It may not have held back Jasper Carrot or Clare Short, although Sue Lawley did ditch hers the moment she left Dudley. Now a study suggests that other ambitious West Midlanders may want to consider losing their accent if they want to get on in life.

It found that people with the distinctive nasal tones of the Birmingham region are considered far less intelligent than those with other accents, despite a general trend in which regional dialects have become more respectable.

In a series of experiments, even a control group who said nothing at all were considered more intelligent than those with Brummie accents.

The study into dialect and perceived intelligence also found that received pronunciation, the accent of royalty and public school alumni, has fallen from its leading role for the first time.

The research was conducted at Bath Spa University by Lance Workman and Hayley-Jane Smith, who comes from Birmingham. In their experiments, the Yorkshire accent came top.

They undertook the study to see if the stigma attached to regional accents had diminished. Dr Workman said: “The results certainly show some regional accents no longer have the stigma they once did and are now perceived to carry wisdom and intelligence. Unfortunately the Birmingham accent was received so negatively it was ranked as less intelligent than silence.” The research will be presented today at the British Psychological Society’s annual conference in Dublin.

In the experiment, participants were shown pictures of young women and a recording of what they were told were their voices, discussing how they liked to spend their time. The pictures and recordings were mixed up to control for visual taste, although the women were all “averagely attractive”.

Participants were asked to rank the women first for attractiveness, then for intelligence out of a total score of 10. The women with the Yorkshire accent scored 6.71 on intelligence while those with received pronunciation scored 6.67. The silent women scored 5.99 and the Brummies 5.6.

“This is the first time a regional dialect has been perceived as more intelligent than received pronunciation,” Dr Workman said. “I think there are a couple for reasons for this. The BBC and other mass media have shifted towards using newsreaders with regional accents, and people reading the news are usually seen as authoritative and intelligent.” The popular portrayal in recent years of upper-class figures as dim had also undermined perceptions of received pronunciation.

Dr Workman said that research showed that people associated the Birmingham accent with high levels of criminality and untrustworthiness. “The Birmingham accent is clearly taking longer than others to evolve culturally,” Dr Workman said.

Midlanders still manage to get ahead, actually

— Cat Deeley – MTV presenter and host of British editions of American Idol, she is now fronting the US series So You Think You Can Dance?

— Johnnie Walker – Radio Caroline DJ who joined BBC and presented Radio Two’s drive-time programme. Currently presents a Sunday rock show

— Murray Walker – the former Formula One commentator became famous for his “engine” voice which rose and fell like a racing car.

— Adrian Chiles – host of Match of the Day 2 and The Apprentice spin-off You’re Fired. Sick of question: “How have you managed to get on with a Birmingham accent?”

— Alan Dedicoat – Off-screen “voice of the balls” on the televised National Lottery draw and Radio Two newscaster

— Frank Skinner – comedian and overrevealing autobiographer

— Lenny Henry – child Opportunity Knocks winner, comedian and actor

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