PHOTISM By N., Sam M.S. - 29 noun. 1. a false interpretation or hallucination of light. 2. a type of synesthesia wherein light or color sensations take place in reaction to arousal of other senses. PHOTISM: "The photism you saw was not actually present on the screen." Related Psychology Terms COLOR BLINDNESS SYNESTHESIA (literally, “feeling to- gether”) COLOR SOLID REACTION TIME (Response Latency) LYSERGIC ACID (LSD) COLOR REACTIONS HALLUCINATION PARAMNESIA MUNSELL SYSTEM JUST NOTICEABLE DIFFERENCE (JND; Differential or Difference Threshold) Cite this page: N., Sam M.S., "PHOTISM," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/photism/ (accessed August 10, 2022).