What is the Learning Curve? / by David Myers

Chances are if you’ve ever failed a test or had a particularly overbearing teacher you’ve heard all about the “learning curve”.   As an abstract concept it’s an easy way to explain why you didn’t do so well on that last quiz or just a way of saying it’ll take you a while to get accustomed to something.  In reality, the learning curve is an actual mathematical model which is used to predict the rate and accuracy at which people learn new material. The original idea came from studies run by Hermann Ebbinghaus (who did a lot of work in early psychology) when he would teach himself nonsense syllables each day and attempt to recall the syllables from the previous day.  The eventual result was a curve of how long it took him to learn the group of syllables he had given himself on a particular day.  Since then complete mathematical models have been established as a way to visually summarize the learning of a particular task or list. (If you’re interested in these models check out this paper [1]).

While the history behind the learning curve may not be super interesting what is impactful is the ways in which this learning curve can be shortened by studying techniques.  So what’s your normal routine? Go grab a large coffee, sit down at a quiet desk,  play music, and re-read everything until you know it? If this is your usual way of learning then you may have gotten a few things right but there’s always room for improvement.  For example, research has shown that caffeine is an effective way to stay alert and focused [2] but you’d be better off spacing out your studying over a period of time rather than trying to do it in one sitting [3]. There are all sorts of techniques and methods for studying which can cut down the learning curve which can be found all over the internet  some backed by science and others not but we’ll save that for another post.

What we find really interesting is the potential to cut down the learning curve using tDCS.  One study conducted a modern version of Ebbinghaus’s original learning and memory task.  For this experiment subjects underwent stimulation while learning a new vocabulary and those who received the real stimulation learned faster and retained the information better than those who didn’t receive stimulation. [4] An even more startling result of stimulation and learning are the results coming from the military’s use of tDCS to train soldiers.  The testing being done by the US military from their own made tDCS device has demonstrated a two fold increase in learning.  This means that they can cut the training time for soldiers in half!  There is a wonderful Radiolab podcast about tDCS ( found here [5]) which highlights the military use of the technology and its application.  With more studies involving tDCS and learning on the way, we can’t wait to see where this technology will lead us.