Landry and Bartling (2011)
Uses: working memory model
Aim: to investigate the effect of articulatory suppression on working memory model
Method: true experiment, duel task technique
Procedure:
34 undergrad psychology students
Two groups, experimental group and control group
Experimental group and to say the numbers of 1 and 2 at a rate of two numbers per second (articulatory suppression task), control group did not need to do anything.
Saw ten list of 7 letters series randomly constructed from the letters F,K,L,M,R,X and Q. They are chosen cause they don't sound similar. Presented one letter series at a time. They also received an answer sheet with 7 blanks on them.
Before the experiment, they did a practice to familiarise themselves with the procedure.
Control group shown the printed list for 5 seconds, waited for another 5 seconds, then wrote it down, repeated 10 times.
Experimental group did the same thing but had to say 1 and 2 from the time of presentation of the list until the time they filled the answer sheet, repeated 10 times.
Trails were scored for the accuracy of recall. The trail was scored as correct if the letters were in the correct position. Experimenters calculated the average percent correct recall for both groups.
Result:
Scores from the experimental group was significantly lower than the control group. Mean percent of accurate recall in control group was 76% while experimental group was 45%. The difference in the means were large, the standard deviations were nearly identical with control group having 0.13 and experimental group having 0.14. A t=test was done and found a significant difference of p lower or equal to 0.01 (what does this mean??? What is p test?)
Support the working memory model, articulatory suppression is preventing rehearsal in the phonological loop because of overload. This result in difficulty of remembering letters.
Evaluation:
True experiment, cause and effect, replicable
High internal validity
Lack ecological validity
Small sample size, sampling bias
High construct validity
Landry, P., & Bartling, C.A. The Phonological Loop and Articulatory Suppression.