Flexibility of the brain is important for learning new things

Individual nerve cells in our brains create new associations within minutes. This appears from research by the Netherlands Institute for Neuroscience and VUmc, published in the scientific journal Nature Communications. This discovery offers new insights in how the brain adapts itself, which could help to promote recovery in people with brain damage sustained due to, for instance, an accident, an infarction or a brain tumor.

The researchers studied the way in which the activity of individual nerve cells in the human temporal lobe changes when you are learning something new. The temporal lobe is a brain region where new associations are stored. It turned out that it takes only a few minutes before individual nerve cells in the brain create new associations.

Electrodes in the brain

The activity was measured by means of electrodes in the brains of VUmc patients with epilepsy who did not respond well to medication. This is why it was examined in these patients whether it might be possible to eliminate the epileptic ‘focus.’ One way of determining which part of the brain or the tumor must be removed by the neurosurgeon, is to place electrodes in the head of these patients. For this particular project, extra electrodes were placed to carry out measurements of the function of memory, to be used by, among others, the scientists of the Netherlands Institute for Neuroscience and the VUmc Hersentumorcentrum (which specializes in brain tumors), both in Amsterdam.

Wendy van Dijk

For this project, patients learned the order of a series of photographs by heart. In this series a photograph of Dutch celebrity Wendy van Dijk was followed by that of one of the patients’ family members. This series of photographs was repeated until the patients knew the exact order. Results show that when the picture of Wendy van Dijk predicted that the next picture would be a picture of a family member, for instance a brother, the ‘brother’ cells were already activated even before the actual picture of the brother was shown. This happened after only 11 repetitions of the series of photographs. These results show how quickly these nerve cells store new information: within a few minutes.

Publication

Reddy, L. et al . Learning of anticipatory responses in single neurons of the human medial temporal lobe. Nat. Commun. 6:8556 doi: 10.1038/ncomms9556 (2015).