IT'S not quite pink elephants floating along the hallways but workers who rely on coffee to get through a stressful day in the office could find themselves hallucinating.

A La Trobe University study has found stressed people who have consumed 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.



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



"What we did is 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.



"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 environment, a caffeinated worker would be on edge and not correctly interpret situations, Prof Crowe said.



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



"For instance, they may (mistakenly) believe that someone around the water cooler is talking about them and they will tend to overreact."