We all know that feeling: you’re sitting on the train, contemplating the scenery as it whizzes past you. To make sure it doesn’t make us dizzy, our mind plays a trick on us; it briefly lets our eyes move along with the scenery and then jerks them back to their original position. The purpose of these eye movements – which from the outside are perceived as ocular tremors or nystagmus – is to stabilise moving images.
Manuel Holzer’s eyes are constantly shaking. He suffers from congenital nystagmus, a condition that affects around one in every 500 to 1000 people. It is usually diagnosed in early childhood and is almost always accompanied by other abnormalities such as diminished vision and disorders relating to head posture and line of sight. In Manuel’s case, squinting can also be involved, although there are two operations that can remedy this.