A millisecond is one thousandth of a second. Many screens show a new picture, called a frame, about every 17 milliseconds, so 33 milliseconds is two frames. That is far too short to read a sentence, but research shows it can be long enough for a word to register.
Scientists study this with a method called masked priming. A word flashes on the screen and is covered right away by a pattern, so the person cannot say what the word was. The researchers then measure whether the hidden word changed what the person did next.
Phillip Holcomb and Jonathan Grainger recorded brain activity while people saw words flashed this way. A word shown for 10 or 20 milliseconds left little trace. A word shown for 30 or 40 milliseconds clearly changed how the brain responded to the next word.
In 2023, a team led by Bernhard Angele ran a similar test online, on people’s own computers and phones instead of in a lab. A word flashed for about 17 milliseconds had no measurable effect. At 33 milliseconds the effect was clear, and at 50 milliseconds it was stronger.
A 33-millisecond flash can also shift what people say they want. In a 2015 study, 140 adults did a simple task on a computer while the words “Red Bull” flashed for 33 milliseconds, 30 times, each one covered right away by a row of letters. Afterward, they were asked how likely they would be to order Red Bull if they had to stay up late. They rated it higher than people who saw the same letters scrambled. The effect showed up only in people who enjoy excitement and new experiences, a trait researchers call sensation seeking.
Each of these effects was measured within minutes. Together they show that a very brief flash can register, but not that a single flash changes a person for long.
The results that lasted came from repetition spread over time. In a study led by Becca Levy at Yale, 100 adults between the ages of 61 and 99 took part in four short sessions, one week apart. In each session, positive words about aging, such as “spry” and “creative,” flashed by too quickly to read.
Over the following weeks, the participants came to see aging, and their own aging, more positively, and their physical function improved. The improvements were still there three weeks after the last session. They were also larger than the improvements in a group that received the same kind of encouragement openly.
The flashes in that study were longer than 33 milliseconds. Each person’s flash was set just below the speed they could notice, which averaged about 170 milliseconds, and a pattern covered each word. What the studies have in common is that the words registered, and the lasting change came from repeating them over weeks.
Seeing the words may matter, too. A review of 214 studies led by Wilhelm Hofmann looked at how people learn to like something when it is paired with something positive. The effects were stronger when people could see the positive words than when the words were hidden.
These effects were small, and each study tested specific people and specific words, so none of them can promise what will happen for any one person. What they describe is the kind of practice SOMOTE is built for: your own phrases on the screen you already look at, repeated hundreds of times a day, week after week.