ArticlePDF Available

Effects of the foliage plant on task performance and mood

Authors:

Abstract and Figures

In this study we investigate the effect of leafy plants on subjects' task performance and mood. As independent variables, two types of tasks and several room arrangements were used. There was an association or a sorting task and the room was arranged either with the plant placed in front of the subjects, to the side of the subjects, or with no plant placed in the room. Gender was also considered as a variable for analysis. Undergraduate students (F=63,M =83) performed either the association task or the sorting task under one of the three room arrangements. The association task was to create no more than 30 words for 20 different items. The sorting task was to sort 180 index cards into Japanese syllabary order.As for the task performance, Room×Gender interaction was significant in the scores of the association task (p<0·05). Male subjects working without plants performed worse than female subjects under the same conditions (p<0·01). Moreover, the task performances of the male subjects using the front arrangement were higher than that of the male subjects working without plants (p<0·10). It was concluded that the presence of the plants affected the association task more than the sorting task, and male subjects more than female subjects. It was also suggested that the presence of the leafy plants might affects creative work positively.
Content may be subject to copyright.
EFFECTS OF THE FOLIAGE PLANT ON TASK PERFORMANCE AND MOOD
SEIJI SHIBATA
1
AND NAOTO SUZUKI
2
1
Bunkyo Gakuin University, Saitama, Japan;
2
Doshisha University, Kyoto, Japan
Abstract
In this study we investigate the e¡ect of leafy plants on subjects’ task performance and mood. As independent
variables, two types of tasks and several room arrangements were used. There was an association or a sorting
task and the room was arranged either with the plant placed in front of the subjects, to the side of the sub-
jects, or with no plant placed in the room. Gender was also considered as a variable for analysis. Undergrad-
uate students (F¼63, M¼83) performed either the association task or the sorting task under one of the three
room arrangements. The association task was to create no more than 30 words for 20 di¡erent items. The
sorting task was to sort 180 index cards into Japanese syllabary order.
As for the task performance, Room Gender interaction was signi¢cant in the scores of the association
task (po0?05). Male subjects working without plants performed worse than female subjects under the same
conditions (po0?01). Moreover, the task performances of the male subjects using the front arrangement were
higher than that of the male subjects working without plants (po0?10). It was concluded that the presence of
the plants a¡ected the association task more than the sorting task, and male subjects more than female sub-
jects. It was also suggested that the presence of the leafy plants might a¡ects creative work positively.
#2002 Elsevier Science Ltd. All rights reserved.
Introduction
People often use foliage plants in rooms to change
the working environment. In recent years, arran-
ging plants in o⁄ces has become widespread in the
hope of enhancing the atmosphere of the indoor en-
vironment. There are various ways of plant arrange-
ment but usually plants are placed on a table or on
the £oor as a decorative feature, or sometimes ar-
ranged as a partitioning device. Asaumi et al.
(1995b) investigated residents’ feelings in rooms
where plants were arranged. Their results suggested
that people felt more ‘relaxed’and felt that the envir-
onment was more ‘intimate’ when plants were pre-
sent compared to situations where no plants were
provided or when lockers and screens were used in
lieu of plants. The plants used in their study were
such that they had an impact on the aesthetic qual-
ity of the room. Mintz (1972) said that the aesthetic
quality of a room in£uences people’s moods. He
found that the participants in his study were more
energetic and had a greater feeling of well-being in
an aesthetically pleasant room than in a room
which was aesthetically unpleasant. Thus, the re-
sults of the Asaumi et al.(1995a,b) study can be in-
terpreted to mean that the plants arranged in the
room improved the aesthetic quality of the room
and made subjects feel more ‘relaxed.
People also arrange plants in o⁄ces hoping to re-
duce the amount of stress such as eyestrain,
shoulder sti¡ness, back pain and mental fatigue, or
in order to recover from such types of stress (Kondo
& Toriyama, 1989; Asaumi et al., 1994, 1995a). It is
generally believed that looking at natural scenery
has an in£uence on people recovering from fatigue
or stress and it is also said that viewing such scen-
ery increases one’s feeling of well-being. Ulrich
(1984) reported that patients with views of natural
scenery outside their windows recovered faster than
those with views of brick buildings. Another study
showed that students who were shown nature ¢lms
recovered faster from stress, induced by seeing a
¢lm on workplace accidents, than those who were
shown ¢lms with urban settings (Ulrich et al.,
1991). Although most adults spend the greater part
of the day in workplaces, as Kaplan (1993) said,
Journal of Environmental Psychology (2002) 22, 265^272
0272- 4944/02/$-see front matter r2002 Elsevier Science Ltd. All rights reserved.
doi:10.1006/jevp.232, available online at http://www.idealibrary.com on
studies about the in£uence of nature were mainly
carried out in hospitals, prisons, or residential set-
tings, and little attention has been devoted to the
role of nature in the workplace.
However, several studies on the e¡ects of win-
dows on work also referred to the role of nature in
the working environment (Kaplan et al., 1972; Butler
& Steuerwald, 1991; Oiri et al., 1993; Leather et al.,
1998). These studies suggest that people prefer
rooms with windows to those without (Butler &
Steuerwald, 1991; Oiri et al., 1993), and that natural
scenery is preferred to urban scenery (Kaplan et al.,
1972). Windows also play the role of bringing natural
elements such as trees and plants indoors, so to
speak, and it has been reported that seeing natural
objects reduces work-related stress and in£uences
our overall well-being (Leather et al., 1998).
Although the e¡ects of windows are mainly posi-
tive on one’s mood, window views may have negative
in£uences on task performance (Stone & Irvine,
1993, 1994). Stone and Irvine (1994) found that the
in£uence of windows on ones performance depends
on the nature of the task. Simple repetitive tasks
such as ¢ling or computing can be performed better
in a windowless environment than in an environ-
ment which includes windows, while the latter en-
vironment is suited more to creative tasks than to
simple repetitive tasks. The researchers suggest the
possibility that the scenery viewed through the win-
dows might distract the attention of the subjects in
the ¢ling and computing tasks which require a high
degree of concentration. They suggest in addition
that the view through the windows might provide a
source of stimulation for creative tasks.
Larsen et al. (1998) investigated the relation be-
tween the density of plants and task performance
in the workplace using a letter identi¢cation task.
They found that the denser the plants, the worse
the task performance became, and that the denser
the plants the better the mood of the workers. Since
the task used in this study also required the sub-
jects’ concentration on the task, plants might have
distracted the subjects’ attention. They interpreted
these results by citing Isen’s (1993) idea that recall
of information becomes more active when subjects
are in a positive mood. That is, the recall of infor-
mation unrelated to the task increased when plants
were present, thus interfering with the subjects
task performance. If so, plants may a¡ect task per-
formance negatively regardless of the kind of task.
However, these would be cases in which plants in-
deed distract the attention of the subjects. In the
case of creative tasks, plants may exert a positive
in£uence as a source of inspiration or information.
In the current study, we used leafy plants as one
type of interior decoration object and investigated
how plants a¡ect subjects’ task performance and
mood. Two kinds of tasks were used, namely an as-
sociation task and sorting task. If the subjects im-
proved mood caused by the plants’ presence
stimulates the recall of much more information,
and the recall of information unrelated to the task
interferes with the subjects’ performance of the
task, as Larsen et al. (1998) found, the presence of
the plants may exert negative in£uences on both
kinds of tasks. If plants simply distract the atten-
tion of the subjects, without eliciting or stimulating
unrelated thought patterns, plants may negatively
a¡ect only the sorting task. Moreover, similar to
the results of the Stone and Irvine (1994) study, the
present study suggests that looking at plants may
positively a¡ect the carrying out of creative tasks
because plants provide a source of information. The
e¡ect of plants may also be dependent on how much
of the plants one can see. The e¡ect might be stron-
ger when the plants could be viewed directly and
more completely. In the current study, the amount
of plant visibility was controlled in two di¡erent
ways, one by placing the plants in front of the sub-
jects and the other by placing them to the side of
the subjects. The amount of plant visibility is much
greater when plants are placed in front of subjects
compared with when the plants are located to the
side of subjects.
Metho ds
Subjects
One hundred and forty-six undergraduate students
(M¼83, F¼63), who volunteered by signing up on
a participation roster took part. The students re-
ceived extra credit for their participation.
Tasks
An association task and a sorting task were used.
The association task required subjects to come up
with no more than 30 words associated with each
of 20 adjectives. For example, one part of the task
was to generate up to 30 words associated with
‘big’, and subjects were asked to write the words
down on a sheet of paper. The names of Japanese
universities were written on index cards and the
sorting task asked participants to sort these 180
index cards according to the Japanese syllabary.
266 S. Shibata and N. Suzuki
Similar to the procedure used by Stone and Irvine
(1994), the order of the cards was randomized, and
then the cards were numbered on their reverse sides
to ensure the same ordering for each subject.
Work environment
Figure 1 illustrates the arrangement of the leafy
plants and the room setting in this study. The room
used in this study is 235 cm (H)581cm
(D)278 cm (W), with one 89?5cm89?5 cm desk
and a chair. The room has one window on the south
side and one door on the north side of the room. The
room’s window was curtained and covered with
blinds so that the subjects could not see the outside
view. The desk was placed 180 cm from both the
south wall and the west wall. Subjects were seated
on the north side of the desk, facing south. We em-
ployed three conditions, one in which there were no
plants and the other two arrangements had plants
located in di¡erent positions (to the front or side).
A 1 m high, potte d p othos (Epiremnum aureum)was
chosen as a leafy plant because of its commonness
and general availability, and also because Asaumi et
al.(1995b) showed that familiar plants were pre-
ferred by most subjects. Under the ‘front’ condition,
the plant was placed in front of the subject, 145 cm
away from the desk, as shown in Figure 1, while un-
der the side’ condition it was placed on the right-
hand side of the subject, 145 cm away from the desk.
The ‘no plant’ condition indicates that no plants
were present in the room.
Questionnaire
To assess the subjects’ moods, we used a 7-point
Likert-type questionnaire. The scale consisted of 1
(strongly disagree) to 7 (strongly agree) points. We
used nine terms: ‘happy’, ‘tired, ‘calm’, ‘con¢dent’,
‘tense. ‘concentrated, ‘at ease’, ‘energized’, and dis-
tracted. In addition, eight more terms were used to
assess how the subjects felt about their task. The
terms used included energizing’, ‘fatiguing’, ‘easy’,
‘monotonous’, ‘boring’, ‘distracting’, ‘di⁄cult, and ‘con-
centration-requiring. The questionnaire also was
used to assess how the subjects felt about their
own performance. That is, how much the subjects
felt they had accomplished, and to what extent they
were con¢dent in doing their assigned task.
Furthermore, we asked the subjects to what extent
the room a¡ected them. Under the ‘front’ and ‘side
conditions, the subjects were asked to evaluate how
they felt about the plant. The terms used in the eva-
luation regarding the plant were, ‘calm, ‘lively’, dis-
tracted, ‘natural’, ‘familiar’, ‘tranquil, ‘unnatural’, and
concentrated. In addition, subjects were asked to
evaluate to what degree they paid attention to the
plant, and how much they felt the plant a¡ected
them when performing their task.
Procedure
Subjects were randomly assigned ‘front’, ‘side, or ‘no
plant’ conditions. Subjects were given an association
task or a sorting task. The number of subjects in the
association task was 73 in total (14 females and 10
males under the ‘front’ condition, 10 females and 15
males under the ‘side condition, and 10 females and
14 males under the ‘no plant’ condition). The number
of subjects carrying out the sorting task was 72 in
total (11 females and 13 males under the ‘front’ con-
dition, six females and 19 males under the side’ con-
dition, and 11 females and 12 males under the ‘no
plant’ condition).
After the subjects entered the room, they were
asked to sit and wait in the room for 5 min while
the experimenter was out of the room. Five minutes
later, the experimenter came back into the room
and the subjects were asked to evaluate their moods
according to the nine terms. Upon completion of the
evaluation, they were instructed how to perform
their task: in the association task, the subjects were
asked to ‘ygenerate up to 30 words associated with
each of the listed adjectives. There is no particular
order to follow in this association task. Thus, when
you get stuck with a particular adjective, you can go
on to the next one’ ; in the sorting task, the subjects
were asked to ‘ytake one card at a time from the
top of the pile and place it into a box in Japanese
syllabary order.
They were given 10 min for both the association
and the sorting task. After giving the subjects the
FIGURE 1. Room arrangement for each condition.
Foliage Plant and Task Performance 267
signal to start the task, the experimenter left the
room. When the time was up, the experimenter came
back into the room. For the task scores, the number
of words the subjects came up with was recorded for
the association task, and the number of sorted cards
in the box was recorded for the sorting task. The
cards were re-ordered after each sorting task ac-
cording to the numbers on their backs to ensure
the same ordering for each subject. Upon the com-
pletion of their tasks, the participants were asked
again to evaluate their moods, the tasks and the ef-
fect of the indoor environment. The subjects also
evaluated the e¡ects of the plant (except in the ‘no
plant’ condition).
Results
Task score
The task score for the association task was the total
number of words the subjects generated, while the
task score for the sorting task was the total number
of cards the subjects sorted. These two task scores
originated from the di¡erent kinds of tasks em-
ployed. Therefore, task scores were analysed sepa-
rately for each task using the Room Gender
analysis of variance (ANOVA). Figures 2 and 3 show
the mean task scores for each of the two tasks.
As for the association task, the Room Gender
interaction (F(2,67) ¼3?83, po0?05) and the main ef-
fect of Gender (F(1,67) ¼4?07, po0?05) were signi¢-
cant. The sub-analysis of the Room Gender
interaction showed the simple main e¡ect of Gender
to be signi¢cant under the ‘no plant’ condition
(F(1,67) ¼10?49, po0?01). Moreover, a weak simple
main e¡ect of Room on the male subjects
(F(2,67) ¼2?81, po0?10) was noted. With Tukey^Kra-
mer’s HSD test, the di¡erence between the task
score of the male subjects under the ‘front’ condi-
tion and under the ‘no plant’ condition showed a
weak signi¢cance (po0?10). These results showed
that male subjects achieved lower scores than fe-
male subjects under the ‘no plant’ condition.
As for the sorting task, there was no signi¢cant
Room e¡ect or Room Gender interaction on the
task score. However, there was a signi¢cant Gender
e¡ect (F(1,67) ¼6?07, po0?05). As can be seen in Fig-
ure 3, female subjects achieved higher scores than
male subjects.
Questionnaire
The di¡erences between the subjects’ pre and post-
task moods were analysed to evaluate the changes
in the subjects’ mood after doing their task. The
three-way crossed design (Room, Task and Gender)
multivariate analysis of variance (MANOVA) re-
vealed that the main e¡ect of the Task (F(9,126) ¼
2?63, po0?01) was signi¢cant in the mood evalua-
tions. Table 1 shows the mean di¡erences between
pre and post-task mood evaluations for both the as-
sociation task and the sorting task. The follow-up
analysis on Task e¡ect using test for additional in-
formation showed that the evaluation scores for
‘happy’ and calm’ in the sorting task decreased sig-
ni¢cantly as compared with the scores from the as-
sociation task (F(1,126) ¼4?92, po0?05; F(1,126)! ¼
8?25, po0?01, respectively).
The evaluation scores for how the subjects felt
about their task were also analysed using Room-
Task Gender MANOVA. The main e¡ect of
Task was signi¢cant (F(8,127) ¼2?68, po0?01). Table
2 shows the mean evaluations regarding the task
for the association and the sorting task. The
FIGURE 2. Task score for the sorting task under each room
condition.
FIGURE 3. Task score for the association task under each room
condition.
268 S. Shibata and N. Suzuki
follow-up analysis for Task e¡ect showed that
the sorting task was evaluated as being more ‘con-
centration-requiring’ than the association task
(F(1,127) ¼8?22, po0?01).
The evaluations the subjects made of their own
performance (how con¢dent the subjects felt in
doing their task, and to what extent they felt they
had accomplished the task) were highly correlated
(r¼0?65, po0?01). The three-way MANOVA (Room,
Task, and Gender) revealed that Task e¡ect was sig-
ni¢cant (F(8,127) ¼2?42, po0?05). The subjects eva-
luations of their own performance for each task
are shown in Table 3. The follow-up test for addi-
tional information showed that the subjects felt
more con¢dent doing the sorting task than the asso-
ciation task (F(1,133) ¼7?95, po0?01). However, the
e¡ect of the Task on the evaluation of the extent
which the subjects felt they had accomplished had
a weak signi¢cance (F(1,133) ¼3?86, po0?10).
The three-way analysis of variance (ANOVA) did
not show any signi¢cant main e¡ects or interactions
in the evaluation of the extent to which the room
environment a¡ected the subjects during task per-
formance. The mean of the evaluation was 3?71 (S.D.
¼1?63) on the 7-point scale ranging from 1 (not at
all a¡ected) to 7 (very much a¡ected).
The evaluations by the subjects under the ‘Front’
condition and the ‘Side’ condition were used in the
analysis regarding the leafy plant. The Room(2)-
Task (2) Gender(2) MANOVA showed that both
Task e¡ect and Gender e¡ect were signi¢cant in
the evaluations regarding the leafy plant
(F(10,80) ¼2?94, po0?01; F(10,80) ¼2?16, po0?05, re-
spectively). Table 4 shows the mean evaluations re-
lated to the plant for each of the task groups. The
follow-up test for additional information on Task ef-
fect showed that the kind of task had no signi¢cant
e¡ect on the evaluations of the plant’s in£uence on
the subjects. However, from the canonical variate
correlations (CVC) for each item as shown in Table
5, the evaluations for how much attention the sub-
jects paid to the plant (CVC ¼0?73) and to what ex-
tent the subjects felt a¡ected by the plant
(CVC ¼0?69) were found important for distinguish-
ing the di¡erences between Tasks. Furthermore, uni-
var i ate Fs of Task e¡ect were signi¢cant only for
the evaluation of how much the subjects paid atten-
tion (F(1, 89) ¼17?56, po0?01) and for the evaluation
of the extent the subjects felt they were a¡ected by
the plant (F(1,89) ¼15?39, po0?01). These results sug-
gest that the subjects in the sorting task group paid
less attention to the plant and felt less a¡ected by
the plant in doing their task.
Table 6 shows the means of the evaluations re-
garding the leafy plant for each gender. The test
TABLE 1
The mean di¡erences between the pre and the post-task mood
evaluations for both the association task and the sorting task
Task
Association Sorting
Va r i a b le s MS.D.MS.D.
Happy* 0?05 1?30 0?45 1?17
Tired 0?55 1?23 0?90 1?53
Calm** 0?62 1?32 1.40 1?39
Con¢dent 0?16 0 ?82 0?14 1?07
Ten se 0?21 1?07 0?32 1?51
Concentrated 0?79 1?44 1?15 1?50
At ease 0?42 1?33 1?05 1?55
Energized 0?05 1?10 0?02 1?25
Distracted 0?01 1?21 0?10 1?48
Note:n¼73 in each cell.
*po0?05.
**po0?01.
TABLE 2
The evaluations for how the subjects felt about their tasks
Task
Association Sorting
Va r i a b le s MS.D. MS.D.
Energizing 3?33 1?29 3?49 1?38
Fatiguing 4?71 1?32 4?90 1?20
Easy 3?73 1?42 4?12 1?13
Monotonous 4?78 1?57 5?21 1?18
Boring 4?51 1?37 4?40 1?44
Distracting 3?03 1?24 2?88 1?22
Di⁄cult 3?53 1?40 3?07 1?37
Concentration-requiring** 4?40 1?09 5?07 1?00
Note:n¼73 p er cel l.
po0?01.
TABLE 3
The evaluations the subjects made of their own performance
Task
Association Sorting
Va r i a b le s MS.D.MS.D.
To what extent the subjects
felt they had accomplished
the task
2?97 1?31 4?04 1?15
How con¢dent the subjects
felt in doing their task*
2?90 1?22 4?14 1?33
Note:n¼73 pe r cell.
po0?01.
Foliage Plant and Task Performance 269
for additional information of Gender e¡ect revealed
that female subjects felt the plant to be less distract-
ing (F(1,80) ¼6?02, po0?05) and had a greater feel-
ing of familiarity (F(1,80) ¼9?91, po0?01) towa rd
the plant.
Discussion
In this study, we investigated how the presence of a
leafy plant in a room a¡ected subjects’ task perfor-
mance and mood in two kinds of tasks, a sorting
task and an association task. The lower rating in
the mood evaluation scores for ‘happy’ and calm’
for the sorting task and the high rating in the task
evaluation score for ‘concentration-requiring’ for the
sorting task suggest that the sorting task was more
demanding than the association task.
However, the subjects showed that they felt more
con¢dent about their performance in the sorting
task. The sorting task was a simple repetitive task,
and the subjects could easily know how their task
performance was evaluated by the amount of cards
they had sorted. In contrast, the association task
was more complex than the sorting task and the
evaluation of the task performance would be based
not only on the amount of answers the subjects
produced but also on the quality of the answers.
TABLE 4
Mean evaluations related to the plant for each of the task groups
Task
Association* (n¼48) Sorting (n¼49)
Va r i a b le s MS.D.MS.D.
Calm 4?92 1?29 4?63 1?42
Lively 4?08 1?65 4?27 1?34
Distracted 2?44 1?44 2?29 1?15
Natural 4?08 1?80 4?35 1?52
Familiar 4?21 1?60 4?24 1?45
Tranquil 5?10 1?45 5?16 1?12
Unnatural 4?27 1?78 3?94 1?57
Concentrated 3?79 1?25 3?94 1?11
How much attention the subjects paid
to the plant
3?15 1?94 1?78 1?42
To what extent the subjects felt a¡ected
by the plant
3?15 1?81 1?80 1?22
*The data with missing values were excluded.
TABLE 5
Canonical variate correlations (CVC) for the evaluations
about the foliage plant
Va r i a b le s C VC
Calm 0?14
Lively 0?12
Distracted 0?12
Natural 0?11
Familiar 0?01
Tranquil 0?06
Unnatural 0?20
Concentrated 0?06
How much attention the subjects
paid to the plant
0?73
To what extent the subjects felt
a¡ected by the plant
0?69
TABLE 6
The Means of the evaluations regarding the plant for each
gender
Gender
Female (n¼41) Male* (n¼56)
Va r i a b le s MS.D.MS.D.
Calm 5?02 1?27 0?59 1?40
Lively 4?27 1?48 4?11 1 ?51
Distracted* 1?95 1?95 2?66 1?42
Natural 4?15 1?53 4?27 1?76
Familiar** 4?73 1?36 3?86 1?53
Tranquil 5?17 1?20 5?11 1?36
Unnatural 3?95 1?66 4?21 1?70
Concentrated 3?78 1?13 3?93 1?22
How much attention
the subjects paid
to the plant
2?54 1?75 2 ?39 1?88
To what extent the
subjects felt a¡ected
by the plant
2?63 1?65 2?34 1?70
w
The data with missing values were excluded.
*po0?05
**po0?01.
270 S. Shibata and N. Suzuki
Therefore, the subjects could not easily know which
aspects of the task performance were evaluated, and
as a consequence they felt less con¢dent about their
performance than in the sorting task.
Moreover, the subjects reported that they paid
less attention to the plant and felt less a¡ected by
the presence of the plant in the sorting task than
in the association task. This also means that the
subjects engaged in the sorting task did not have
as much time to look around the room as compared
with those in the association task. This was due to
the fact that the sorting task was in a sense more
demanding than the association task. Furthermore,
the sorting task revealed only the Gender e¡ect,
while the association task showed signi¢cant Gen-
der e¡ect and the Gender Task interaction. This
indicates that the subjects doing the sorting task
did not have much time to pay attention to the work
environment and the plant, thus reducing the possi-
ble e¡ects of the foliage plant on their performance.
The e¡ects of the leafy plant on performance
were clear for the male subjects in the association
task group. The male subjects recorded a higher
task performance under the ‘front’ condition than
under the ‘no plant’ condition. This suggests that
the presence of the plant could have a¡ected the
high performance on the association task with male
subjects. The fact that the visibility of the plant was
greatest under the ‘front condition, and that the dif-
ference in task scores was signi¢cant only when
comparing the ‘front’ and ‘no plant’ conditions, sug-
gests that the e¡ects of the plant were relative to
the degree of plant visibility. Contrary to our re-
sults, however, Larsen et al. (1998) found that the
denser the plants, the worse the task performance
became, whereas the mood evaluation was more po-
sitive as the density of plants increased. They inter-
preted these results as meaning that the subjects’
improved mood caused by the plants presence sti-
mulated the recall of much more information irrele-
vant to the task. Consequently, this information
interfered with the subjects’ performance of their
tasks. In contrast, our results suggest the possibi-
lity that the plant may have had positive e¡ects on
the task performances. Our ¢ndings were similar to
those of Stone and Irvine (1994), who investigated
the e¡ects of the presence of windows on task per-
formance. In their study, a room with windows had
the e¡ect of stimulating positive perceptions during
a creative task, similar to the situation in our asso-
ciation task. Stone and Irvine suggested that a view
from a window provided a source of information for
a creative task. Similar to their study, our results
suggest that having a plant within view was an ef-
fective facilitatory situation for the male subjects
doing the association task.
Although the subjects in the sorting task were
distracted by stimuli received from the window view
in the Stone and Irvine study (1994), the results of
our study showed the leafy plant had no e¡ect on
the sorting task. Clearly, a view from a window pro-
vides much more information than a view of only
one potted plant. As a result, it is possible that the
degree of stimulation caused by looking at the plant
was not great enough to distract the subjects doing
the sorting task. Therefore, there is still the possibi-
lity that the presence of a plant may distract sub-
jects involved in a simple repetitive task and a¡ect
positively the performance of a creative task.
It should be noted that these e¡ects were seen
only in male subjects. Female subjects showed high-
er task performance in both the sorting and the as-
sociation task, and evaluated the leafy plant as
being more ‘familiar’ and less ‘distracting’ than male
subjects. However, no gender-related di¡erence that
explains why these results were observed only in
male subjects was found. It was also suggested that
the subjects in the sorting task did not have much
time to pay attention to the work environment, mak-
ing the in£uence of the work environment on their
task negligible. Adopting a similar point of view,
there is the possibility that the female subjects
could have been more attentive to the task, thus
leading to their higher performance compared
with the male subjects. Assuming this to be the
case, their concentration could have lessened the
in£uence of the work environment on the execution
of the task. This possibility is strengthened due
to the fact that the female subjects evaluated the
plant as being less ‘distracting’ than the males.
However, this alternative explanation remains a
conjecture.
In the present study, we investigated the e¡ects of
a leafy plant on subjects’ task performance and
mood. The results suggest that the presence of the
plant worked as a facilitatory source of information
for creative work like the association task while its
presence did not a¡ect the subjects’ mood. In this
study, we evaluated the subjects as they performed
tasks over a short period of time and their mood
changes during that time period. It may be possible
that ones mood may be a¡ected by a plant (or
plants) and that this could be ascertained if data
were obtained over a longer period of time than in
the current study. The e¡ects suggested in this
study may not be plant speci¢c, for similar e¡ects
were suggested with other environmental elements
such as the presence of windows. More work is
Foliage Plant and Task Performance 271
needed to isolate the unique e¡ects of plants on hu-
man performance in the working environment.
Acknowledgements
We would like to acknowledge the useful comments
from Professor Shizuhiko Nishisato, University of
Toronto.
Note
Reprint requests and correspondence should be addressed
to Seiji Shibata, Department of Human Studies, Bunkyo
Gakuin University, 1196 Kamekubo, Oimachi, Iruma-gun,
Saitama-ken 356- 8533, Japan; E-mail: sshibata@hum.u-
bunkyo.ac. jp.
References
Asaumi, H., Nishina, H., Nakamura, H., Masui, Y. & Ha-
shimoto, Y. (1995a). E¡ect of ornamental foliage plants
on visual fatigue caused by visual display terminal
operation. JournalofShita,7, 138^143.
Asaumi, H., Nshina, H., Namba, R., Masui, Y. & Hashimo-
to, Y. (1995b). Evaluation of impression of ornamental
foliage plants and psychological rating of rooms with
ornamental foliage plants by means of semantic dif-
ferential method. JournalofShita,7, 34^45.
Asaumi, H., Nishina, H., Tsukanishi, K., Yoshinori, M. &
Hashimoto, Y. (1994). E¡ects of foliage plants on ther-
mal environment and comfort inside room: experi-
mental analysis in winter. Jour nal of Archit ecture,
Planning and Environmental Engineering: Transactions
of AIJ,464, 39^46.
Butler, D. & Steuerwald, B. (1991). E¡ects of view and
room size on window size preferences made in mod-
els. Environment and Behavior,23, 334^358.
Isen, A. (1993). Positive a¡ect and decision making. In M.
Lewis & J. M. Haviland (Eds), Handbook of Emotions.
New York: Guilford, pp. 261^277.
Kaplan, R. (1993). The role of nature in the context of
the workplace. Landscape and Urban Planning,26,
193^201.
Kaplan, S., Kaplan, R. & Wendt, J. S. (1972). Rated
preference and complexity for natural and urban
visual material. Perception and Psychophysics,12,
354^356.
Kondo, M. & Toriyama, T. (1989). Experimental research
on the e¡ectiveness of using green in reducing of vi-
sual fatigue caused by VDT operation. Journal of
the Japanese Institute of Landscape Architecture,52,
139^144.
Larsen, L., Adams, J., Deal, B., Kweon, B.-S. & Tyler, E.
(1998). Plants in the workplace: the e¡ects of plant
density on productivity, attitudes, and perceptions.
Environment and Behavior,30, 261^281.
Leather, P., Pygras, M., Beale, D. & Lawrence, C. (1998).
Windows in the workplace: sunlight, view, and occu-
pational stress. Environment and Behavior,30,
739^762.
Mintz, N. (1972). Bitekisinrigaku no ningenkankyou eno
ouyou [An application of aesthetic psychology to hu-
man environment]. In D. Canter & M. Inui (Eds),
Kankyo Shinri Towa Nani Ka. Tokyo: Shokokusha, pp.
13^50.
Oiri, M., Ohkura, M. & Kosugo, R. (1993). Improving ame-
nity in con¢ned underground workplaces (1): psycho-
logical e¡ects of embellished surroundings and
arti¢cial windows. Journal of Science of Labour,69,
133^144.
Stone, N. J. & Irvine, J. M. (1993). Performance, mood, sa-
tisfaction, and task type in various work environ-
ments: a preliminary study. TheJournalofGeneral
Psychology,120, 489^497.
Stone, N. J. & Irvine, J. M. (1994). Direct or indirect win-
dow access, task type, and performance. Journal of
Environmental Psychology,14, 57^63.
Ulrich, R. S. (1984). View through a window may in£uence
recovery from surgery. Science,224, 420^421.
Ulrich, R. S., Simons, R. F., Losito, B. D., Fiorito, E.,
Miles, M. A. & Zelson, M. (1991). Stress recovery
during exposure to natural and urban environ-
ments. Journal of Environmental Psychology,11,
201^230.
272 S. Shibata and N. Suzuki
... Bakker and Voordt [51] further noted that little attention had been paid to the type of plant or its state of health. The majority of the studies have been conducted in laboratory or quasi-office design [59][60][61][62][63]. A more limited number of studies targeting office workers in real office settings have also been conducted [53,[64][65][66][67][68][69][70]. ...
Article
Full-text available
In recent years, work-related stress has grown exponentially and the negative impact that this condition has on people’s health is considerable. The effects of work-related stress can be distinguished in those that affect workers (e.g., depression and anxiety) and those that affect the company (e.g., absenteeism and productivity). It is possible to distinguish two types of prevention interventions. Individual interventions aim at promoting coping and individual resilience strategies with the aim of modifying cognitive assessments of the potential stressor, thus reducing its negative impact on health. Mindfulness techniques have been found to be effective stress management tools that are also useful in dealing with stressful events in the workplace. Organizational interventions modify the risk factors connected to the context and content of the work. It was found that a restorative workplace (i.e., with natural elements) reduces stress and fatigue, improving work performance. Furthermore, practicing mindfulness in nature helps to improve the feeling of wellbeing and to relieve stress. In this paper, we review the role of mindfulness-based practices and of contact with nature in coping with stressful situations at work, and we propose a model of coping with work-related stress by using mindfulness in nature-based practices.
... 대중들로부 터 미세먼지와 대기 환경오염에 관한 관심이 날로 커지고 있기 때문에 미세먼지 저감효과가 주목되는 실내 관엽식물 (Kwon and Park, 2018;Abdo et al., 2016)의 소비는 앞으로도 지속적으로 증가할 전망이다. 실내 관엽식물은 미세먼 지 저감 기능 외에도 크기에 따라 스크린이나 파티션과 같이 기능적인 특징들을 제공하며 (Randani, 2017), 능률에서 나 심리적인 부분을 안정화 시키는 것에도 도움을 주기 때문에 (Shibata and Suzuki, 2002;Deng and Deng, 2018 (Abdo et al., 2016), 실내정원 (Jang et al., 2016) 등에서도 다양하게 활용되고 있으며 심미적, 공간적인 효과 및 안정감을 주기 위해 서비스를 이용하는 손 님들을 위한 휴식장소 주변에 주로 배치되어 활용되어지고 있다 (Deng and Deng, 2018). ...
Article
Full-text available
When designing interior spaces, the use of indoor foliage plants is considered as an integral part of providing a wonderful ambiance owing to both their aesthetic and functional properties. Being indoors, these plants are subjected to continuous lighting conditions at high temperatures with varying light intensities, which affect their survival, growth, and leaf color quality. Hence, this study was conducted to investigate the influence of different light intensity levels (60, 120, and 180 μmol m-2 s-1) on the growth and leaf color of commonly used indoor foliage plants (Hoya carnosa f. variegata, Epipremnum aureum f. variegata, Rhapis excelsa, Hedera helix, Chamaedorea elegans, and Spathiphyllum wallisii) under high temperature and continuous lighting conditions. The results demonstrated that the growth parameters of the indoor foliage plants, after 4 weeks of treatment, were relatively better when grown under lower light intensity levels (60 and 120 μmol m-2 s-1) compared to when grown under a higher light intensity level (180 μmol m-2 s-1). The CIELAB L * and b * values of a majority of the indoor foliage plants increased proportionally with the light intensity level, indicating that under a higher light intensity, the leaves tend to express yellow tones. In addition, SPAD units decreased as the light intensity increased. Taken together, the results of this study indicate that indoor foliage plants are sensitive to light stress under high temperature and continuous lighting conditions; therefore, it is recommended to cultivate them under relatively low light conditions (60 and 120 μmol m-2 s-1).
Chapter
Contextual influences in the workplace have been increasingly acknowledged as being crucial for enhancing creativity. Among various factors in the context surrounding employees, organizational culture and organizational climate have gained much attention in creativity research over the last decades. However, still many challenges exist about the role of culture and climate on creativity. For example, the literature stresses the importance of the physical work environment but research addressing physical aspects of the organizational context has received little attention. This chapter attempts to provide an overview of existing knowledge by synthesizing previous literature on organizational culture and climate influencing creativity. We focus on key issues and major trends. We further discuss perspectives for future research and important questions that remain to be answered. Finally, the chapter suggests some practical recommendations for organizational promotion of creativity.
Article
With the urban development, indoor air quality (IAQ) is of growing public health concern due to that fact people spend 80%–90% of their time indoors, which has prompted the use of plants to reduce the air pollution through the phytoremediation from interior spaces, especially in the enclosed rooms with air-conditioning and heating. Indoor plants have been proved to improve the indoor environment, relieve anxiety, and reduce CO2 concentration. However, the comprehensive review has not been published to summarize the development status and potential deficiencies of indoor green plants after 2018. The 50 published articles related to indoor green plants were selected by the primary retrieval system and the later manual screening. This review mainly focused on the effects of green plants on the indoor thermal environment and indoor pollutants including volatile organic compounds (VOCs), and CO2 concentration, while the application efficiency of green plants was described on learning or productivity efficiency, patients' post-operative recovery and emotion comprehensively.
Research
Full-text available
Modern lifestyles do influence Malaysian occupants to work long hours in a day in order to cope with large workloads and to meet a deadline. Majority of the occupants are overstressed, faced with negative emotions that lead to an unhealthy lifestyle. Studies show that nature is able to enhance human well-being by reconnecting human with natural elements in a built environment, which is known as biophilic design. Therefore, this study aims to create a biophilic design guideline to enhance occupants' well-being in heritage adaptive reuse indoor co-working space. This study is conducted in the Heritage World Site (WHS) in George Town, Penang. Mixed method research design was used to collect data from the site. Both qualitative and quantitative data were analysed using the triangulation method to validate the overall data and research by cross verifying the information from multiple methods to gather the data. The results proved that the existing biophilic design patterns do enhance co-workers' emotional well-being significantly and it can be used as design guideline. In addition, this study also investigated different ways of biophilic design patterns application which can affect the quality of biophilic experiences.
Article
Full-text available
Experience of nature is widely linked to wellbeing, including psychological restoration. Benefits to creativity have been explored in a limited number of studies which refer to theories of restorative environments as frameworks, but it is unclear which aspects of the environment and person-nature transactions are implicated in these processes. In this study, N = 20 members of the British public were interviewed regarding the relevance of natural environments for their personal and professional creative activities. Thematic analysis of interview transcripts revealed that cognitive, affective, and aesthetic appraisals were reported as directly relevant to creativity in nature, while environmental properties, sensory experiences, and the self were reported as informing these appraisals. Similarities to theories of restorative environments were observed in terms of the relevance of affect, cognition, and aesthetics. However, divergences also occurred, especially with regard to perceptions of arousal as beneficial for creativity, the importance of change in the environment, and the relevance of the self. Studies and theoretical modelling of relationships between nature and creativity should include these concepts, as well as those from theories of restorative environments.
Article
Full-text available
Hospitality industry plays a main role and has become a major sector in Malaysia’s economy. However, there are some challenges in the hospitality industry such as employee turnover which could have various consequences to organizations. The purpose of this research is to investigate the factors affecting employee turnover intention, either directly or indirectly. Previous studies have suggested that employee turnover intention could be affected by factors such as leadership, motivation, communication, work environment and infrastructure both directly and indirectly. Employee innovation and creativity as a mediating factor could also affect its relationship with turnover intention of employees. The research design for this study was quantitative research method using questionnaires as the data collection method. Purposive sampling was used to sample 152 hotel employees within the West of Malaysia. Structural Equation Modelling was used to analyze the data using SmartPLS software. Results indicated that leadership, motivation, communication, and work environment and infrastructure had significant relationship with employee innovation and creativity. Apart from that, leadership, motivation and communication also have significant relationship with the employee turnover intention. Turnover is a major issue within companies not only for the company’s sustainability, but also for the health and wellbeing of their employees. As an implication, organizations should understand that their leadership characteristic and environment has a tremendous impact to burnout and employee performance.
Article
Full-text available
This experiment measures the effects of indoor plants on participants' productivity, attitude toward the workplace, and overall mood in the office environment. In an office randomly altered to include no plants, a moderate number of plants, and a high number of plants, paid participants (N = 81) performed timed productivity tasks and completed a survey questionnaire. Surprisingly, the results of the productivity task showed an inverse linear relationship to the number of plants in the office, but self-reported perceptions of performance increased relative to the number of plants in the office. Consistent with expectations, participants reported higher levels of mood, perceived office attractiveness, and (in some cases) perceived comfort when plants were present than when they were not present. Decreased productivity scores are linked to the influence of positive and negative affect on decision making and cognitive processing.
Article
Full-text available
In order (1) to study the relationship between complexity and preference for slides of the physical environment and (2) to test the hypothesis that the content of slides (in particular, whether nature or urban) will influence preference, independent of the rated complexity, 88 Ss were asked to rate 56 slides, both for preference and for complexity. Based on dimensional analyses, a nature and an urban dimension were identified. Three major results were obtained: (1) Nature scenes were greatly preferred to urban scenes (p < .001). (2) Complexity predicted preference within the nature domain (r = .69) and within the urban domain (r = .78). (3) Complexity did not account for the preference for nature over urban slides; the greatly preferred nature slides were, in fact, judged on the average less complex than the urban slides. The possibility is raised that the domain-specific character of the preference/complexity relationship found in this study may be general; that is, it may not be a special property of environmentally generated arrays.
Article
In order to investigate the effects of foliage plants on the thermal environment and comfort inside a room, experiments were carried out in two rooms with the same size in winter. Foiiage plants used in the experiments were Schefflera arboricola "Hong Kong" and Dracaena fragrans "Massangeana". In our previous experiments, the former showed the highest transpiration rate and the latter showed little transpiration. The following three experiments were performed. In the experiment R, S. arboricola "Hong Kong" plants were placed in line at the southern end in one room and no plant was placed in the other room. In the experiment R, S. arboricola "Hong Kong" plants were placed in line at the southern end in one room and D. fragrans "Massangeana" plants were placed in line at the southern end in the other room. In the experiment (D, S. arboricola "Hong Kong" plants were placed in line at the southern end in one room and interspersed in the other room. In the experiment (D, S. arboricola "Hong Kong" in line at the southern end in the room brought about an increase in air temperature of about l.S°C and an increase in relative humidity of more than 20%. In the experiment c, relative humidity in the room with S. arboricola "Hong Kong" in line at the southern end was 20% higher than that with D. fragrans "Massangeana". This effect is considered to be caused by higher transpiration of S. arboricola "Hong Kong". In the experiment (D, S. arboricola "Hong Kong" interspersed in the room showed the same increase in relative humidity as S. arboricola "Hong Kong" in line at the southern end in the room. Furthermore, MRT and PMV was calculated from the measured data. The MRT showed some difference between the two rooms in the experiment c and the experiment (3), but there was little difference between the PMV of the two rooms in the three experiments.
Article
In this study, three experiments were performed in order to investigate the effect of ornamental foliage plants on visual fatigue caused by visual display terminal operation. Visual fatigue was evaluated as critical flicker fusion frequency (CFF). Four students served as subjects in each experiment.The experiment (1) was carried out to examine the reduction of visual fatigue by viewing plants during visual display terminal operation. As the results, the CFF of the subjects in case of viewing plants was higher than that in case of viewing no plant. Especially, the difference of the CFF of the subject A was 9.3%.The experiment (2) was carried out to examine the recovery of visual fatigue by viewing plants after visual display terminal operation. As the results, the CFF of the three subjects except A increased in case of viewing plants and decreased in case of viewing no plant. The differences of the CFF of the subjects B and D were 4.6% and 3.6% respectively.The experiment (3) was carried out to determine whether difference in kinds of plants could bring about difference of the recovery of visual fatigue. As the results, average of the CFF of the subjects in case of viewing Schefflera arboricola “Hong Kong”, Cupressus macrocarpa “Gold Crest” and no plant decreased by 2.7%, 3.1% and 6.0% respectively, while average of the CFF of the subjects in case of viewing Dracaena fragrans “Massangeana” showed an increase of 0.6%.
Article
In the present study, in order to investigate the psychological effect of ornamental foliage plants on human being, the authors carried out the following two experiments.The experiment (1) was the evaluation of the impression of ornamental foliage plants. The authors obtained the information about the impression of sixteen kinds of ornamental foliage plants through questionnaires from one hundred and two students (seventy-eight male and twenty-four female) who served as subjects. As the results, the ornamental foliage plants which were evaluated as “restful” were Cupressus macrocarpa “Gold Crest”, Ficus benjamina “Rich” and Dracaena fragrans “Massangeana”. The ornamental foliage plants which were evaluated as “refreshing” were Chrysalidocapus lutescens and Dracaena fragrans “Massangeana”.The experiment (2) was the psychological rating of the rooms with ornamental foliage plants by means of semantic differential method. Sixteen types of rooms without plants or with ornamental foliage plants were rated by sixteen students (eight male and eight female) using twenty-two SD scales and factor analysis was performed. As the results, the first factor “evaluation”, the second factor “activity” and the third factor “energy” were extracted by the factor analysis. The rooms with plants were evaluated higher than the rooms without plants in the first factor “evaluation” and the second factor “activity”. As for the arrangement of plants, the rooms with plants interspersed in the room were evaluated a little higher in the first factor “evaluation” than the rooms with plants in line inside the window.
Article
VDT作業によるテクノストレス (主として視覚疲労) が緑を見ることによって解消されるかを実験的に究明した。その結果, パーソナルコンピュータによるVDT作業を一定時間行わせた後に鉢物の緑遠景の樹林, 屋上の芝生などの緑を見せることによって, 無刺激条件 (何もしない), 模造品の緑を見せるなどに比べて, フリッカー値の低下 (率) は著しく抑制される。いうならば, 視覚疲労が明らかに緩和, 回復されることが明らかとなった。
Article
This article investigates the direct and indirect effects of windows in the workplace onjob satisfaction, intention to quit, and general well-being. The impact of three specific influencing mechanisms are examined: general level of illumination, sunlight penetration, and view. The extent to which these environmental features might moderate the negative consequences of job stress is investigated. The sample consisted of 100 white-and blue-collar workers who were employed in a large wine-producing organization in the Mediterranean region of Southern Europe. The results showed a significant direct effect for sunlight penetration on job satisfaction, intention to quit, and general well-being. A view of natural elements (i.e., trees, vegetation, plants, and foliage) was found to buffer the negative impact of job stress on intention to quit and to have a similar, albeit marginal, effect on general well-being. No effects for general level of illumination were found.
Article
Window size preferences were studied in two experiments using a 1/12 scale model. In the first experiment, subjects viewed small-to medium-sized offices. The experiment showed that window preferences are affected by room size. Preferred window size is not a constant proportion of wall size. Rather, a larger proportion is preferred for smaller rooms. Second, the experiment showed that scenes perceived as more beautiful lead to larger preferred windows. Third, office work experience of subjects had no effect on preferences. Experiment 2, which incorporated several changes, confirmed all three of these findings. In addition, this experiment showed that window size preferences are also affected by the type of the room. Subjects viewing the same model preferred smaller windows for a computer work room than for an office.
Article
presents some of the findings regarding the impact of mild positive affect on thinking and motivation / explores the processes underlying them and the circumstances under which they are likely to be observed / focus is on decision making, but in order to understand affect's influence on decisions, it is helpful to consider its impact on cognitive organization (or the way material is thought about and related to other material) and on motivation (PsycINFO Database Record (c) 2012 APA, all rights reserved)