Upside down goggles, also known as "invertoscopes" by Russian researchers, [1] are optical instruments that invert the image received by the retinas upside down. They are used to study human visual perception, particularly psychological process of building a visual image in the brain. Objects viewed through such a device appear upside down and mirrored. They are constructed using sets of optical right-angle prisms, concave mirrors, or a mirror plus right-angle prisms with unequal cathethus.
Upside down goggles can be used to demonstrate human adaptation to inverted vision, and as a method of preventing motion sickness. [2] Hubert Dolezal recommended using upside down goggles for "nausea adaptation" for space travel. [3]
They can also be used to train spatial abilities and possibly cognitive functions. [Patents of devices 1]
Under normal circumstances, an inverted image is formed on the retina of the eye. With the help of upside down goggles, the image on the retina of the observer's eyes is turned back (straightened) and thus the space around the observer looks upside down. [4]
George M. Stratton designed the first upside down goggles for a psychological experiment. His device used short-focus lenses. Stratton used a one-tube, monocular device because this also reverses left and right and he wished to set up an experiment without distortion of depth perception. [5]
In 1931 Theodor Erismann and Ivo Kohler conducted a series of experiments using mirror-prismatic upside down goggles employing only one mirror. [6]
After experimenting since 1984, in 1991 Hubert Dolezal procured a US patent for comfortable light weight upside down goggles. [Patents of devices 2]
Modern upside down goggles consist of two prisms fixed onto a comfortable ski mask-like base.
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. Light is a type of electromagnetic radiation, and other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.
A camera obscura is the natural phenomenon in which the rays of light passing through a small hole into a dark space form an image where they strike a surface, resulting in an inverted and reversed projection of the view outside.
Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes when viewing distant objects. Most binoculars are sized to be held using both hands, although sizes vary widely from opera glasses to large pedestal-mounted military models.
Night vision is the ability to see in low-light conditions, either naturally with scotopic vision or through a night-vision device. Night vision requires both sufficient spectral range and sufficient intensity range. Humans have poor night vision compared to many animals such as cats, dogs, foxes and rabbits, in part because the human eye lacks a tapetum lucidum, tissue behind the retina that reflects light back through the retina thus increasing the light available to the photoreceptors.
Color constancy is an example of subjective constancy and a feature of the human color perception system which ensures that the perceived color of objects remains relatively constant under varying illumination conditions. A green apple for instance looks green to us at midday, when the main illumination is white sunlight, and also at sunset, when the main illumination is red. This helps us identify objects.
A pentaprism is a five-sided reflecting prism used to deviate a beam of light by a constant 90°, even if the entry beam is not at 90° to the prism. The beam reflects inside the prism twice, allowing the transmission of an image through a right angle without inverting it as an ordinary right-angle prism or mirror would.
An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — elements with two parallel surfaces are not prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides. Not all optical prisms are geometric prisms, and not all geometric prisms would count as an optical prism. Prisms can be made from any material that is transparent to the wavelengths for which they are designed. Typical materials include glass, acrylic and fluorite.
An afterimage is an image that continues to appear in the eyes after a period of exposure to the original image. An afterimage may be a normal phenomenon or may be pathological (palinopsia). Illusory palinopsia may be a pathological exaggeration of physiological afterimages. Afterimages occur because photochemical activity in the retina continues even when the eyes are no longer experiencing the original stimulus.
The Thatcher effect or Thatcher illusion is a phenomenon where it becomes more difficult to detect local feature changes in an upside-down face, despite identical changes being obvious in an upright face. It is named after the then British prime minister Margaret Thatcher, on whose photograph the effect was first demonstrated. The effect was originally created in 1980 by Peter Thompson, professor of psychology at the University of York.
In photography, a viewfinder is a device on a camera that a photographer uses to determine exactly where the camera is pointed, and approximately how much of that view will be photographed. A viewfinder can be mechanical, with simple optical components, with precision optics and optical functions, or a digital accessory device used with digital cameras.
A pseudoscope is a binocular optical instrument that reverses depth perception. It is used to study human stereoscopic perception. Objects viewed through it appear inside out, for example: a box on a floor would appear as a box-shaped hole in the floor.
Neural adaptation or sensory adaptation is a gradual decrease over time in the responsiveness of the sensory system to a constant stimulus. It is usually experienced as a change in the stimulus. For example, if a hand is rested on a table, the table's surface is immediately felt against the skin. Subsequently, however, the sensation of the table surface against the skin gradually diminishes until it is virtually unnoticeable. The sensory neurons that initially respond are no longer stimulated to respond; this is an example of neural adaptation.
Visual neuroscience is a branch of neuroscience that focuses on the visual system of the human body, mainly located in the brain's visual cortex. The main goal of visual neuroscience is to understand how neural activity results in visual perception, as well as behaviors dependent on vision. In the past, visual neuroscience has focused primarily on how the brain responds to light rays projected from static images and onto the retina. While this provides a reasonable explanation for the visual perception of a static image, it does not provide an accurate explanation for how we perceive the world as it really is, an ever-changing, and ever-moving 3-D environment. The topics summarized below are representative of this area, but far from exhaustive. To be less topic specific, one can see this textbook for the computational link between neural activities and visual perception and behavior: "Understanding vision: theory, models, and data", published by Oxford University Press 2014.
Biological motion is motion that comes from actions of a biological organism. Humans and animals are able to understand those actions through experience, identification, and higher level neural processing. Humans use biological motion to identify and understand familiar actions, which is involved in the neural processes for empathy, communication, and understanding other's intentions. The neural network for biological motion is highly sensitive to the observer's prior experience with the action's biological motions, allowing for embodied learning. This is related to a research field that is broadly known as embodied cognitive science, along with research on mirror neurons.
Visual perception is the ability to interpret the surrounding environment through photopic vision, color vision, scotopic vision, and mesopic vision, using light in the visible spectrum reflected by objects in the environment. This is different from visual acuity, which refers to how clearly a person sees. A person can have problems with visual perceptual processing even if they have 20/20 vision.
The N170 is a component of the event-related potential (ERP) that reflects the neural processing of faces, familiar objects or words. Furthermore, the N170 is modulated by prediction error processes.
George Malcolm Stratton was an American psychologist who pioneered the study of perception in vision by wearing special glasses which inverted images up and down and left and right. He studied under one of the founders of modern psychology, Wilhelm Wundt, and started one of the first experimental psychology labs in America, at the University of California, Berkeley. Stratton's studies on binocular vision inspired many later studies on the subject. He was one of the initial members of the philosophy department at Berkeley, and the first chair of its psychology department. He also worked on sociology, focusing on international relations and peace. Stratton presided over the American Psychological Association in 1908, and was a member of the National Academy of Sciences. He wrote a book on experimental psychology and its methods and scope; published articles on the studies at his labs on perception, and on reviews of studies in the field; served on several psychological committees during and after World War I; and served as advisor to doctoral students who would go on to head psychology departments.
Prism adaptation is a sensory-motor adaptation that occurs after the visual field has been artificially shifted laterally or vertically. It was first introduced by Hermann von Helmholtz in late 19th-century Germany as supportive evidence for his perceptual learning theory. Since its discovery, prism adaptation has been suggested to improve spatial deficits in patients with unilateral neglect.
In psychology, the face superiority effect refers to the phenomena of how all individuals perceive and encode other human faces in memory. Rather than perceiving and encoding single features of a face, we perceive and encode a human face as one holistic unified element. This phenomenon aids our visual system in the recognition of thousands of faces, a task that would be difficult if it were necessary to recognize sets of individual features and characteristics. However, this effect is limited to perceiving upright faces and does not occur when a face is at an unusual angle, such as when faces are upside-down or contorted in phenomena like the Thatcher effect and Pareidolia.
The face inversion effect is a phenomenon where identifying inverted (upside-down) faces compared to upright faces is much more difficult than doing the same for non-facial objects.