麻豆传媒

STUDYING for an exam? Begin by thinking your way into a learning state.

Until now, neuroscientists have focused on identifying parts of the brain that are active during learning. 鈥淏ut no one has looked at the preparedness state,鈥� says at the Massachusetts Institute of Technology. 鈥淭he idea is to identify before the event whether the brain is prepared to be a learner.鈥�

Gabrieli and his colleagues used functional MRI scanning to monitor the naturally fluctuating brain activity of 20 volunteers and investigate whether the brain enters such a learning state. While in the scanner, each person was presented with 250 images, one at a time, and asked to memorise them. The volunteers were shown the images again 2 hours later 鈥� mixed in with 250 new ones 鈥� and asked to remember which they had seen before.

Looking through the results, the team was surprised to find that in the moments before individuals were shown images that they later remembered, they had low levels of activity in the parahippocampal place area 鈥� a region of the brain that is known to be highly active during learning. 鈥淢aybe the fact that this region was less active meant that the deck was cleared 鈥� that it was more open for a stimulus to provoke a response,鈥� suggests Gabrieli.

To investigate further, the team attempted to boost subsequent participants鈥� memory test scores by presenting them with images only when they showed this pattern of brain activity. 鈥淭here was around a 30 per cent improvement in the memory task,鈥� Gabrieli says (NeuroImage, ).

The MIT team is now working on a way to monitor this 鈥減reparedness to learn鈥� using electroencephalography (EEG) 鈥� a more portable and much cheaper brain-monitoring technique. Gabrieli鈥檚 idea is to make learning more efficient by selectively teaching the prepared brain. 鈥淵ou could imagine a computer-based learning system which would stop when the brain is not prepared to learn and restart when it is,鈥� he says.

聯A computer-based learning system could stop when the brain isn鈥檛 prepared to learn and restart when it is聰

, at the US National Institutes of Health in Bethesda, Maryland, who was not involved in the study, thinks the next step should instead be to use the existing scanning method to train individuals to enter good brain states of their own accord, by rewarding them when they do. 鈥淥ptimising these brain regions would provide a more sophisticated way of approaching a learning task,鈥� says Cohen. 鈥淚t鈥檚 a very exciting idea.鈥�

A third approach would be to find a way of stimulating the same pattern in a person鈥檚 brain. It has already been shown that brain stimulation using electric currents can boost a number of cognitive functions (see 鈥淎pply the electrodes鈥︹��). Could it help make us better learners, too?

鈥淐ombining brain stimulation with Gabrieli鈥檚 approach could take performance to the next level,鈥� says Cohen. He suggests training an individual once they have entered the preparedness state, and then stimulating areas of the brain known to be involved in memory consolidation to cement the learning process: perhaps the ultimate in brain optimisation.