Examples

• Movie box office charts - "inspired by stream graphs and the works of Edward Tufte." Very cool.
• Wayfinding - here's a great example of how a designer thinks visually: "anamorphic words that only line up when you're correctly positioned." The photos are very striking.
• Future Browser - here's a short video about what a browser of the future might look like and be capable of; not surprisingly, it's a case study in visual reasoning, as marshalling large amounts of information depends upon good visual design.

Resources

• Visual reasoning - the Wikipedia entry is sadly neglected
• Visual reasoning at Washington State University
• andDesign Blog this just came through on my Google alerts and it looks like it might have quite a bit of interesting information and argumemts. It was a little slow and sticky when I tried to navigate around in the site and I'm not sure why.
• Visual and Spatial Reasoning in Design This is a little treasure trove of articles from a conference at MIT in 1999: Goldschmidt, Kosslyn, Tversky...
• Cartography as a metaphor for Web design - the author suggests that we've been using architecture as the guiding metaphor for Web design, but that this metaphor views space as empty and in need of populating. Rather, though, space is productive and is better thought of something in need of mapping.
  
• Optical Illusions - The Spinning Dancer on wikipedia with links to other illustions, e.g. the Decker Cube.
• Sight and sound - a few articles on how hearing synergizes vision. "Sound Adds Speed To Visual Perception" - "A new study shows that, in monkeys, the region involved in hearing can directly improve perception in the visual region, without the involvement of other structures to integrate the senses." "Wired For Sound: How The Brain Senses Visual Illusions" - "In a study that could help reveal how illusions are produced in the brain's visual cortex, researchers at the UCSD School of Medicine have found new evidence of rapid integration of auditory and visual sensations in the brain. Their findings... provide new insight into neural mechanisms by which visual perception can be altered by concurrent auditory events." "How Ventriloquists Trick The Brain: Sight, Sound Processed Together And Earlier Than Previously Thought" - "The area of the brain that processes sounds entering the ears also appears to process stimulus entering the eyes, providing a novel explanation for why many viewers believe that ventriloquists have thrown their voices to the mouths of their dummies."
• Eyes Evolved For 'X-Ray Vision' - This research supports something Arnheim says at the beginning of Visual Thinking (but I need to supply the quote!). "Humans and other large mammals — primates and large carnivores like tigers, for example — exist in cluttered environments like forests or jungles, and their eyes have evolved to point in the same direction. While animals with forward-facing eyes lose the ability to see what's behind them, they gain X-ray vision, according to Mark Changizi, assistant professor of cognitive science at Rensselaer, who says eyes facing the same direction have been selected for maximizing our ability to see in leafy environments like forests."
• Red or white? - put red food color in a glass of white wine and guess what? You can fool even a so called expert wine taster. We have a saying, You are what you eat. Perhaps, but even more, We think what we see. One of many studies is described here.
• Size doesn't matter - spacing, not size, is critical to recognizing an array of crowded objects.
• Optical illusions - a series of article in Scientific American; here's the fourth.
• 3D perception - "higher-level visual regions of the brain represent objects as spatial configurations of surface fragments, something like a structural drawing. Individual neurons are tuned to respond to surface fragment substructures. For instance, one neuron from the study responded to the combination of a forward-facing ridge near the front and an upward-facing concavity near the top. Multiple neurons with different tuning sensitivities could combine like a three-dimensional mosaic to encode the entire object surface."
• Emotion and vision - Facial Expressions Of Emotion Are Innate, Not Learned: "Facial expressions of emotion are hardwired into our genes, according to a new study. The research suggests that facial expressions of emotion are innate rather than a product of cultural learning. The study is the first of its kind to demonstrate that sighted and blind individuals use the same facial expressions, producing the same facial muscle movements in response to specific emotional stimuli."
• Perception and motion - How We Make Proper Movements: "When you first notice a door handle, your brain has already been hard at work. Your visual system first sees the handle, then it sends information to various parts of the brain, which go on to decipher out the details, such as color and the direction the handle is pointing. As the information about an object is sent further along the various brain pathways, more and more details are noticed—in that way, a simple door handle turns into a silver-plated-antique-style-door-handle-facing-right.... These results indicate that there is a common mechanism which acts in both perception and movement."
• Learned Motor Programs Directly Influence The Visual Perception of Movements - "When novel movements are learned--for example, in sports--visual and motor learning take place simultaneously. A karate master not only executes a kick better than a beginner, but he also perceives karate movements much more accurately. A variety of recent studies suggest that motor programs may influence the visual recognition of movements."
• Speech perception - Scientists Watch As Listener's Brain Predicts Speaker's Words. This is a clear case of perceptual "thinking" or cognition. "Scientists at the University of Rochester have shown for the first time that our brains automatically consider many possible words and their meanings before we've even heard the final sound of the word."
• Autism and vision - "Joint Attention Study Has Implications For Understanding Autism": "A hallmark of human nature is the ability to share information and to comprehend the thoughts and intentions of others. This capability involves social cognition (the cognitive processes involved in social interaction) and makes a significant contribution to the foundations for language development, as well as social competence. It also sets us apart from other primates." "Children With Autism May Learn From 'Virtual Peers'": Using "virtual peers" -- animated life-sized children that simulate the behaviors and conversation of typically developing children -- Northwestern University researchers are developing interventions designed to prepare children with autism for interactions with real-life children. "Direct Gaze Enhances Face Perception": "As atypical emotional reactions to various social stimuli, for instance other people’s facial expressions, most likely play a key role in different types of mental disorders, the knowledge generated by the research project also provides an opportunity to develop efficient methods for the diagnosis and treatment of mental disorders."
• Subliminal sex? Erotic Images Prove Useful In Coaxing Out Unconscious Brain Activity: " 'Selective attention helps us to quickly process what is important while ignoring the irrelevant,' the researchers write. 'In this study, we demonstrate that information that has not entered observers' consciousness, such as [invisible] erotic pictures, can direct the distribution of spatial attention. Furthermore, invisible erotic information can either attract or repel observers' spatial attention depending on their gender and sexual orientation.' "
• Eye movement controls visual attention: "With so many visual stimuli bombarding our eyes -- cars whizzing by, leaves fluttering -- how can we focus attention on a single spot -- a word on a page or a fleeting facial expression? How do we filter so purely that the competing stimuli never even register in our awareness?" See also: Researchers Resolve 40-year Eye Movement, Visibility Controversy.
• Mathematics - WSU prof Duane DeTemple talks about the beauty of math in this short video, and how he tries to get his students to thinking creatively about mathematics.
• Brain: both sides now - musicians are better at divergent thinking and creative, "out of the box" solutions.