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: Memory loss from West Nile virus may be preventable

Related Stories

Memory loss from West Nile virus may be preventable

January 15, 2018
More than 10,000 people in the United States are living with memory loss and other persistent neurological problems that occur after West Nile virus infects the brain.

Neuroscientists suggest a model for how we gain volitional control of what we hold in our minds

January 16, 2018
Working memory is a sort of "mental sketchpad" that allows you to accomplish everyday tasks such as calling in your hungry family's takeout order and finding the bathroom you were just told "will be the third door on the ...

Smart insulin patch may aid future therapies

January 18, 2018
A smart insulin patch, once translated for humans, could eliminate the need for constant blood testing and help diabetics maintain a more consistent level of blood glucose.

Revealing snapshots: Advanced imaging uncovers how the brain responds to vascular injury

January 2, 2018
Pericytes, a little-understood type of cell on the brain's blood vessels, grow into the empty space left when neighboring pericytes die, report researchers at the Medical University of South Carolina (MUSC) in a January 2nd, ...

Physicists negate century-old assumption regarding neurons and brain activity

December 21, 2017
Neurons are the basic computational building blocks that compose our brain. Their number is approximately one Tera (trillion), similar to Tera-bits in midsize hard discs. According to the neuronal computational scheme, which ...

Why a drug treatment for dementia eludes researchers

January 11, 2018
Finding a cure for neurodegenerative diseases such as Alzheimer's is challenging. They're difficult to diagnose, and drugs struggle to get into the brain as the brain's blood supply is largely separate to the rest of the ...

Recommended for you

Bioengineered soft microfibers improve T-cell production

January 18, 2018
T cells play a key role in the body's immune response against pathogens. As a new class of therapeutic approaches, T cells are being harnessed to fight cancer, promising more precise, longer-lasting mitigation than traditional, ...

Weight flux alters molecular profile, study finds

January 17, 2018
The human body undergoes dramatic changes during even short periods of weight gain and loss, according to a study led by researchers at the Stanford University School of Medicine.

Secrets of longevity protein revealed in new study

January 17, 2018
Named after the Greek goddess who spun the thread of life, Klotho proteins play an important role in the regulation of longevity and metabolism. In a recent Yale-led study, researchers revealed the three-dimensional structure ...

The HLF gene protects blood stem cells by maintaining them in a resting state

January 17, 2018
The HLF gene is necessary for maintaining blood stem cells in a resting state, which is crucial for ensuring normal blood production. This has been shown by a new research study from Lund University in Sweden published in ...

Magnetically applied MicroRNAs could one day help relieve constipation

January 17, 2018
Constipation is an underestimated and debilitating medical issue related to the opioid epidemic. As a growing concern, researchers look to new tools to help patients with this side effect of opioid use and aging.

Researchers devise decoy molecule to block pain where it starts

January 16, 2018
For anyone who has accidentally injured themselves, Dr. Zachary Campbell not only sympathizes, he's developing new ways to blunt pain.

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.