Five coffees could put you in a trance

A La Trobe University study has found stressed people who have five cups of coffee can exhibit signs of hallucination. File photo / Richard Robinson

Workers who rely on coffee to get through a stressful day in the office could start hallucinating, an Australian study claims.

A La Trobe University study has found stressed people who have five cups of coffee can exhibit signs of hallucination.

Professor Simon Crowe from the School of Psychological Sciences examined the effect of stress and caffeine on 92 participants.

He found stressed people who had drunk about 200mg of caffeine during the day were more likely to imagine hearing things.

"We brought people into the lab while listening to White Christmas and then told them we were going to play some white noise," he told mX newspaper in Australia.

"We also told them that within the white noise there may be parts of the White Christmas song and if you hear it, press the button.

"We didn't include White Christmas in the white noise but found that more people who were very stressed and had high levels of caffeine heard White Christmas."

In an office a caffeinated worker would be on edge and not correctly interpret situations, Professor Crowe said.

"They'll respond more to subtle cues but misidentify those cues.

"For instance, they may [mistakenly] believe that someone ... is talking about them and they will tend to overreact."

- NZ HERALD STAFF