Researchers found that briefly displaying words and images so quickly that people do not even consciously notice, does nevertheless change their thinking.
They found it was particularly effective with negative images and words which could alter a person's mood.
The phrase subliminal advertising was coined in 1957 by the US market researcher James Vicary, who said he could get moviegoers to "drink Coca-Cola" and "eat popcorn" by flashing those messages onscreen for such a short time that viewers were unaware.
His claims led to fears that governments and cults would use the technique to their advantage and it was banned in many countries, including the UK.
Vicary later admitted he had fabricated his results.
But more than 50 years on British researchers have shown messages we are not aware of can leave a mark on the brain.
A team from University College London, funded by the Wellcome Trust, found that it was particularly good at instilling negative thoughts.
"There has been much speculation about whether people can process emotional information unconsciously, for example pictures, faces and words," said Professor Nilli Lavie, who led the research.
"We have shown that people can perceive the emotional value of subliminal messages and have demonstrated conclusively that people are much more attuned to negative words."
In the study, published in the journal Emotion, Professor Lavie and colleagues showed fifty participants a series of words on a computer screen.
Each word appeared on-screen for only a fraction of second - at times only a fiftieth of a second, much too fast for the participants to consciously read the word.
The words were either positive (e.g. cheerful, flower and peace), negative (e.g. agony, despair and murder) or neutral (e.g. box, ear or kettle).
After each word, participants were asked to choose whether the word was neutral or "emotional" (i.e. positive or negative), and how confident they were of their decision.
The researchers found that the participants answered most accurately when responding to negative words - even when they believed they were merely guessing the answer.
Professor Lavie believes that the ability to subconsciously pick up fleeting signals could have developed as a way of picking up fleeting warnings.
"Clearly, there are evolutionary advantages to responding rapidly to emotional information," she said.
"We can't wait for our consciousness to kick in if we see someone running towards us with a knife or if we drive under rainy or foggy weather conditions and see a sign warning ‘danger'."
Professor Lavie believes the research may have implications for the use of subliminal marketing to convey messages, both for advertising and public service announcements such as safety campaigns.
"Negative words may have more of a rapid impact," she said.
""Kill your speed" should be more noticeable than "Slow down". More controversially, highlighting a competitor's negative qualities may work on a subliminal level much more effectively than shouting about your own selling points."
Subliminal advertising is not permitted on TV in the UK, according the broadcasting regulator Ofcom. However, there have been a number of cases where the rules been stretched.
In one particularly infamous case in 1997, comedian Chris Morris used a half-frame caption at the end of the satirical show Brass Eye to criticise the chief executive of Channel 4, Michael Grade, for heavily editing the controversial programme.
The description of his boss - "Grade is a ****" - would certainly have fallen into the category of negative words as described in Professor Lavie's research.