Neurons hard wired to tell left from right

March 31, 2008

It's well known that the left and right sides of the brain differ in many animal species and this is thought to influence cognitive performance and social behaviour. For instance, in humans, the left half of the brain is concerned with language processing whereas the right side is better at comprehending musical melody.

Now researchers from UCL publishing their work in the open access journal Neural Development have pinpointed for the first time the left/right differences in how brains are wired at the level of individual cells. To do this, a research team led by Stephen Wilson looked at left and right-sided neurons (nerve cells) in a part of the brain called the habenula.

By causing habenular neurons to produce a bright green fluorescent protein they saw that they form remarkable "spiral-shaped" axons, the long nerve fibres that act as the nervous system's transmission lines.

"It's clear that the left and right halves of the brain process different types of information but almost nothing is known about the differences in the brain's circuitry which achieve this" says Wilson. "One possibility is that totally different types of neuron might be found on the left and right. Alternatively, both sides could contain the same building blocks but put them together in different ways".

The researchers saw that there are two types of habenular neuron and both types can be found on both left and right sides. However, whilst most left-sided cells have spiral axons shaped into a domed crown, such neurons are not very common on the right. Instead, most right-sided cells form flat, shallow spirals, and these are formed only occasionally on the left.

"In the same way that an engineer can make different electronic circuits from the same set of electronic components, so the left and right halves of the brain use the same types of neuron but in different combinations" explains Isaac Bianco, the student who did this work as part of his PhD studies.

The left and right habenular circuits both connect to the same part of the brain and the researchers found that this target can either combine signals from the left and right or handle them independently.

"Even though language is processed largely on the left side of the human brain, people don't speak with only one half of their mouth. The brain must contain circuits which take information from the left or right and then send it on to targets on both sides of the body" says Wilson.

Source: BioMed Central

Explore further: The brain auditions different cells when learning a task, some don't make the cut

Related Stories

The brain auditions different cells when learning a task, some don't make the cut

November 14, 2017
For decades, neuroscientists have wondered how the brain can continue to learn new skills without needing to grow in size or volume over a person's lifetime. Evidence suggests that the number of brain cells - such as neurons ...

Discovery of a promising medication for amyotrophic lateral sclerosis

November 16, 2017
Researchers from the University of Montréal Hospital Research Centre (CRCHUM) and the Cumming School of Medicine (CSM) at the University of Calgary have discovered a medication that could make it possible to treat individuals ...

Liquid biopsy spots aggressive pediatric brainstem cancer earlier without surgery

November 6, 2017
A particularly aggressive form of pediatric cancer can be spotted reliably by the genetic fragments it leaves behind in children's biofluids, opening the door to non-surgical biopsies and providing a way to gauge whether ...

Student uses drone imaging for hurricane relief effort in Texas

October 26, 2017
She tried to hold back tears as she approached her husband and the insurance adjuster taking stock of the few belongings they had left after Hurricane Harvey made landfall. Her efforts to contain her emotions failed as the ...

Brain-machine interfaces to treat neurological disease

October 18, 2017
Since the 19th century at least, humans have wondered what could be accomplished by linking our brains – smart and flexible but prone to disease and disarray – directly to technology in all its cold, hard precision. Writers ...

An especially challenging brain cancer diagnosis

August 24, 2017
Most brain cancers start elsewhere in the body, but one particularly aggressive and uncommon form—glioblastoma—originates in the brain itself.

Recommended for you

Researchers discover key signaling protein for muscle growth

November 20, 2017
Researchers at the University of Louisville have discovered the importance of a well-known protein, myeloid differentiation primary response gene 88 (MyD88), in the development and regeneration of muscles. Ashok Kumar, Ph.D., ...

New breast cell types discovered by multidisciplinary research team

November 20, 2017
A joint effort by breast cancer researchers and bioinformaticians has provided new insights into the molecular changes that drive breast development.

Brain cell advance brings hope for Creutzfeldt-Jakob disease

November 20, 2017
Scientists have developed a new system to study Creutzfeldt-Jakob disease in the laboratory, paving the way for research to find treatments for the fatal brain disorder.

Hibernating ground squirrels provide clues to new stroke treatments

November 17, 2017
In the fight against brain damage caused by stroke, researchers have turned to an unlikely source of inspiration: hibernating ground squirrels.

Molecular guardian defends cells, organs against excess cholesterol

November 16, 2017
A team of researchers at the Harvard T. H. Chan School of Public Health has illuminated a critical player in cholesterol metabolism that acts as a molecular guardian in cells to help maintain cholesterol levels within a safe, ...

Prototype ear plug sensor could improve monitoring of vital signs

November 16, 2017
Scientists have developed a sensor that fits in the ear, with the aim of monitoring the heart, brain and lungs functions for health and fitness.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.