Because
of the several med school interviews I was anticipating, I was trying to
reflect more on all sorts of random things. True enough, one hypothetical
question that was asked concerned becoming paralyzed from the neck down and my
corresponding reaction to that predicament. Being the physically active person I
am, I would obviously be devastated if I were to lose my ability to move around
from place to place using my own two feet and to play around and tinker with
things using my hands and fingers. After this, I thought about which of the
five senses I would be most unable to live without. The popular choice of the
most difficult sense to live without is the sense of sight. It must definitely
be really hard to imagine living in constant darkness, unable to see the
richness of the world. Apart from that, vision is often needed to perform basic
tasks with a certain amount of precision. I may need glasses and contact lenses
to help correct my slightly impaired vision, but it is a compromise I am
willing to make in order to enjoy all the visual pleasures out there.
Most
people know of bats that are practically blind, being able to compensate for
their poor vision by using a technique called echolocation (Stroffregen &
Pittenger, 1995). Similarly, dolphins usually rely on their built in sonar
systems to navigate the underwater terrain. These examples present two
contrasting examples are demonstrations of the application of the ability to
use echoes to analyze the features of a certain scene. Bats rely heavily on
this ability to navigate while flying, and dolphins may use this to supplement the
visual stimuli they receive or resort to when there is a lack of visual
information.
Robin: "Batman, better leave the driving to me next time."
With
this being the case, being without sight isn’t all that bad, after all. In a recently
published 2011 study, researchers found evidence for sighted people being able
to quickly learn how to interpret auditory information contained in echoes to allow
for size and position discrimination in a given scene. They performed two
separate experiments, each of which was used to assess the level of the echolocation
ability of the participants. One result was that the size discrimination threshold
was relatively constant with increasing distances. This is because the size of
the angle, rather than distance, is what mainly determines the ability for size
discrimination. The other experiment used a novel vernier stimulus presented to
the participants to measure the spatial resolution of their echolocation
ability. It was shown that training can produce improvements in the proficiency
of sighted people in the use of echolocation. These improvements ranged from
gaining a crude ability to echolocate, to nearly approximating the skill level
of a blind individual in using echolocation.
Going
back to my reflection on what sense I cannot live without the most, perhaps I would
still stick with the sense of sight (however, I have also read about a compelling
argument that the sense of hearing is a more indispensable sense modality).
Although I am hoping that I won’t have to rely on it full-time out of
necessity, learning how to use echolocation to navigate through a scene and to
be able to discriminate between the objects present in it is a skill that I would
definitely want to learn. Aside from the practical applications, I think it can
actually be quite fun too to be able to do things in the dark. ;)
Paper beats rock!
Teng, S., & Whitney, D. (2011). The acuity of echolocation: Spatial
resolution in sighted persons compared to the performance of an expert who is
blind. Journal of Visual Impairment
& Blindness, 105(1), 20-32.
Stroffregen, T.A., & Pittenger, J.B.
(1995). Human echolocation as a
basic form of perception and action. Ecological Psychology, 7(3), 181-216.
Images from:
http://www.flickr.com (Allard62)
http://www.fanpop.com
No comments:
Post a Comment