Episode four explores how our perception of the world is changed by neurological conditions, social cues and the unconscious mind. Featured documentary Synaesthesia: Hidden Worlds of Colour by Jake Kohler, offers insight into the colourful minds of those with synaesthesia by exploring how they perceive the world. This episode also includes a compelling interview with Associate Professor of Screen Studies, Dr. Felicity Collins, who explains how a unique interconnection of the senses enables us to perceive films.