KISSmetrics say:

According to Daniel Kahneman, a Nobel Prize-winning researcher, the brain has two different systems for making decisions. There’s the conscious system, where we think decisions through and make decisions carefully.

Then, there’s the “instant decision” brain. According to Kahneman, you tend to believe your first impressions, then take actions based on the desires those first impressions create.

We live in an “instant decision” culture. This is especially true of online reading. Technology trains us to quickly judge webpages, and then move on to something else if it doesn’t interest us. Remember, 17% of page views do last for more than four seconds.

In fact, other studies have shown that our average attention spans have been reducing over time and in this particular study, it is just six seconds.

How does that apply to your blog? It’s simple: You need to be extremely conscious of your blog’s first impression. Where do the eyes gravitate when someone lands on your blog for the first time?

What kind of information can someone glean at a glance? Can users tell what your blog is about without having to read carefully?

You have about five seconds to catch your reader’s attention. If you can’t present a compelling reason for why they should stay in about five seconds, they’re going to leave.

How Long Should a Headline Be?The headline of a post is one of the most prominent parts of a page. If you have a header, the header should have a tagline that conveys your blog’s subject matter.

Alternatively, if it’s just a graphical header, it should be small and unobtrusive. The header shouldn’t compete with the post’s headline for attention.

A recent study by Outbrain illustrates how headline length can be linked to user engagement. The highest CTRs were witnessed for articles that had moderate headline lengths (16-18 words).

The Scientific Reason Why Simple Is Better

The primary reason why less visually complex websites are perceived as more beautiful is because we don’t require our eyes and brain to work as hard to decode, process and store the data.

To learn more about this, watch this video that explains how our eyes communicate with our brain.

What Font Should You Use?

Typography is an important part of your design, and there’s a lot of conflicting information about what font you should use. Fortunately, science is here to help.

In a joint study by IBM and Google, researchers conducted a comprehensive study titled “Study of How Font Size and Type Influence Online Reading.” The study was conducted by asking subjects to read a number of science news articles written at an eighth-grade level.

The study included both men and women and spanned a large age range. The study also included readers for whom English was not their first language. The results were adjusted for all these factors.

Here’s what the study found:

• On small fonts, people tended to spend more time on each fixation (“gulp” of an eye, usually a group of three to six words). This was most likely because words were more difficult to make out, which meant people had to spend more time and energy on each word. Fonts sized 10 and below had this problem.
• On larger fonts, people had smaller and more frequent fixations. That means they were taking in fewer words per “visual gulp.”
• The serif font, Georgia, was read 7.9% faster than the sans serif font Helvetica, although this difference is not significant.

so which font?

Apparently which Font doesn't matter because the difference is not significant.

Master the Use of White Space

Researchers from Wichita State University conducted a detailed study on white space. Eighty-nine percent of the participants were active Web users who surfed the Web daily.

Eleven percent of the group used the web for 25-plus hours a week and 26% read for at least seven hours a week. The reading text was taken from SAT and ACT practice exams.

The researchers had participants read passages with a lot of margin (white space) around the text, as well as varied the text in between lines of text. Here’s what the study found.

• Space between lines of text did not affect reading speed or comprehension. However, after the study, participants reported being less satisfied with pages that had less spacing between text. In other words, people can still read poor spacing – they just won’t like your site as much.
• No or low margin text was read faster, but had lower comprehension. Putting a good amount of white space around your text gets people to read a little slower, but makes them understand the material a lot more.