Presentation on theme: "RESEARCH METHODS IN PSYCHOLOGY Does sugar improve the memory of Year 10 students?"— Presentation transcript:
RESEARCH METHODS IN PSYCHOLOGY Does sugar improve the memory of Year 10 students?
Research Scenario Dr Starburst is interested in the effect of sugar on the memory of Year 10 students in Victoria. He decides to test the students’ memories by using 2 lists of 10 3-letter nonsense words, which will be presented to participants for one minute. Participants must then recall as many of the 10 nonsense words in each trial as they can. Participants assigned to the experimental group (50%) will consume a quantity of snake lollies prior to participating in the memory test. Participants assigned to the control group will consume no lollies prior to the test. The average scores for each group will be calculated and compared.
Prior Research The impact of increasing blood glucose on psychological functioning: David Benton, Biological Psychology, 1990: The impact of increasing blood glucose on psychological functioning Suggests that “glucose is beneficial when performing tasks demanding little mental capacity”. Carbohydrates and mental function: feeding or impeding the brain?: E. L. Gibson, Nutrition Bulletin, 2007. Carbohydrates and mental function: feeding or impeding the brain? Some people “may benefit from some improvement in mental function after a specific dose of carbohydrate” but “it is too simplistic to assume that ingesting carbohydrates will inevitably improve cognitive function”.
Participants Dr Starburst asks all secondary schools in Victoria if they would like to participate, and twenty schools volunteer. He selects 18 Year 10 students from each school by using a random-number generator on the school rolls, and gets permission from each student’s parents to include them in the study. He then allocates 180 participants to the experimental group and 180 to the control group.
Materials For this study, the following materials will be required: A random number generator or similar device to randomly allocate participants to control or experimental groups Snake lollies for experimental group Two lists of 10 3-letter nonsense words for the memory test Stopwatch or clock for timing Answer sheet for participants to write their answers Spreadsheet or chart for collating results
Hypothesis A Hypothesis is an educated prediction about the outcome of a study or experiment, usually based on prior research. In this case, it may be: “That Year 10 students in Victoria who consume sugar prior to a memory test will have a higher score than Year 10 students who consume no sugar”.
Participant Instructions 1. Participants in the experimental group will consume the allocated quantity of snake lollies prior to the two memory tests. 2. In each test trial, participants must attempt to memorise all ten nonsense words in order. They will be permitted to see the list for 1 minute, before being asked to write the list down in order from memory. They will have 1 minute to recall the full list.
Memory Test #2 1. WID 2. GES 3. NAJ 4. HOB 5. MEK 6. BUP 7. DOK 8. TEM 9. YIS 10. NIN
Memory Test #2 Participants will have 1 minute to write down the list of 10 words in the correct order. Ready, set... GO!
Memory Test #2 - Scoring 1. WID 2. GES 3. NAJ 4. HOB 5. MEK 6. BUP 7. DOK 8. TEM 9. YIS 10. NIN
Collating of Results 1. Participants must add their scores for Test 1 and Test 2 and then divide by 2 to obtain their average or mean score. 2. The scores for all participants in the experimental group must then be collated to obtain a group average 3. The same must be done for the control group. 4. The mean score of each group can then be compared.
Analysing Results / Drawing Conclusions What was the mean score for each group? Was there a small or large difference between the group mean scores? Do you think the difference was significant? Would you conclude that the hypothesis was supported or not supported in this case? What other factors might have influenced the experiment and affected the results? Do you think the overall results can be generalised to the whole population of all students in Victoria?
Research Methods – Key Terminology Type of Study: Experiment Population: Victorian Year 10 students. Sample: 360 Victorian Year 10 students. Participant: A Year 10 Student. Sampling: Random Independent variable (IV): sugar Dependent variable (DV): mean score on memory test Control Group: 180 students who did not consume lollies prior to the tests. Experimental Group: 180 students who did consume lollies prior to the tests. Extraneous Variables: Individual intelligence, mood, what participants may have consumed prior to experiment, etc...