Swedish researchers have constructed a mathematical activity model of the brain’s frontal and parietal parts, to increase the understanding of the capacity of the working memory and of how the billions of neurons in the brain interact.

One of the findings they have made with this “model brain” is a mechanism in the brain’s neuronal network that restricts the number of items we can normally store in our working memories at any one time to around two to seven.

The study, which is published in the journal PNAS, is based on a multidisciplinary project co-run by two research teams led by professors Torkel Klingberg and Jesper Tegnér.

For their project, the researchers used techniques from different scientific fields, applying them to previously known data on how nerve cells and their synapses function biochemically and electrophysiologically.

They then developed, using mathematical tools, a form of virtual or computer simulated model brain.

The computations carried out with this “model brain” were tested using fMRI experiments, which allowed the researchers to confirm that the computations genuinely gave answers to the questions they asked.

“It’s like a computer program for aircraft designers,” says Fredrik Edin, Ph.D in computational neuroscience. “Before testing the design for real, you feed in data on material and aerodynamics and so on to get an idea of how the plan’s going to fly.”

“The model predicts, for instance, that increased activation of the frontal lobes will improve working memory,” continues Dr Edin.

“This finding was also replicable in follow-up fMRI experiments on humans. Working memory is a bottleneck for the human brain’s capacity to process information. These results give us fresh insight into what the bottleneck consists of.”

Source: Karolinska Institutet