Vision

Neurophilosophy

Category archives for Vision

Ernst Haeckel’s Kunstformen der Natur (Artforms of Nature) was a landmark in biological illustration. Published in 1904, it was lavishly illustrated with 100 exquisitely detailed lithographic plates, including this one, showing nine different species of cubomedusae, or box jellyfish. It has been known, since around the time that Haeckel’s masterpiece was published, that box jellyfish…

Implied motion in Hokusai Manga

Click to enlarge images ARTISTS employ a number of different techniques to represent implied motion in two-dimensional works. One of these, commonly used in posters, comics and animation, is the affine shear effect, whereby a moving object is depicted as leaning into the direction of movement. Cartoonists also use action lines to depict movement and…

A novel temporal illusion, in which the cause of an event is perceived to occur after the event itself, provides some insight into the brain mechanisms underlying conscious perception. The illusion, described in the journal Current Biology by a team of researchers from France, suggests that the unconscious representation of a visual object is processed…

Visual analgesia: Seeing the body reduces pain

VISION is now well known to modulate the senses of touch and pain. Various studies have shown that looking at oneself being touched can enhance tactile acuity, so that one can discriminate between two pinpoints which would otherwise feel like a single sensation. And last year, researchers from the University of Oxford showed that using…

Nature’s fibre optics

THE retina has an inverted structure which seems ill-suited to its function: the rod and cone cells, which are sensitive to light, and which convert light energy into electrical impulses, point backwards and are located at the back of the retina, so that light entering the eye has to pass through several layers of irregularly…

If you look at a waterfall for about 30 seconds, and then shift your gaze to a nearby stationary object, such as a rock or a tree, that object will seem to drift slowly upwards. This well known optical illusion demonstrates a phenomenon called the motion after-effect, which is thought to occur as a result…

Reading the contents of working memory

Working memory refers to the process by which small amounts of information relevant to the task at hand are retained for short periods of time. For example, before cellular phones became so ubiquitous, calling someone usually involved first finding the number and then remembering it for a just few seconds by repeating it to oneself…

Visual images reconstructed from brain activity

Recent advances in functional neuroimaging have enabled researchers to predict perceptual experiences with a high degree of accuracy. For example, it is possible to determine whether a subject is looking at a face or some other category of visual stimulus, such as a house. This is possible because we know that specific regions of the…

The Men’s Final of the 1981 Wimbledon Tennis Championships is one of the most memorable events in sporting history. John McEnroe, who was playing against Bjorn Borg, famously challenged one of the referee’s calls by throwing a tantrum, during which he shouted the immortal line “You cannot be serious!” McEnroe’s outburst was controversial, and he…

An eye-opening view of visual development

The pioneering experiments performed by Hubel and Weisel in the late 1950s and early 60s taught us much about the development of the visual system. We now know, for example, that neurons in the visual cortex are organized into alternating ocular dominance columns which receive inputs from either the left or right eye and that…