D'oh! We have 30 'Homer-esque' moments every week

Such 'd'oh moments' - named after cartoon character Homer Simpson's catchphrase - are said to strike as often as 30 times a week.

Even those who are not scatty suffer an average of six memory blanks a week, researchers found.

They said the lapses may become more common as people lead ever busier and more stressful lives. Lead researcher Maria Jonsdottir and her team of Finnish psychologists came up with the figures after asking 189 volunteers aged between 19 and 60 to record their lapses.

Weekdays between noon and 8pm were the peak time for blunders with age, gender or intelligence making little difference to the results.

Dr Jonsdottir said: "What we call action slips or mental lapses usually happen in the context of well-rehearsed or routine action sequences that we usually can perform pretty successfully without paying attention.

"They probably reflect some temporary fault in this otherwise very efficient system, much like when we mispronounce words or use the incorrect word in our native tongue.

"Somehow the brain has to be at fault though an action slip doesn't mean that something is wrong per se with that person's brain."

The authors of the report divided action slips into five different categories, the most common of which was labelled a "storage failure".

Examples include people remembering they had to call someone but forgetting who. The remaining four categories of blunders identified included "test failures", such as trying to turn on a light that was already on and "discrimination failures", like putting on a partner's clothing by accident.

Dr Jo Iddon, co-author of the Memory Booster guide, said the research would offer reassurance for those worrying about their memory.

"We all think we have a worse memory than we do," she said. "This research is useful because it shows we all make these odd mistakes."

The full findings will appear in the journal Clinical Neuropsychologist later this year.