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Summary: From Ebbinghaus to Encoding

Hermann Ebbinghaus began the verbal learning tradition in memory research. His work with nonsense syllables was published in 1885.

Ebbinghaus wanted to study memory of things learned for the first time, uncontaminated by the effects of past experience. His nonsense syllables were intended as new, meaningless stimuli.

Ebbinghaus documented the forgetting curve. It shows rapid loss of information from memory shortly after a retention interval begins, followed by progressively slower rates of forgetting.

This forgetting curve holds true for many types of material. However, one researcher (Linton) found that memory for personal experiences followed more of a straight line, showing a steady loss.

Several well-known techniques are used to test memory. Serial learning requires a subject to learn items in a fixed order.

Free recall allows recall of items in any order. People tend to cluster related items together during recall. This effect occurs whether or not people are instructed to do it.

Cued recall uses prompts to aid memory. It can be used to explore how people encode or interpret a stimulus.

Tests of recognition differ from tests of recall. The subject is presented with an item and asked if it is familiar from earlier in the experiment.

The yes/no method is less accurate than the forced choice method. If asked for a yes or no recognition judgment, people differ in the level of confidence required for saying Yes.

Forced choice testing removes the effects of Yes/No response bias. Partly because it forces people to make a choice even if they are uncertain, it is a sensitive test of recognition memory.

Pictures can be used as stimuli in forced-choice tests of recognition memory. Such research shows an "almost limitless" capacity to recognize distinct patterns in both humans and non-human animals.

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