London, March 8 : The results of a brain-scanning study suggest that impressionists visualise images of the people they mimic.
Sophie Scott, who led the study at the Institute of Cognitive Neuroscience at University College London, used an fMRI brain scanner to screen impressionist Duncan Wisbey's brain while he was repeating phrases in a variety of different voices-including that of actor Cary Grant and the British TV chef Anthony Worrall Thompson.
The accents impersonated by Wisbey also included "baleful Cockney" and "tired Australian".
Scott also asked Wisbey to repeat the same phrases in his own voice.
The researcher observed an increased activity in the parietal lobe, sensory motor strip and supplementary motor areas of Wisbey's brain when he was imitating others.
Scott said that all those areas were respectively involved in visual imagery, body representation and vocalisation.
"For basic speech production, his results are normal. The extra activities (when doing impressions) are in very plausible areas. These areas are known to be active in mental imagery tasks," New Scientist magazine quoted her as saying.
Based on her observations, Scott came to the conclusion that Wisbey was using visual images to imagine the people he was imitating, including their mannerisms, and all that guided his impressions.
Interestingly, Scott's suggestion matched up with Wisbey's own description of how he did impressions.
Telling about how he mimicked Anthony Worrall Thompson, Wisbey said: "(I create) a constriction of the neck, and I'm actually pushing the shoulders upwards and pushing my head down. My lower lip is protruding forwards, but I'm doing a sort of smile - just like the Joker from Batman."
Matt Davis, a speech and language researcher at the MRC Cognition and Brain Sciences Unit in Cambridge, hailed Scott's study as "interesting".
He, however, stressed the need to study more impressionists, saying that they might be using different techniques.
"It might be that Wisbey achieves his skill in a distinctive way," he said.
Scott is now recruiting other voice artists and impressionists to undergo the same procedure.
She and Wisbey will be presenting the results as part of a talk for Brain Awareness Week on 11 March.