2009 CHAST Lecture: Hearing Colours, Tasting Sounds: The Kaleidoscopic Brain of Synesthesia
David Eagleman New Law School, Lecture Theatre 101, University of Sydney Wednesday 3rd June 2009, at 6 pm Admission free Abstract: Imagine a world of magenta Tuesdays, tastes of blue, and wavy green symphonies. At least one in a hundred otherwise normal people experience the world this way in a condition called synesthesia. In synesthesia, stimulation of one sense triggers an experience in a different sense. For example, a voice or music are not only heard but may also be seen. Synesthesia is a fusion of different sensory perceptions: the feel of sandpaper might evoke a sensation of forest green, a symphony might be experienced in blues and golds, or the concept of February might trigger the perception of orange. Synesthetic perceptions are involuntary, automatic, and generally consistent over time. Most synesthetes are unaware their experiences are in any way unusual. Synesthesia comes in many varieties, and having one type gives you a high chance of having a second or third type. Experiencing the days of the week in color is the most common manifestation of synesthesia, followed by colored letters and numbers. Other common varieties include tasted words, colored hearing, numberlines perceived in three dimensions, and the personification of letters and numerals. We will concentrate here on musical forms of synesthesia, wherein pitches, chords or instrument timbres trigger the experience(s) of colors, textures or shapes. Synesthesia is the result of increased cross-talk among sensory areas in the brain, like neighboring countries on the brain's map with porous borders. Synesthesia has fascinated laypersons and scientists alike with its array of sensory amalgamations, but only recently has it been appreciated how the brains of such individuals yield surprising insights into normal brain function. Synesthesia is far more common than originally thought, and far more important scientifically than a mere curiosity. Evidence suggests that we are all synesthetic-but the majority of us remain unconscious of the sensory fusions going on our brains. After illustrating synesthesia in its wild variety of forms, I will show how my laboratory studies these experiences in the brain, using tools from genetics to advanced neuroimaging. Biography: David Eagleman is a neuroscientist at Baylor College of Medicine, where he directs the Laboratory for Perception and Action, as well as BCM's Initiative on Neuroscience and Law. He is the author of "Wednesday is Indigo Blue: Discovering the Brain of Synesthesia" (co-authored with Richard Cytowic) and three upcoming neuroscience books: "The Secret Life of the Unconscious Brain", "The Dynamically Reorganizing Brain", and a textbook on Cognitive Neuroscience. He is also the author of an internationally bestselling work of fiction, "Sum". http://www.chast.org/ _______________________________________________ SydPhil mailing list [email protected] 846 subscribers now served. To UNSUBSCRIBE, change your MEMBERSHIP OPTIONS, find ANSWERS TO COMMON PROBLEMS, or visit our ONLINE ARCHIVES, please go to the LIST INFORMATION PAGE: http://lists.arts.usyd.edu.au/mailman/listinfo/sydphil
