That scholar was Hermann (*) Ebbinghaus.
Whether a task is completed or uncompleted affects this phenomenon, according to an effect named for a student of Kurt Lewin, Bluma Zeigarnik. One model of this phenomenon was originally a two-stage model, but later incorporated the "sensory" type of this phenomenon; that model was developed by Atkinson and Shiffrin. One scholar studied it using nonsense syllables and came up with an exponential curve representing its decline. That scholar was Hermann (*) Ebbinghaus. The misinformation effect retroactively interferes with this phenomenon, and has been extensively studied by Elizabeth Loftus. One form of it is aided by chunking, and a paper by George Miller cites "seven plus or minus two" as the "magic number" for its "working" variety. For 10 points, name this phenomenon which comes in long-term and short-term varieties.
Whether a task is completed or uncompleted affects this phenomenon, according to an effect named for a student of Kurt Lewin, Bluma Zeigarnik.
memory