Making things hard to read 'can boost learning'

Via BBC News, a somewhat counterintuitive finding: Making things hard to read 'can boost learning'. Excerpt:

Difficult-to-read fonts make for better learning, according to scientists. 

The finding is about to be published in the international journal Cognition. 

Researchers at Princeton University employed volunteers to learn made-up information about different types of aliens - and found that those reading harder fonts recalled more when tested 15 minutes later. 

They argue that schools could boost results by simply changing the font used in their basic teaching materials. 

Hard to digest 

The 28 volunteers in the Princeton study were given 90 seconds to try to memorise a list of seven features for three different species of alien. 

The idea was to re-create the kind of learning in a biology class. Aliens were chosen to be sure that none of the volunteers' prior knowledge interfered with the results. 

One group was given the lists in 16-point Arial pure black font, which is generally regarded to be easy and clear to read. 

The other had the same information presented in either 12-point Comic Sans MS 75% greyscale font or 12-point Bodoni MT 75% greyscale. 

The volunteers were distracted for 15 minutes, and then tested on how much they could remember. 

Researchers found that, on average, those given the harder-to-read fonts actually recalled 14% more. 

They believe that presenting information in a way that is hard to digest means a person has to concentrate more, and this leads to "deeper processing" and then "better retrieval" afterwards. 

It is an example of the positive effects of what scientists call "disfluency". 

"Disfluency is just a subjective feeling of difficulty associated with any mental task," explained psychology Prof Daniel Oppenheimer, one of the co-authors of the study. 

"So if something is hard to see or hear, it feels disfluent... We'd found that disfluency led people to think harder about things. 

"When we found that in the lab, we were very excited, because it has obvious implications for the classroom."

Not to mention implications for the website.