According to The Guinness Book of World Records, the toughest tongue twister is 'The sixth sick sheik's sixth sheep's sick.' However, if researchers from the Massachusetts Institute of Technology are to be believed, there may be a new contender for that coveted spot.

Dr. Stefanie Shattuck-Hufnagel and her team assert that 'pad kid poured curd pulled cold' is the toughest tongue twister that has ever been concocted. In fact, it is so difficult that when people were asked to repeat it rapidly ten times, they became so tongue-tied that they stopped speaking altogether. The twister revealed at the Fall Meeting of the Acoustical Society of America that was held in San Francisco from December 2nd-6th, was part of a study conducted by Stefanie's team to get some insight into the human brain's speech planning process.

The researcher says that for some reason, when certain words are spoken together quickly, people seem to lose control, and more often than not, the one sound seems to replace the other. For example, try saying toy boat fast a few times, and you will soon start pronouncing the words as 'toy boyt'! Similarly, 'top cop' seems to rapidly turn into 'cop cop!'

How the brain processes each tongue twister also seems to depend on if it comprises of a few words or is a full sentence. In the former case, the tongue often ends up saying just the first letter of the first word-like tkop instead 'top cop,' while in the case of the latter, it sounds like 'tah-kop.' While not sure, they believe it may have something to do with the regular rhythm of a word list as compared to the somewhat irregular timing of a sentence.

The MIT team plan to continue their research by placing tiny transducers on the tongues of volunteers and measuring their articulation to try to gain further insight. Meanwhile, we can all drive people around us a little crazy by continually repeating a phrase that even the researchers agree makes no sense.

'pad kid poured curd pulled cold'

Resources: Huffingtonpost.com, dailymail.co.uk