Cognitive practical

• Aim: to partly replicate Peterson and petersons research on trigrams to see if the number of repetitions of a trigram improves recall in short term memory 
• Null hypothesis : there will be no significant difference between the number of repeats of the trigram said allowed (0 or 3) the number of correctly recalled trigrams (0-3)
• Experimental hypothesis: There will be a significant improvement in number of correctly recalled trigrams (0-3) for the 0 repeats condition versus three repeat of the trigram .
• Independent variable: number of repeats of the trigrams (3 letters) said out loud, either 1 or 3.
• Dependant variable: number of correctly recalled trigrams recalled out of min 0 and max 3
• Participant design: repeated measures, in one condition the participant was asked to repeat the trigram once aloud and in the other they repeated the trigrams three times before counting backwards.
• Sample: opportunity sampling via email ; We stated that the experiment was looking at memory to see how we process information to teachers who we knew within school and the venue would be in a classroom in school. 
• Sample description: our sample consisted of 0 male and female teachers of different subjects from our school. We had an equal split of male and female teachers with a range of ages.
• Method of data collection: memory was measured as the number of totally correct trigrams remembers after an 18 second distractor task on a score of 0-3. 

  We recorded what they recalled at the end of the 18 seconds for each other total 6 trails and then scored whether they got it completely correct or not.

  We then calculated the mean, median, mode and standard deviation of our data for Condition A one repeat of trigram and B the 3 repeats of trigram and created a histogram from this as well. We conducted a Wilcoxon statistical test for a difference in condition A and B 
• 1. One experimenter read aloud standardised instructions to the participant, another kept the time of the memory distractor task of 18s and recorded the recall responses of the ppts.
• 2) We conducted two practice trails, one of which they repeated the trigram once before counting backwards in threes and being asked to recall the trigram after 18s of the distractor task and the other of which they repeated a trigram 3 times with the same procedure.
• 3) Then we conducted Condition A 3 trials with trigrams with different letters where they repeated the trigram  once before counting backwards in threes from a given number for 18 seconds and then recalling the trigram
• 4) We then conducted Condition B with 3 trails with trigrams with different letters where they repeated it three times for  before counting backwards in threes from a given number for 18 seconds and then recalling the trigram
• Ethical guidelines:

  To adhered to the ethical guidelines and gave the participants consent forms,  we stated that the experiment was looking at memory to see how we process information and that they had the right to withdraw during or after the experiment.  We kept all of our participants identity anonymous  After the experiment ended we gave our participants a debrief after about the true aim which was to see whether more repetitions would improve memory recall and gave them an email to withdraw their data if they wanted to after the session.
• Quantitative analysis:

  To analyse our quantitive data we worked out the measures of central tendency for the two groups (repeated once) and (repeated twice). We found that the mean number of letters recalled was greater when the participants said the letters once compared to when they said the three letters once. 
• Results: Quantitative results show mean memory for one repetition is 2.14 compared with 2.0 with three or two repetitions but this was not a significant difference.
• Findings were not significant, T value of 7 was not less than or equal to the critical value of 0 for a one tailed test p<0.05 N=5.

  Therefore, there is not a signficant difference in memory recall for trigrams when ppts repeat the trigram once compared with three times prior to a distractor task.
• We were unable to replicate Peterson and Peterson’s research on Trigrams, and concluded that repetition of a trigram does not improve recall in short-term memory.
• This was shown in our results of mean memory for one repetition of  2.14 compared with 2.0 with three  repetitions out of a maximum of 3, but this was not a significant difference.

  n't have a significant effect on the number of total correct syllables recalled. The mean of when syllables were repeated twice/ 
• Therefore, there is not a significant difference in memory recall for trigrams when ppts repeat the trigram once compared with three times prior to a distractor task.
• Strengths/weakness

  1. generalisability The sample included both males and females from different departments of the school teaching faculties, and therefore the sample was representative of both genders and different skills.
• 4male ppts and 3 female ppts were all teachers at SHS. We collected the date in a lab setting, to increase internal validity because  this meant that there was reduced extraneous variables. We shut windows and doors in order to eliminate distractions of sound. All of the ppts were tested in the same room to ensure reliability this meant that the procedure was standardised. The instructions that we gave were standardised since we wrote out a script to read from, was a strength it meant the experiment had good reliability as the procedure was standardised so that our results were consistent. 
• 1. The results lacks generalisability as opportunity sampling was used which means the sample collected is likely to be biased as only certain members of the population (make this specific to our sample - they were only teachers who were working in our school and who had time to attend so not representative of all the teachers) are more likely to have time to participate in a study. As these members usually share similar characteristics, the results  on how repetition improves STM collected are low in generalisability to all teachers at our school and not generalisible to all adults in the UK.
• 1. A weakness of our practical is that it lacks external validity. The experiment was done in a classroom which means that it’s not reflective of a real life environment. This is a weakness because we can’t be sure that memory works the same in a natural environment 
• Improvement

  Using nonsense syllables of three items might be better if vowels were not used. Vowels in the English language tend to make words, or at least three letters that can be seen as a word and pronounced. This might bring in elements of semantic learning (meaning) that were not required in this experiment. 
• Using Trigrams which did not include vowels would mean it is much less likely that participants will use meaning to help recall, increasing internal validity of the results on how rehearsal increases memory.