Thursday, June 22, 2023

Don't Walk Into The Wall!

    Karl Dallenbach conducted an experiment in the 1940s where two blind men and two sighted men were asked to put on blindfolds and walk toward a large board and stop before running into it, which they were able to do multiple times without running into the board. When asked how they were able to do it, they said that they could feel the pressure on their face of the board getting closer. However, when they were asked to complete the same task on carpet, with no shoes on, and headphones that emitted a loud tone, they walked into the board every time. This shows how the gentlemen were using reflected sounds from their shoes hitting against the hard floor to measure how close to the board they were.

    I tested this out myself as well to see just how well I would do. I walked toward a wall with shoes on and blindfolded and would stop just before hitting it every time. My room is carpeted so I tried again with socks on and headphones playing loud music. I walked right into the wall! I was so shocked to have hit the wall because just like the gentlemen in the experiment, I thought I could feel the pressure on my face preventing me from walking into the wall. My little experiment just proved we use reflected sound to help us not walk into things.


  1. Hey Ja-Nae, this is a fascinating post, I also wanted to try and recreate the experiment but I haven't yet. I think I will tonight. I think this is one of the most interesting parts of the book.

  2. Hi Ja-Nae,
    Great post! I'm glad you tried this experiment on your own too, I feel like this is a good example of echolocation!