- pulsation phenomenon
- The term pulsation phenomenon is indebted to the Latin verb pulsare, which means to hit, to knock, to pulsate. It is used to denote the repeated "magnification or "minification of visually perceived objects. The pulsation phenomenon has been described as a special quality of "macropsia and " micropsia occurring in the context of " migraine aura. The cycle of pulsation (i.e. from the onset of the object's apparent increase or decrease in size until the return to its proper size) tends to be of the order of 10 s. When macrop-tic or microptic vision sets in more gradually, it is referred to as " zoom vision. The pulsation phenomenon has also been described in relation to a recurrent dimness of vision. In the latter case, visually perceived stimuli are gradually replaced by a uniform greyness, to then reappear at a faster pace.ReferencesKlee, A., Willanger, R. (1966). Disturbances of visual perception in migraine. Acta Neurolog-ica Scandinavica, 42, 400-414.
Dictionary of Hallucinations. J.D. Blom. 2010.
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macropsia — Also known as macropsy, macroptic vision, megalopsia, and megalopia. The term macropsia comes from the Greek words makros (large) and opsis (seeing). It refers to a visual distortion in which objects and stimuli are perceived as… … Dictionary of Hallucinations
minification — Also known as perceptual minification. Both terms are indebted to the Latin adjective minimus, which means smallest. They are used to denote the process by which visually perceived objects or stimuli appear to decrease in size. Minification… … Dictionary of Hallucinations
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Oscillator Toda — is special kind of nonlinear oscillator; it is vulgarization of the Toda field theory, which refers to a continuous limit of Toda s chain, of chain of particles, with exponential potential of interaction between neighbors cite journal|… … Wikipedia
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