Effect of Monday-Thursday Fasting on Cognitive Function of Teenager
EFFECT OF MONDAY-THURSDAY FASTING
ON COGNITIVE FUNCTION OF TEENAGER
RAJA ARIA OCTIVANO
G34103041
DEPARTMENT OF BIOLOGY
FACULTY OF MATHEMATIC AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY
2008
ABSTRACT
RAJA ARIA OCTIVANO. Effect of Monday-Thursday Fasting on Cognitive Function of Teenager.
Supervised by BAMBANG SURYOBROTO and AKICHIKA MIKAMI.
Cognitive function consists many aspects, one of them is memory. Memory is a complex
cognitive function that allows the recording, maintenance, and utilization of new information. Memory
can be distinguished into two types: short-term memory and long-term memory. One part of short-term
memory is the working memory. All the function takes place in human brain which requires large
amount of energy which came from glucose degradation of daily food. A recent study shows there is
no effect of fasting on cognitive function of university student, but there is no current data about
teenager. So, the objective of this research is to find whether fasting influences performance on
memory task of teenager. Sequential Probe Delayed Matching to Sample (SPDMS) task was selected
as a memory task, which subjects was ordered to perform a test in two conditions: fasting and no
fasting. Data was analyzed by ANOVA implemented in R statistical program. The result shows that
fasting affected working memory task. Task performances got better under fasting condition, possibly
because the effect of stress on subjects performances. There were also influences from sex difference
due to male’s brain advantage in spatial skill which is necessary for SPDMS task. Learning process
from previous session also gave influence, but the effect was small. It is due to the efficiency of human
brain to study about new information. In conclusion, fasting was the main factor influencing working
memory task, while session and sex difference gave only small.
ABSTRAK
RAJA ARIA OCTIVANO. Efek dari Puasa Senin-Kamis terhadap Fungsi Kognitif Remaja.
Dibimbing oleh BAMBANG SURYOBROTO dan AKICHIKA MIKAMI.
Fungsi kognitif terdiri dari banyak aspek, salah satunya adalah memori. Memori adalah fungsi
kognitif yang kompleks yang memungkin penyimpanan, pengolahan, dan pemanfaatan informasi.
Berdasarkan kapasitas penyimpanannya, memori dibagi menjadi dua jenis: memori jangka pendek dan
memori jangka panjang. Salah satu jenis memori jangka pendek adalah memori bekerja. Fungsi ini
terjadi di otak manusia yang membutuhkan energi dalam jumlah besar dari degradasi glukosa makanan
sehari-hari. Studi terakhir menyatakan tidak ada efek puasa pada fungsi kognitif mahasiswa, namun
untuk remaja belum diketahui. Maka, tujuan penelitian ini untuk mengetahui apakah puasa
mempengaruhi kemampuan kerja memori remaja. SPDMS dipilih sebagai kerja memori, dimana
subjek diminta untuk melakukan percobaan dalam dua kondisi: Puasa dan tidak puasa. Data dianalisa
menggunakan ANOVA dalam program statistik R. Hasil analisa menunjukkan bahwa puasa
mempengaruhi memori kerja. Kemampuan kerja meningkat pada kondisi puasa dikarenakan puasa
memberikan tingkat stress optimal yang dapat meningkatkan kinerja. Jenis kelamin juga menunjukkan
perbedaan hasil disebabkan oleh kemampuan otak laki-laki yang lebih baik dalam kemampuan spasial,
yang sangat diperlukan dalam tes SPDMS. Proses belajar juga berpengaruh, namun sedikit. Hal ini
disebabkan oleh kemampuan otak manusia untuk belajar secara efisien mengenai informasi baru.
Kesimpulan yang didapat adalah puasa merupakan faktor utama yang mempengaruhi kerja memori,
sedangkan sesi dan jenis kelamin hanya memberi sedikit pengaruh.
EFFECT OF MONDAY-THURSDAY FASTING
ON COGNITIVE FUNCTION OF TEENAGER
Raja Aria Octivano
G3413041
Minithesis
To obtain Bachelor’s of Science
In
Department of Biology
DEPARTMENT OF BIOLOGY
FACULTY OF MATHEMATIC AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY
2008
Title : Effect of Monday-Thursday Fasting on Cognitive Function of Teenager
Name : Raja Aria Octivano
NRP : G34103041
Approved:
Advisor 1
Advisor 2
Dr. Bambang Suryobroto
NIP 131779503
Prof. Dr. Akichika Mikami
Endorsed by:
Dean Faculty of Mathematic and Natural Sciences
Bogor Agricultural University
Dr. drh. Hasim, DEA.
NIP 131578806
Graduation Date:
FOREWORD
Praise the God for all kindness and benevolence, this minithesis is finally done.
People usually think fasting is a kind of activity that limits your body. Especially for people
who think if you don’t eat, you will have no power for your activity. Is this kind of think true? What
about Muslim people who perform fasting regularly? That is the purpose of this research, to find
whether fasting is truly a bad activity for your body, or the opposite, brings a good effect for you.
Writer acknowledgments send to Dr. Bambang Suryobroto and Prof. Dr. Akichika Mikami, MD
as writer’s advisors. Also deepest gratitude to Dra. Taruni Sri Prawasti, Dr.Ir. Achmad Farajallah,
M.Si, Dr. Ir. Diah Perwitasari, M.Si, Dr. Ir. Rika Raffiudin, M.Si, Ir. Tri Heru, M.Si, Ir. Tri Atmowidi,
M.si and all staff in Zoology laboratory for the support and kindness. To all my friends in Biology 40
who gave motivation and friendship. To Mr. Solay for all of your kindness, and all of my subjects for
their participation and motivation. Writer’s acknowledgment especially send to Parent and my lovely
“Queen” for their love, support, kindness, motivation, and their pray.
Hopefully, this minithesis could be useful.
Bogor, April 2008
RAJA ARIA OCTIVANO
CURRICULUM VITAE
Writer was born in Jakarta on 11th October 1985 as the first child from parent, Djoko Hadi
Tjiptanto and Ramayulis.
On 2003, writer graduated from SMU Labschool Rawamangun, Jakarta and entered the
Department of Biology, Faculty of Mathematic and Natural Sciences, Bogor Agricultural University
via ‘Undangan Saringan Masuk IPB’ (USMI).
On 2005, writer did field study at Situ Gunung, Sukabumi with “Effect of Light to Sellaginella
Leaf Surface” as a title and related topic. Writer also did field work on 2006 at Taman Safari Indonesia
Cisarua, Bogor with “Ex-Situ Conservation of Sumatran Tiger (Panthera tigris sumatrae) at Taman
Safari Indonesia” as a title. On 2007 writers become assistant in practical class of Basic Biology,
Animal Developing, and Animal Physiology.
.
CONTENTS
Page
LIST OF FIGURES ………………….………………………………………………………. .
VIII
LIST OF TABLES …………………………………………………………………………….
VIII
LIST OF APPENDIX ………………………………………………………….……………..
VIII
INTRODUCTION …………………………………………………………………………….
MATERIAL AND METHODS ...…………………………………………………………….
Method …………………………… ……………………………………………….……..
Procedures ……………………………………………………………………………..….
Statistical Analytic …………………………………………………………..……….……
1
1
1
2
2
RESULT …………………………………………………………………………….………...
Blood Glucose Level Measured…………………………………………………………….
Highest Level Achieved ……………………………………………………………...…….
Performance Achieved .…………………………………………………………………….
Reaction Time Attained ………………………………………………………………….
2
2
2
3
3
DISCUSSION ..…………………………………………………..……………….…………….
4
CONCLUSION …........................................................................................................................
4
REFERENCES…………………………………………………………………….…...………..
4
Appendix ………………………………………..……………………………….…………….
5
LIST OF FIGURES
Page
1 Scheme structures and procedures of DMTS task………..………………………………………
1
2 Model of experiment...……………………………………………………………………………
2
3 Highest level achieved during fasting condition………………………………………………….
2
4 Performance achieved from the 1st to 2nd session…………………………………………………
3
5 Performance achieved during fasting condition……….…………………………………………..
3
6 Reaction time attained during fasting condition…………………………………………………… 3
LIST OF APPENDIX
Page
1 ANOVA tables of highest level achieved………………………….………………………………
6
2 ANOVA tables of highest level achieved………………………….………………………………
7
3 ANOVA tables of highest level achieved………………………….……………………………… 8
4 Subject data………………………………………………………………………………………...
9
1
INTRODUCTION
Background
Cognitive function consists of many aspects,
such as perception, learning, memory, reasoning,
and speech (human) (Redmond 2006). It distincts
from emotion and volition. Memory is a complex
cognitive function that allows the recording,
maintenance, and utilization of new information
(Thompson 2005). Construction of memory
consists of two separate stages: encoding and
retrieval. Encoding refers to initial process of
information that will potentially be stored as
memory episodes. Retrieval refers to process
that result from the encoded episodes (Buckner
1998). Based on the storage capacity, memory
can be distinguished into two types: short-term
and long-term systems. Short-term memory has a
limited capacity and memory trace can
spontaneously fade within seconds, while the
long-term one has massive capacity and
durability (Baddeley 1996).
One kind of short-term memory is the
working memory. Working memory is the ability
to hold an item of information transiently in
mind in the service of comprehension, thinking,
and planning. It serves as a workspace for
holding items and information in mind as they
are recalled, manipulated, and / or associated to
other ideas and incoming information (Goldman
1996).
Cognitive function is processed in brain.
Brain is only a small part of our body, but
consumes large amount of energy. It uses about
20% of total body energy in order to perform
cognitive and other tasks. This energy comes
from glucose degradation (Benton 1998). The
brain uses glucose almost exclusively for its
energy needs and requires continual supply of
this sugar for normal function (Frissel 1990). An
overnight and morning fast could lower the brain
function such as has been shown for the lowering
of memory process and attention level of school
children (Pollit 1998). On the opposite, there is
evidence that short-term food deprivation has
little or no effect on cognitive function (Green
1995). The deficits of cognitive function
associated with spontaneous dieting are not due
to any direct physiological or nutritional effect.
Instead, psychological effect of this condition
might be more important.
Monday-Thursday fasting (MTFast) is a
religious and cultural fasting that is performed by
Indonesian people, including teenagers. MTFast
provides a model of how caloric restriction
influences performance on memory task.
Erlangga (2006) showed that visual and spatial
working memory of university students didn’t
affected by this kind of fasting. All of the
subjects had study experience for 14 years or
more, so generally they are highly intelligence.
In average, they could reach high performance
on working memory task. Both sex (male and
female) had a same performance on memory
task. On the other hand, learning process was
found as a primary factor influencing the
memory task performance. Currently there is no
data for memory task performance of younger
people, such as teenager in junior high school. In
this research, I will show you the positive effect
of MTFast on working memory of teenager.
Objective
To find whether MTFast influences
performance on memory task of teenager.
MATERIAL AND METHODS
Place and Time
Research was done from March 2007 until
February 2008. Primary data collection was
taken at junior high schools in Jakarta. Data
analysis was done at Section of Biosysthematics
and Ecology of Animals, Department of Biology,
Faculty of Mathematics and Nature Sciences
Bogor Agricultural University.
Method
Working
memory
involves
spatial,
phonological and somatosensory memories
(Baddeley 1996). In this research, visual and
spatial memories are the primary basic for
Sequential Probe Delayed Matching to Sample
(SPDMS) task. This task means the subject must
choose the right stimulus, on the right order,
after a short delay (Elliot 1999). Stimuli were
presented as pictures of irregular shapes. The
scheme of SPDMS task can be seen in Figure 1.
1500ms
blank
1500ms
stimulus 1
1500ms
blank
1050ms
indicator
l
F) of fasting is 0.75 % and
interaction of fasting and glucose is 9.4 % which
is below 10% (see Appendix 1). This value
indicates that fasting and glucose had the highest
possibility of affecting the highest level
achieved.
If we abandon sex and session, and retaining
fasting and glucose value, we got fasting as the
main factor affecting highest level achieved.
However, comparison of both models show that
they explained the data similarly (Appendix 1),
so we may chose model 2 as the simpler one for
further discussion.
Performance Achieved
Figure 4 and 5 show an increasing mean of
performance according to sessions and
conditions.
Both factors were affecting performance
achieved.
The result of ANOVA between factors that
possibly affecting performance achieved shows
that the value of Pr(>F) of fasting is 0.13%
which is below 5% (see Appendix 2). This value
indicates that fasting had the highest possibility
to affect performance achieved.
If we abandon session, sex and glucose, and
retaining fasting value, indeed we got fasting and
session as the main factor affecting highest level
achieved. Comparison showed that both model
explained the data similarly (Appendix 2), so we
may chose model 2 as the simpler one for further
discussion.
Reaction Time
Figure 6 shows a decreasing mean of
reaction time during fasting condition for male.
Note there is a different slope for each sex. This
means that the way male and female reacts under
fasting or no fasting condition were different.
The result of ANOVA between factors that
possibly affecting reaction time shows that the
value of Pr(>F) of sex is 1.34% and fasting is
5.56%, and the value of sex and fasting
interaction is 7.8% which is below 10% (see
Appendix 3). This value indicates that sex and
fasting had the highest possibility of affecting
reaction time.
If we abandon session and glucose, and
retaining fasting and sex value, indeed we got
fasting as the main factor affecting reaction time.
There was also a difference between male and
female on reaction time attained. Comparison
showed both model may explained the data
similarly (Appendix 3), so we may chose model
2 as the simpler one for further discussion.
Figure 4. Performance achieved from the 1st to
2nd session.
Figure 5. Performance achieved during fasting
condition.
Figure 6. Reaction time attained during fasting
condition.
4
In summary, result shows that there were
significant effects of fasting on working memory
task. Highest level achieved, performance
achieved, and reaction time were affected by
fasting condition. Session gave a small effect in
performance, and sex also showed a small
difference between male and female reaction
time.
DISCUSSION
Glucose is the main metabolite of brain and
working muscle. Homeostasis system in human
body performs metabolic adaptation to maintain
blood glucose level as constant as possible.
During starvation, glucose will be synthesized
from the glycerol product of triacylglycerol
breakdown and the amino acids from the
proteolytic degradation of proteins. Muscle is the
major source for these materials. Measurements
of peripheral blood glucose level in no fasting
and fasting condition showed only small
degradation that was still in a normal range. We
may safely assume that glucose level in brain
also in normal range. However, fasting is a form
of stress in human.
Some study showed that human works better
under certain psychological stress conditions
(Bourne 2003). Besides, without any supply of
food, digestion system will suspend their activity
so they don’t require energy. This energy can be
shifted to other system such as the neural system.
Present research shows that, under the
circumstances that nutrition level was not
harmed, subjects achieved higher working
memory performance while in fasting condition.
Performances of working memory task were
increased. They were shown by higher level
achieved, influencing better performance
attained for all subjects, and shorter reaction time
for male.
Male had a significantly shorter reaction
time under fasting condition, while female did
not. This result came from the different way of
male and female’s brain work. Male’s brain has
better spatial ability than female (Pease 2001).
Spatial skill is necessary in SPDMS task because
the target objects appears in random position.
Session gave small influence in working
memory task. Performance got better on the 2nd
session, as a result of learning process carried
over from the 1st session, so they became
familiar and more efficient while doing the task.
Previous study (Erlangga 2006) also showed that
learning process was carried over affecting
working memory task. So, from these facts we
found that human brain is easy and efficient for
learning new information.
CONCLUSION
Fasting influences teenager’s visual and
spatial memory task although learning process
and sex difference modulate this effect.
REFERENCES
Baddeley A. 1996. The fractionation of working
memory. Proc Natl Acad Sci 9:1346813472.
Benton D, Parker PY. 1998. Breakfasts, blood
glucose, and cognition. Am J Clin Nutr
67:772-781.
Bourne LE, Yaroush RA. 2003. Stress and
cognition: a cognitive psychological
perspective. USA: NASA
Buckner RL, Koutstaal W. 1998. Functional
neuroimaging studies of encoding, priming,
and explicit memory retrieval. Proc Natl
Acd Sci. 95: 891-898.
Elliot R. 1999. Differential neural responses
during performance of matching and
nonmatching to sample tasks at two delay
intervals. J Neuroscience 19(12):5066–
5073.
Erlangga D. 2006. Effect of Monday-Thursday
fasting on cognitive function. Bogor: IPB
Frissel WR. 1990. Human Biochemistry. USA:
Macmillan Publishing Co Inc.
Goldman PS. 1996. Regional and cellular
fractionation of working memory. Proc Natl
Acad Sci. 93:13473-13480.
Green MW, Elliman NA, Rogers PJ. 1995. Lack
of effect of short-term fasting on cognitive
function. J Psychiat Res 29(3): 245 253,
Pease B, Pease A. 2001. Why men don’t listen
and women can’t read maps. Great Britain:
Orion Publishing Group.
Pollit E, Jacoby E. 1998. Fasting and cognition
in well and undernourished school children.
Am J Clin Nutr 67:779-812.
Redmond WA. 2006. Cognition. Microsoft
Encarta [DVD]. Microsoft Corporation,
2005.
Thompson F, Madigan SA. 2005. Memory: The
Key to Consciousness. Washington DC:
Joseph Henry Press.
5
APPENDIX
6
Appendix 1. ANOVA tables of highest level achieved.
Model 1. ANOVA result of how fasting, sex, session and glucose influence to highest level achieved.
Sex
Fasting
Session
Glucose
Sex : Fasting
Fasting : Session
Sex : Glucose
Fasting : Glucose
Session : Glucose
Sex : Fasting : Glucose
Df
1
1
1
4
1
1
4
4
1
2
Sum Sq.
0.150
12.150
0.171
2.161
0.141
1.363
3.162
13.077
0.218
0.923
Mean Sq.
0.150
12.150
0.171
0.540
0.141
1.363
0.791
3.269
0.218
0.462
Residuals
39
59.467
1.525
F value
0.0984
7.9683
0.1124
0.3543
0.0927
0.8941
0.5185
2.1441
0.1427
0.3027
Pr (>F)
75.55% NS
0.75% *
73.92% NS
83.95% NS
76.23% NS
35% NS
72.26% NS
9.4% *
70.77% NS
74% NS
Model 2. ANOVA result of fasting and glucose factors to highest level achieved.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Fasting
Glucose
Fasting : Glucose
1
4
4
12.150
2.245
11.022
12.150
0.561
2.755
8.911
0.4153
2.0391
0.42% *
79.68% NS
10.3% NS
Residuals
50
67.567
1.351
Comparison of each statistic models.
Model 1: Level ~ Sex * Fasting * Session * Glucose
Model 2: Level ~ Fasting * Glucose
Res. Df
39
50
RSS
59.467
67.567
Df
Sum of Sq
F
Pr(>F)
-11
-8.100
0.4829
90.3% NS
7
Appendix 2. ANOVA tables of performance attained.
Model 1. ANOVA result of how fasting, sex, session and glucose influence to performance achieved.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Sex
Fasting
Session
Glucose
Sex : Fasting
Fasting : Session
Sex : Glucose
Fasting : Glucose
Session : Glucose
Sex : Fasting : Glucose
1
1
1
4
1
1
4
4
1
2
134.4
2176.8
401.0
112.7
41.1
171.3
437.9
1186.5
157.5
46.2
134.4
2176.8
401.0
28.2
41.1
171.3
109.5
296.6
157.5
23.1
0.7426
12.0277
2.2158
0.1557
0.2268
0.9464
0.6049
1.6389
0.8704
0.1278
39.4% NS
0.13% *
14.5% NS
95.9% NS
63.6% NS
33.7% NS
66.1% NS
18.4% NS
35.7% NS
88% NS
Residuals
39
7058.4
181
Model 2. ANOVA result of fasting factors to performance achieved.
Fasting
Residuals
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
1
58
2176.8
9747.1
2176.8
168.1
12.953
0.06% *
Comparison of each statistic models
Model 1: Performance8 ~ Sex * Fasting * Session * Glucose
Model 2: Performance8 ~ Fasting
Res.Df
39
58
RSS
7058.4
9747.1
Df
Sum of Sq
F
Pr(>F)
-19
-2688.7
1.131
71.3% NS
8
Appendix 3. ANOVA tables of reaction time attained.
Model 1. ANOVA result of how fasting, sex, session and glucose influence to reaction time attained.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Sex
Fasting
Session
Glucose
Sex : Fasting
1
1
1
4
1
189282
109739
35503
81659
91786
189282
109739
35503
20415
91786
6.7153
3.8933
1.2596
0.7243
3.2564
1.34% *
5.56% *
26.86% NS
58.1% NS
7.8% *
Fasting : Session
1
1847
1847
0.0655
79.93% NS
Sex : Glucose
4
64740
16185
0.5742
68.3% NS
Fasting : Glucose
4
136351
34088
1.2094
32.24% NS
Session : Glucose
1
15457
15457
0.5484
46.34% NS
Sex : Fasting : Glucose 2
28697
14349
0.5091
60.5% NS
Residuals
1099278
28187
39
Table 6. ANOVA result of sex and fasting to reaction time attained.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Fasting
Sex
Fasting : Sex
1
1
1
109739
189282
149401
109739
189282
149401
4.3711
7.5394
5.9509
4.1% *
0.8% *
1.8% *
Residuals
56
1405917
25106
Analysis of Variance Table
Model 1: Reaction ~ Sex * Fasting * Session * Glucose
Model 2: Reaction ~ Fasting * Sex
Res.Df
39
56
RSS
1099278
1405917
Df
Sum of Sq
F
Pr(>F)
-17
-306640
0.6399
83.8% NS
9
Appendix 4. Subject data
Name
A
A
B
B
C
C
D
D
E
E
F
F
G
G
H
H
I
I
J
J
K
K
L
L
M
M
N
N
O
O
O
O
P
P
Q
Q
R
R
S
S
T
T
U
U
V
V
W
W
X
X
Y
Sex
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
Fasting
yes
no
yes
no
yes
no
yes
no
no
yes
yes
no
no
yes
yes
no
no
yes
no
yes
yes
no
yes
no
no
yes
yes
no
yes
no
yes
no
yes
no
yes
no
no
yes
yes
no
no
yes
no
yes
no
yes
no
yes
yes
no
no
Session
2
1
2
1
2
1
2
1
1
2
2
1
1
2
2
1
1
2
1
2
2
1
2
1
1
2
2
1
2
1
2
1
2
1
2
1
2
1
1
2
1
2
1
2
1
2
1
2
2
1
1
Glucose
B
E
A
B
B
B
E
C
C
B
D
D
B
C
B
B
C
B
D
A
A
D
D
D
B
B
A
E
C
C
B
B
B
D
A
C
C
B
B
D
C
B
B
D
C
C
B
A
D
E
C
Level
3
3
5
5
6
5
5
5
2
4
4
3
5
6
4
3
3
5
2
2
6
5
5
4
3
2
4
3
3
1
4
3
5
4
3
3
3
4
3
3
3
5
5
5
2
6
3
5
5
5
3
Performance
70.30
56.30
81.30
60.40
89.80
76.70
69.10
75.70
66.90
52.10
71.10
65.60
46.90
75.40
68.60
55.20
59.90
75.30
61.20
64.70
75.10
67.70
69.40
52.90
70.30
53.20
85.10
67.70
53.60
82.10
64.90
62.50
67.00
56.20
64.60
61.50
88.50
48.80
50.50
53.60
70.30
75.30
50.30
78.80
74.80
72.40
50.50
75.30
87.80
59.00
59.40
Performance8
34.10
27.30
59.10
43.90
75.50
55.80
50.30
55.10
23.50
31.80
43.40
31.80
34.10
63.40
41.90
26.80
29.00
54.80
21.50
22.90
63.10
49.20
50.50
32.30
34.10
18.70
52.00
32.80
26.00
17.40
39.60
30.30
48.70
34.30
31.30
21.80
42.90
29.80
24.50
26.00
34.10
54.80
30.60
57.30
26.30
60.90
24.50
54.80
63.90
42.90
28.80
Reaction
1261
1640
1226
1467
1405
1513
1314
1637
1204
1062
1297
1539
1318
1440
1466
1594
1566
1505
1629
1448
1572
1977
1569
1528
1696
1329
1384
1531
1501
1720
1454
1384
1431
1356
1127
1367
1168
1356
1448
1443
1447
1449
1280
1467
1275
1536
1323
1506
1223
1291
1538
10
Y
Z
Z
AA
AA
AB
AB
AC
AC
F
F
F
F
F
F
F
F
F
yes
no
yes
no
yes
no
yes
yes
no
2
1
2
1
2
1
2
2
1
D
B
A
B
A
C
B
C
A
4
2
2
3
5
2
3
5
5
62.80
66.20
63.30
52.60
59.00
59.70
53.60
76.00
68.40
38.40
23.20
22.20
25.50
42.90
21.00
26.00
55.30
49.70
1458
1566
1332
1615
1597
1291
1195
1012
1033
EFFECT OF MONDAY-THURSDAY FASTING
ON COGNITIVE FUNCTION OF TEENAGER
RAJA ARIA OCTIVANO
G34103041
DEPARTMENT OF BIOLOGY
FACULTY OF MATHEMATIC AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY
2008
ABSTRACT
RAJA ARIA OCTIVANO. Effect of Monday-Thursday Fasting on Cognitive Function of Teenager.
Supervised by BAMBANG SURYOBROTO and AKICHIKA MIKAMI.
Cognitive function consists many aspects, one of them is memory. Memory is a complex
cognitive function that allows the recording, maintenance, and utilization of new information. Memory
can be distinguished into two types: short-term memory and long-term memory. One part of short-term
memory is the working memory. All the function takes place in human brain which requires large
amount of energy which came from glucose degradation of daily food. A recent study shows there is
no effect of fasting on cognitive function of university student, but there is no current data about
teenager. So, the objective of this research is to find whether fasting influences performance on
memory task of teenager. Sequential Probe Delayed Matching to Sample (SPDMS) task was selected
as a memory task, which subjects was ordered to perform a test in two conditions: fasting and no
fasting. Data was analyzed by ANOVA implemented in R statistical program. The result shows that
fasting affected working memory task. Task performances got better under fasting condition, possibly
because the effect of stress on subjects performances. There were also influences from sex difference
due to male’s brain advantage in spatial skill which is necessary for SPDMS task. Learning process
from previous session also gave influence, but the effect was small. It is due to the efficiency of human
brain to study about new information. In conclusion, fasting was the main factor influencing working
memory task, while session and sex difference gave only small.
ABSTRAK
RAJA ARIA OCTIVANO. Efek dari Puasa Senin-Kamis terhadap Fungsi Kognitif Remaja.
Dibimbing oleh BAMBANG SURYOBROTO dan AKICHIKA MIKAMI.
Fungsi kognitif terdiri dari banyak aspek, salah satunya adalah memori. Memori adalah fungsi
kognitif yang kompleks yang memungkin penyimpanan, pengolahan, dan pemanfaatan informasi.
Berdasarkan kapasitas penyimpanannya, memori dibagi menjadi dua jenis: memori jangka pendek dan
memori jangka panjang. Salah satu jenis memori jangka pendek adalah memori bekerja. Fungsi ini
terjadi di otak manusia yang membutuhkan energi dalam jumlah besar dari degradasi glukosa makanan
sehari-hari. Studi terakhir menyatakan tidak ada efek puasa pada fungsi kognitif mahasiswa, namun
untuk remaja belum diketahui. Maka, tujuan penelitian ini untuk mengetahui apakah puasa
mempengaruhi kemampuan kerja memori remaja. SPDMS dipilih sebagai kerja memori, dimana
subjek diminta untuk melakukan percobaan dalam dua kondisi: Puasa dan tidak puasa. Data dianalisa
menggunakan ANOVA dalam program statistik R. Hasil analisa menunjukkan bahwa puasa
mempengaruhi memori kerja. Kemampuan kerja meningkat pada kondisi puasa dikarenakan puasa
memberikan tingkat stress optimal yang dapat meningkatkan kinerja. Jenis kelamin juga menunjukkan
perbedaan hasil disebabkan oleh kemampuan otak laki-laki yang lebih baik dalam kemampuan spasial,
yang sangat diperlukan dalam tes SPDMS. Proses belajar juga berpengaruh, namun sedikit. Hal ini
disebabkan oleh kemampuan otak manusia untuk belajar secara efisien mengenai informasi baru.
Kesimpulan yang didapat adalah puasa merupakan faktor utama yang mempengaruhi kerja memori,
sedangkan sesi dan jenis kelamin hanya memberi sedikit pengaruh.
1
INTRODUCTION
Background
Cognitive function consists of many aspects,
such as perception, learning, memory, reasoning,
and speech (human) (Redmond 2006). It distincts
from emotion and volition. Memory is a complex
cognitive function that allows the recording,
maintenance, and utilization of new information
(Thompson 2005). Construction of memory
consists of two separate stages: encoding and
retrieval. Encoding refers to initial process of
information that will potentially be stored as
memory episodes. Retrieval refers to process
that result from the encoded episodes (Buckner
1998). Based on the storage capacity, memory
can be distinguished into two types: short-term
and long-term systems. Short-term memory has a
limited capacity and memory trace can
spontaneously fade within seconds, while the
long-term one has massive capacity and
durability (Baddeley 1996).
One kind of short-term memory is the
working memory. Working memory is the ability
to hold an item of information transiently in
mind in the service of comprehension, thinking,
and planning. It serves as a workspace for
holding items and information in mind as they
are recalled, manipulated, and / or associated to
other ideas and incoming information (Goldman
1996).
Cognitive function is processed in brain.
Brain is only a small part of our body, but
consumes large amount of energy. It uses about
20% of total body energy in order to perform
cognitive and other tasks. This energy comes
from glucose degradation (Benton 1998). The
brain uses glucose almost exclusively for its
energy needs and requires continual supply of
this sugar for normal function (Frissel 1990). An
overnight and morning fast could lower the brain
function such as has been shown for the lowering
of memory process and attention level of school
children (Pollit 1998). On the opposite, there is
evidence that short-term food deprivation has
little or no effect on cognitive function (Green
1995). The deficits of cognitive function
associated with spontaneous dieting are not due
to any direct physiological or nutritional effect.
Instead, psychological effect of this condition
might be more important.
Monday-Thursday fasting (MTFast) is a
religious and cultural fasting that is performed by
Indonesian people, including teenagers. MTFast
provides a model of how caloric restriction
influences performance on memory task.
Erlangga (2006) showed that visual and spatial
working memory of university students didn’t
affected by this kind of fasting. All of the
subjects had study experience for 14 years or
more, so generally they are highly intelligence.
In average, they could reach high performance
on working memory task. Both sex (male and
female) had a same performance on memory
task. On the other hand, learning process was
found as a primary factor influencing the
memory task performance. Currently there is no
data for memory task performance of younger
people, such as teenager in junior high school. In
this research, I will show you the positive effect
of MTFast on working memory of teenager.
Objective
To find whether MTFast influences
performance on memory task of teenager.
MATERIAL AND METHODS
Place and Time
Research was done from March 2007 until
February 2008. Primary data collection was
taken at junior high schools in Jakarta. Data
analysis was done at Section of Biosysthematics
and Ecology of Animals, Department of Biology,
Faculty of Mathematics and Nature Sciences
Bogor Agricultural University.
Method
Working
memory
involves
spatial,
phonological and somatosensory memories
(Baddeley 1996). In this research, visual and
spatial memories are the primary basic for
Sequential Probe Delayed Matching to Sample
(SPDMS) task. This task means the subject must
choose the right stimulus, on the right order,
after a short delay (Elliot 1999). Stimuli were
presented as pictures of irregular shapes. The
scheme of SPDMS task can be seen in Figure 1.
1500ms
blank
1500ms
stimulus 1
1500ms
blank
1050ms
indicator
l
F) of fasting is 0.13%
which is below 5% (see Appendix 2). This value
indicates that fasting had the highest possibility
to affect performance achieved.
If we abandon session, sex and glucose, and
retaining fasting value, indeed we got fasting and
session as the main factor affecting highest level
achieved. Comparison showed that both model
explained the data similarly (Appendix 2), so we
may chose model 2 as the simpler one for further
discussion.
Reaction Time
Figure 6 shows a decreasing mean of
reaction time during fasting condition for male.
Note there is a different slope for each sex. This
means that the way male and female reacts under
fasting or no fasting condition were different.
The result of ANOVA between factors that
possibly affecting reaction time shows that the
value of Pr(>F) of sex is 1.34% and fasting is
5.56%, and the value of sex and fasting
interaction is 7.8% which is below 10% (see
Appendix 3). This value indicates that sex and
fasting had the highest possibility of affecting
reaction time.
If we abandon session and glucose, and
retain
ON COGNITIVE FUNCTION OF TEENAGER
RAJA ARIA OCTIVANO
G34103041
DEPARTMENT OF BIOLOGY
FACULTY OF MATHEMATIC AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY
2008
ABSTRACT
RAJA ARIA OCTIVANO. Effect of Monday-Thursday Fasting on Cognitive Function of Teenager.
Supervised by BAMBANG SURYOBROTO and AKICHIKA MIKAMI.
Cognitive function consists many aspects, one of them is memory. Memory is a complex
cognitive function that allows the recording, maintenance, and utilization of new information. Memory
can be distinguished into two types: short-term memory and long-term memory. One part of short-term
memory is the working memory. All the function takes place in human brain which requires large
amount of energy which came from glucose degradation of daily food. A recent study shows there is
no effect of fasting on cognitive function of university student, but there is no current data about
teenager. So, the objective of this research is to find whether fasting influences performance on
memory task of teenager. Sequential Probe Delayed Matching to Sample (SPDMS) task was selected
as a memory task, which subjects was ordered to perform a test in two conditions: fasting and no
fasting. Data was analyzed by ANOVA implemented in R statistical program. The result shows that
fasting affected working memory task. Task performances got better under fasting condition, possibly
because the effect of stress on subjects performances. There were also influences from sex difference
due to male’s brain advantage in spatial skill which is necessary for SPDMS task. Learning process
from previous session also gave influence, but the effect was small. It is due to the efficiency of human
brain to study about new information. In conclusion, fasting was the main factor influencing working
memory task, while session and sex difference gave only small.
ABSTRAK
RAJA ARIA OCTIVANO. Efek dari Puasa Senin-Kamis terhadap Fungsi Kognitif Remaja.
Dibimbing oleh BAMBANG SURYOBROTO dan AKICHIKA MIKAMI.
Fungsi kognitif terdiri dari banyak aspek, salah satunya adalah memori. Memori adalah fungsi
kognitif yang kompleks yang memungkin penyimpanan, pengolahan, dan pemanfaatan informasi.
Berdasarkan kapasitas penyimpanannya, memori dibagi menjadi dua jenis: memori jangka pendek dan
memori jangka panjang. Salah satu jenis memori jangka pendek adalah memori bekerja. Fungsi ini
terjadi di otak manusia yang membutuhkan energi dalam jumlah besar dari degradasi glukosa makanan
sehari-hari. Studi terakhir menyatakan tidak ada efek puasa pada fungsi kognitif mahasiswa, namun
untuk remaja belum diketahui. Maka, tujuan penelitian ini untuk mengetahui apakah puasa
mempengaruhi kemampuan kerja memori remaja. SPDMS dipilih sebagai kerja memori, dimana
subjek diminta untuk melakukan percobaan dalam dua kondisi: Puasa dan tidak puasa. Data dianalisa
menggunakan ANOVA dalam program statistik R. Hasil analisa menunjukkan bahwa puasa
mempengaruhi memori kerja. Kemampuan kerja meningkat pada kondisi puasa dikarenakan puasa
memberikan tingkat stress optimal yang dapat meningkatkan kinerja. Jenis kelamin juga menunjukkan
perbedaan hasil disebabkan oleh kemampuan otak laki-laki yang lebih baik dalam kemampuan spasial,
yang sangat diperlukan dalam tes SPDMS. Proses belajar juga berpengaruh, namun sedikit. Hal ini
disebabkan oleh kemampuan otak manusia untuk belajar secara efisien mengenai informasi baru.
Kesimpulan yang didapat adalah puasa merupakan faktor utama yang mempengaruhi kerja memori,
sedangkan sesi dan jenis kelamin hanya memberi sedikit pengaruh.
EFFECT OF MONDAY-THURSDAY FASTING
ON COGNITIVE FUNCTION OF TEENAGER
Raja Aria Octivano
G3413041
Minithesis
To obtain Bachelor’s of Science
In
Department of Biology
DEPARTMENT OF BIOLOGY
FACULTY OF MATHEMATIC AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY
2008
Title : Effect of Monday-Thursday Fasting on Cognitive Function of Teenager
Name : Raja Aria Octivano
NRP : G34103041
Approved:
Advisor 1
Advisor 2
Dr. Bambang Suryobroto
NIP 131779503
Prof. Dr. Akichika Mikami
Endorsed by:
Dean Faculty of Mathematic and Natural Sciences
Bogor Agricultural University
Dr. drh. Hasim, DEA.
NIP 131578806
Graduation Date:
FOREWORD
Praise the God for all kindness and benevolence, this minithesis is finally done.
People usually think fasting is a kind of activity that limits your body. Especially for people
who think if you don’t eat, you will have no power for your activity. Is this kind of think true? What
about Muslim people who perform fasting regularly? That is the purpose of this research, to find
whether fasting is truly a bad activity for your body, or the opposite, brings a good effect for you.
Writer acknowledgments send to Dr. Bambang Suryobroto and Prof. Dr. Akichika Mikami, MD
as writer’s advisors. Also deepest gratitude to Dra. Taruni Sri Prawasti, Dr.Ir. Achmad Farajallah,
M.Si, Dr. Ir. Diah Perwitasari, M.Si, Dr. Ir. Rika Raffiudin, M.Si, Ir. Tri Heru, M.Si, Ir. Tri Atmowidi,
M.si and all staff in Zoology laboratory for the support and kindness. To all my friends in Biology 40
who gave motivation and friendship. To Mr. Solay for all of your kindness, and all of my subjects for
their participation and motivation. Writer’s acknowledgment especially send to Parent and my lovely
“Queen” for their love, support, kindness, motivation, and their pray.
Hopefully, this minithesis could be useful.
Bogor, April 2008
RAJA ARIA OCTIVANO
CURRICULUM VITAE
Writer was born in Jakarta on 11th October 1985 as the first child from parent, Djoko Hadi
Tjiptanto and Ramayulis.
On 2003, writer graduated from SMU Labschool Rawamangun, Jakarta and entered the
Department of Biology, Faculty of Mathematic and Natural Sciences, Bogor Agricultural University
via ‘Undangan Saringan Masuk IPB’ (USMI).
On 2005, writer did field study at Situ Gunung, Sukabumi with “Effect of Light to Sellaginella
Leaf Surface” as a title and related topic. Writer also did field work on 2006 at Taman Safari Indonesia
Cisarua, Bogor with “Ex-Situ Conservation of Sumatran Tiger (Panthera tigris sumatrae) at Taman
Safari Indonesia” as a title. On 2007 writers become assistant in practical class of Basic Biology,
Animal Developing, and Animal Physiology.
.
CONTENTS
Page
LIST OF FIGURES ………………….………………………………………………………. .
VIII
LIST OF TABLES …………………………………………………………………………….
VIII
LIST OF APPENDIX ………………………………………………………….……………..
VIII
INTRODUCTION …………………………………………………………………………….
MATERIAL AND METHODS ...…………………………………………………………….
Method …………………………… ……………………………………………….……..
Procedures ……………………………………………………………………………..….
Statistical Analytic …………………………………………………………..……….……
1
1
1
2
2
RESULT …………………………………………………………………………….………...
Blood Glucose Level Measured…………………………………………………………….
Highest Level Achieved ……………………………………………………………...…….
Performance Achieved .…………………………………………………………………….
Reaction Time Attained ………………………………………………………………….
2
2
2
3
3
DISCUSSION ..…………………………………………………..……………….…………….
4
CONCLUSION …........................................................................................................................
4
REFERENCES…………………………………………………………………….…...………..
4
Appendix ………………………………………..……………………………….…………….
5
LIST OF FIGURES
Page
1 Scheme structures and procedures of DMTS task………..………………………………………
1
2 Model of experiment...……………………………………………………………………………
2
3 Highest level achieved during fasting condition………………………………………………….
2
4 Performance achieved from the 1st to 2nd session…………………………………………………
3
5 Performance achieved during fasting condition……….…………………………………………..
3
6 Reaction time attained during fasting condition…………………………………………………… 3
LIST OF APPENDIX
Page
1 ANOVA tables of highest level achieved………………………….………………………………
6
2 ANOVA tables of highest level achieved………………………….………………………………
7
3 ANOVA tables of highest level achieved………………………….……………………………… 8
4 Subject data………………………………………………………………………………………...
9
1
INTRODUCTION
Background
Cognitive function consists of many aspects,
such as perception, learning, memory, reasoning,
and speech (human) (Redmond 2006). It distincts
from emotion and volition. Memory is a complex
cognitive function that allows the recording,
maintenance, and utilization of new information
(Thompson 2005). Construction of memory
consists of two separate stages: encoding and
retrieval. Encoding refers to initial process of
information that will potentially be stored as
memory episodes. Retrieval refers to process
that result from the encoded episodes (Buckner
1998). Based on the storage capacity, memory
can be distinguished into two types: short-term
and long-term systems. Short-term memory has a
limited capacity and memory trace can
spontaneously fade within seconds, while the
long-term one has massive capacity and
durability (Baddeley 1996).
One kind of short-term memory is the
working memory. Working memory is the ability
to hold an item of information transiently in
mind in the service of comprehension, thinking,
and planning. It serves as a workspace for
holding items and information in mind as they
are recalled, manipulated, and / or associated to
other ideas and incoming information (Goldman
1996).
Cognitive function is processed in brain.
Brain is only a small part of our body, but
consumes large amount of energy. It uses about
20% of total body energy in order to perform
cognitive and other tasks. This energy comes
from glucose degradation (Benton 1998). The
brain uses glucose almost exclusively for its
energy needs and requires continual supply of
this sugar for normal function (Frissel 1990). An
overnight and morning fast could lower the brain
function such as has been shown for the lowering
of memory process and attention level of school
children (Pollit 1998). On the opposite, there is
evidence that short-term food deprivation has
little or no effect on cognitive function (Green
1995). The deficits of cognitive function
associated with spontaneous dieting are not due
to any direct physiological or nutritional effect.
Instead, psychological effect of this condition
might be more important.
Monday-Thursday fasting (MTFast) is a
religious and cultural fasting that is performed by
Indonesian people, including teenagers. MTFast
provides a model of how caloric restriction
influences performance on memory task.
Erlangga (2006) showed that visual and spatial
working memory of university students didn’t
affected by this kind of fasting. All of the
subjects had study experience for 14 years or
more, so generally they are highly intelligence.
In average, they could reach high performance
on working memory task. Both sex (male and
female) had a same performance on memory
task. On the other hand, learning process was
found as a primary factor influencing the
memory task performance. Currently there is no
data for memory task performance of younger
people, such as teenager in junior high school. In
this research, I will show you the positive effect
of MTFast on working memory of teenager.
Objective
To find whether MTFast influences
performance on memory task of teenager.
MATERIAL AND METHODS
Place and Time
Research was done from March 2007 until
February 2008. Primary data collection was
taken at junior high schools in Jakarta. Data
analysis was done at Section of Biosysthematics
and Ecology of Animals, Department of Biology,
Faculty of Mathematics and Nature Sciences
Bogor Agricultural University.
Method
Working
memory
involves
spatial,
phonological and somatosensory memories
(Baddeley 1996). In this research, visual and
spatial memories are the primary basic for
Sequential Probe Delayed Matching to Sample
(SPDMS) task. This task means the subject must
choose the right stimulus, on the right order,
after a short delay (Elliot 1999). Stimuli were
presented as pictures of irregular shapes. The
scheme of SPDMS task can be seen in Figure 1.
1500ms
blank
1500ms
stimulus 1
1500ms
blank
1050ms
indicator
l
F) of fasting is 0.75 % and
interaction of fasting and glucose is 9.4 % which
is below 10% (see Appendix 1). This value
indicates that fasting and glucose had the highest
possibility of affecting the highest level
achieved.
If we abandon sex and session, and retaining
fasting and glucose value, we got fasting as the
main factor affecting highest level achieved.
However, comparison of both models show that
they explained the data similarly (Appendix 1),
so we may chose model 2 as the simpler one for
further discussion.
Performance Achieved
Figure 4 and 5 show an increasing mean of
performance according to sessions and
conditions.
Both factors were affecting performance
achieved.
The result of ANOVA between factors that
possibly affecting performance achieved shows
that the value of Pr(>F) of fasting is 0.13%
which is below 5% (see Appendix 2). This value
indicates that fasting had the highest possibility
to affect performance achieved.
If we abandon session, sex and glucose, and
retaining fasting value, indeed we got fasting and
session as the main factor affecting highest level
achieved. Comparison showed that both model
explained the data similarly (Appendix 2), so we
may chose model 2 as the simpler one for further
discussion.
Reaction Time
Figure 6 shows a decreasing mean of
reaction time during fasting condition for male.
Note there is a different slope for each sex. This
means that the way male and female reacts under
fasting or no fasting condition were different.
The result of ANOVA between factors that
possibly affecting reaction time shows that the
value of Pr(>F) of sex is 1.34% and fasting is
5.56%, and the value of sex and fasting
interaction is 7.8% which is below 10% (see
Appendix 3). This value indicates that sex and
fasting had the highest possibility of affecting
reaction time.
If we abandon session and glucose, and
retaining fasting and sex value, indeed we got
fasting as the main factor affecting reaction time.
There was also a difference between male and
female on reaction time attained. Comparison
showed both model may explained the data
similarly (Appendix 3), so we may chose model
2 as the simpler one for further discussion.
Figure 4. Performance achieved from the 1st to
2nd session.
Figure 5. Performance achieved during fasting
condition.
Figure 6. Reaction time attained during fasting
condition.
4
In summary, result shows that there were
significant effects of fasting on working memory
task. Highest level achieved, performance
achieved, and reaction time were affected by
fasting condition. Session gave a small effect in
performance, and sex also showed a small
difference between male and female reaction
time.
DISCUSSION
Glucose is the main metabolite of brain and
working muscle. Homeostasis system in human
body performs metabolic adaptation to maintain
blood glucose level as constant as possible.
During starvation, glucose will be synthesized
from the glycerol product of triacylglycerol
breakdown and the amino acids from the
proteolytic degradation of proteins. Muscle is the
major source for these materials. Measurements
of peripheral blood glucose level in no fasting
and fasting condition showed only small
degradation that was still in a normal range. We
may safely assume that glucose level in brain
also in normal range. However, fasting is a form
of stress in human.
Some study showed that human works better
under certain psychological stress conditions
(Bourne 2003). Besides, without any supply of
food, digestion system will suspend their activity
so they don’t require energy. This energy can be
shifted to other system such as the neural system.
Present research shows that, under the
circumstances that nutrition level was not
harmed, subjects achieved higher working
memory performance while in fasting condition.
Performances of working memory task were
increased. They were shown by higher level
achieved, influencing better performance
attained for all subjects, and shorter reaction time
for male.
Male had a significantly shorter reaction
time under fasting condition, while female did
not. This result came from the different way of
male and female’s brain work. Male’s brain has
better spatial ability than female (Pease 2001).
Spatial skill is necessary in SPDMS task because
the target objects appears in random position.
Session gave small influence in working
memory task. Performance got better on the 2nd
session, as a result of learning process carried
over from the 1st session, so they became
familiar and more efficient while doing the task.
Previous study (Erlangga 2006) also showed that
learning process was carried over affecting
working memory task. So, from these facts we
found that human brain is easy and efficient for
learning new information.
CONCLUSION
Fasting influences teenager’s visual and
spatial memory task although learning process
and sex difference modulate this effect.
REFERENCES
Baddeley A. 1996. The fractionation of working
memory. Proc Natl Acad Sci 9:1346813472.
Benton D, Parker PY. 1998. Breakfasts, blood
glucose, and cognition. Am J Clin Nutr
67:772-781.
Bourne LE, Yaroush RA. 2003. Stress and
cognition: a cognitive psychological
perspective. USA: NASA
Buckner RL, Koutstaal W. 1998. Functional
neuroimaging studies of encoding, priming,
and explicit memory retrieval. Proc Natl
Acd Sci. 95: 891-898.
Elliot R. 1999. Differential neural responses
during performance of matching and
nonmatching to sample tasks at two delay
intervals. J Neuroscience 19(12):5066–
5073.
Erlangga D. 2006. Effect of Monday-Thursday
fasting on cognitive function. Bogor: IPB
Frissel WR. 1990. Human Biochemistry. USA:
Macmillan Publishing Co Inc.
Goldman PS. 1996. Regional and cellular
fractionation of working memory. Proc Natl
Acad Sci. 93:13473-13480.
Green MW, Elliman NA, Rogers PJ. 1995. Lack
of effect of short-term fasting on cognitive
function. J Psychiat Res 29(3): 245 253,
Pease B, Pease A. 2001. Why men don’t listen
and women can’t read maps. Great Britain:
Orion Publishing Group.
Pollit E, Jacoby E. 1998. Fasting and cognition
in well and undernourished school children.
Am J Clin Nutr 67:779-812.
Redmond WA. 2006. Cognition. Microsoft
Encarta [DVD]. Microsoft Corporation,
2005.
Thompson F, Madigan SA. 2005. Memory: The
Key to Consciousness. Washington DC:
Joseph Henry Press.
5
APPENDIX
6
Appendix 1. ANOVA tables of highest level achieved.
Model 1. ANOVA result of how fasting, sex, session and glucose influence to highest level achieved.
Sex
Fasting
Session
Glucose
Sex : Fasting
Fasting : Session
Sex : Glucose
Fasting : Glucose
Session : Glucose
Sex : Fasting : Glucose
Df
1
1
1
4
1
1
4
4
1
2
Sum Sq.
0.150
12.150
0.171
2.161
0.141
1.363
3.162
13.077
0.218
0.923
Mean Sq.
0.150
12.150
0.171
0.540
0.141
1.363
0.791
3.269
0.218
0.462
Residuals
39
59.467
1.525
F value
0.0984
7.9683
0.1124
0.3543
0.0927
0.8941
0.5185
2.1441
0.1427
0.3027
Pr (>F)
75.55% NS
0.75% *
73.92% NS
83.95% NS
76.23% NS
35% NS
72.26% NS
9.4% *
70.77% NS
74% NS
Model 2. ANOVA result of fasting and glucose factors to highest level achieved.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Fasting
Glucose
Fasting : Glucose
1
4
4
12.150
2.245
11.022
12.150
0.561
2.755
8.911
0.4153
2.0391
0.42% *
79.68% NS
10.3% NS
Residuals
50
67.567
1.351
Comparison of each statistic models.
Model 1: Level ~ Sex * Fasting * Session * Glucose
Model 2: Level ~ Fasting * Glucose
Res. Df
39
50
RSS
59.467
67.567
Df
Sum of Sq
F
Pr(>F)
-11
-8.100
0.4829
90.3% NS
7
Appendix 2. ANOVA tables of performance attained.
Model 1. ANOVA result of how fasting, sex, session and glucose influence to performance achieved.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Sex
Fasting
Session
Glucose
Sex : Fasting
Fasting : Session
Sex : Glucose
Fasting : Glucose
Session : Glucose
Sex : Fasting : Glucose
1
1
1
4
1
1
4
4
1
2
134.4
2176.8
401.0
112.7
41.1
171.3
437.9
1186.5
157.5
46.2
134.4
2176.8
401.0
28.2
41.1
171.3
109.5
296.6
157.5
23.1
0.7426
12.0277
2.2158
0.1557
0.2268
0.9464
0.6049
1.6389
0.8704
0.1278
39.4% NS
0.13% *
14.5% NS
95.9% NS
63.6% NS
33.7% NS
66.1% NS
18.4% NS
35.7% NS
88% NS
Residuals
39
7058.4
181
Model 2. ANOVA result of fasting factors to performance achieved.
Fasting
Residuals
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
1
58
2176.8
9747.1
2176.8
168.1
12.953
0.06% *
Comparison of each statistic models
Model 1: Performance8 ~ Sex * Fasting * Session * Glucose
Model 2: Performance8 ~ Fasting
Res.Df
39
58
RSS
7058.4
9747.1
Df
Sum of Sq
F
Pr(>F)
-19
-2688.7
1.131
71.3% NS
8
Appendix 3. ANOVA tables of reaction time attained.
Model 1. ANOVA result of how fasting, sex, session and glucose influence to reaction time attained.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Sex
Fasting
Session
Glucose
Sex : Fasting
1
1
1
4
1
189282
109739
35503
81659
91786
189282
109739
35503
20415
91786
6.7153
3.8933
1.2596
0.7243
3.2564
1.34% *
5.56% *
26.86% NS
58.1% NS
7.8% *
Fasting : Session
1
1847
1847
0.0655
79.93% NS
Sex : Glucose
4
64740
16185
0.5742
68.3% NS
Fasting : Glucose
4
136351
34088
1.2094
32.24% NS
Session : Glucose
1
15457
15457
0.5484
46.34% NS
Sex : Fasting : Glucose 2
28697
14349
0.5091
60.5% NS
Residuals
1099278
28187
39
Table 6. ANOVA result of sex and fasting to reaction time attained.
Df
Sum Sq.
Mean Sq.
F value
Pr (>F)
Fasting
Sex
Fasting : Sex
1
1
1
109739
189282
149401
109739
189282
149401
4.3711
7.5394
5.9509
4.1% *
0.8% *
1.8% *
Residuals
56
1405917
25106
Analysis of Variance Table
Model 1: Reaction ~ Sex * Fasting * Session * Glucose
Model 2: Reaction ~ Fasting * Sex
Res.Df
39
56
RSS
1099278
1405917
Df
Sum of Sq
F
Pr(>F)
-17
-306640
0.6399
83.8% NS
9
Appendix 4. Subject data
Name
A
A
B
B
C
C
D
D
E
E
F
F
G
G
H
H
I
I
J
J
K
K
L
L
M
M
N
N
O
O
O
O
P
P
Q
Q
R
R
S
S
T
T
U
U
V
V
W
W
X
X
Y
Sex
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
M
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
F
Fasting
yes
no
yes
no
yes
no
yes
no
no
yes
yes
no
no
yes
yes
no
no
yes
no
yes
yes
no
yes
no
no
yes
yes
no
yes
no
yes
no
yes
no
yes
no
no
yes
yes
no
no
yes
no
yes
no
yes
no
yes
yes
no
no
Session
2
1
2
1
2
1
2
1
1
2
2
1
1
2
2
1
1
2
1
2
2
1
2
1
1
2
2
1
2
1
2
1
2
1
2
1
2
1
1
2
1
2
1
2
1
2
1
2
2
1
1
Glucose
B
E
A
B
B
B
E
C
C
B
D
D
B
C
B
B
C
B
D
A
A
D
D
D
B
B
A
E
C
C
B
B
B
D
A
C
C
B
B
D
C
B
B
D
C
C
B
A
D
E
C
Level
3
3
5
5
6
5
5
5
2
4
4
3
5
6
4
3
3
5
2
2
6
5
5
4
3
2
4
3
3
1
4
3
5
4
3
3
3
4
3
3
3
5
5
5
2
6
3
5
5
5
3
Performance
70.30
56.30
81.30
60.40
89.80
76.70
69.10
75.70
66.90
52.10
71.10
65.60
46.90
75.40
68.60
55.20
59.90
75.30
61.20
64.70
75.10
67.70
69.40
52.90
70.30
53.20
85.10
67.70
53.60
82.10
64.90
62.50
67.00
56.20
64.60
61.50
88.50
48.80
50.50
53.60
70.30
75.30
50.30
78.80
74.80
72.40
50.50
75.30
87.80
59.00
59.40
Performance8
34.10
27.30
59.10
43.90
75.50
55.80
50.30
55.10
23.50
31.80
43.40
31.80
34.10
63.40
41.90
26.80
29.00
54.80
21.50
22.90
63.10
49.20
50.50
32.30
34.10
18.70
52.00
32.80
26.00
17.40
39.60
30.30
48.70
34.30
31.30
21.80
42.90
29.80
24.50
26.00
34.10
54.80
30.60
57.30
26.30
60.90
24.50
54.80
63.90
42.90
28.80
Reaction
1261
1640
1226
1467
1405
1513
1314
1637
1204
1062
1297
1539
1318
1440
1466
1594
1566
1505
1629
1448
1572
1977
1569
1528
1696
1329
1384
1531
1501
1720
1454
1384
1431
1356
1127
1367
1168
1356
1448
1443
1447
1449
1280
1467
1275
1536
1323
1506
1223
1291
1538
10
Y
Z
Z
AA
AA
AB
AB
AC
AC
F
F
F
F
F
F
F
F
F
yes
no
yes
no
yes
no
yes
yes
no
2
1
2
1
2
1
2
2
1
D
B
A
B
A
C
B
C
A
4
2
2
3
5
2
3
5
5
62.80
66.20
63.30
52.60
59.00
59.70
53.60
76.00
68.40
38.40
23.20
22.20
25.50
42.90
21.00
26.00
55.30
49.70
1458
1566
1332
1615
1597
1291
1195
1012
1033
EFFECT OF MONDAY-THURSDAY FASTING
ON COGNITIVE FUNCTION OF TEENAGER
RAJA ARIA OCTIVANO
G34103041
DEPARTMENT OF BIOLOGY
FACULTY OF MATHEMATIC AND NATURAL SCIENCES
BOGOR AGRICULTURAL UNIVERSITY
2008
ABSTRACT
RAJA ARIA OCTIVANO. Effect of Monday-Thursday Fasting on Cognitive Function of Teenager.
Supervised by BAMBANG SURYOBROTO and AKICHIKA MIKAMI.
Cognitive function consists many aspects, one of them is memory. Memory is a complex
cognitive function that allows the recording, maintenance, and utilization of new information. Memory
can be distinguished into two types: short-term memory and long-term memory. One part of short-term
memory is the working memory. All the function takes place in human brain which requires large
amount of energy which came from glucose degradation of daily food. A recent study shows there is
no effect of fasting on cognitive function of university student, but there is no current data about
teenager. So, the objective of this research is to find whether fasting influences performance on
memory task of teenager. Sequential Probe Delayed Matching to Sample (SPDMS) task was selected
as a memory task, which subjects was ordered to perform a test in two conditions: fasting and no
fasting. Data was analyzed by ANOVA implemented in R statistical program. The result shows that
fasting affected working memory task. Task performances got better under fasting condition, possibly
because the effect of stress on subjects performances. There were also influences from sex difference
due to male’s brain advantage in spatial skill which is necessary for SPDMS task. Learning process
from previous session also gave influence, but the effect was small. It is due to the efficiency of human
brain to study about new information. In conclusion, fasting was the main factor influencing working
memory task, while session and sex difference gave only small.
ABSTRAK
RAJA ARIA OCTIVANO. Efek dari Puasa Senin-Kamis terhadap Fungsi Kognitif Remaja.
Dibimbing oleh BAMBANG SURYOBROTO dan AKICHIKA MIKAMI.
Fungsi kognitif terdiri dari banyak aspek, salah satunya adalah memori. Memori adalah fungsi
kognitif yang kompleks yang memungkin penyimpanan, pengolahan, dan pemanfaatan informasi.
Berdasarkan kapasitas penyimpanannya, memori dibagi menjadi dua jenis: memori jangka pendek dan
memori jangka panjang. Salah satu jenis memori jangka pendek adalah memori bekerja. Fungsi ini
terjadi di otak manusia yang membutuhkan energi dalam jumlah besar dari degradasi glukosa makanan
sehari-hari. Studi terakhir menyatakan tidak ada efek puasa pada fungsi kognitif mahasiswa, namun
untuk remaja belum diketahui. Maka, tujuan penelitian ini untuk mengetahui apakah puasa
mempengaruhi kemampuan kerja memori remaja. SPDMS dipilih sebagai kerja memori, dimana
subjek diminta untuk melakukan percobaan dalam dua kondisi: Puasa dan tidak puasa. Data dianalisa
menggunakan ANOVA dalam program statistik R. Hasil analisa menunjukkan bahwa puasa
mempengaruhi memori kerja. Kemampuan kerja meningkat pada kondisi puasa dikarenakan puasa
memberikan tingkat stress optimal yang dapat meningkatkan kinerja. Jenis kelamin juga menunjukkan
perbedaan hasil disebabkan oleh kemampuan otak laki-laki yang lebih baik dalam kemampuan spasial,
yang sangat diperlukan dalam tes SPDMS. Proses belajar juga berpengaruh, namun sedikit. Hal ini
disebabkan oleh kemampuan otak manusia untuk belajar secara efisien mengenai informasi baru.
Kesimpulan yang didapat adalah puasa merupakan faktor utama yang mempengaruhi kerja memori,
sedangkan sesi dan jenis kelamin hanya memberi sedikit pengaruh.
1
INTRODUCTION
Background
Cognitive function consists of many aspects,
such as perception, learning, memory, reasoning,
and speech (human) (Redmond 2006). It distincts
from emotion and volition. Memory is a complex
cognitive function that allows the recording,
maintenance, and utilization of new information
(Thompson 2005). Construction of memory
consists of two separate stages: encoding and
retrieval. Encoding refers to initial process of
information that will potentially be stored as
memory episodes. Retrieval refers to process
that result from the encoded episodes (Buckner
1998). Based on the storage capacity, memory
can be distinguished into two types: short-term
and long-term systems. Short-term memory has a
limited capacity and memory trace can
spontaneously fade within seconds, while the
long-term one has massive capacity and
durability (Baddeley 1996).
One kind of short-term memory is the
working memory. Working memory is the ability
to hold an item of information transiently in
mind in the service of comprehension, thinking,
and planning. It serves as a workspace for
holding items and information in mind as they
are recalled, manipulated, and / or associated to
other ideas and incoming information (Goldman
1996).
Cognitive function is processed in brain.
Brain is only a small part of our body, but
consumes large amount of energy. It uses about
20% of total body energy in order to perform
cognitive and other tasks. This energy comes
from glucose degradation (Benton 1998). The
brain uses glucose almost exclusively for its
energy needs and requires continual supply of
this sugar for normal function (Frissel 1990). An
overnight and morning fast could lower the brain
function such as has been shown for the lowering
of memory process and attention level of school
children (Pollit 1998). On the opposite, there is
evidence that short-term food deprivation has
little or no effect on cognitive function (Green
1995). The deficits of cognitive function
associated with spontaneous dieting are not due
to any direct physiological or nutritional effect.
Instead, psychological effect of this condition
might be more important.
Monday-Thursday fasting (MTFast) is a
religious and cultural fasting that is performed by
Indonesian people, including teenagers. MTFast
provides a model of how caloric restriction
influences performance on memory task.
Erlangga (2006) showed that visual and spatial
working memory of university students didn’t
affected by this kind of fasting. All of the
subjects had study experience for 14 years or
more, so generally they are highly intelligence.
In average, they could reach high performance
on working memory task. Both sex (male and
female) had a same performance on memory
task. On the other hand, learning process was
found as a primary factor influencing the
memory task performance. Currently there is no
data for memory task performance of younger
people, such as teenager in junior high school. In
this research, I will show you the positive effect
of MTFast on working memory of teenager.
Objective
To find whether MTFast influences
performance on memory task of teenager.
MATERIAL AND METHODS
Place and Time
Research was done from March 2007 until
February 2008. Primary data collection was
taken at junior high schools in Jakarta. Data
analysis was done at Section of Biosysthematics
and Ecology of Animals, Department of Biology,
Faculty of Mathematics and Nature Sciences
Bogor Agricultural University.
Method
Working
memory
involves
spatial,
phonological and somatosensory memories
(Baddeley 1996). In this research, visual and
spatial memories are the primary basic for
Sequential Probe Delayed Matching to Sample
(SPDMS) task. This task means the subject must
choose the right stimulus, on the right order,
after a short delay (Elliot 1999). Stimuli were
presented as pictures of irregular shapes. The
scheme of SPDMS task can be seen in Figure 1.
1500ms
blank
1500ms
stimulus 1
1500ms
blank
1050ms
indicator
l
F) of fasting is 0.13%
which is below 5% (see Appendix 2). This value
indicates that fasting had the highest possibility
to affect performance achieved.
If we abandon session, sex and glucose, and
retaining fasting value, indeed we got fasting and
session as the main factor affecting highest level
achieved. Comparison showed that both model
explained the data similarly (Appendix 2), so we
may chose model 2 as the simpler one for further
discussion.
Reaction Time
Figure 6 shows a decreasing mean of
reaction time during fasting condition for male.
Note there is a different slope for each sex. This
means that the way male and female reacts under
fasting or no fasting condition were different.
The result of ANOVA between factors that
possibly affecting reaction time shows that the
value of Pr(>F) of sex is 1.34% and fasting is
5.56%, and the value of sex and fasting
interaction is 7.8% which is below 10% (see
Appendix 3). This value indicates that sex and
fasting had the highest possibility of affecting
reaction time.
If we abandon session and glucose, and
retain