Peterson and Peterson Short-term Retention of Individual Verbal Items(1959)
Yes we should indeed, Margaret, let's set up in a control area.
Hey Lloyd! We should conduct that experiment that we've been working on.
Margaret and Lloyd Peterson conducted an experiment to investigate the duration of short-term memory as they had seen that other studies have never noted the effect of re-reading or repeating stimuli while they are being learnt on to have the ability to remember later. Therefore,they investigated the effect of varying the opportunity for rehearsal as well as the effect for varying the opportunity for rehearsal.
The Method used was a controlled- lab experiment- Twenty Four psychology students were tested individually
Every student was tested individually. Each student was asked to repeat a set of three letters (triagram) that they heard from the tester. The letters were meaningless consanants, Right after they get told the triagram, they get told a three-digit number by the experimenter, then they need to count backwards in threes or fours from that number.
Then, when a red light turns on, the student had to recall the trigram- eight times with time delays of 3,6,9,12,15 and 18 seconds. This procedure was repeated 48 times using different trigrams. After, a second experiment asked participants to do the same tasks, but some people were given time to repeat the trigram before counting backwards.
They found that the longer the student had to count backwards, the more likely they were not going to remember the trigram. When they were asked to count backwards for three seconds, they remembered over 80% of trigrams correctly, but aftetr 18 seconds, being correct was less than 10%.
In conclusion, the Petersons' found out that information in our short term memory fades quickly and only 10% could be recalled after 18 seconds.