Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study
The effects of an extract from saffron (Crocus sativus L.) on visual short-term memory (STM) were examined in 20 volunteers. The extract was obtained from saffron petals using 100% ethylic alcohol, concentrated by vacuum evaporation, dried, and encapsulated (30 mg per capsula). Ten participants r...
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| Опубліковано в: : | Нейрофизиология |
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| Дата: | 2014 |
| Автори: | , , , |
| Формат: | Стаття |
| Мова: | Англійська |
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Інститут фізіології ім. О.О. Богомольця НАН України
2014
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| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Цитувати: | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study / M. Ghodrat, H. Sahraei, J. Razjouyan, G.H. Meftahi // Нейрофизиология. — 2014. — Т. 46, № 3. — С. 271-278. — Бібліогр.: 22 назв. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1859646584086593536 |
|---|---|
| author | Ghodrat, M. Sahraei, H. Razjouyan, J. Meftahi, G.H. |
| author_facet | Ghodrat, M. Sahraei, H. Razjouyan, J. Meftahi, G.H. |
| citation_txt | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study / M. Ghodrat, H. Sahraei, J. Razjouyan, G.H. Meftahi // Нейрофизиология. — 2014. — Т. 46, № 3. — С. 271-278. — Бібліогр.: 22 назв. — англ. |
| collection | DSpace DC |
| container_title | Нейрофизиология |
| description | The effects of an extract from saffron (Crocus sativus L.) on visual short-term memory
(STM) were examined in 20 volunteers. The extract was obtained from saffron petals using
100% ethylic alcohol, concentrated by vacuum evaporation, dried, and encapsulated (30 mg
per capsula). Ten participants received the extract each day for three weeks, while other
10 subjects received encapsulated placebo. Then, the contrast sensitivity of a subject was
estimated; sinusoidal grating patches with different contrast levels (0 – 100%) were used
(experiment 1). In experiment 2, the retention of STM was assessed in two-force choice
tests, using a delayed match to sample paradigm. In experiment 3, the n-back memory test
with different interstimulus intervals (up to 14 sec) was used. It was found that subjects after
medication with the saffron extract demonstrated better correct memorizing of the preceding
visual stimuli (from two to five). At the same time, extract medication somewhat improved
retention of visual STM, but only for several intermediate interstimulus intervals, and the
effect was not very remarkable. Our findings buphasize the expedience to research of the
effects of physiologically active dietary constituents in humans.
На групі з 20 добровольців досліджували впливи екстракту шафрану (Crocus sativus L.) на візуальну короткочасну
пам’ять (КЧП). Екстракт отримували з пелюсток шафрану,
використовуючи 100 %-вий етиловий спирт, концентрували за допомогою випаровування під вакуумом, висушували та капсулювали (30 мг у капсулі). 10 учасників приймали екстракт один раз на добу протягом трьох тижнів, тоді
як інші 10 тестованих отримували плацебо (також у капсулах). В експерименті 1 визначали контрастну чутливість
кожного випробуваного. Використовували зображення решіток із ліній, контраст яких змінювався за синусоїдальним
законом; контрастність пред’явлених зображень варіювали
від 0 до 100 %. В експерименті 2 оцінювали ємність КЧП
випробуваних у тестах дворівневого вибору, застосовуючи
парадигму відтермінованої оцінки збігу зі зразком. В експерименті 3 використовували n-зворотний тест збереження пам’ятного сліду при різних інтервалах між візуальними
стимулами (до 14 с). Після курсового приймання екстракту
шафрану тестовані демонстрували кращий рівень коректного запам’ятовування двох–п’яти попередніх візуальних стимулів. У той же час позитивний вплив екстракту на збереження зорових слідів у КЧП хоч і проявлявся, проте лише
для деяких проміжних міжстимульних інтервалів, і він був
менш значним. Наші спостереження підкреслюють доцільність дослідження ефектів фізіологічно активних компонентів, які входять до складу продуктів харчування.
|
| first_indexed | 2025-11-30T03:13:38Z |
| format | Article |
| fulltext |
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3 271
UDC 612.821.1+615.322
M. GHODRAT1, H. SAHRAEI1, J. RAZJOUYAN2, and G. H. MEFTAHI1
EFFECTS OF A SAFFRON ALCOHOLIC EXTRACT ON VISUAL SHORT-TERM
MEMORY IN HUMANS: A PSYCHOPHYSICAL STUDY
Received February 6, 2014.
The effects of an extract from saffron (Crocus sativus L.) on visual short-term memory
(STM) were examined in 20 volunteers. The extract was obtained from saffron petals using
100% ethylic alcohol, concentrated by vacuum evaporation, dried, and encapsulated (30 mg
per capsula). Ten participants received the extract each day for three weeks, while other
10 subjects received encapsulated placebo. Then, the contrast sensitivity of a subject was
estimated; sinusoidal grating patches with different contrast levels (0 – 100%) were used
(experiment 1). In experiment 2, the retention of STM was assessed in two-force choice
tests, using a delayed match to sample paradigm. In experiment 3, the n-back memory test
with different interstimulus intervals (up to 14 sec) was used. It was found that subjects after
medication with the saffron extract demonstrated better correct memorizing of the preceding
visual stimuli (from two to five). At the same time, extract medication somewhat improved
retention of visual STM, but only for several intermediate interstimulus intervals, and the
effect was not very remarkable. Our findings buphasize the expedience to research of the
effects of physiologically active dietary constituents in humans.
Keywords: saffron; short-term memory, visual memory, contrast sensitivity test, delayed
match to a sample paradigm, n-back memory test.
1Neuroscience Research Center, Baqiyatallah (a.s.), University of Medical
Sciences, Tehran, Iran.
2Electrical Engineering Faculty, Garmsar Branch of the Islamic Azad
University, Garmsar, Iran.
Correspondence should be addressed to G. H. Meftahi
(e-mail: meftahi208@yahoo.com or hosein.meftahi@gmail.com).
INTRODUCTION
Memory is one of the most crucial human capabilities;
its impairments can cause serious health problems.
Generally, human memory is divided into two types,
short-term memory (STM), allowing one to recall
for a period of several seconds up to 1 min without
rehearsal, and long-term memory (LTM) able to store
much larger amounts of information for a potentially
unlimited duration [1 – 3]. Information, after a short
time, is transmitted from STM to LTM [4, 5]. Therefore,
impairments of STM can cause different problems for
LTM. Thus, the search for ways or medications that
can improve STM has long been considered.
The effects of dieting or different dietary substances
on cognitive functions and memory configuration
were studied by many researchers [6, 7]. “Everyday”
or frequently consumed food may contain some
neurochemically active substances. Studies on
laboratory animals showed that certain foods and low-
calorie diets are beneficial for cognitive functions
[8 – 11]. These facts showed a direct relationship
between characteristics of food and brain functions.
The number of studies of the effects of nutrients on
brain functions in humans are, however, much fewer
than those using animal models despite examination of
the respective effects of agents present in ”everyday“-
consumed human diets is quite expedient.
In our study, we assessed the effect of a saffron
(Crocus sativus L .) extract on human STM
considering that little is known about the respective
effects. Saffron has been extensively used as a spice
in cooking and, since ancient times, in traditional
medicine as an herbal remedy with different effects
[12, 13]. Bitter taste of saffron is due to the presence
of a substance called picrocrocin. This substance,
during processing of a fresh plant due to thermal or
enzymatic decomposition, is converted in to aromatic
aldehyde named safranal. Crocin is responsible for the
color of saffron. Crocin itself consists of glycosides
that contain a carotenoid (called crocetin) and sugars.
[14].
As was mentioned, the configuration of LTM is built
after information has been transmitted from STM.
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3272
M. GHODRAT, H. SAHRAEI, J. RAZJOUYAN, and G. H. MEFTAHI
There exists a crucial issue whether some type of
herbal remedy (alcoholic saffron extract, ASE, in our
case) can boost STM or not? The positive outcome of
the hypothesis will prove the result of pioneer studies,
which indicated positive effects of food and diet on
improvements of STM indirectly. In our study, we
evaluated the effect of ASE on two aspects of visual
ATM, the retention and the capacity of this type of
memory.
METHODS
Examined Group. Twenty volunteer participants
participated in our psychophysical texts. These
subjects were enrolled and randomized, considering
their ages, in two identical groups, 10 subjects in each.
The first group received placebo, while the second
group received ASE (both encapsulated). Before such
medication, all subjects participated in visual STM
tests. Then, all subjects received their medications,
either placebo or ASE, for three weeks in a highly
regular double-blind manner. The test taker did not
know anything about the type of medications that
subjects received. After this period, all psychophysical
experiments were repeated in both groups. Each
experiment (estimation of the contrast sensitivity
and evaluation of the retention and capacity of STM)
lasted about 40 min, and the duration of a complete
experiment for one person was 2-2.5 h.
Preparation of ASE. Dried petal saffron was
obtained from the botany farm of the Medicine Faculty
of the Baqyiatallah (a.s.) University and sent to the
laboratory of the Pharmaceutical college of the Shahid
Beheshti Medicine University (Tehran, Iran). Saffron
was powdered, and 100 g of the powder was extracted
using 100% ethylic alcohol. The extract was separated,
filtered through Watman paper filters, concentrated by
vacuum evaporation, dried at low temperatures, and
encapsulated. Each capsule contained 30 mg ASE.
Psychophysical Experiments. To assess the
effect of ASE on human STM, we designed three
experiments. In the first experiment, we determined
the contrast sensitivity of a subject in response
to presentation of sinusoidal grating patches with
different contrast levels. The data obtained were taken
into account in the second experiment for assessing
the retention of STM. In the last experiment, we
evaluated the capacity of STM using different types
of stimuli. To perform the first test, a set of images
(sinusoidal grating patches) with various contrast
levels (from 0 to 100%) was generated. Figure 1A
shows several samples of the image data set. We ran
two-force choice tests. In each trial, a fixation cross
appeared at the center of the screen for 1.5 sec. This
long fixation time was used to remove the low-level
adaptation of previously presented images. Following
fixation the cross, a pair of randomly selected images
was presented simultaneously for 0.8 sec (separated
by a gap of 200 pixels). The participants were seated
approximately 90 cm from the monitor; the stimulus
display subtended 27×11 deg of visual angle. Subjects
were instructed to indicate if the images had the same
or different contrast level by pressing one of two
designated buttons on the computer keyboard (n and
m) and completed 420 trials each. Figure 1B shows
timing of this experiment. The latter was designed
using MATLAB software and Psych tool box [15, 16].
After obtaining the performance of all subjects
for different contrast levels at this step, a sigmoid
function that followed from Equation 1 was fitted
to the obtained data points to attain a subjects’
psychometric function. The intersection of this curve
with the 50% performance was selected as an index
F i g. 1. Examples of sinusoidal gratings with different contrast levels presented in the tests (A), and
scheme of the experiment procedure and timing for estimation of the contrast sensitivity of subjects
(B).
Р и с. 1. Приклади синусоїдальних решіток з різними рівнями контрасту, застосованих у тестах
(А), та схема експериментальної процедури для оцінки контрастної чутливості тестованих (В).
0 % 100 %
1.5 sec
0.8 sec
Select a key
A B
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3 273
EFFECTS OF A SAFFRON ALCOHOLIC EXTRACT
of the contrast sensitivity of each subject. This value
and psychometric function of two sample subjects are
represented in Fig. 2. The contrast sensitivity value
here means that if we increase the contrast difference
of the paired represented images above this value for
a particular subject, the subject can distinguish the
images more easily.
f (x) = 1
1 + e –( )x–a
b
(1)
To assess the retention of STM, we used a Delayed
Match to Sample (DMS) paradigm [17, 18]. After
presenting a fixation cross for 1.5 sec, a visual
stimulus (sinusoidal grating) appeared at the center of
the computer screen for 1 sec. After a delay period
(interstimulus interval, ISI), a pair of images appeared
on the screen for 1 sec. Participants were asked
to say which of the presented stimuli had appeared
previously. Generally, to make the experiment more
difficult for observers, two test stimuli should be very
similar to the original response-inducing stimulus. For
this purpose, two test images were displayed with a
contrast difference equal to the contrast sensitivity
value of each individual. Because of this, subjects
required attending to the test as much as possible.
As explained, after presenting the first stimulus, a
blank (grey) screen was presented within the ISI. The
duration of ISI was randomly sampled from 1.5 up
to 14 sec with 1.5 sec-long steps. The selection was
performed based on a uniform distribution; therefore,
we had an equal number of each time intervals (1.5,
3.0, 4.5, 6.0, 7.5, 9.0, 10.5, 12.0, and 14.0 sec).
Subjects completed two blocks consisting 135 trails.
They were instructed to remember the first stimulus
during the ISI and then select the correct stimulus after
presenting test images by pressing one of two keys
(n or m) on the computer keyboard. Needless to say
that one of the test stimuli is the previously presented
image, and the contrast difference of test images is
equal to the contrast sensitivity of the each participant.
It should also be noted that the location of test images
on the screen (right or left) in each trial was selected
randomly. Therefore, subjects could not guess where
the image would appear on the screen. This process
was repeated for each individual, and finally the
number of correct responses as a function of the time
difference was considered. Figure 3 illustrates the
experimental procedure.
After performing this test, the n-back memory test
for visual STM was used [19]. The n-back memory test
is one of the most popular experimental paradigms for
studying working memory, in which subjects are asked
to monitor the identity or location of a series of verbal
or nonverbal stimuli and to indicate when the currently
presented stimulus is the same as that presented n
trials earlier [20-21]. We used series of visual stimuli
designed and generated using MATLAB. Some image
samples from the collection are shown in Fig. 4A.
On each trial, a fixation cross appeared on the screen
0
0 30
%
252015105
0.2
0.4
0.6
0.8
1.0
1 sec
1.5 to 14 sec
1 sec
1.5 sec
Select a key
F i g. 2. Two sample psychometric functions for different contrast
levels demonstrated by two participants. Intersections of the curves
with the threshold line specifies the contrast sensitivity of each
individual.
Р и с. 2. Два графіки психометричних функцій для різних рівнів
контрасту, продемонстрованих двома тестованими.
F i g. 3. Experimental procedure for the measurement of short-term
memory retention and timing of image presentation. The interval
between the first image and the test image presentations is randomly
changed. Contrast differences between the two pictures shown side
by side is equal to the contrast sensitivity of each individual.
Р и с. 3. Експериментальна процедура для оцінки якості
зберігання в короткочасній пам’яті та часові характеристики
представлення зображень.
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3274
M. GHODRAT, H. SAHRAEI, J. RAZJOUYAN, and G. H. MEFTAHI
for 1 sec. Then a series of randomly selected images
were shown at the center of the screen. Each image in
the series was presented for 0.7 sec. Following serial
presentation, two individual images were displayed,
and the participant was asked to indicate which
stimulus was similar to a previously shown image.
The test stimuli were presented for 2 sec. Normally,
subjects can remember the last penultimate and the
two end stimuli. This generally indicates that the STM
capacity is limited. We used these types of stimuli to
eliminate the confounding effect of familiar visual
stimuli and generate a novel set of stimuli, which are
not very easy to memorize. It is worth mentioning that
the location of test images on the screen (right or left)
in each trial was selected randomly. Therefore, subjects
could not guess where the image would appear on the
screen. Subjects completed 60 trials for each order of
sequence (block). We continued the experiment until
n = 7 (seven end stimulus) was attained. The
experiment procedure is shown in Fig. 4B.
RESULTS
According to the accessible literature, no studies have
so far assessed the effect of saffron (ASE) on human
STM. The main question addressed in this study is
whether saffron constituents can improve human
STM. In this study, we considered two properties of
STM, the retention and capacity; two psychophysical
experiments were designed to evaluate their
characteristics.
Figure 5 demonstrates the results of the experiment
for visual STM capacity (n-back test). The averages
2 sec
1.0
A B
0.9
0.8
0.7
0.6
0.5
–7
1
1
2
2
–7–6 –6–5 –5–4 –4–3 –3–2 –2–1 –10 0
0.7sec
0.7sec
1 sec
Select a key
F i g. 4. Examples of the images
used in the test of short-term
memory capacity (A) and the
experimental procedure for
testing this capacity and timing
of image presentations (B).
Р и с. 4. Приклади зобра-
жень, використаних для тес-
тування місткості коротко-
часної пам’яті (А), та експе-
риментальна процедура для
оцінки такої місткості (В).
F i g. 5. Performance of participants in the experiment on short-term memory capacity. A) Performance before (1) and after (2) medication
for alcoholic saffron extract recipients. B) That before (1) and after (2) medication for placebo recipients. Abscissa) Order in sequence;
ordinate) normalized accuracy.
Р и с. 5. Показники учасників експериментів щодо оцінки місткості короткочасної пам’яті.
A B
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3 275
EFFECTS OF A SAFFRON ALCOHOLIC EXTRACT
and standard deviations for all participants in two
groups, placebo and ASE, are shown in this figure.
The horizontal axis shows the orders of sequence
of the presented images. In other words, number 0
represents the last presented image in the series of
consecutive images. Similarly, number 1 shows the
penultimate presented image, number 2 indicates
the two to end image, and so on. The vertical axis in
Fig. 5 also shows the performance of subjects in
detecting the correct stimulus (memorizing stimulus).
As it was predicted by increasing the difficulty of
the test, the performance of subjects dwindles. For
example, in remembering the 7th previously shown
image, the performance is at chance. Figure 5B
exhibits the performance of subjects who received
placebo before and after medication (curve 2 shows
the performance after medication, and curve 1 is for
before using placebo). It can be seen that there was
no significant difference in performance before and
after using placebo (B). On the other hand, subjects
who received ASE showed significant improvement in
performing the several order of sequences, as is shown
in Fig. 5A. This figure shows that the performances of
subjects in remembering images in four intermediate
stages are significantly different between pre-
consumption and post-consumption of ASE (sequences
of experiments in which a significant difference exists
are specified with asterisks). To test the significance of
these results, the t-test and the Kolmogorov – Smirnov
two-sample test [22] were used (t-test, P < 0.003, and
Kolmogorov – Smirnov test, P < 0.006). There was
no significant difference in the results of two first
stages of experiments due to the test simplicity. In
other words, healthy people are able to do such tasks
easily. Similarly, the lack of significant difference
in the final stages of testing resulted from the high
level of difficulty. In the last stages, the number of
presented images in the sequence is increased, and the
overall similarities between images are rather high; so,
it is very difficult for a person to memorize the images
in the process. Therefore, there is no significant
difference in the outcomes of the before and after of
medication. Based on the results, it can be stated that
the use of ASE improves STM capacity, and its impact
is significant.
Another experiment was conducted to evaluate the
effect of ASE on the retention of visual STM. The
results of this experiment are shown in Fig. 6. The
horizontal axis in this figure shows time intervals
between the first presented image (response image)
and the test images shown after; the vertical axis
also shows the performance of correct responses in
remembering images. As was expected, the errors
increased as the time interval between stimuli (response
and test) increased. Fig. 6B shows the results of the
placebo recipients before and after consumption. As
is shown, there was no significant difference between
before and after consumption. According to Fig. 6A,
it can be concluded that the performance of subjects
improved after taking ASE, but the improvement
was significant only for several intermediate times
marked with asterisks (t-test, P < 0.02; Kolmogorov –
1.0
A B
0.90
0.95
0.85
0.80
0.75
0.70
1.5 1.53.0 3.04.5 4.56.0 6.07.5 7.59.0 9.010.5 10.512.0 12.014.0 14.0
sec
F i g. 6. Performance of participants in the experiment on short-term memory retention. A) Performance before (1) and after (2) medication
for alcoholic saffron extract recipients. B) That before (1) and after (2) medication for placebo recipients. Abscissa) Time interval between
presentations, sec; ordinate) normalized accuracy.
Р и с. 6. Показники учасників експериментів щодо оцінки якості збереження у короткочасній пам’яті.
1
1
2
2
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3276
M. GHODRAT, H. SAHRAEI, J. RAZJOUYAN, and G. H. MEFTAHI
Smirnov test, P < 0.04). It should also be noted that
the significant differences in these time intervals were
not very remarkable. Figure 6A indicates that the use
of ASE exerted a smaller improving impact on the
retention of STM compared to the capacity of the latter.
These results shown in Fig. 6A are not too surprising
since, based on fundamental definitions, the retention
of STM is limited (approximately several seconds),
and anything more is needed to be transferred to LTM.
This fact also shows that improving the retention of
STM is limited but is achievable to some extent.
For further analysis, the overall performance of the
participants in both experiments and groups (recipients
of ASE or placebo) were calculated separately
to evaluate the overall effects of medication. As
stated earlier, each individual participated in both
experiments (the capacity and retention of STM). All
experiments were repeated after medication to evaluate
the effect of drugs on this type of memory. Therefore,
each individual has a performance before and after
medication. The average performance of each subject
in two tests was calculated in this step. This was done
to find an overall relationship between ASE effects
and memory. Figure 7A demonstrates the results of
subjects who received ASE (before and after using). In
this figure, each dot represents a person participating
in the experiment; the horizontal axis represents the
performance before, while the vertical axis represents
the performance after medication. Hence, any point
shows two numbers, one performance before and
another after medication. As is clear from Fig. 7A, the
overall performance of subjects who received ASE is
better than that in the group receiving placebo. The
performances of placebo recipients (Fig. 7B) are
around the mid-line and did not change significantly
before and after medication. However, most ASE
recipients are located in the area above mid-line (the
top-left) after medication (Fig. 7A).
Thus, the effects of ASE on visual STM was
assessed. Different studies have investigated the
effects of food type and various food diets on
memory. Most of these studies have been conducted
on laboratory animals; therefore, generalizing of these
results on human needs further research. In our study,
we used visual psychophysics to directly evaluate
such an effect in humans. This allows us to explore
the direct relationship between the remedy used and
human STM. To our knowledge, no studies have so
far assessed the effects of ASE on human STM. The
results of our study point out that ASE provides a
significant impact in on STM noticeably improving the
STM capacity. However, it exerts smaller, in general,
improving effects on memory retention.
One of the reasons that can cause problems
in memory and remembering the events is stress
and tension. Stress significantly affects some of
the cognitive processes in the brain. One of the
characteristics of the constituents of saffron is
smoothing of stress. So, it is possible that the
improvement of STM is one of the effects of indirect
factors in a complex of changes provided by a dietary
constituent (saffron) and directed toward reduction of
100 % A B
80
85
90
95
75
70
65
60
60 6065 6570 7075 7580 8085 8590 9095 95100 100
F i g. 7. Correlation fields for the joint performance in two tests of short-term memory capacity and retention for recipients of alcoholic saffron
extract (A) and for placebo recipients (B). Each dot represents a subject. Abscissa) Performance before, ordinate) that after medication, %.
Р и с. 7. Кореляційні поля об´єднаних результатів двох тестів щодо місткості короткочасної пам’яті та якості зберігання в ній для
учасників, котрі отримували алкогольний екстракт шафрану (А), та для тих, хто отримував плацебо (В).
%
NEUROPHYSIOLOGY / НЕЙРОФИЗИОЛОГИЯ.—2014.—T. 46, № 3 277
EFFECTS OF A SAFFRON ALCOHOLIC EXTRACT
the stress level. Our findings emphasize the expedience
of research of the effects of the respective constituents
in humans.
Acknowledgments. This work was supported by a grant
from Neuroscience Research Center, Baqiyatallah (a.s.)
University of Medical Sciences.
The experiments reported here were in accordance with
international standard ethical guidelines and approved by the
local Ethical committee (the Baqiyatallah (a.s.) University of
Medical Committee), Tehran, Iran. All participants gave their
written consent for their involvement in the tests.
The authors, M. Ghodrat, H. Sahraei, J. Razjouyan, and
G. H. Meftahi, have no conflict of interest.
М. Гходрат1, Х. Сахраєї1, Дж. Разджоуян2, Г. Х. Мефтахі1
ВПЛИВИ АЛКОГОЛЬНОГО ЕКСТРАКТУ ШАФРАНУ НА
ЗОРОВУ КОРОТКОЧАСНУ ПАМ’ЯТЬ ЛЮДИНИ: ПСИ-
ХОФІЗИЧНЕ ДОСЛІДЖЕННЯ
1 Дослідний центр нейронаук Бакійяталлах Медичного
університету, Тегеран (Іран).
2 Гамсарське відділення Ісламського університету Азад
(Іран).
Р е з ю м е
На групі з 20 добровольців досліджували впливи екстра-
кту шафрану (Crocus sativus L.) на візуальну короткочасну
пам’ять (КЧП). Екстракт отримували з пелюсток шафрану,
використовуючи 100 %-вий етиловий спирт, концентрува-
ли за допомогою випаровування під вакуумом, висушува-
ли та капсулювали (30 мг у капсулі). 10 учасників прийма-
ли екстракт один раз на добу протягом трьох тижнів, тоді
як інші 10 тестованих отримували плацебо (також у кап-
сулах). В експерименті 1 визначали контрастну чутливість
кожного випробуваного. Використовували зображення ре-
шіток із ліній, контраст яких змінювався за синусоїдальним
законом; контрастність пред’явлених зображень варіювали
від 0 до 100 %. В експерименті 2 оцінювали ємність КЧП
випробуваних у тестах дворівневого вибору, застосовуючи
парадигму відтермінованої оцінки збігу зі зразком. В екс-
перименті 3 використовували n-зворотний тест збережен-
ня пам’ятного сліду при різних інтервалах між візуальними
стимулами (до 14 с). Після курсового приймання екстракту
шафрану тестовані демонстрували кращий рівень коректно-
го запам’ятовування двох–п’яти попередніх візуальних сти-
мулів. У той же час позитивний вплив екстракту на збере-
ження зорових слідів у КЧП хоч і проявлявся, проте лише
для деяких проміжних міжстимульних інтервалів, і він був
менш значним. Наші спостереження підкреслюють доціль-
ність дослідження ефектів фізіологічно активних компонен-
тів, які входять до складу продуктів харчування.
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|
| id | nasplib_isofts_kiev_ua-123456789-148281 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 0028-2561 |
| language | English |
| last_indexed | 2025-11-30T03:13:38Z |
| publishDate | 2014 |
| publisher | Інститут фізіології ім. О.О. Богомольця НАН України |
| record_format | dspace |
| spelling | Ghodrat, M. Sahraei, H. Razjouyan, J. Meftahi, G.H. 2019-02-17T19:40:17Z 2019-02-17T19:40:17Z 2014 Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study / M. Ghodrat, H. Sahraei, J. Razjouyan, G.H. Meftahi // Нейрофизиология. — 2014. — Т. 46, № 3. — С. 271-278. — Бібліогр.: 22 назв. — англ. 0028-2561 https://nasplib.isofts.kiev.ua/handle/123456789/148281 612.821.1+615.322 The effects of an extract from saffron (Crocus sativus L.) on visual short-term memory (STM) were examined in 20 volunteers. The extract was obtained from saffron petals using 100% ethylic alcohol, concentrated by vacuum evaporation, dried, and encapsulated (30 mg per capsula). Ten participants received the extract each day for three weeks, while other 10 subjects received encapsulated placebo. Then, the contrast sensitivity of a subject was estimated; sinusoidal grating patches with different contrast levels (0 – 100%) were used (experiment 1). In experiment 2, the retention of STM was assessed in two-force choice tests, using a delayed match to sample paradigm. In experiment 3, the n-back memory test with different interstimulus intervals (up to 14 sec) was used. It was found that subjects after medication with the saffron extract demonstrated better correct memorizing of the preceding visual stimuli (from two to five). At the same time, extract medication somewhat improved retention of visual STM, but only for several intermediate interstimulus intervals, and the effect was not very remarkable. Our findings buphasize the expedience to research of the effects of physiologically active dietary constituents in humans. На групі з 20 добровольців досліджували впливи екстракту шафрану (Crocus sativus L.) на візуальну короткочасну пам’ять (КЧП). Екстракт отримували з пелюсток шафрану, використовуючи 100 %-вий етиловий спирт, концентрували за допомогою випаровування під вакуумом, висушували та капсулювали (30 мг у капсулі). 10 учасників приймали екстракт один раз на добу протягом трьох тижнів, тоді як інші 10 тестованих отримували плацебо (також у капсулах). В експерименті 1 визначали контрастну чутливість кожного випробуваного. Використовували зображення решіток із ліній, контраст яких змінювався за синусоїдальним законом; контрастність пред’явлених зображень варіювали від 0 до 100 %. В експерименті 2 оцінювали ємність КЧП випробуваних у тестах дворівневого вибору, застосовуючи парадигму відтермінованої оцінки збігу зі зразком. В експерименті 3 використовували n-зворотний тест збереження пам’ятного сліду при різних інтервалах між візуальними стимулами (до 14 с). Після курсового приймання екстракту шафрану тестовані демонстрували кращий рівень коректного запам’ятовування двох–п’яти попередніх візуальних стимулів. У той же час позитивний вплив екстракту на збереження зорових слідів у КЧП хоч і проявлявся, проте лише для деяких проміжних міжстимульних інтервалів, і він був менш значним. Наші спостереження підкреслюють доцільність дослідження ефектів фізіологічно активних компонентів, які входять до складу продуктів харчування. This work was supported by a grant from Neuroscience Research Center, Baqiyatallah (a.s.) University of Medical Sciences en Інститут фізіології ім. О.О. Богомольця НАН України Нейрофизиология Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study Впливи алкогольного екстракту шафрану на зорову короткочасну пам’ять людини: психофізичне дослідження Article published earlier |
| spellingShingle | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study Ghodrat, M. Sahraei, H. Razjouyan, J. Meftahi, G.H. |
| title | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study |
| title_alt | Впливи алкогольного екстракту шафрану на зорову короткочасну пам’ять людини: психофізичне дослідження |
| title_full | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study |
| title_fullStr | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study |
| title_full_unstemmed | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study |
| title_short | Effects of a Saffron Alcoholic Extract on Visual Short-Term Memory in Humans: a Psychophysical Study |
| title_sort | effects of a saffron alcoholic extract on visual short-term memory in humans: a psychophysical study |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/148281 |
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