[Sportsandrec] Spatial Development

[Jody Ianuzzi]

This is interesting:

Researchers uncover new understanding of brain's early spatial development.

10 January 2013.

Researchers from our Department of Psychology have uncovered a new
understanding of how the brain develops its sense of space by working with
blind people.

The researchers found that people who lose their sight later in life use a
different method of following directions to those who are born without
sight.

This means that the brain needs to have a visual experience early on in life
in order to build a visual perspective, or frame of reference, to know what
is where.

The researchers carried out a study with participants including those who
were congenitally blind; those who became blind later in life; and others
who were sighted, to learn which methods the different groups used to
remember where things are.

The study revealed that people who have been sighted and then become blind
use an 'allocentric' reference frame, meaning they remember locations as
they are positioned relative to one another, and this is the same as sighted
people who do this task, even when blindfolded.

In contrast congenitally blind participants preferred an 'egocentric'
reference
frame meaning they first remember a starting point at home and then store a
memory of the locations from the home location.

Dr Michael Proulx who led the study said the results help us to understand
more about the role of a critical period for developmental vision on spatial
cognition and brain organisation.

He said: "In our study we were curious as to whether having visual
experience during child development was key to creating the structures in
the brain to support such an allocentric reference frame. First we found an
interesting difference between the congenitally blind and sighted people:
although the sighted people preferred the allocentric, reference frame, the
congenitally blind participants preferred the self-centred or egocentric
reference frame for remembering locations.

"The important piece of the puzzle, however, was whether the late blind
people would perform like the congenitally blind, showing that current
visual experience matters, or like the sighted, showing the role of early
visual experience. The results were clear: the late blind performed the same
as the sighted participants. Therefore having the experience of vision early
in life lays the groundwork in the brain for the representation of locations
in a different reference frame than that found in people who never had
visual experience."

All of the participants of the study were blindfolded and then walked to the
locations of objects in a large room. They were later tested on a computer
with a virtual pointing task that asked them to remember objects in the room
relative to the other object locations.

Dr Proulx and his colleagues are following up this finding with additional
research to investigate how additional information, such as the texture or
sound of the environment, might influence the frame of reference used.

This would allow for improved maps rendered in Braille or sound to be
produced for visually impaired persons to use in public places, such as rail
stations, or in new cities.

They are also examining the impact of visual experience on the neural basis
for spatial learning and memory by examining how the congenitally blind and
late blind brains represent spatial information in the absence of vision.

The full paper, Visual experience facilitates allocentric spatial
representation is published in the journal Behavioural Brain Research.

Source URL:
http://www.bath.ac.uk/news/2013/01/10/spatialdevelopment/