Tag: voice

Categories : NeurologyTags :

Recognising a Voice is Easier with a Face

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To recognise a famous voice, human brains use the same centre that is activated when the speaker’s face is presented, according to the results of an innovative neuroscience study which asked participants to identify US presidents.

The new study, published in the Journal of Neurophysiology, suggests that voice and face recognition are linked even more intimately than previously thought. It offers an intriguing possibility that visual and auditory information relevant to identifying someone feeds into a common brain centre, allowing for more robust, well-rounded recognition by integrating separate modes of sensation.

“From behavioural research, we know that people can identify a familiar voice faster and more accurately when they can associate it with the speaker’s face, but we never had a good explanation of why that happens,” said senior author Taylor Abel, MD, associate professor of neurological surgery at the University of Pittsburgh School of Medicine. “In the visual cortex, specifically in the part that typically processes faces, we also see electrical activity in response to famous people’s voices, highlighting how deeply the two systems are interlinked.”

Even though the interplay between the auditory and the visual brain processing systems has been widely acknowledged and investigated by various teams of neuroscientists all over the world, those systems were traditionally thought to be structurally and spatially distinct.

Few studies have attempted to directly measure activity from the brain centre – which primarily consolidates and processes visual information – to determine whether this centre is also engaged when participants are exposed to famous voice stimuli.

Researchers recruited epilepsy patients who had been implanted with electrodes measuring brain activity to determine the source of their seizures.

Abel and his team showed five participants photographs of three US presidents – Bill Clinton, George W. Bush and Barack Obama – or played short recordings of their voices, and asked participants to identify them.

Recordings of the electrical activity from the region of the brain responsible for processing visual cues (the fusiform gyri) showed that the same region became active when participants heard familiar voices, though that response was lower in magnitude and slightly delayed.

“This is important because it shows that auditory and visual areas interact very early when we identify people, and that they don’t work in isolation,” said Abel. “In addition to enriching our understanding of the basic functioning of the brain, our study explains the mechanisms behind disorders where voice or face recognition is compromised, such as in some dementias or related disorders.”

Source: University of Pittsburgh

Categories : Gender PaediatricsTags :

Is That A Girl’s Voice or A Boy’s?

On By ModernMedia
Phot by Ben Wicks on Unsplash

Researchers have found that it is possible to distinguish a girl’s voice from a boy’s from as young as five years old, but identification requires the listener to perceive the size of the speaker, providing a clue to their likely age. 

Perceiving gender in children’s voices is of special interest to researchers, because in children, a girl’s voice and a boy’s are very similar before the age of puberty. Adult male and female voices are fairly easy to distinguish due to acoustic differences.

With children, gender perception is much more complicated because gender differences in speech may emerge before sex-related anatomical differences between speakers. This suggests listeners may need to consider speaker age when guessing speaker gender and the perception of gender may depend on acoustic information besides anatomical differences between boys and girls.

In the Journal of the Acoustical Society of America, researchers reported developing a database of speech samples from children ages five to 18 to answer two questions: What types of changes occur in children’s voices as they become adults, and how do listeners adjust to the enormous variability in acoustic patterns across speakers?

Listeners assess a speaker’s gender, age, height, and other physical characteristics based primarily on the speaker’s voice pitch and on the resonance (formant frequencies) of their voice.

“Resonance is related to speaker height — think violin versus cello — and is a reliable indicator of overall body size,” said co-author Santiago Barreda, from the University of California, Davis. “Apart from these basic cues, there are other more subtle cues related to behaviour and the way a person ‘chooses’ to speak, rather than strictly depending on the speaker’s anatomy.”
When co-authors Barreda and Peter Assmann presented listeners with both syllables and sentences from different speakers, gender identification improved for sentences. They said this supports the stylistic elements of speech that highlight gender differences and are better conveyed in sentences.

They made two other important findings. First, listeners can reliably identify the gender of individual children as young as five.

“This is well before there are any anatomical differences between speakers and before there are any reliable differences in pitch or resonance,” said Barreda. “Based on this, we conclude that when the gender of individual children can be readily identified, it is because of differences in their behavior, in their manner of speaking, rather than because of their anatomy.”

Second, they found identification of gender of speakers must take place along with the identification of age and likely physical size.

“Essentially, there is too much uncertainty in the speech signal to treat age, gender, and size as independent decisions,” he said. “One way to resolve this is to consider, for example, what do 11-year-old boys sound like, rather than what do males sound like and what do 11-year-olds sound like, as if these were independent questions.”

Their findings suggest that “perception of gender can depend on subtle cues based on behaviour and not anatomy,” said Barreda. “In other words, gender information in speech can be largely based on performance rather than on physical differences between male and female speakers. If gendered speech followed necessarily from speaker anatomy, there would be no basis to reliably identify the gender of little girls and boys.”

This study supports the notion that gender (as opposed to sex) is largely performative in nature, which has long been argued on theoretical grounds.

Source: American Institute of Physics