"For thousands of years humans have asked if we perceive the world accurately through our senses. From Plato onwards, we've wondered how our own cognition has influenced the messages we receive from our sense organs. Are we perceiving what is really out there? Because seeing is so important to our species, efforts to understand how perceptions are generated have most often focused on vision. This film explores the challenges of explaining visual perception. Using current information from neuroscience imaging techniques and lab based research, the film describes the profound technical and philosophical challenges scientists face in attempting to explain perception. The production includes overviews of the brain structures utilized to process sensory input and their neural connections to other brain regions, with an emphasis on visual perception. The essential role of cognition in interpreting sensory input is well demonstrated with intriguing visuals including optical illusions from the Purves lab at Duke University".
The DVD was released in September, 2008. For more information, visit Davidson Films.

“Vision is not what you think it is, and Dale Purves has done an unparalleled job in drawing careful attention to the way that we actually see the world. In this film he combines beautiful animations with memorable examples and to bring the issues fully to life.”
David M. Eagleman, PhD. Department of Neuroscience, Baylor College of Medicine

"This clear and accessible film will provide an excellent resource for both students and teachers of vision. The discrepancy between the image in the eye and what we actually perceive is demonstrated using a variety of compelling visual illusions that will both bewilder and amaze. A logical explanation for this discrepancy is then provided in a thought-provoking theory on how we make sense out of sensory information. An informative and stimulating introduction into the mysteries of sensory perception."
Timothy Andrews, PhD. Department of Psychology, University of York

"Dr. Dale Purves explains why—to offer a neuroscience twist on an old saw —believing is seeing. But the truth is that our eyes (in conjunction with the brain) deceive us, as anyone knows who has ever puzzled over one of those famous brain teasers, such as trying to determine which of two lines are “longer” (an illusion corrected by the application of a simple ruler). In the entertainment world, magicians and set designers have long capitalized on these so-called optical illusions in which perspective affects what we think we’re seeing, while more practical applications in the real world include supermarkets that spend serious money for lighting systems that make vegetables and meat appear fresher. Purves addresses the physiological aspect of how our visual perception differs from the physical reality of the world, and why we still function remarkably well despite these sensory discrepancies. Beginning with a look at how the eye captures light, as well as how the eye’s “rods” and “cones” work, Purves explains the science behind the ways that the brain compensates for (or makes sense of) what we perceive (for example, how we judge the relative sizes of objects, or even colors). Combining live-action footage and animation in numerous examples, along with cogent scientific explanation of various perceptual phenomena, this is recommended."
From Video Librarian