The mean value for the test without a distracter was 14.50 and that of the test with a distracter was 7.81. Therefore more words were remembered without a distracter and the interpretation of this would be that a distracter disrupts short-term memory. The statistical test of choice was the Sign test as the data collected was nominal and the study was a repeated measures investigation. The Sign test gave a result of 0 and the critical value was 3. To be significant the Sign value had to be equal to, or below this critical value and as the Sign value was 0, the experimental hypothesis was accepted and the null hypothesis rejected, suggesting the results were not down to chance and there was cause and effect as to why these results were gained.
Discussion
The aim of the experiment was to determine whether a distracter would affect short-term memory. The experimental hypothesis – use of a distracter will disrupt short-term memory – was accepted, and the null hypothesis – use of a distracter will have no effect on short-term memory – was rejected. The results showed that a distracter significantly affects short-term memory and because of this, the experimental hypothesis has been accepted. The research by the Petersons, and by Glanzer and Cunitz both showed that distracters disrupted short-term memory. The results in this experiment are consistent with that; therefore agree with the results gained by the aforementioned research. A major strength of the methodology of the study was the counterbalancing system implemented. Having half the participants doing the task with the distracter while the others do the task without the distracter, and vice versa, made sure there were no demand characteristics as, the participants had no chance to communicate between tasks.
Another strength of the study was the standardised method used for all participants. Each participant was asked the same things at the same point in the experiment. One of the weaknesses was the sample. The results are not particularly generalisable because there were so few people being tested and all the participants were students aged between sixteen and eighteen, therefore not generalisable to the rest of the population. Students tend to be different from other people as they are generally used to remembering information and many have developed a good ability to do so, whereas much of the rest of the population are not used to doing such things and therefore may not be quite as adept at memorising.
A second weakness is that the study is low in ecological validity. People do not often find themselves in situations where they have a set time to attempt to memorise words and then a set time to recall the remembered words. A further area of research could be to see if the amount of time given to memorise something affects how the efficiency recall. It is possible that having more time to memorise something would improve recall, and ultimately convert short-term memory into long-term memory.