Can you “hear” motion or light flashes? If so, according to new research from City University London, you may be experiencing a not-so-rare form of synaesthesia. Synesthesia is the fascinating neurological phenomenon whereby stimulation of one sense involuntarily triggers another sensory pathway. For example, a synesthete might taste sounds or hear colors. (In this study, 8 out of 40 participants, a very high percentage, were considered to have hearing-motion synaesthesia.) Here is their test for you to take yourself. From The Guardian:
(This new study) suggests that many more of us experience a less intrusive version of (synesthesia) in which visual movements or flashes are accompanied by an internal soundtrack of hums, buzzes or swooshes. Since movements are very frequently accompanied by sounds in everyday life, the effect is likely to be barely discernible.
When tested under laboratory conditions, the “hearing motion” effect appeared to enhance a person’s ability to interpret fine visual movements, but also interfered with the ability to hear real sounds when visual and audio signals were mis-matched.
“These internal sounds seem to be perceptually real enough to interfere with the detection of externally-generated sounds,” said Freeman. “The finding that this ‘hearing-motion’ phenomenon seems to be much more prevalent compared to other synaesthesias might occur due to the strength of the natural connection between sound and vision.”
In a separate study, the team tested for the phenomenon in trained musicians and found that it was much more common in the group. It is not clear if this is due to a natural disposition to link sounds and visual cues or whether thousands of hours of training might have strengthened the neural circuitry behind the effect.