While Siri and Alexa rely on a plethora of components and cloud servers to work out what people are saying, our brain can do it with a tiny area, researchers have revealed.
We are able to distinguish Donald Trump’s speech from the voice of our mother due to a section of the right posterior temporal lobe, one of the four major lobes in a mammalian brain, new research from a German university has found.
Scientists have long disagreed on the exact area responsible for voice recognition, but they now believe it all takes place in a tiny area is known as the superior temporal gyrus (STG).
Scientists have long disagreed on the exact area responsible for voice recognition, but they now believe it all takes place in a tiny area is known as the superior temporal gyrus (STG), marked in red on this image
In a study of 58 patients with brain injuries, the researchers found that some of those who had lesions in the right posterior temporal lobe had difficulty recognizing other people’s voices.
People who had had a stroke were even more likely to not recognize a voice.
‘Very valid statements about which brain areas are responsible for which functions are derived from investigations in patients with lesions, said Claudia Roswandowitz, scientist at the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in Leipzig, who led the research.
The injury-related loss of function helped shed light on the crucial section of the temporal lobe, which the study’s authors now believe is crucial to voice recognition.
Out of the people examined, 9 percent had some sort of trouble distinguishing one voice from another.
According to the study’s authors, the number is significant enough to suggest that the STG plays a role in how humans hear a voice.
Additionally, the scientists looked at brain scans of the participants.
These findings were supported by a previous study at MPI CBS, whereby, a phenomenon commonly known as ‘voice blindness’, phonagnosia, the inability to recognize voices, was investigated.
The find shows just how complex our brain is – needing just a tiny area of its mass to perform calculations that the most advanced technology such as Siri requires huge amounts of hardware and processing power to do
The two involved study participants – the only ones known in Germany to be affected by phonagnosia – were not able to identify people by voice, even their own mum or child.
Roswandowitz and her colleagues also detected that changes in and to the right temporal lobe led to the corresponding deficits.
In comparison to the other patients with lesions, the causes did not lie in the failed brain structures but rather in their different brain activity.
‘These findings improve our understanding of how the brain identifies voices and provide the basis in the search for effective therapies for those affected by phonagnosia, a fairly common deficit which is sometimes present from birth but especially after a stroke.
‘In our studies nine per cent of the participants reported suffering from difficulties in recognizing voices, a problem that is almost unheard of in the medical sector.
Thus, we have to raise awareness of this matter’, says Roswandowitz.