Switchboard in the brain helps us learn and remember at the same time

Jan 13, 2009

The healthy brain is in a constant struggle between learning new experiences and remembering old experiences, a new study in this week's PLoS Biology reports. Virtually all social interactions require the rapid exchange of new and old information. For instance, normal conversation requires that while listening to the new information another person is providing, we are already retrieving information in preparation of an appropriate reply. Yet, some memory theories assume that these different modes of memory cannot happen at the same time and compete for priority within our brain.

Brain researchers now provide the first clear evidence supporting a competition between learning and remembering. Their findings also suggest that one brain region can resolve the conflict by improving the rapid switch between learning and remembering. The researchers included Willem Huijbers, Cyriel Pennartz, and Sander Daselaar of the Netherlands' University of Amsterdam, and Roberto Cabeza of Duke University.

The researchers used a novel memory task that forced learning and remembering to occur within a brief period of time. In the study, a group of adults in their 20's looked at a set of regular words presented in the middle of a screen. Participants rapidly tried to remember whether the words had previously been studied or not. Simultaneously, a set of colorful pictures were presented in the background. Meanwhile, the participants' brains were scanned with functional magnetic resonance imaging (fMRI). After brain scanning, participants were surprised with another memory test including the colorful background pictures instead of the words.

In support of a memory competition, the surprise test showed that learning the pictures is much more difficult when simultaneously remembering a word. At the same time, learning the pictures becomes easier when a word is forgotten. The brain scans revealed that the brain areas involved in learning of the pictures were also less activated when words were simultaneously remembered. In other words, the process of remembering appears to suppress the brain regions involved in learning, the authors note.

The researchers also found one region in the left frontal part of the brain that was only active when both learning and remembering succeeded. Interestingly, activity in this region was specific to those participants that showed minimal suppression of learning activity. In other words, whether they simultaneously remembered a word or not, it did not influence their brain activity during the learning of the background pictures.

vThis frontal region could function as a switchboard in the brain, the researchers suggest. As learning and remembering cannot happen at the same time, this region might help us to rapidly switch the state of our brain between "learn" and "remember" modes.

It was already thought from patient studies that this frontal region is important for rapid switching between tasks and rules. Patients with damage to this area have problems in rapidly adapting to new situations and tend to persevere in old rules. The same region is also affected in older adults.

Future research should reveal the extent and practical implications of impairments in switching between learning and remembering in patients and older adults, and whether we can improve our switchboard through training.

Citation: Huijbers W, Pennartz CM, Cabeza R, Daselaar SM (2009) When learning and remembering compete: A functional MRI study. PLoS Biol 7(1): e1000011. doi:10.1371/ journal.pbio.1000011
biology.plosjournals.org/perls… journal.pbio.1000011

Source: Public Library of Science

Explore further: Endangered Santa Catalina Island fox population nearing full recovery

add to favorites email to friend print save as pdf

Related Stories

We must defend science if we want a prosperous future

Mar 03, 2015

Today's Australians are, by far, the best educated cohort in our history –- on paper, anyway -– but this is not reflected in the quality of our political discourse. We appear to be lacking in courage, ...

Evolving robot brains

Mar 02, 2015

Researchers are using the principles of Darwinian evolution to develop robot brains that can navigate mazes, identify and catch falling objects, and work as a group to determine in which order they should ...

Intermediary neuron acts as synaptic cloaking device

Feb 26, 2015

Neuroscientists believe that the connectome, a map of each and every connection between the millions of neurons in the brain, will provide a blueprint that will allow them to link brain anatomy to brain function. ...

Bumblebees make false memories too

Feb 26, 2015

It's well known that our human memory can fail us. People can be forgetful, and they can sometimes also "remember" things incorrectly, with devastating consequences in the classroom, courtroom, and other ...

Recommended for you

Scientists unlock tangled mysteries of DNA

2 hours ago

Chromosomal proteins hold the key to our DNA and they are changing, according to Jose Eirin-Lopez, marine sciences professor in the Florida International University Department of Biological Sciences.

Ferns may hold key to land rehabilitation

3 hours ago

Ferns may have potential in rehabilitating land following work by WA researchers who investigated how ferns are able to survive in semi-arid environments of Australia.

Moves to automate identification of Saimaa ringed seals

3 hours ago

Moves are being made to automate the identification of Saimaa ringed seals. This would bring new kinds of real-time information on how the extremely endangered species behaves, the movements of individual seals, and what ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.