12 April 2018
If you have a couple of minutes, click through to this survey site of “noisy gifs” – brief silent movies that, for some people at least, evoke illusory sounds. If you hear a thwack when fists collide with a punchbag, or a yell while watching a man silently scream, then you’re experiencing a “visual-evoked auditory response” (vEAR), also called “hearing motion synaesthesia”.
Ten years after the first, preliminary journal paper on the phenomenon, Christopher Fassnidge and Elliot Freeman at City University, London, report – in a new paper in Cortex – that it’s remarkably common, affecting perhaps 20 – 30 per cent of us. Fassnidge and Freeman also investigated what induces vEAR, providing clues to what’s going on the brain.
More than 4,000 volunteers, plus 126 paid participants, viewed 24, 5-second-long silent videos of real world scenarios and also more abstract images, such as shifting patterns. Using a scale of 0 to 5, they indicated how much auditory sensation they experienced for each video.
They also answered a series of other questions, including about past experience of vEAR and of any other synaesthesias (when a perception via one sensory modality triggers a sensory perception in another modality).