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Previously studies have shown that nature improves mood and self-esteem and reduces blood pressure. Walking within a natural environment has been suggested to alter autonomic nervous system control, but the mechanisms are not fully understood. Heart rate variability (HRV) is a non-invasive method of assessing autonomic control and can give an insight into vagal modulation. Our hypothesis was that viewing nature alone within a controlled laboratory environment would induce higher levels of HRV as compared to built scenes. Heart rate (HR) and blood pressure (BP) were measured during viewing different scenes in a controlled environment. HRV was used to investigate alterations in autonomic activity, specifically parasympathetic activity. Each participant lay in the semi-supine position in a laboratory while we recorded 5 min (n = 29) of ECG, BP and respiration as they viewed two collections of slides (one containing nature views and the other built scenes). During viewing of nature, markers of parasympathetic activity were increased in both studies. Root mean squared of successive differences increased 4.2 ± 7.7 ms (t = 2.9, p = 0.008) and natural logarithm of high frequency increased 0.19 ± 0.36 ms(2) Hz(-1) (t = 2.9, p = 0.007) as compared to built scenes. Mean HR and BP were not significantly altered. This study provides evidence that autonomic control of the heart is altered by the simple act of just viewing natural scenes with an increase in vagal activity.
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Eur J Appl Physiol
DOI 10.1007/s00421-012-2318-8
The eVects of views of nature on autonomic control
V. F. Gladwell · D. K. Brown · J. L. Barton ·
M. P. Tarvainen · P. Kuoppa · J. Pretty ·
J. M. Suddaby · G. R. H. Sandercock
Received: 20 July 2011 / Accepted: 7 January 2012
© Springer-Verlag 2012
Abstract Previously studies have shown that nature
improves mood and self-esteem and reduces blood pres-
sure. Walking within a natural environment has been sug-
gested to alter autonomic nervous system control, but the
mechanisms are not fully understood. Heart rate variability
(HRV) is a non-invasive method of assessing autonomic
control and can give an insight into vagal modulation. Our
hypothesis was that viewing nature alone within a con-
trolled laboratory environment would induce higher levels
of HRV as compared to built scenes. Heart rate (HR) and
blood pressure (BP) were measured during viewing diVer-
ent scenes in a controlled environment. HRV was used to
investigate alterations in autonomic activity, speciWcally
parasympathetic activity. Each participant lay in the semi-
supine position in a laboratory while we recorded 5 min
(n= 29) of ECG, BP and respiration as they viewed two
collections of slides (one containing nature views and the
other built scenes). During viewing of nature, markers of
parasympathetic activity were increased in both studies.
Root mean squared of successive diVerences increased
4.2 §7.7 ms (t= 2.9, p= 0.008) and natural logarithm of
high frequency increased 0.19 §0.36 ms2Hz¡1 (t=2.9,
p= 0.007) as compared to built scenes. Mean HR and BP
were not signiWcantly altered. This study provides evidence
that autonomic control of the heart is altered by the simple
act of just viewing natural scenes with an increase in vagal
Keywords Environment · Nature · Cardiovascular ·
Autonomic control · Vagal activity
Nature has wide ranging positive eVects, but the mecha-
nisms of these eVects are not understood, particularly at a
physiological level. Cohort study data show that viewing
natural landscapes has positive beneWts including:
improved general health perception (Moore 1982); reduced
need for pain relief (Ulrich 1984; Diette et al. 2003; Lechtzin
et al. 2010); improved concentration and attention (Berto
2005); improved cognition (Berman et al. 2008); and
improved self-esteem and mood (Pretty et al. 2007; Barton
et al. 2009).
Meta-analyses (Barton and Pretty 2010) and systematic
reviews (Bowler et al. 2010; Thompson Coon et al. 2011)
demonstrate the eYcacy of exposure to nature in improving
psychological well-being, but there is a paucity of studies
examining physiological eVects (Bowler et al. 2010), possi-
bly due to the diYculties of recording high-quality physio-
logical data outdoors. In addition, to date laboratory studies
of viewing natural scenes prove inconsistent (Bowler et al.
2010). When participants viewed slides of rural or built
scenes there were no signiWcant diVerences in heart rate
(HR) responses (Ulrich 1981). When exposed to a stressor
(elevating HR and blood pressure (BP)) prior to viewing
videos of diVerent environments, natural views were
deemed more ‘restorative’ because they elicited more rapid
Communicated by Susan A. Ward.
V. F. Gladwell (&) · D. K. Brown · J. L. Barton · J. Pretty ·
J. M. Suddaby · G. R. H. Sandercock
Department of Biological Sciences, Centre for Sport and Exercise
Science, University of Essex, Wivenhoe Park,
Colchester CO4 3SQ, UK
M. P. Tarvainen · P. Kuoppa
Department of Applied Physics, University of Eastern Finland,
P.O. Box 1627, 70211 Kuopio, Finland
Eur J Appl Physiol
returns to baseline HR (Ulrich et al. 1991; Laumann et al.
2003) and BP (Chang et al. 2008). When treadmill exercise
was incorporated while viewing slides, BP was lower after
a 5-min recovery period after viewing slides depicting natu-
ral scenes when compared with slides depicting built envi-
ronments (Pretty et al. 2005).
To try and understand the physiological eVects of nature,
one area of interest is the control of the autonomic nervous
system (ANS). The ANS is important in the maintenance of
homeostasis and also in normal and stress–responsive phys-
iology. One way of investigating ANS control is studying
heart rate variability (HRV). HRV is a well-established
non-invasive tool which gives an indication of the changes
in vagal and sympathetic control of the heart.
Walking or sitting in a natural (forest) environment has
previously been shown to lower HR and BP when com-
pared with a built environment control (Park et al. 2010).
Park and colleagues suggest that an increase in vagally
mediated HRV with simultaneous decreases in sympathetic
components is responsible for the observed reductions in
HR and BP. Another study with similar engagement with
natural environments showed that BP was reduced with
a trend to reduced urinary noradrenaline inferring that
this was driven by a decrease in sympathetic stimulation
(Li et al. 2011).
However, in the outdoor environment, it is diYcult to
control external factors including the weather. In addition,
other elements, including smells and sounds may have pos-
itive or negative inXuences on the ANS. To date, there are
only a handful of studies that have explored ANS (Park
et al. 2010; Li et al. 2011) and these have not been able to
elucidate whether the act of just viewing nature can alter
ANS function. Furthermore, these previous studies have
also included exercise which is likely to alter the physiolog-
ical responses.
This is the Wrst study to explore the underlying physio-
logical mechanisms of nature by isolating viewing
nature in a controlled environment and comparing the ANS
responses to viewing built environments. The use of a con-
trolled environment also allowed the recording of Wnger BP
continually, as well as respiration, both of which can inXu-
ence HRV measures.
Our hypothesis was that the simple act of viewing nature
would alter ANS control with vagal measures of HRV
enhanced during viewing nature compared with built views.
Following ethical approval from the University Ethics
Committee, 35 (22 females) volunteers (comprising staV
and students from the University (mean (SD): age 39.7
(12.1) years) were recruited following an electronic adver-
tisement. Six individuals were excluded due to taking med-
ication which interfered with HR (n= 1), irregular heart
rhythms (n= 4) or severe obesity prohibiting valid readings
(n= 1). All remaining participants (n= 29) were free from
known disease. Participants attended the University labora-
tory on one occasion.
All participants provided informed consent and com-
pleted a health questionnaire (PAR-Q). All testing proce-
dures were carried out between 09:00 h and 14:00 h in a
quiet room with a constant temperature of 22–23°C to stan-
dardise for potential eVects of time of day and temperature,
as recommended when conducting autonomic experiments
(Tukek et al. 2003). Participants were asked to abstain from
food for 2 h and caVeine for 12 h prior to the start of their
tests and not to undertake strenuous physical activity in the
previous 24 h, as such activities may inXuence autonomic
regulation (Sidery and Macdonald 1994; Stubbs and Mac-
donald 1995). A diary was kept to ensure compliance.
ECG (modiWed Lead II conWguration) and continuous
BP (Portapres, FMS, Finapres Medical Systems BV, The
Netherlands) were measured. In addition, respiratory rate
and depth were recorded using a respiratory belt transducer
placed around the lower part of the chest. This strap con-
tains a piezo-electric device that responds linearly to
changes in length induced by chest movement due to
breathing. Breathing rate and depth over each 5-min seg-
ment were analysed to ensure that there were no signiWcant
alterations in these parameters.
Participants rested in the semi-supine position to allow
their HR and BP to stabilise and remained in this position
for the rest of the experiment. All data were sampled at
1,000 Hz and collected by a Powerlab 8SP (Model ML785,
ADInstruments, UK), using Chart 4 software (ADInstru-
ments, UK).
Testing commenced after 15 min of rest to ensure stabi-
lisation of HR. Participants were shown two collections of
slides during the same session. One slideshow contained
natural scenes and the second set incorporated built or
urban scenes lacking greenery (Fig. 1). Participants were
asked to imagine they were in the environment. Slides were
projected on to a screen (1.8 m £1.8 m) situated in front of
the participant.
Half of the participants viewed the natural environment
set of slides Wrst followed by the built environment slides in
a randomised crossover design. The other participants
viewed the built slides Wrst. Ten minutes between the two
sets was allowed, with participants remaining quiet and still
in a semi-supine position whilst looking at a blank screen.
Each slideshow (18 slides) lasted for 5 min with each slide
shown for 17 s. Slides within a slideshow were always
shown in the same order. HR, BP and respiration measure-
ments were recorded for the whole of the 5 min whilst
viewing the slideshow.
Eur J Appl Physiol
Data analysis: heart rate variability
ECG data were analysed using Kubios HRV software
(Niskanen et al. 2004) ( Data for
each set of slides were analysed and averaged over the
5 min periods of viewing slides of either natural or built
environments. No aberrant or ectopic beats were identiWed.
RR intervals were then extracted from the ECG signal and
re-sampled at 4 Hz using cubic spline interpolation to pro-
vide equidistant time points. In the time domain, the mean
R–R interval and HR, standard deviation of RR intervals
(SDRR) and root mean square of successive diVerences
(rMSSD) were calculated as recommended (Task Force
1996). Data then underwent Fast Fourier transformation
(non-parametric) using Welch’s periodogram method. Data
were split into windows of a width of 256 s with an overlap
of 50%. The power spectrum was obtained by averaging
the spectra within these windows. Two spectral compo-
nents of the recording were analysed: low frequency (LF,
0.04–0.15 Hz) and high frequency (HF 0.15–0.40 Hz) spec-
tral power, in accordance with international guidelines
(Task Force 1996). HF provides an indication of parasym-
pathetic activity, whereas LF oscillations result from the
combined activity of both autonomic nervous system
branches (Task Force 1996).
Non-linear analysis was performed using Poincaré plot
analysis, a graphical representation of the correlation
between successive RR intervals with SD1 indicating short-
term variability (analogous to rMSSD and HF) and SD2
indicating overall variability (analogous to SDRR) (Bren-
nan et al. 2001).
Data analysis: blood pressure and baroreceptor sensitivity
Combined measurements of HRV and BP variability give
information on both parasympathetic and sympathetic ner-
vous system activity. Systolic, diastolic and mean BP val-
ues were detected from the measured BP signal for each
heart beat. Systolic BP (SBP) and RR time series were used
in baroreceptor sensitivity (BRS) estimation (the BP value
was as compared to the following RR interval). Both were
Wrst interpolated at 4 Hz and de-trended with smoothing
prior method. BRS values were estimated using two meth-
ods: multivariate autoregressive (AR) spectral estimation
Fig. 1 An example of the slides taken for the built slideshow (a, b) and from the natural slideshow (c, d). There were 18 slides in each slide show
with each slide shown for 17 s
Eur J Appl Physiol
method and sequence analysis. Power spectra were Wrst cal-
culated by Wtting a multivariate AR model of order 22 to
RR and SBP time series. AR coeYcients were then used to
calculate power, coherence and phase spectra (Di Rienzo
et al. 2001). BRS estimates were calculated from the spec-
tra using the frequency–domain alpha technique. Values
were calculated for LF (0.04–0.15) Hz and HF (0.15–
0.4 Hz). Spectrum values were calculated in 301 points
between 0 and 2 Hz and only where coherence was higher
than 0.5 and phase was below 0 were accepted to the sum
of spectrum power.
The sequence method was also used to estimate BRS
values. Sequences were detected from the original signals
where RR interval and SBP value both ascended or when
both descended at the same time for at least three consecu-
tive intervals. Minimum change that was accepted was
5 ms for RR and 1 mmHg for SBP. A regression line (RR
as a function of SBP) was Wtted to the detected sequences,
and then correlations between these variables were calcu-
lated (Pearson’s correlation coeYcient), and those with
r> 0.85 were accepted. The BRS value was then obtained
as the mean slope of the regression lines Wtted to all
accepted sequence points (Di Rienzo et al. 2001).
Data analysis: respiration
The respiratory trace was analysed oZine in Chart by look-
ing at cyclic variables and obtaining average cycle length,
and average of maximum peak height and average of peak
minimum height and average cycle height were calculated
(Table 2).
Statistical analysis
Paired ttests were used to statistically analyse the data for
the eVect of the two types of view (natural versus built)
with signiWcance set at p·0.05. Paired ttests were also
used to statistically analyse the data for the eVect of slide
show one compared with slide show two (irrespective of
type of view) with signiWcance set at p·0.05. All the data
given are normally distributed except for absolute values
for HF and LF (as assessed by Kolomogorov–Smirnov test
for normality). The eVect size was calculated using Cohen’s
dfor all physiological variables.
Twenty-nine participants were included in the analysis.
Mean HR, systolic BP (SBP) and diastolic BP (DBP) were
similar while viewing natural or built environment images
(Table 1). The eVect sizes for all these were very small
(drange 0.04–0.19) (Table 1).
There were no signiWcant diVerences in breathing depth
or cycle duration between the diVerent views (Table 2).
Time domain (SDRR, rMSSD), and non-linear (SD1)
indices of vagal outXow were all signiWcantly higher when
viewing natural versus built environments (Fig. 2; Table 2).
23/29 participants increased rMSSD whilst viewing nature
as compared to built views (Fig. 2). Following natural log
transformation of HF (lnHF), there was also a signiWcant
diVerence in lnHF between natural and built environment
views with 21/29 participants with increased lnHF whilst
viewing nature as compared to built views (Fig. 2). EVect
sizes for vagal indices were moderate (Table 3).
BRS values using AR analysis in the HF domain (BRS-
HF) were signiWcantly greater during viewing natural
scenes compared to built scenes (Table 4). BRS values
obtained using sequence analysis (BRS-UP) were signiW-
cantly higher while viewing natural environments, whilst
BRS-combined was also close to statistical signiWcance
(p=0.06) (Table4). EVect sizes for BRS variables are
classed as small to moderate (Table 4).
An analysis of order eVect was undertaken to ensure
responses were due to the images on the slides and not
which set of slides was presented Wrst. No signiWcant diVer-
ences were found for any parameters.
Previous experimental work suggests exercising in nature
improves mental health, in particular mood and self-esteem
(Pretty et al. 2005, 2007; Barton et al. 2009; Barton and
Pretty 2010; Bowler et al. 2010; Thompson Coon et al.
Table 1 Cardiovascular variables during the two diVerent slide view-
ings: nature and built
Data are shown as mean (SD); n= 29. EVect size is also shown
(Cohen’s d)
HR mean heart rate, SBP systolic blood pressure, DBP diastolic blood
Nature Built SigniWcance EVect size
HR (bpm) 62.6 (9.2) 62.6 (9.3) 0.9 0.04
SBP (mmHg) 116.4 (10.3) 118.4 (11.0) 0.15 0.19
DBP (mmHg) 59.0 (11.0) 59.8 (9.0) 0.25 0.08
Table 2 Respiratory values during the two diVerent slide viewings:
nature and built
Data are shown as mean (SD), n=29
Nature Built SigniWcance
Duration of 1 breathing cycle (s) 4.4 (0.8) 4.2 (0.8) 0.12
Average minimum peak height ¡1.1 (2.1) ¡1.3 (1.6) 0.27
Average maximum peak height 3.3 (2.9) 3.1 (2.5) 0.23
Average cycle height 4.4 (3.0) 4.4 (3.1) 0.89
Eur J Appl Physiol
2011). However, fewer studies report physiological
responses (Bowler et al. 2010) and the underlying physio-
logical mechanisms involved in viewing nature alone are
unclear. Within a laboratory setting, previous studies have
measured HR (Ulrich et al. 1991; Laumann et al. 2003) and
blood pressure volume (Chang et al. 2008) after inducing
stress Wrst to alter baseline values. The nature views
appeared to have a restorative eVect with greater decreases
towards baseline values after the stressor when viewing
nature environments as compared to viewing built environ-
ments. In addition, following an outdoor walk in nature,
urinary noradrenaline levels were found to be lower versus
a built walk (Li et al. 2011). However, all of the previous
papers have inferred that changes in physiological mea-
sures are likely to be induced by the ANS, but have not
measured ANS control using established methods. Only
one previous study has explored the role of the ANS using
HRV, and this was conducted whilst the participants were
exposed to real environments (Park et al. 2010). Although
real environments allow investigations to be ecologically
valid, it makes it more diYcult to undertake a well-con-
trolled study to investigate ANS mechanisms. Our study is
the Wrst to explore ANS control in a controlled environ-
ment, also enabling BP and respiration to be measured
In the current study, alterations in cardiovascular auto-
nomic control (in particular vagal activity) were measured
by the use of well-established non-invasive measures of
HRV and BRS. HRV and BRS-HF increased signiWcantly
during the viewing of nature compared with built environ-
ment scenes, suggesting increases in vagal activity. This
suggests that the simple act of viewing nature may induce
changes in autonomic control, in particular vagal activity.
In the current study, the increases in vagal activity are pres-
ent without prior exercise or stress inducing components, or
the additional factors that are present in a real environment.
The real environment and prior exercise may act synergisti-
cally with the nature views to produce greater physiological
eVects. However, in this study, we wished to explore, in a
Fig. 2 Individual comparisons of responses to built and nature views
for arMSSD, bSDRR, clnHF, dlnLF, eSD1, fSD2 (see text for
explanation of abbreviations). Built is shown on the left of each graph
with nature on the right
Table 3 Measures of HRV during the two diVerent slide viewings:
nature and built
Data are shown as mean (SD), n= 29. The absolute values for HF are
1,039.7 (with range 193.8–3,516.8) ms2Hz¡1 and 868.1 (range 172.9–
2,629.7) ms2Hz¡1 collected during viewing natural and built scenes,
respectively. The absolute values for LF are 709.2 (with range 158.1–
2,268.9) ms2Hz¡1 and 970.0 (range 51.4–7,443.8) ms2Hz¡1 collected
during viewing natural and built scenes, respectively. All the data
shown are normally distributed except for absolute values for HF and
LF (as tested by Kolomogorov–Smirnov test for normality). EVect size
is also shown (Cohen’s d)
SDRR standard deviation of RR interval, lnLF natural log of low fre-
quency spectral power (0.04–0.15 Hz), SD2 long-term variability
Poincare plot, rMSSD root mean squared of successive diVerences,
lnHF natural log of high frequency spectral power (0.15–0.4 Hz), SD1
short-term variability Poincare plot
Nature Built SigniWcance EVect size
Overall variability
SDRR (ms) 54.2 (16.0) 49.0 (13.2) 0.001 0.35
lnLF 6.36 (1.0) 6.32 (0.7) 0.8 0.04
SD2 67.0 (19.1) 60.3 (16.1) 0.008 0.38
Vagal mediated
rMSSD (ms) 50.6 (22.1) 46.4 (18.6) 0.008 0.32
lnHF 6.65 (0.8) 6.45 (0.8) 0.007 0.23
SD1 35.8 (15.6) 32.8 (13.1) 0.008 0.21
Table 4 Measures of BRS during the two diVerent slide viewings:
nature and built
Data are shown as mean (SD), n= 29. These measures generally reXect
vagally mediated changes. EVect size is also shown (Cohen’s d)
BRS baroreceptor sensitivity, BRS-HF derived from cross-spectral
analysis, BRS-UP and BRS-combined derived from sequence analysis
Nature Built SigniWcance EVect
BRS-HF (ms mmHg¡1) 23.1 (11.9) 20.5 (8.5) 0.008 0.25
BRS-UP (ms mmHg¡1) 15.9 (9.6) 12.9 (5.1) 0.048 0.39
(ms mmHg¡1)
14.5 (5.6) 13.7 (5.6) 0.06 0.15
Eur J Appl Physiol
controlled environment, the underlying physiological
mechanisms of the eVects of nature views without the eVect
of prior exercise or stress.
It is likely that the views of nature induced relaxation
and indeed Park et al. (2010) suggest the augmented vagal
activity they observed while participants were engaged
with nature was due to relaxation. Relaxation is also pro-
posed to occur via stress reduction (Ulrich 1981; Ulrich
et al. 1991) or alterations in attentional capacity (Kaplan
and Kaplan 1989). In earlier studies, EEG has shown an
increase in alpha waves (suggesting relaxation) when view-
ing nature, but they did not deWne particular areas of the
brain (Ulrich 1981). Anecdotally, our participants reported
a preference for viewing the natural scenes and feeling
more relaxed. Relaxation can cause changes in breathing
rate and depth and these in turn can aVect HRV. In the cur-
rent study, due to the controlled environment, breathing
rate and depth were able to be measured and were not sig-
niWcantly diVerent between the views with a breathing fre-
quency at 0.24 Hz. We did not control breathing frequency
as previous papers show that HRV measures are not signiW-
cantly aVected by controlled or free breathing if HR is
within normal ranges (Patwardhan et al. 1995; BloomWeld
et al. 2001). We do understand the need for breathing rate
not to be signiWcantly diVerent for a participant in the two
conditions. In practical terms, we believe that in this study
asking participants to breathe to a metronome may have
caused a distraction from viewing the scenes and thus
altered the physiological eVects of viewing.
The rigorous application of established autonomic mea-
sures in a controlled environment advances existing physio-
logical research in this area. The controlled environment
allowed the act of viewing natural environments to be iso-
lated and eliminated other factors that may alter physiology
when humans are exposed to built or natural environments.
These include potentially negative factors, such as noise,
air pollution or potentially positive factors, such as natural
sounds and phytoncides (Li et al. 2011). The authors of pre-
vious studies suggest that the eVects in cardiovascular
markers are caused by walking or being surrounded by the
relaxing forest environments (Park et al. 2010) with the nat-
ural fragrance of trees (phytoncides) contributing to the
reduction in BP and attenuation of biomarkers in the blood
and urine, including noradrenaline (Li et al. 2011). They
suggest BP reductions may be due to a decrease in sympa-
thetic activity and an increase in parasympathetic activity.
The exercise component itself could contribute to some of
the reduction in sympathetic activity and increase in para-
sympathetic activity, although the BP reductions were
greater following nature walks, suggesting an additional
eVect of nature.
Previous experiments that have used the controlled envi-
ronment of a laboratory have generally used prior exposure
to a stressor to increase participants’ HR and BP before
examining recovery and have not measured ANS activity.
Improved recovery of HR (Ulrich et al. 1991; Laumann
et al. 2003) and BP (Chang et al. 2008) while viewing natu-
ral scenes after exposure to a stressor has led to nature
being regarded as ‘restorative’. In contrast to the previous
experiments, we were interested in exploring the direct
eVects of viewing nature on HRV and BRS at rest without
the addition of exercise or a stressor to establish the physio-
logical mechanisms of viewing nature alone. Unfortu-
nately, the physiological changes are less dramatic when
changes are investigated from baseline values, especially in
a well-controlled experiment, where the participant should
be relaxed prior to taking part in the experimental condi-
tions. At rest, the body aims to maintain homeostasis, and
large decreases were not expected in the already low, rest-
ing values in our study for HR (62 beats per minute) or BP
(117/59 mmHg) on exposure to nature. It would be highly
unlikely and unusual for an individual’s HR to drop by
5 beats per minute from this level, which would be needed
to show a signiWcant diVerence. However, it may be
expected that HR would decrease, in conjunction with the
increase in HRV, but this was not the case. This is unsur-
prising since mean HR cannot reXect the oscillating inXu-
ences on cardiac vagal neurones (Gilbey et al. 1984). In a
previous study involving respiratory training, HRV was
measured alongside other markers of vagal activity (includ-
ing measures of HR recovery following exercise), and all
markers indicated that vagal activity increased despite no
signiWcant change in HR (Hepburn et al. 2005). However,
HRV is a sensitive indicator of ANS function and in partic-
ular vagal activity and the utilisation of such measures adds
to existing laboratory data (Ulrich 1981; Ulrich et al. 1991;
Laumann et al. 2003; Berto 2005; Pretty et al. 2005; Ber-
man et al. 2008; Chang et al. 2008) as it provides, for the
Wrst time, information on how viewing nature aVects the
ANS and the interaction of HR and BP in terms of barore-
ceptor activity. However, for comparisons to be made
within participants, respiratory frequency and depth should
not be signiWcantly altered, as was the case in our study.
Increases in HRV measures may have an important
physiological relevance, despite the lack of signiWcant
changes in HR and BP. The alterations that are seen in
lnHF, rMSSD and SD1 give an indication of the degree of
inXuence on cardiac vagal neurones at respiratory frequen-
cies (Task Force 1996), i.e., it does not necessarily imply
that there is an increase in overall vagal tone, but suggests
increased vagal phasic activity. AVerent input from higher
centres and/or from feedback mechanisms (e.g. barorecep-
tors and chemoreceptors) induce changes in vagal neurone
outXow from the nucleus tractus solitarii (NTS). Increases
in vagal neurone outXow can be caused by an increase in
synaptic excitatory input to cardiac vagal neurones; or a
Eur J Appl Physiol
decrease in inhibition elicited by inspiratory drive; or both.
At rest, during normal breathing (as was the case in our
study), if there is an increase in vagal neurone excitability
(maybe via baroreceptor inXuence), R–R interval will
increase. This can be followed by a rebound inhibition of
these vagal neurones by inspiratory drive, decreasing R–R
interval to a greater extent, giving augmented HRV values,
but with an unchanged mean HR. This is likely to be the
case in our participants. The baroreceptors may play a role
in maintaining homeostasis as BRS is elevated during
nature views.
The cause of the increase in vagal excitability is very
interesting, and it is likely that the nucleus ambiguus con-
taining the vagal neurones is inXuenced by other areas of
the brain. Some of the images that we used in our current
study were examined for how aversive and uncomfortable
they were by examining their spatial frequency properties
(Fernandez and Wilkins 2008). Our nature images were
found to be more pleasant and less aversive. Interestingly,
in a recent study which used MRI during natural and urban
views diVerent areas of the brain were stimulated depend-
ing on which scenes were viewed (Kim et al. 2010). The
visual cortex was stimulated more in the urban views than
the natural views. These Wndings may suggest that in part,
the increase in vagal activity may be because the nature
images have less impact on the visual system, with nature
images being able to be processed more eYciently and
inducing diVerent changes within the visual cortex than
images of built slides. The inXuence of visual cortex and
other areas of the brain (maybe the frontal cortex) are likely
to be mediated via the left insular cortex, a region contain-
ing neurones that excite cardiac vagal neurones selectively
via the amygdala as increases in amygdala excitation have
been associated with inhibition of parasympathetic activity
(Thayer and Lane 2009).
Although the results show alterations in HRV measures
for both overall variability and what is considered to be
vagally mediated variability, there were no signiWcant
changes in HR and BP, which may be considered as impor-
tant functional measures. Without signiWcant alterations in
HR and BP, this may limit the conclusions that can be
drawn from the present study.
A further limitation of the study is that although there
are statistically signiWcant diVerences between the two
views, inter-individual diVerences exist in responses to the
slides. This might be due to a lack of continuous engage-
ment from the participants with the projected scenes
throughout the whole slideshow, i.e., the participants’
minds wandering. Alternatively, participants may have
varying aYnities to nature which results in diVerent
responses towards the scenes viewed in this study.
Future studies are needed to explore the mechanisms and
in particular physiological changes that occur in response to
nature, taking into consideration individual diVerences and
aYnity to nature. This study provides an important basis to
start to derive explanations of changes that are seen in
cohort and epidemiological studies.
This study shows for the Wrst time that the simple act of
viewing natural scenes, without the additional factors found
in a real environment, may induce changes in autonomic
control via increases in vagal modulation. The increases in
vagal activity are evident without prior exercise or stress
inducing components.
Acknowledgments V.F. Gladwell is an ESRC research fellow (pro-
ject number RES-064-27-0019). D.K. Brown is supported by a BHF
studentship Grant FS/10/32/28204. The study was also supported by
Academy of Finland (project number 126873).
ConXict of interest None.
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... This theory posits that natural features, in contrast to human-made features, do not require direct attention, thereby providing a calming backdrop for relaxation and restoration [32]. Indeed, laboratory evidence has shown an increase in parasympathetic nervous activity and lowered heart rate when viewing images of trees [33,34], a preference for more 'natural' images [35], and a preference for green and blue hues (e.g., sky) and 'natural' compared to built scenes [32,36,37]. In fact, in a study exploring people's perceptions of apartment window views, views with maximum amounts of sky are perceived as most restorative [38]. ...
... This finding aligns with several studies showing associations with complementary outcomes including learning attainment, mental recovery, and graduation rates [46,49,55,56]. It appears that these results may be driven, in part, by the presence of trees, as found in other research [33,34]. Indeed, other research that found specific types of nature on school campuses, in particular trees and shrubs, were beneficial to students [48,49]. ...
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Exposure to nature views has been associated with diverse mental health and cognitive capacity benefits. Yet, much of this evidence was derived in adult samples and typically only involves residential views of nature. Findings from studies with children suggest that when more greenness is available at home or school, children have higher academic performance and have expedited attention restoration, although most studies utilize coarse or subjective assessments of exposure to nature and largely neglect investigation among young children. Here, we investigated associations between objectively measured visible nature at school and children’s behavior problems (attention and externalizing behaviors using the Brief Problem Monitor Parent Form) in a sample of 86 children aged seven to nine years old from 15 classrooms across three schools. Images of classroom windows were used to quantify overall nature views and views of specific nature types (sky, grass, tree, shrub). We fitted separate Tobit regression models to test associations between classroom nature views and attention and externalizing behaviors, accounting for age, sex, race/ethnicity, residential deprivation score, and residential nature views (using Google Street View imagery). We found that higher levels of visible nature from classroom windows were associated with lower externalizing behavior problem scores, after confounder adjustment. This relationship was consistent for visible trees, but not other nature types. No significant associations were detected for attention problems. This initial study suggests that classroom-based exposure to visible nature, particularly trees, could benefit children’s mental health, with implications for landscape and school design.
... Particularly, parasympathetic nervous activity is increased during exercise in nature and positive mood and satisfaction with life are positively associated with green exercise [10][11][12]. There is successive preliminary evidence at physiological [12][13][14][15], psychological [11,[16][17][18][19][20], biochemical [21,22] and social levels [12,20], which suggests that green exercise might have a useful role in primary and secondary prevention or treatment of chronic diseases. Notably, walking in forest environments has positive effects on blood adiponectin and on blood pressure [21]. ...
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Background: Exercise has indisputable advantages for people with chronic conditions. Engaging in physical activity within natural environments, known as green exercise, contributes to both physical and mental well-being. The aim of this study was to investigate the perceptions of people with chronic conditions and health professionals and the perceived facilitators and barriers to therapeutic green exercise. Methods: This was a qualitative study based on two focus groups. Ethical approval was received, and a thematic analysis was used to analyze the discussions. Results: Seven patients and eight health professionals participated in the study. The thematic analysis yielded thirteen main themes. Safety concerns and inadequate infrastructures were key barriers. Core facilitators were socialization, and multisensory exposure. Conclusions: Patients with chronic conditions and health professionals believe that green exercise improves physical activity engagement, and it would be beneficial if incorporated in the rehabilitation process. There are challenges to overcome to make therapeutic green exercise for people with chronic conditions more accessible.
... In both phrases T1 and T2, participants watched each video for five minutes, as research shows that a 5-minute video can induce positive physiological change [4,6,9]. Therefore, we selected this duration to keep the experiment short but with relevant results. ...
Conference Paper
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... An autonomic investigation recently reported that, by comparing viewing green and constructed landscapes, the parasympathetic function was induced while observing green images, whereas the sympathetic function found no differences between those two observations [44]. Additional research conducted within the same team discovered that visualizing green views before a stressor raised parasympathetic function in the recovery phase, as evaluated by vagus-mediated heart rate variability (the root mean square of the successive differences) [45]. ...
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Urban green spaces have been increasingly evidenced to not only improve human health (both body and mind) and well-being but also promote a sustainable way of living for citizens as well as cities. These positive health and sustainable advantages have even greater impacts when applied to people with disabilities, which can ultimately evaluate their quality of life in the long run. Unfortunately, people with disabilities receive less attention and tend to be disregarded in terms of equal access to public facilities, health-related services, and opportunities in society. Therefore, this article emphasizes the value of having green spaces within cities and acknowledges how people with disabilities gain the benefits through active and passive methods as well as direct and indirect means at the global, population, and individual levels. With that, this article argues that urban green spaces or the development of sustainable urbanism must prioritize and include people with disabilities in the planning process, as this inclusive population has the greatest potential for advancing public resources (e.g., environmentally, socially, and economically) and moving cities closer to being truly sustainable.
... In other words, it suggest that exposure to greenery, such as roadside trees, can have a positive impact on psychological health. Gladwell et al. found that exposure to views of nature has a positive effect on autonomic control, which can reduce stress and improve health (Gladwell et al., 2012). Our study provides an evidence on the positive effects of vision of roadside trees on reducing stress due to traffic noise. ...
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Introduction This study aims to investigate the interplay between roadside trees and pedestrians’ assessment of traffic noise and comfort. The study examines the potential effects of visual and design elements of roadside trees on the overall soundscape comfort. Methods The study design involves a systematic exploration of different conditions, encompassing traffic volume, distance from sound source, and tree density. For each combination, two experimental scenarios are created: (1) participants experience a binaural sound recording exclusively, and (2) participants experience the same binaural recording while concurrently immersed in a virtual reality (VR) video. Results Analysis of participants’ noise perception, measured using a quiet-noisy scale, reveals no significant disparity between conditions. This suggests that the mere presence of roadside trees does not necessarily lead to a perceived reduction in noise loudness. However, evaluation of sound intensity exposes a notable discrepancy between low and medium tree density levels. Furthermore, the study confirms the impact of roadside tree visibility, with scenes containing trees yielding more positive evaluations compared to sound-only scenarios. Remarkably, the absence of trees in the roadside scene garners consistent evaluations across both experimental conditions. Significantly, higher roadside tree density in conjunction with the combined sound and VR video condition prompts a more favorable assessment than the sound-only scenario. Discussion While the study indicates that roadside trees might not substantially mitigate perceived physical noise levels, their influence on the psychological well-being of urban inhabitants is considerable. The findings highlight that even though these trees may not overtly diminish noise, they hold substantial potential to enhance the overall comfort and well-being of city residents. This underscores the multifaceted benefits of integrating green spaces into urban design for improving the quality of urban soundscapes and residents’ experiences.
... Human contact with nature offers the advantage of a positive emotional state with reduced stress and increased relaxation, which can contribute greatly to mental recovery [8,[10][11][12]. Nature has been proven to positively influence human psychology [13,14]. Therefore, contact with the natural environment could alleviate the mental fatigue suffered by many people in modern society [15]. ...
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... For example, using a computer screen and pictures of urban and natural environments, Gladwell et al. (2012) found an increase in HRV associated with an increase in subjective relaxation when participants viewed nature environments compared to urban environments. Using a cave system to expose participants to a virtual Trier Social Stress Test followed by a recovery phase in a virtual forest showed a faster recovery measured by an increase in HRV in a virtual forest with sounds compared to a virtual forest without sounds, or a normal room (Annerstedt et al., 2013). ...
Objectives: To identify the impact of clinical risk adjustment models for evaluating pain medication consumption differences between private rooms and a multibed ward. Background: Views of nature are reported to reduce anxiety and pain for patients. This often leads to prioritizing large windows with views for patient rooms; however, it is not clear how other factors influencing pain (e.g., patient demographics) may confound evaluations of room design. Methods: We identified 1,284 patients at the University of Michigan undergoing thyroidectomy where patients recovered in one of the two locations: a private room with a view to nature or a multibed ward with no windows. We used pain medication data from the electronic medical record and risk adjustment models to evaluate pain medication consumption between the room types. Results: Private room patients did not use more pain medications when measured using unadjusted morphine milligram equivalents (18.3 vs. 15.3 mg, p = .06). Risk adjusting for age, gender, comorbidities, opioid history, and procedure subtype resulted in private room patients demonstrating higher consumption of morphine milliequivalents (17.5 vs. 15.5 mg, p < .01). In contrast, risk adjusting for age, gender, opioid history, and selected comorbidities estimated higher pain medication consumption for multibed ward patients relative to private rooms (16.27 vs. 15.51 mg, p < .05). Conclusion: Estimated differences of pain medication consumption for patients in differently designed rooms varied depending on the risk adjustment model. These findings underscore the importance of understanding appropriate clinical measurement and risk adjustment strategies to accurately estimate the impact of design, before applying research into practice.
This paper draws on Positive Psychology (Seligman, 2010) and attention to the Finnish context to explore ways of improving teacher wellbeing among primary schools in England.
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Subjects viewed sixty color slides of either (1) nature with water, (2) nature dominated by vegetation, or (3) urban environments without water or vegetation. The information rates of the three slide samples were equivalent. Measurements were taken of the effects of the slide presentations on alpha amplitude, heart rate, and emotional states. Results revealed several significant differences as a function of environment, which together indicate that the two categories of nature views had more positive influences on psychophysiological states than the urban scenes. Alpha was significantly higher during the vegetation as opposed to urban slides; similarly, alpha was higher on the average when subjects viewed water rather than urban content. There was also a consistent pattern for nature, especially water, to have more positive influences on emotional states. A salient finding was that water, and to a lesser extent vegetation views, held attention and interest more effectively than the urban scenes. Implications of the findings for theory development in environmental aesthetics are discussed.
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Lifestyles are increasingly characterised by sedentary behaviour, obesity problems, stress, mental ill-health and disconnection from nature. However, contact with nature has been shown to improve psychological health by reducing stress, enhancing mood and replenishing mental fatigue. In addition to providing a range of environmental services, greenspaces provide opportunities and incentives for ‘green exercise’ such as walking, cycling or horse riding. Visitor numbers indicate that many people already benefit from spending time in greenspaces, but little is known about the immediate impact of an acute exposure on their health and wellbeing. This study focuses on evaluating changes in self-esteem and mood after walking in four different National Trust sites of natural and heritage value in the East of England. The standardised measures of both self-esteem and mood were administered immediately pre- and post-activity. Self-esteem scores for visitors leaving the sites were significantly higher than those just arriving and overall mood also significantly improved. Feelings of anger, depression, tension and confusion all significantly reduced and vigour increased. Thus, the environment plays an important role in facilitating physical activities and helping to address sedentary behaviours. Walking, in particular, can serve many purposes including exercise, recreation, travel, companionship, relaxation and restoration. However, walking in greenspaces may offer a more sustainable option, as the primary reward is enhanced emotional wellbeing through both exposure to nature and participation in exercise.
The paper reports on a study that looks at the impact of a corrections environment upon prisoners through a process of monitoring inmate attendance at sick call clinic. Contrasting cell block designs and characteristics are compared on the basis of significant differential demands for health care services emanating from specific areas. Known psychological and physiological responses to situations perceived to be threatening provide the theory that health behavior may be used as one indirect measure of environmentally induced stress. Findings suggest there are architectural design features of the prison environment that provide basis of perceived threats to inmate safety and survival. Loss of privacy on several dimensions appears to be a critical environmental characteristic.
Three experiments were designed to test the hypothesis that exposure to restorative environments facilitates recovery from mental fatigue. To this end, participants were first mentally fatigued by performing a sustained attention test; then they viewed photographs of restorative environments, nonrestorative environments or geometrical patterns; and finally they performed the sustained attention test again. Only participants exposed to the restorative environments improved their performance on the final attention test, and this improvement occurred whether they viewed the scenes in the standardized time condition or in the self-paced time condition. Results are in agreement with Kaplan's [(1995). The restorative benefits of nature: Toward an integrative framework. Journal of Environmental Psychology, 15, 169–182] attention restoration theory, and support the idea that restorative environments help maintain and restore the capacity to direct attention.
The Task Force was established by the Board of the European Society of Cardiology and co-sponsored by the North American Society of Facing and Electrophysiology. It was organised jointly by the Working Groups on Arrhythmias arzd on Computers of Cardiology of the European Society of Cardiology. After exchanges of written views on the subject, the main meeting of a writing core of the Task Force took place on May 8-10. 1994, on Necker Island. Following external reviews, the tent of this report was approved by the Board of the European Society of Cardiology on August 19,1995, and by the Board of the North American Society of Facing and Electrophysiology on October 3, 1995.