"Tickling makes everyone laugh - and not just humans. We see this happen in other primates, such as chimpanzees, as well as other mammals. This suggests that laughter has deep evolutionary roots, possibly originating as part of playful communication between young infants and mothers," lead researcher Disa Sauter, of the department of psychology at University College London, said.
"Our study supports the idea that laughter is universally associated with being tickled and reflects the feeling of enjoyment of physical play."
The study is an extension of a previous research which suggests that facial expressions of the basic emotions such as laughter, surprise, anger are recognized across a wide range of cultures.
Britons and tribal people studied
To determine whether emotions such as happiness etc. are universal in nature, researchers from the University College London examined people of two separate cultures; one group comprised of Britons and the other involving more than 20,000 tribal people known as Himba, living in isolated part of Namibia in South-west Africa.
These tribal people had no access to electricity, running water, and they had never been exposed to other cultures or had any formal education.
For the study, the researchers narrated short stories based on a particular emotion such as sadness, fear or relief to both the Himba people and the European participants.
Then towards the end of each story, the participants in both the groups heard two sounds such as crying or laughter and were later asked to match the sound to the emotion reflected in the story.
The Himba group was made to listen to two records of a European voice and then asked to identify one sound--crying or laughter--which best suited the emotion in the story.
Likewise, the European participants listened to two records of a Himba voice and asked to choose that emotion which best fitted the story.
Europeans, Himba recognized laughter better
Analysis of the data revealed that the sounds of laughter were well recognized by participants of both the groups.
The Himba people faced some trouble while identifying other positive sounds except laughter, but they were easily able to recognize other basic emotions such as anger, fear, surprise etc.
On the other hand, the European participants were able to recognize all the sounds voiced by the Himba people.
"People from both groups seemed to find the basic emotions - anger, fear, disgust, amusement, sadness, and surprise - the most easily recognizable," researcher Sophie Scott, a professor at University College London, said. "This suggests that these emotions - and their vocalizations - are similar across all human cultures."
"One positive sound was particularly well recognised by both groups of participants: laughter. Listeners from both cultures agreed that laughter signified amusement, exemplified as the feeling of being tickled."
The study appears in the Journal Proceedings of National Academy of Sciences.