Saturday, March 5, 2011

Genetically engineered brain virus can boost your memory

 Need to cram for a big test? Trying to learn a new language? Just had a great vacation? Scientists have developed a procedure that may be able to help you remember things, as long as you're willing to inject a genetically engineered virus directly into your brain.
Remember how scientists can now selectively erase scary memories? As it turns out, chemical memory modification works both ways, and you can also use it to make memories last longer, at least in rats.
There's one specific enzyme in your brain, called protein kinase M ζ, that seems to control how well memories are preserved. A few years ago, scientists showed that inhibiting the enzyme caused memories to fade much more rapidly than normal, and they've just published a paper showing that it works the other way, too: making more of the enzyme causes memories to stick around longer than they would normally, even after they've already been created.
While it's suggested that this research could lead to memory-enhancing drugs, so far all the testing has just been done on rats and only on very specific types of associative memories. Oh, and there's also the fact that getting more protein kinase M  isn't like taking a pill, but instead involves custom-making a virus to pump out the enzyme and then infecting specific parts of the brain with it using what may or may not be a giant needle.
Still, we're just in the first stages of this research, and it seems pretty promising. And honestly, if someone said 'just let me shove this needle into your ear and inject your brain with a friendly little virus and then you'll have a perfect memory,' I'd probably let them do it, wouldn't you?

Learning behind movement studied

The research looked at brain chemistry, not bad dancing

A brain chemical called GABA is the reason why “some people dance like Fred Astaire – while others have the natural rhythm of Ann Widdecombe”, the Daily Mail has reported.
The news is based on a study involving 12 healthy young adults that had their brains stimulated with  electrodes to alter levels of GABA, one of the main chemicals regulating the transmission of electrical impulses in the brain. The subjects’ brain activity and reaction speed were then tested while they learned a task involving pressing buttons in response to visual cues, with the researchers looking at how performance related to normal and altered GABA levels.
Though of scientific interest, this experimental scenario was carried out in very few people and has only limited direct implications. The study only assessed each individual’s ability in one test of time reaction, and the results cannot be applied to other types of movement, including dance. The findings also require replication in much larger numbers of people, with different tests of movement, before GABA can be considered to be responsible for our capacity to learn movement.

Where did the story come from?

The study was carried out by researchers from the Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), at the University of Oxford, and was funded by the Wellcome Trust and the National Institute for Health Research Biomedical Research Centre, Oxford. The study was published in the peer-reviewed scientific journal Current Biology.


What kind of research was this?

This was a laboratory study that aimed to investigate the role a brain chemical called GABA plays in the learning of movement. GABA (γ-aminobutyric acid) is one of the main chemicals involved in regulating the transmission of electrical impulses through the nervous system, and also has a direct effect upon muscle tone. Its main overall effect is in muscle relaxation. The researchers theorised that variation between people in the responsiveness of their GABA system could influence their capacity to learn new movements, and they wanted to test the theory.
The news has greatly oversimplified this scientific laboratory study, which used artificial methods to alter levels of GABA and assess how this affected learned finger movements. The study had nothing to do with dancing. The study, though enhancing our understanding of nervous activity and chemical transmission, does not provide a complete explanation of GABA’s role in learning movement.

What did the research involve?

The research involved a technique known as transcranial direct current stimulation (tDCS), which is known to decrease GABA, thus increasing nerve transmission and enhancing short-term learning. tDCS is performed by running a small current across two electrodes, one placed over the right side of the head and one over the left. The authors say that they used tDCS due to time constraints, as prolonged periods performing complex visual-motor tasks are required to alter GABA levels naturally, and their study could not allow for this. They anticipated that individuals with lower levels of GABA due to tDCS would demonstrate less activity in motor areas of the brain when learning new movements, and also demonstrate less behavioural evidence of learning.
The researchers recruited 12 healthy young adults (average age 23) who took part in three testing sessions on different days. In the first two sessions, 10 minutes of tDCS were delivered to the brain with the activity of brain chemicals measured before and after using a scanning technique known as magnetic resonance spectroscopy (MRS). In particular, the researchers were interested in activity in the areas of the brain controlling hand movements and vision. The researchers assessed brain metabolic activity and obtained a 15-minute spectrum of GABA activity prior to stimulation and in the 20 minutes immediately after stimulation.
Session three did not involve tDCS. Participants performed a task of visually-cued reaction time while brain images were taken. The task involved participants trying to learn a pattern of button pressing on a small keypad using just four fingers. While performing the tasks functional magnetic resonance imaging (fMRI) was taken. fMRI is a special type of MRI brain scan that allows measurement of activity of the nervous system. It does this through observing changes in blood flow.  They then repeated transcranial stimulation to reduce the GABA in their brains by applying a small current, as in session one, and asked participants to repeat the sequencing task while they re-assessed their brain activity using fMRI.

What were the basic results?

In session three the researchers noted variation in motor learning ability across the 12 individuals, although, generally, as the number sequences got harder, reaction times decreased in all participants. MRS showed a correlation between mean reaction time during the sequencing tests and the baseline levels of GABA (GABA levels before tDCS was performed), with those with higher GABA levels having slower reaction times.
As expected, GABA release decreased following tDCS, but the degree of decrease varied and correlated with the person’s reaction times and their level of brain nervous activity (people with better reaction times showed greater decrease in GABA levels).
How did the researchers interpret the results?
The authors conclude that the responsiveness of the GABA system in the individual could have an effect upon the short-term ability of a person to learn new movements.

Conclusion

This research is of scientific interest, and demonstrates the responsiveness of chemical transmitters in the central nervous system when undergoing direct stimulation. It also examines how this relates to a person’s capacity to learn a new motor activity.
However, this experimental scenario in 12 people has limited direct implications. The study only assessed each individual’s ability in one test of time reaction, and the results cannot be applied to all other areas of movement, such as dance. Also, it is not possible to attribute all the effect to GABA; other chemical transmitters could be involved. As the authors acknowledge, it may be that their measure of GABA is a surrogate marker for other chemical changes that are taking place and having a direct effect. The findings would require replication in much larger numbers of people, with different tests of movement, before the theory that GABA is responsible for our capacity to learn movement could be confirmed.

Criminal Minds Are Different on Brain Scans


The brains of certain criminals aren't the same as those of the rest of the population, reveals recent neuroscience research. In a study of 21 people with antisocial personality disorder, the brain scans of antisocial people were compared with a control group of people without mental disorders, reports MSNBC. The research showed that people with antisocial personality disorder had an 18 percent reduction in volume in the brain's middle frontal gyrus, as well as a 9 percent reduction in volume in the orbital frontal gyrus. Both sections with decreased volume are in the brain's frontal lobe. Antisocial personality disorder is often present in many convicted criminals who break the law and have little regard for the rights of others.

Working of brain depends on your genes--study

Do you think slow? Don’t blame yourself. Blame your genes, claim scientists.
A latest study has found that the genes inherited by parents play a pivotal role in brain-related illnesses in the child.
Dr. Alex Fornito and his colleagues from the Melbourne Neuropsychiatry Centre at the University of Melbourne, Australia, University of Queensland and Cambridge University in the United Kingdom initiated the first-of-its-kind study that links working of the brain with genes.
"The brain is an extraordinarily complex network of billions of nerve cells interconnected by trillions of fibres. In this network, efficient communication is very important. More connections make the network more efficient, allowing different parts of the brain to talk to each other quickly and effectively,” said the lead investigator.
Study examines brain scans of twins
For the study, the researchers examined the brain scans of 38 identical twins and 26 non-identical twins.
While identical twins have all genes common, non-identical ones have only half of their genes the same.
"Given this difference, if genes are important in determining a trait then we would expect the identical twins to be a lot more similar than the non-identical twins. So we can use various statistical models to work out the exact contribution the genes make to the trait,” said Dr. Alex.
The researchers calculated the cost-efficiency of the network wiring of the brain, using MRI scans and found that cost-efficiency of the brains varied from one human to another and almost 60 percent of these differences could be traced in genes.
Also, the genes played most important role in strategic thinking, planning, and memory, which is why slow brain is something one is born with.
Importance of study
The findings of the study will help in understanding the working of the brain and in hence help cure the mental illnesses.
"Ultimately, this research may help us uncover which specific genes are important in explaining differences in cognitive abilities, risk for mental illness and neurological diseases such as schizophrenia and Alzheimer's disease,” said the lead author.
“Although genes play a major role, the environment and other factors can influence the timing of when things go wrong in cases of mental illness and other brain disorders,” concluded the researchers.