal). The team found hormonal cues suggesting that the animals found driving around to be relaxing, maybe even fun and enjoyable.

The findings help showcase how even simpler brains can handle sophisticated behavior and may help inspire new treatment options for certain mental illnesses.

Rat racers

The team wanted to explore the process of neuroplasticity — the property of the brain to change in response to experience — and was particularly interested in understanding how rats housed in more natural settings perform against lab rats.

Led by senior author Kelly Lambert (University of Richmond), the team took a robot car kit, added a clear plastic food container as the driver’s compartment, and fixed an aluminum plate under that. To complete the car, a copper wire was threaded horizontally across the cab to form a left, center, and right bar.

Image credits: University of Richmond.

When a rat moved onto the aluminum floor and touched one of the wires, it would close the circuit and drive the car in the selected direction. With repetition, they learned how to drive forward and steer in more complex patterns. Seventeen rats were trained over several months to drive around an arena 150 centimeters by 60 centimeters.

All in all, the team reports that rats kept in more natural (‘enriched’) environments performed better than their lab-kept counterparts. However, Lambert herself says it “it was actually quite shocking to me that they were so much better”. In order to get a better idea of what the rats were experiencing, the team collected feces samples after the trials and tested them for corticosterone and dehydroepiandrosterone content (hormones that cause or counter stress).

All of the rats in the trial had higher levels of dehydroepiandrosterone, indicating a more relaxed state. The team says this is likely the same satisfaction we feel when we master a skill or task, known as “self-efficacy” or “agency” in humans. Furthermore, the rats that did drive showed even higher levels of dehydroepiandrosterone than those who were just passengers in a human-controlled vehicle.

While definitely cute, the study does help us better understand how rats, who are a key animal model, handle tasks and how their brains change following them. Better understanding their brains will help us better understand our own, Lambert says, and could point the way towards better treatments for mental health conditions.

“There’s no cure for schizophrenia or depression,” she said. “And we need to catch up, and I think we need to look at different animal models and different types of tasks and really respect that behavior can change our neurochemistry.”

brain

Just half an hour of moderate aerobic exercise can do wonders for the brain

brain

Credit: Pixabay.

Just a brief bout of moderate intensity aerobic exercise can do wonders not only for the body, for the mind as well. Research carried out at the University of Auckland, New Zealand, suggests a half-work workout is enough to promote neuroplasticity or the brain’s ability to reshape itself. In other words, your mind will be fresher, more creative, and ready to learn new things.

Mens sana in corpore sano

The team led by neuroscientist Ronan Mooney recruited ten young adults and asked them to cycle on a stationary treadmill. Some participants worked out moderately, at about 60 percent of their peak performance, while another group stayed idle and acted as the control.

This brief, but intense period of aerobic exercise reduced the levels of the neurotransmitter GABA (gamma-aminobutyric acid) in the brain. GABA is involved in regulating the brain’s capacity to undergo neuroplasticity and when it bind to its receptor sites, the production of a new impulse is prevented and, therefore, has an inhibitory effect.  Because of its inhibitory characteristic, GABA has become a popular medicinal supplement for people that suffer from excessive anxiety. In other situations, reduced GABA levels is a good thing.

“Habitual exercise appears to be beneficial for health and well-being. It is becoming increasingly evident that acute and chronic participation in aerobic exercise exerts a number of positive effects on the brain such as improved memory and executive function. The underlying mechanisms of exercise-related changes in brain function are not completely understood,” said Winston D. Byblow and Ronan A. Mooney of the University of Auckland.

The New Zealand researchers hypothesize that this GABA dynamics followings workouts may “enhance early acquisition and consolidation of skills, leading to improved motor memory and performance.”

Only ten people, all young, were included in this study which was published in Experimental Brain Research. This limits the scope of the findings but future work might examine the effects of exercise on neuroplasticity with a far bigger sample size and varied demographics. Even so, there’s reason to believe stroke victims could benefit immensely from coordinated physical exercise.

Previously, scientists found exercise increases the volume of the hippocampus (the seat of the brain for emotion, memory, and the autonomic nervous system), thus improving memory. Another older study published in 2006 which included only sedentary adults found a six-months aerobic crash course led to an increase of both white and gray matter in the brain. Additionally, exercising keeps depression and dementia at bay.