One of the things that put us, as humans, at the top of the food chain is the fact that we’ve evolved substantially enough to be able to take control of our own thoughts. But, the big question is, how do we do it?
To try and answer that age-old question, MIT neuroscientist Earl Miller along with co-authors Mikael Lundqvist and Andre Bastos presented a new working memory model in the 30th-anniversary edition of Neuron that explains all about how the brain holds information and how it has control over that information.
The way in which the brain operates its working memory is depicted in the model. It shows how waves in the low alpha and beta frequencies contain our goals and knowledge as well as helping to regulate the higher frequency gamma rays. In addition to that, it shows how the temporary storage of that information is achieved through the help of synapses.
There are two fundamental beliefs challenged by the model. The first is that brainwaves don’t have any functional meaning and are simply byproducts of brain activity. The second is that the working memory is made up of a constant hum of neural firing, opposed to short, sharp bursts. But the newer model shows otherwise.
Firstly, it shows what effect different wave frequencies have on brain function. During the study, the animals were trained to play a game to show how well they recognized patterns. They were all shown a series of images and had to try and judge the sequence of the next two images.
Upon recording brain activity, the researchers found a distinct pattern of interplay between the beta and gamma wave frequencies. In this instance, beta levels increased when taking in information or reading it out, while gamma levels declined when this information was no longer needed. More amazingly, the researchers saw how deviations from these patterns strongly corresponded to the animals making mistakes. “This adds to the mounting evidence that brain waves have a major functional role in the brain,” says Miller.
The paper provides a good foundation in which for other researchers to follow when studying working memory. “While many aspects of this theory need to be linked more closely to behavior, Miller’s account provided a roadmap for the future of the working memory field,” says Sabine Kastner, professor of psychology and neuroscience at Princeton University. The next move for Miller and the team is to explore more deeply the finer points of working memory and to try and find ways to enhance it when it comes to those suffering from psychiatric diseases.