A new study carried out by MIT neuroscientists found that people can improve their attention span by way of managing their own alpha brain waves when performing certain tasks. The research demonstrated that once people were able to suppress the alpha waves in one side of the parietal cortex their attention span was better regarding objects located on the opposite side of their visual field.
This research is the first of its kind as it demonstrates a cause-and-effect relationship never seen before – one that suggests we can improve our attention through neurofeedback. Using neurofeedback is a non-invasive way of monitoring and controlling brain activity under different circumstances. While it’s still not clear how long these effects might last it does show promise in the potential to help those suffering from either lack of attention or some other kind of neurological condition.
Alpha waves have a brain wave frequency of around 8 to 12 hertz and are thought to be involved in the filtering of distracting sensory information. Previous research in both humans and animals, has revealed a strong relationship between alpha brain waves and attention. However, researchers are still unsure if alpha waves are responsible for controlling attention or are simply a byproduct of something else that regulates attention.
To test this theory, the researchers devised an experiment where subjects were asked to complete a task real-time feedback on their alpha waves was relayed. They had to look in the center of a screen where a grating pattern was displayed and use mental effort to make the pattern more visible by increasing the contrast of it. As the subjects did this, researchers measured their alpha levels using magnetoencephalography (MEG). Alpha levels from both the right and left hemispheres of the parietal cortex were measured in order to calculate the asymmetry between them.
The experiment showed that the more asymmetry between the two hemispheres increased, the more visible the grating pattern. While subjects were not consciously aware of the way in which they were controlling their brain waves, they still managed to do it. And this success could clearly be seen by enhanced attention on the other side of the visual field. While subjects looked at the pattern on the screen, dots of light were flashed either side. Even though they were told to ignore these, researchers measured how each participant’s visual cortex reacted to them.
Half of the subjects were trained to suppress the left side of the brain’s alpha waves, while the other half learned to suppress the right side. Those with reduced alpha waves in the left hemisphere exhibited a larger response in their visual cortex when shown flashes of light on the right-hand side of the screen, while the opposite effect was seen in those with reduced alpha waves in the right hemisphere. “Alpha manipulation really was controlling people’s attention, even though they didn’t have any clear understanding of how they were doing it,” says director of MIT’s McGovern Institute for Brain Research and senior author of the paper, Robert Desimone.
On completion of the neurofeedback training session, subjects were asked to carry out two further tasks that involved attention. One test involved the subject performing a similar experiment to that previously where they stared at a pattern on a screen. Some were told to look in a certain direction while others were not given any direction. Those that were given clear instructions to look one way, mostly looked that way. Those that had no instruction tended to look more to the side favored during the neurofeedback training.
The second test involved the subjects looking at an outdoor scene or some other kind of computer-generated image. In tracking their eye movements, the researchers found most people drawn towards the side their alpha waves were trained to pay attention to previously.
So, it seems, results from both of those tests showed that enhanced attention continued. However, further research is needed to determine how long those effects may last.