There is no such thing a ‘happy drunk’ scientists have concluded after finding that alcohol does not radically change personality.

Although many people blame drinking for alterations in their usual behaviour, new research shows that there is little shift in character between sober and squiffy.

In fact, the only change is that people become more extroverted. But it is simply a louder version of their usual personality.

"We were surprised to find such a discrepancy between drinkers' perceptions of their own alcohol-induced personalities and how observers perceived them," says psychological scientist Dr Rachel Winograd of the University of Missouri, St. Louis.

"Participants reported experiencing differences in all factors of personality, but extraversion was the only factor robustly perceived to be different across participants in alcohol and sober conditions."