According to recent studies, the human mind has a memory limit of about 3 to 4 items. This means that without doing any memory tricks, the average human can only remember 3 to 4 things at a time. These things may include numbers, names, or tasks. This short-term memory is also called the working memory. Without some form of memory aid, these 3 to 4 things will only remain in a person’s memory for about twenty seconds. Memory aids include repeating something over and over, placing items into groups or chunks, or writing things down. This is a revised theory about memory. Previously, scientists believed that the average human mind could remember about five to seven things at a time. Of course, some individuals have a stronger working memory than others. A stronger working memory is often related to a stronger ability to learn and problem solve.