Past Experiences Helps Human Brain Understand Present Experiences
Researchers at University of
Oxford, UCL and Deepmind have found that past experiences can play a vital role
in understanding and determining our approach to new experiences.
It is thought that making these inferences relies on the models of the world that we create in our mind during everyday experiences, which use the same neural mechanisms (and brain cells) that help us understand our position relative to other objects and places.
Although predominantly encoding our current location, these brain cells also spontaneously recall old memories, and explore new possibilities – a phenomenon known as “replay”.
The researchers trained participants in a task defining an ordering of everyday objects, and then presented a new set of familiar objects in a scrambled order - during which they applied MEG neuroimaging to map brain activity in the participants.
They observed that representations of the new objects were reactivated during subsequent rest. These 'replay' events occurred much faster than in their actual experience.
Human replay occurs while the brain is resting between exercises, and reverses direction after a reward has been given for making the correct choice.
They also showed that human replay spontaneously reorganises experience based on learnt structure. This enables us to spontaneously re-order sequences to integrate past knowledge with current experiences.
Professor Timothy Behrens of Oxford’s Nuffield Department of Clinical Neurosciences, who was involved in the research, said: ‘Replay plays out events in a different order to the order they were seen in, which is a sophisticated jump for the brain to make.
‘A defining feature of human intelligence is the ability to make strong inferences on the basis of sparse observations. If you notice your husband’s wallet on the kitchen table, you immediately know he is more likely to be in the garden than the pub. It is completely unknown how such inferences are performed in our brains, but our research suggests an important role for replay.
For more details: http://www.ox.ac.uk/news/2019-07-04-human-brains-reorganise-experiences-while-resting-find-new-solutions