"Our findings upend what has been universally accepted in the scientific community - that we use only one side of our brains for speech," said Bijan Pesaran, associate professor at New York University's centre for neural science.
"Since we have a firm understanding of how speech is generated, our work toward finding remedies for speech afflictions is much better informed," added Pesaran in a study that appeared in the journal Nature.
The researchers examined brain functions of patients suffering from epilepsy by using methods that coincided with their medical treatment.
In their examination, the researchers tested the parts of the brain that were used during speech.
The participants were asked to repeat two non-words - 'kig' and 'pob'.
Using non-words as a prompt to gauge neurological activity, the researchers were able to isolate speech from language.
An analysis of the brain activity as patients engaged in speech tasks showed that both sides of the brain were used - that is, speech is, in fact, bi-lateral.
"Recordings directly from the human brain are a rare opportunity," said Thomas Thesen, director of the NYU Langone Medical Centre in Manhattan, NY.
"Now that we have greater insights into the connection between the brain and speech, we can begin to develop new ways to aid those trying to regain the ability to speak after a stroke or injuries resulting in brain damage," observed Pesaran.
The findings lay the groundwork for better rehabilitation methods for such patients.