A metadisease, and one of the symptoms is this feeling of lurching forward, like a sudden jolt in a car or a train. Other symptoms include seeing parallel selves, mild climate fluctuations on street sidewalks, and seeing the hand of a god reaching down and scraping the hillsides.
Treatment and cure are still in the early research stages, hampered by cognition and awareness being common infection vectors, but keeping a recording with saxophone as one of the instruments on one's person seems to be an effective prophylactic.
This is the excuse I've always needed to play Men at Work's 1981 smash hit Who Can It Be Now? over and over and over again