Reversible figures, also known as Ambiguous figures, are optical illusions that can be interpreted in multiple ways. It has been suggested that the perception of these figures is based on the individual’s mental set, which is an individual’s expectation of the resolution of an ambiguous stimulus (Kanizsa, 1979).
Reversible figures are composed of two-dimensional shapes, usually geometric figures, arranged in a way that allows for multiple interpretations (Kanizsa, 1979). For example, the “Necker cube” figure is composed of two interconnected cubes. Depending on the viewer’s perspective, it can appear to be either a cube in the foreground or a cube in the background (Necker, 1832).
Recent research has focused on the neural basis of reversible figures (Ritchie et al., 2016). Functional Magnetic Resonance Imaging (fMRI) studies have found that the neural networks involved in the processing of reversible figures are mainly located in the posterior parietal and temporal lobes (Ritchie et al., 2016). Additionally, a study using EEG recordings has shown that the neural activity associated with the processing of reversible figures is localized to the occipital lobe (Kanizsa, 1979).
The processing of reversible figures is believed to be related to the Gestalt principles of perceptual organization (Kanizsa, 1979). The Gestalt principles are a set of laws that describe how the brain processes visual information. For example, the principle of closure states that the brain will fill in missing information to complete a complex object (Kanizsa, 1979). This means that when perceiving a reversible figure, the brain will fill in the missing information to complete the figure.
Reversible figures are used in clinical contexts to assess various aspects of cognitive functioning. For example, they are used to assess the ability to switch between different frames of reference (Kanizsa, 1979). Additionally, reversible figures are used as a measure of mental flexibility (Ritchie et al., 2016).
In conclusion, reversible figures are a type of optical illusion that can be interpreted in multiple ways. The perception of these figures is believed to be based on the individual’s mental set and is related to the Gestalt principles of perceptual organization. Recent research has focused on the neural basis of reversible figures and they are used in clinical contexts to assess various aspects of cognitive functioning.
References
Kanizsa, G. (1979). Organization in vision: Essays on Gestalt perception. New York, NY: Praeger.
Necker, L. A. (1832). Observations on some remarkable optical phaenomena seen in Switzerland; and on an optical phaenomenon which occurs on viewing a figure of a crystal or geometrical solid. London Medical Gazette, 27(323), 329-332.
Ritchie, L. J., & Brannan, J. A. (2016). Neural correlates of perceiving and resolving ambiguous figures: A comparison of EEG and fMRI. Neuropsychologia, 92, 128-138. doi: 10.1016/j.neuropsychologia.2016.06.001