The "Almost Limitless" Capacity of Recognition Memory

How sensitive is human recognition memory? Standing (1973) tried to find its upper limits. He gave people a single exposure to pictures cut from magazines then tested them in a forced-choice situation using similar pictures as distracters. Standing found that subjects had no difficulty learning 10,000 pictures in one sitting, meaning that they could recognize them the next day and tell them apart from the distracters. He concluded, "The capacity of recognition memory for pictures is almost limitless." In similar research, Shepard (1967) found word recognition was also very accurate-over 90% accurate in forced choice situations.

What did Standing conclude, and how did he arrive at this conclusion?

The excellence of recognition memory creates a potential problem for teachers. A poorly constructed multiple-choice test resembles a forced-choice recognition test. If a teacher puts familiar vocabulary words from the textbook or lecture into the correct alternative, but not into the distracters (false alternatives), then a student can do well on the test simply by picking out words which look familiar without really understanding the principles involved. In fact, students would be foolish not to do this, in such a class, because it produces such good results. Therefore a teacher who constructs tests carelessly, making it easy to pass a test using recognition memory, subverts his or her own goal of encouraging in-depth understanding. No wonder "multiple guess" tests have such a bad reputation among some teachers with high standards.

How can a multiple-choice test be constructed to measure more than recognition?

To produce a multiple-choice test that measures comprehension rather than mere familiarity with terms, a test writer must construct distracters that will trigger a recognition response. All must "sound right" to a student who has merely skimmed rather than studying well. That is easy to accomplish by using familiar words from the text in the wrong answers. Of course, only one answer can be correct, and this should be clear to a student who understands the principle involved. The correct response might not repeat the exact language of the lecture or book. It might use paraphrasing (expressing the same idea in different words). Ideally, a correct understanding of the subject matter, not recognition alone, guides the student to the correct answer. When students consistently receive tests constructed in this way, they learn to do what is necessary; they study hard and learn well, even if their tests are the multiple-choice variety.

Why does your author get impatient with people who "put down" multiple-choice tests?

Constructing tests that require comprehension is not difficult, once one grasps the basic idea. Therefore I get impatient with people who "put down" multiple-choice tests and imply that they automatically produce inferior learning. In my experience, that is not the case. Only poorly constructed multiple-choice tests subvert learning, and teachers should know better than to construct them.


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