A little practice goes a long way for the brain

A little practice goes a long way, according to researchers at McMaster University, who
have found the effects of practice on the brain have remarkable staying power.

The study, published this month in the journal Psychological Science, found that when
participants were shown visual patterns – faces, which are highly familiar objects, and
abstract patterns, which are much less frequently encountered – they were able to retain
very specific information about those patterns one to two years later.

We found that this type of learning, called perceptual learning, was very precise and
long-lasting, says Zahra Hussain, lead author of the study who is a former McMaster
graduate student in the Department of Psychology, Neuroscience & Behaviour and now a
Research Fellow at the University of Nottingham. These long-lasting effects arose out
of relatively brief experience with the patterns  about two hours, followed by nothing
for several months, or years.

Over the course of two consecutive days, participants were asked to identify a specific
face or pattern from a larger group of images. The task was challenging because images
were degradedfaces were cropped, for exampleand shown very briefly. Participants
had difficulty identifying the correct images in the early stages, but accuracy rates
steadily climbed with practice.

About one year later, a group of participants were called back and their performance on
the task was re-measured, both with the same set of items theyd been exposed to
earlier, and with a new set from the same class of images. Researchers found that when
they showed participants the original images, accuracy rates were high. When they
showed participants new images, accuracy rates plummeted, even though the new
images closely resembled the learned ones, and they hadnt seen the original images for
at least a year.

During those months in between visits to our lab, our participants would have seen
thousands of faces, and yet somehow maintained information about precisely which
faces they had seen over a year ago, says Allison Sekuler, co-author of the study and
professor and Canada Research Chair in Cognitive Neuroscience in the Department of
Psychology, Neuroscience & Behaviour. The brain really seems to hold onto specific
information, which provides great promise for the development of brain training, but
also raises questions about what happens as a function of development. How much
information do we store as we grow older and how does the type of information we
store change across our lifetimes? And what is the impact of storing all that potentially
irrelevant information on our ability to learn and remember more relevant information?

She and her colleagues point to children today who are growing up in a world in which
they are bombarded with sensory information, and wonders what will happen.

We dont yet know the long-term implications of retaining all this information, which is
why it is so important to understand the physiological underpinnings, says Patrick
Bennett, co-author and professor and Canada Research Chair in Vision Science in the
Department of Psychology, Neuroscience & Behaviour. This result warrants further
study on how we can optimize our ability to train the brain to preserve what would be
considered the most valuable information.

The research was funded by the Natural Sciences and Engineering Research Council
(NSERC) and the Canada Research Chair program.