The subject of Carey Born’s film is amusing, engaging and more than a little preposterous. It is about the talented artist and musician Neil Harbisson, who has colour blindness and has had an antenna fitted into the back of his skull – invented by cyborg tech specialist Adam Montandon – which loops over his head and bobs about in front of his face roughly at eye level, converting colour into sounds so that he can “hear” these colours inside his head.

Born’s film takes with absolute seriousness his claim that he is a “cyborg” at the forefront of a new transhuman age, although most of the people shown interviewing him end up having the same facial expression: intrigued, amused, politely sceptical. The one person who is actually shown putting him to any sort of test is Richard Madeley, in a 2004 episode of the Richard and Judy Show; Madeley presents him with an apple painted blue and asks him to divine what colour it is, by putting his microphone close to the object, and listening to the resulting note. Harbisson passes with flying colours, although a more interesting and rigorous test would surely require him to do it blindfolded, to show that he’s not just a person with ordinary colour vision pranking us?

Later, we discover that Harbisson is marketing various objects that supposedly allow people to extend their sensory perceptions and partake of the radical new cyborgism. One of these is “North Sense”, a device you place on your skin which vibrates when you face north. (Erm, why is this any better than a compass app on your smartphone, or even an actual, analogue, real-world compass?) Harbisson’s public persona is entertaining, maybe best appreciated as conceptual performance art.

• Cyborg: A Documentary is in UK cinemas from 20 September.