The hippocampus in the brain’s temporal lobe is not only responsible for long-term memory, but also involved in quick and successful conflict resolution, researchers have found.
In their everyday life, people are constantly confronted with decision conflicts, especially if they need to suppress an action that would have made sense under normal circumstances.
For example: when the pedestrian lights go green, a pedestrian would normally start walking. If, however, a car comes speeding along at the same time, the pedestrian should stay where he is.
In their experiment, researchers headed by Dr Nikolai Axmacher from the Ruhr-Universitat Bochum (RUB) in Germany, together with colleagues from the University Hospital of Bonn as well as in Aachen and Birmingham opted for a less threatening situation.
Test participants heard the words “high” or “low” spoken in a high or low tone, and they had to state – regardless of the meaning of the word – at what pitch the speaker said them.
If the pitch doesn’t correspond with the meaning of the word, a conflict is generated: the participants would answer more slowly and make more mistakes.
The team demonstrated with two different measurement methods that the hippocampus is active in such conflicting situations; this applies particularly when a person solves the conflicts quickly and successfully.
Axmacher and colleagues analysed the brain activity in healthy participants with functional magnetic resonance imaging.
They gained the same results in epilepsy patients who had EEG electrodes implanted in the hippocampus for the purpose of surgery planning; this is how the researchers could measure the activity in that brain region directly.
Because the hippocampus is essential for memory, the researchers speculate about its role in conflict resolution.
“Our data show first of all a completely new function of the Hippocampus – processing of activity conflicts,” said Carina Oehrn from the Department of Epileptology at the University Hospital of Bonn.
“However, in order to answer the question how that function interacts with memory processes, we will have to carry out additional tests,” said Oehrn.
“Perhaps the memory system becomes particularly active if a conflict has been successfully resolved,” said Axmacher.
The study was published in the journal Current Biology.