Transcript Does sugar improve the memory of Year 10 students?

Does sugar improve the memory of
Year 10 students?
RESEARCH METHODS IN PSYCHOLOGY
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:
 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.
 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
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.
1.
Memory Test #1
 Get ready...
Memory Test #1
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
ARO
PEL
HIB
ENJ
LOD
ORP
ZIK
NER
CEW
MUP
Memory Test #1
 Participants will have 1 minute to write down the list of 10
words in the correct order.
 Ready, set...
 GO!
Memory Test #1 - Scoring
1.
2.
3.
4.
5.
6.
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8.
9.
10.
ARO
PEL
HIB
ENJ
LOD
ORP
ZIK
NER
CEW
MUP
Memory Test #2
 Get ready...
Memory Test #2
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
WID
GES
NAJ
HOB
MEK
BUP
DOK
TEM
YIS
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.
2.
3.
4.
5.
6.
7.
8.
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10.
WID
GES
NAJ
HOB
MEK
BUP
DOK
TEM
YIS
NIN
Collating of Results
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.
1.
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...
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Memory Test #3
 Get ready...
Memory Test #3
CCG
2. ANZ
3. USA
4. DOC
5. LOL
6. WWW
7. QLD
8. DVD
9. SMS
10. PTO
1.
Memory Test #3
 Participants will have 1 minute to write down the list of 10
words in the correct order.
 Ready, set...
 GO!
Memory Test #3 - Scoring
CCG
2. ANZ
3. USA
4. DOC
5. LOL
6. WWW
7. HIV
8. DVD
9. SMS
10. PTO
1.