Memory and Math
Why do students with poor working memory have more difficulty doing horizontal math problems versus vertical ones?
– Lauren, Richmond, VA
Visuo-spatial memory functions like a mental blackboard: visual information is recorded and kept active for a short period of time. When math problems are presented horizontally, a student has to rely on their working memory to carry numbers correctly to solve the problem. When solving horizontal math problems, you may notice that a student with poor working memory will make very simple mistakes, such as forgetting to carry the number, or adding up the sum without the carried number.
Teachers often tell me that they don’t understand why this student keeps making the same mistakes when they have told him/her how to solve math problems many times. Do not be surprised to discover that techniques such as repetition won’t be very useful here as students with poor visuo-spatial memory have difficulty in visualizing numbers.
A simple technique to help a student to better visualize the math problem and take off the pressure from their visuo-spatial working memory is to present the problem vertically. Here is an example:
Give your student a math problem such as 18 + 24 = __ written out horizontally. Then ask them to write it vertically as
18
+ 24
____
Initially, it is not necessary that they solve the problems, only that they write it vertically. If you like, you can ask them to solve the problems once they are confident writing it down.
