Virtual View: statistics for experiment 3

In experiment three I wanted to see if adding movement to visual content had a bigger lowering effect on heart-rate and subjective stress then just using a still. And I wanted to know if variables like heart-rate and skin conductance could be restored to or below the baseline following a stress stimulus. Sound accompanied the visuals and I used the same soundtrack for both conditions.
The animation consisted of a main landscape layout with different animated elements over-laying that scene. The landscape consisted of a blue sky with white clouds slowly moving over it. Three hills with shrubs in different shades of green and a blue water body with a cream coloured shore. The animations were started mostly in sequence so there were just one or two animated elements to be seen. This is aside from the clouds and the waves on the water body, they were visible most of the time.staticAnimationStimulusAnimation still used in condition 2

Other animations are: big and small flocks of “birds” consisting of 150 and 5 “birds” respectively. They move in random directions within the frame. Blossom leaves flying from one side of the screen to the other. This animation also included a bee flying from one side of the screen in a slow, searching way. A final animation element are the butterflies. They flutter near the bottom of the centre of the screen and disappear after a random time span. The visuals are not realistic but simplified and based on the style of the old Japanese woodblock prints.
The sounds are inspired by nature but underwent a lot of computer manipulation. The sound is carefully synced with the imagery and movements on the screen.
In both conditions I measured subjective tension (7 point likert scale), heartbeats per minute, heart-coherence and skin conductivity. The experiment consisted of three stages: a baseline measurement (5 minutes), a cognitive stress task (around two minutes), the audio and visual stimulus part (5 minutes). Subjective tension was measured before the baseline measurement, after the stress task and after the stimulus. For a full description of the lab setup and experiment view the previous post.

The sample consisted of a total of 33 participants, more women then men (75% over 25%), this frequency was the same for both conditions. They were mainly recruited from the art centre where the experiment took place, there were a couple of students and some members from the general public. They were randomly assigned to each condition. The maximum age was 71, the minimum was 20 (mean 41,1). One dataset was corrupt so I ended up with 16 (mean age 39,6) participants in condition 1 (animated landscape) and 16 (mean age 42,7) in condition 2 (landscape still).

I’ve used SPSS 20 to calculate the statistics. I was curious if the heart-rate or heart-coherence would correlate with the subjective tension and/or the skin conductance. I could find very few significant correlations between the different variables. There are only significant connections between the different measurements of one variable. So the beats per minute (BPM) of the baseline measurement correlates with that of the cognitive stress task measurement and of the stimulus (landscape) measurement. The same is true for the Gavanic skin response (GSR) and the heart-coherence (HC). The only interesting correlation I found was a negative correlation between the baseline HC and the self reported tension (SRT) of the baseline and the stimulus. The could indicate that, assuming that heart-coherence is a measure of alert relaxation, perceived tension at the start and during the task the opposite of this alert relaxation state. But the correlation is weak (-496 and -501) so not much can be concluded from that.

Condition comparison
Before comparing conditions (with or without motion) I had to check if the stress stimulus had worked and if there was an effect for the audiovisual stimulus in general. Below you see an overview of the variables self reported tension (SRT), beats per minute (BPM), heart-coherence (HC) and galvanic skin response (GSR). The values for these variables are the mean values for the duration of the different parts of the experiment: Baseline (t1), cognitive stress task (t2) and stimulus (audiovisual material, both conditions) (t3). You can also see the expected direction of the variables. The significant values are printed in green.
From the table you can tell that there is a significant difference between the baseline measurement and the cognitive stress task on the one hand and between the stress task and the stimulus. This is true for BPM, GSR and self reported tension. All values rose during the stress task and decreased during the stimulus presentation. As those measures are strong indicators for stress this indicates that the stress task worked and the tension showed significant variation during the experiment. Heart-coherence shows no significant changes.
For the heart-rate there was even a significant lowering of the mean compared to the baseline. Indicating that the BPM was even lower the when participants entered the experiment.

Of course I wanted to test if there was a difference in the variables between conditions, that way I could see if animation was more effective then using only a static image. As you can see from the table there were no significant results for either of the conditions apart from the skin conductivity (GSR). The skin conductivity is a measure for arousal, the more aroused the higher the value. I would expect the GSR to be low at the start, high during the stress task and again low during the stimulus presentation. The GSR values for the stimulus presentation were significantly lower then during the stress task but they were still significantly higher then during the baseline measurement. This indicates that the GSR levels haven’t gone back to the baseline let alone become lower then the baseline state. This might be due to the fact that it takes more time for the skin activity to go back to normal. The response is slower than for heart-rate measurements.
We can see a reduction in heart-rate for both conditions with a bigger reduction in heart-rate for the animation condition. But neither of these changes are significant.
For the self reported tension we see a significant lowering in the tension from the higher values during the stress task and stimulus presentation. This means that people felt significantly less tense watching the landscape than during the stress task. The perceived tension was also lower in the animation condition than during at the start of the experiment though not significantly so. We don’t see this effect in the static condition. For this condition the baseline was lower and the effect of the stress stimulus was stronger. The overall variation was bigger. So you can’t really draw any definitive conclusions from this data other then that the landscapes reduced arousal in both conditions.

Overall lack of significance of many of the variables in either conditions may be caused by small the sample or it may indicate that there isn’t enough difference between the conditions for it to be significant. This might be caused by the way the stimuli were presented. For the sound we used a high quality active noise cancellation headphone. The impact of the sound was big. The screen image on the other hand was rather small (84,5 x 61,5 cm). The effect of the visuals might therefore be less strong in comparison with the high impact of the sounds.

I was of course also interested in the overall differences between the conditions, especially for the landscape stimulus. When comparing the different measurement moments for BPM we can see that in every moment the heart-rate in the static image condition is lower. So the participant in the first condition already started out with a much higher heart-rate. During the stress task the difference is even bigger and during the landscape presentation the differences have become smaller. I had expected that the heart-rate in the first condition would be lower but the differences are so big to begin with that you can’t draw any conclusions from it.

So does animation have a more positive effect on heart-rate, heart-coherence, skin conductance and self reported tension? I’ve looked at the interaction between all these variables and animation but on non of the variables the effect is significant. The major effects are on heart-rate. A bit to my surprise there are absolutely no effects on heart-coherence. In the first condition we see even a (non-significant) lowering of coherence during the animation. I’m therefore not going to use this value to drive my animation as was my original intention.

Scene comparison
While analysing I got curious to see if there are differences between the scenes of the animation and sound in condition 1 and 2. The animation and accompanying sounds can be divided into 10 different scenes. During the construction of the video I tried to incorporate various animation elements. They become visible one after the other.
I looked at the effects on mean heart-rate because it showed the most results. I wrote a script to calculate the mean heart-rate for every scene and for both conditions. The results are show in the graph below.

The variations between the scenes were not significant for the sound with still condition but they were at two points for the animated condition. You can view stills of the scenes below. There was a significant reduction in heart-rate of 4,8 between scenes 1 (mean 76,6) and 2 (mean 71,8). And a significant reduction in heart-rate between scenes 1 and 9 (mean 71, 5) of 5,1. This could suggest that more is happening to the participants in the animation condition and that animation has more potential for influencing the heart-rate of users.

Stills from the 10 different scenes

Virtual View: experiment 3 setup

For the design of the third experiment I got advice from Petra van der Schaaf, environmental psychologist. The main research question for this experiment is: does animation have added value in the restorative effect of natural stimuli?
So far I’ve tested the stimuli in sets containing 6 or 12 slides. The sound didn’t have a direct relation to the images. In this experiment I want to take the stimulus a step further.
I’ve been working on a program to produce randomised computer generated landscapes which consists of hills with shrubs and water. On top of that different animated elements are projected: clouds, flocks of birds, bees, butterflies, blossom leaves and waves on the water.
All the elements move at their own speed and behave in an appropriate manner. By pressing certain keys I can make the elements appear and disappear from the screen. That way I constructed a scenario which I recorded on video. The stimulus isn’t responding to the heart-rate yet because I want to gain insight into the effects of animation. This way I’m sure the whole group gets the same input. Sound artist Julien Mier continued to work on the sounds and made a score to match the images and direction of movement on the screen.


Due to lack of participants I had to reduce my conditions from 4 to 2, focussing on my own animation instead of also testing photo realistic versions. I worked with two groups: one group viewed the full video with accompanying sound. The other group got the full soundtrack but viewed only a still from the animation. That way I can test for the possible added effects of the animation element.

Subjective tension

The variables to be tested (the dependant variables) are:
Subjective feeling of tenseness. Participants score on the statement: “I feel tense.” This is measured on a 7 point likert scale going from not at all to the most tense ever. Beats per minute, inter beat interval (calculated from BPM), heart-coherence, heart-rate variability and Galvanic skin response. To measure the latter I used a separate device, the Mindtuner, which Malcolm from Heartlive kindly lend me. Two electrodes are placed around two fingers. A drawback is that the data is output in a separate file so I will have to do some data cleaning later to match the data with the events. But it will be nice to see how the skin conductivity behaves as this is a good indicator of stress.


The experiment starts with the measurement for subjective tenseness. This is followed by a 5 minute baseline measurement where people are asked to relax while looking at a black screen. After reading instructions participants engage in a cognitive stress task. They have to do subtractions within a limited time span. The more correct answers they give the shorter the time they have to do the calculations. There are 27 calculations in the task. Depending on the speed of the participants this task takes around 2 minutes. They then have to fill in the subjective tenseness questionnaire again. Then they watch either the five minute animation with sound or the still with sound. The experiment finishes after they have filled in the tension questionnaire.


The lab is located in a separate room at the BKKC office. Participants are seated at a table at 200 cm from a TV screen. The image shown is 84,5 x 61,5 cm. The sound was play using an active noise cancellation headphone (Bose Quiet Comfort 25). We choose these headphones because the building is located close to railway and a lot of office noises penetrate into the lab.

Many thanks go to BKKC for their support with the promotion and organisation of the experiment. Special thanks go to Hans and Laetitia. Without their help this experiment would have been impossible.

Virtual View: animation theory

The last weeks I’ve been working on designing and researching my third experiment. The next step will be to introduce animation and to study its effects. I was curious to see if there had already been research into the effect of different types of animation on stress reduction. Rather to my surprise I couldn’t find anything. It was hard to find any articles on animation what so ever…

My starting point was neurocinematics and psychocinematics. New fields of research on cognitive function during movie viewing. Attention is an important subject here. Then I found a journal dedicated to animation and found some very interesting information on the nature of animation and links between Eastern philosophy and religion and Japanese anime animation. That was very interesting for me. This way I can combine the visuals of Virtual View with Zen mediation and Buddhism, which I have been practising for almost 20 years. I realize now that my forests experiences on which Virtual View are based are rooted in my meditation practice. This is also what I want to convey with this installation.

In the next part I’ll summarise my findings and explain how I will test them in the animations I will make for my next experiment.

Even though the book chapter by Carroll and Seeley (draft version) is about Hollywood cinema it shed light on some aspects of my research. Because I want the users of Virtual View to have a relaxing and restorative experience attention is very important. How do I keep my users softly fascinated? Hollywood films capture attention by giving the viewers only just enough information using stylistic conventions. They also use variable framing: different techniques like camera movements and zooms to direct our attention. The theatre design with the big screen and darkened surroundings helps to minimize cognitive load. My interpretation of these thoughts is that a certain amount of abstraction can heighten attention. As can “camera” movement. These are things to play with. The actual installation should be set up to avoid distractions.

What interested me in the article by Torre is that animation can be expressive of itself. Motion can be transferred from one object to another to create surprising results and again, capture attention. As animation can be layered movement and transformation will have a cumulative effect and make anything possible in the way the impossible is possible in dreams. It will be nice to experiment with non-realistic events in the Virtual View animation.

The articles by Chow were a real revelation to me. His ideas of types of liveliness and holistic animacy fit perfectly with what I had in mind with Virtual View and what should be happening on the screen. For him primary liveliness is goal oriented and can been seen in for example Disney animations where a character causes all kinds of events. Secondary liveliness is unintentional and emergent. The sort of movement that can be seen in nature: the swarming of birds, waving of trees but also growth and shape changing. Where primary liveliness focuses our attention, secondary liveliness dilutes it, capturing our attention in a soft way. For Chow this wonder is linked to the ideas of Daoism and the concept of kami in Shintoism. They both promote respect for and connection with nature. He explains liveliness in computer graphics. Techniques like morphing, looping and Boids are good representatives of secondary liveliness. The eastern animation style called anime is also has good examples of this kind of liveliness. He shows some very nice examples of computer animation:

The Nintendo DS game Electroplankton

Chow also refers to old, Chinese maps of which the design is of the landscape elements was tightly regulated by rules. Rules are there to be bend so artists turned the maps into multi-perspective narratives. The maps are just beautiful, clear and mysterious at the same time.

Needham, J. (1962[1959]) from Science and Civilisation in China

Needham, J. (1962[1959]) from Science and Civilisation in China

Chow goes on to link animation with interactivity by looking at some pre-cinematic technologies. One of them is the handscroll, an ancient form of Chinese painting of which Along the River During the Qingming Festival is an example. When someone looks at a handscroll painting they interact with the picture emulating what we now call a camera pan. This way they include both time and space into the painting. I’m now considering capturing head movements as added interactivity to Virtual View. The animation will pan in the direction the head moves. This way people can expand they view and have richer, more varied experience.

The installation Along the River During the Qingming Festival

The last inspiration comes from an in depth article by Bigelow on the Japanese animation artist Miyazaki. She states that Miyazaki creates an aesthetic experience “… that invokes a Zen-Shinto pre-reflective consciousness of the inter- relation of the human with the tool and nature. It is a way of perceiving change in stillness…”. Bigelow sees a parallel between the state of mind of the artist and the state of selfless emptiness as it is described in Zen Buddhism and Shinto. It can create a state of wonder because this empty mind precedes concepts and naming. Miyazaki also expresses in his films the idea of the Shinto notion of kami in which all things have life spirit. This way of looking at reality makes way for a dimension of mystery and wonder to be discovered in nature.

Japanese anime is rooted in the art of woodblock printing of which I am a great fan. Miyazaki’s work is not photo-realistic but tries to capture the essence of reality that expresses interconnectedness. These things can, in his view, be lost in virtual reality, as it is often very technical and an industrialised method.

In my Virtual View animation I would like to evoke a sense of wonder by offering a non-photorealistic view that is lively in a way that reminds of real nature. I don’t want to replicate nature the way it is done in 3D virtual reality. It always seems dead to me, after reading these articles I understand why. The aesthetics will come from eastern art, which I love. The view will be a lively tableau with different kinds of computed animations which have there origin in natural phenomena. I will introduces panning to add extra space and “time” to the animation and to be able to add more, conscious interactivity in the prototyping stage. I will use these starting points to create a video of the animation which I will test in my next experiment. A description of that will appear soon on this blog.


Noel Carroll & William P Seeley. (2013) Cognitivism, Psychology, and Neuroscience,: Movies as Attentional Engines. Psychocinematics: The Aesthetic Science of Movies (draft copy).
Torre, D. Cognitive Animation Theory: A Process-Based Reading of Animation and Human Cognition. Animation: an interdisciplinary journal 9(1) p. 47-64
Chow, Kenny Ka-nin. The Spiritual—Functional Loop: Animation Redefined in the Digital Age Animation, March 2009; vol. 4, 1: pp. 77-89.
Bigelow, S. J. Technologies of Perception: Miyazaki in Theory and Practice. Animation March 2009 vol. 4 no. 1 55-75.
Chow, K. K. Toward Holistic Animacy: Digital Animated Phenomena echoing East Asian Thoughts. Animation July 2012 vol. 7 no. 2 175-187.
Shimamura, A. P. (2013). Presenting and analyzing movie stimuli for psychocinematic research. Tutorials in Quantitative Methods in Psychology, 9, 1-5

Information literacy

While designing experiment number three I bumped into the complexity of doing proper research. I realised I lacked some information literacy skills. Luckily the Open University (where I study psychology) offers free master classes. Last week one started on information literacy for researchers.
This has been very helpful for me to get a grip on the research process. Eye-openers for me were ways to clarify the research questions/tasks. All though I did have quite a clear view of what I want to research there are quite a few issues that need clarification. I’ve used a mind map to create an overview of the main and sub search questions at hand.


From that I’ve formulated clear search questions to streamline my search.

I also made a log of the key words I searched on and the results they generated. From that I can go on to studying and evaluating the relevant articles. I’ve got a template to fill in items like: Type of publication, research goal, theoretical focus and method. That way I get a nice overview of the articles I’ve studied.

I’ve been using Mendeley to collect my articles. You can organise them and mark important sections for easy summary. All content is stored in the cloud so I can read and highlight on any device.


But it becomes more and more clear to me why scientific research is so time consuming…

Virtual View: results experiment 2

The analysis of the second experiment has taken a long time. At first there appeared to be no significant results on any of the variables, except on the heart-rate during the cognitive stress task. So I consulted different people with a degree and research experience and asked for help. I’ve really learned a lot from them. They all have different approaches and ways of working so I’ve picked out all the good tips and insights. My thanks go to Sarah, Malcolm and Marie. The latter is a researcher at Tilburg University, her knowledge of statistics dazzled me. She is the one who recommended a different analyses which has yielded more significant results.

Research questions

My main questions for this experiment were: Which type of stimulus results in the most stress reduction and relaxation? And which stimulus produces the highest heart-coherence? As I want the values on that variable do drive my landscape animation.
To test these questions I used the following dependant variables: BPM, heart coherence,
later I introduced heart-rate variability calculated from inter-beat interval, self reported stress and self reported relaxation. These were measured during the baseline measurement, the cognitive stress tasks and the stimulus sets.
The independent variables are: stimulus set 1 with 12 landscape photographs and synthetic nature sounds, stimulus set 2 with more abstract landscapes styled by me with the synthetic natures sounds in the background. Stimulus set 3 consisted of 12 photographs of kitchen utensils and a soundtrack of someone preparing a salad. The expected direction of the variables will be explained below.


After struggling for some time with the non-significance of the variables in the different sets I discovered that the randomisation of the sets hadn’t been ideal. There were 33 participants who viewed the sets in 6 different orders. On top of that the group size per order was different. Some groups were only 4 participants, others 10. This is something I’ll have to take into account in my next experiment.
I used a repeated measures analyses. On my first, non-significant results, I used my baseline measurement as a covariate. Marie said that wasn’t the way to go. So I used just repeated measures where the baseline is just the first measurement, no covariates. And I did post hoc analysis (Bonferroni) to see the differences between the set results.
This is an overview of the results:
Results overview
Sarah made this clear lay-out of the research results compared to the expected results.
As you can see from the blue results the subjective stress measurements are significant compared to the baseline for all three stress tasks. For the first stress task (note this task isn’t connected to set 1, it is just the first task after the baseline measurement) the difference in heart-rate is significant during the stress task. There is also significant difference in HR during the landscape set. The kitchen utensil set heart-rate is also significant. Even though the heart-coherence is has the right direction non of the changes are significant. There are also no significant differences between the subjective relaxation questionnaires.

On Sarah’s recommendation I also looked at correlation between all the variables. That is very interesting as it reveals relationships between the variables. As the subjective relaxation questionnaire didn’t show any significant results I was curious to see how it correlates with the stress questionnaire. There should be a significant negative correlation between the two. And there is, it is especially strong for the baseline stress measurement and all relaxation measurements. On the other hand there was no correlation between subjective relaxation and heart-rate, a lowering of this value may be considered an indication of relaxation. All in all the relaxation questionnaire doesn’t give convincing results. There was a very strong correlation between heart-rate and heart-rate variability. In fact too strong, as Sarah pointed out they measure the same thing so it has no use including this variable in the results.

First set

As the stress stimulus was strongest the first time (view below) Marie advised me to do an analyses on the first set that was shown after the first stress task, independent of what kind of stimulus set it was. This was the distribution: set 1:    shown 11 times; set 2: 14; set 3: 8. The results from this analyses completely matched the other results. Heart-rate and heart-rate variability are significant (this is of course an average of all three sets shown), heart coherence and self reported relaxation were not. There was no interaction effect between the set shown and either the heart-rate or heart-rate variability which suggest that the order has no effects on the results.


Stimulus overview

I made some manual graphs to see the effects of the stimuli on heart-rate and heart coherence side by side. There is no significant difference between the pictures in the three sets. For me it is still nice to see the difference between the pictures. The graph is done manually in Photoshop.

Stimuli used


After getting advice from Malcolm  about the results he suggested I calculate heart-rate variability from the inter-beat interval values that I’d logged. Heart-rate variability is known to correlate well with stress (negative) and relaxation (positive). So that’s valuable information to add to the results.
I wrote a script in Processing to calculate and visualise the HRV for the whole experiment divided in a 5 second windows. The white line is the baseline measurement, the red lines are the stress inductions and the green lines are the audiovisual stimuli. You can tell from the image that the stress induction has some effect.

HRV results
Looking at my correlation table however there is only a significant negative correlation between the baseline subjective stress measurement and the HRV. Neither the other stress measurements nor the subjective relaxation measurements show any correlation.
It is hard to tell from the image but the photo realistic landscape set has a significant difference from the baseline measurement. The third set is almost significant (p = .054).


The first conclusion should be that the differences between the stimuli in the sets are small. There are significant* differences in average heart-rate between the sets (68,26 (baseline); 66.46* (set 1); 66.75 (set 2); 66.32* (set 3)). But the differences are really small. There is reduction in all the sets. Set 3, the kitchen utensils has the lowest average.  The set isn’t very stimulating which might explain the low heart-rate. This conclusion is also backed by the fact that the results from using only the first set shown are comparable to when working with the individual sets.
Heart coherence, which I want to use for driving the animation and to trigger the interaction with the installation showed that the styled landscapes with sounds had the highest heart coherence average but the results were not significant.  It does not seem a good measure for pure relaxation. Heart coherence is a difficult term but this description gives a good indication of the different aspects of this state: In summary, psychophysiological coherence is a distinctive mode of function driven by sustained, modulated positive emotions. At the psychological level, the term “coherence” is used to denote the high degree of order, harmony, and stability in mental and emotional processes that is experienced during this mode. (From The Coherent Heart p. 12, Mccraty, Rollin Ph et all, Institute of HeartMath). On page 17 of that document it states that: “In healthy individuals as heart rate increases, HRV decreases, and vice versa.” As HRV and coherence are closely linked the same is true for heart coherence. Even though heart coherence is much broader than relaxation is also encompasses activation of the parasympathic nervous system which is also a marker for relaxation. Important in heart coherence is the inclusion of positive emotions. This is what I try to evoke by using landscapes based on generally preferred landscapes.
The Virtual View installation should provide a relaxing distraction for people in care environments. Cognitive states that relate to this goal are soft fascination and a sense of being away as introduced in the Attention restoration theory (ART) by Kaplan and Kaplan. I’m guessing now that heart coherence might correlate with those cognitive states. This is something I will explore in the next experiment.

The stress task was perceived as stressful judging from the subjective reports. These findings are partly backed by the physiological data. Only the heart-rate of the first stress task differs significantly from the baseline. Our goal by introducing a stress task was to create bigger differences in heart-rate. For that to be successful the stress task should really produce stress. Although people reported feeling stressed we can’t measure it three times in a row. So for the next experiment I’ll work with 3 groups who will all get only one stress stimulus and one landscape stimulus.

All in all this experiment doesn’t prove that my styled landscapes with synthetic nature sounds create the most relaxation and heart-coherence but the results neither prove that they don’t. So for the next experiment I’ll continue with the styled landscapes and introduce animation.

Virtual View: design of experiment two

After conducting and analysing the first experiment some points of improvement emerged.

  • The differences in heart-rate between the sets weren’t significant so we want to create more extremes in heart-rate.
  • One group will get a heart-rate enhancing trigger and there will be a control group that won’t.
  • There was evidence of interaction with age for some of the variables so we want a more homogeneous age group to work with.
  • The experiment should be simplified, less sets and keep sounds the same for the landscapes sets. The duration of each stimulus was rather short so we want to try to double the amount of pictures in each set.
  • The control set should be neutral instead of negative.

It was clear that we want to introduce stress into the experiment. The target group are patients who visit hospitals. They are under stress a lot of the time. So we have to create a stress stimulus. Together with the students and a teacher from Avans Hogeschool we looked into some of the known possibilities for inducing stress. Our idea was to simulate a hospital through minor medical treatments. But we realized this will probably not work with our sample. They will be teachers with a background in nursing so taking blood pressure won’t upset them. I also discussed some options with Malcolm and Sarah. Showing parts of horror movies we considered to be too subjective. The best option is physical stress in the form of electro shock or ice-water. But this is out of our league. We don’t have the knowledge or experience to conduct an experiment like that.

Finally I settled for cognitive stress task in the form of calculations. As the stress task had to be repeated we needed a stimulus that would remain a challenge and induce some stress. Cognitive tasks have that ability. To keep it challenging there should be different levels to also keep it interesting for people whore a good at doing calculations. I made a little design.

cognitive Task Design

I had no idea how this design could be implemented in EventIDE. So I send my sketch to Ilia who programmed a nice interface. On the one hand the subtractions would get more difficult if your answers are correct. On top of that the allotted time will decrease if there are three correct answers in a row.

cognitive Task
The design is a 2×3 factorial with repeated measures. There will be three landscapes/objects with sounds and each of them will be experienced either with or without a stress stimulus preceding them.

Factor design

The flow of the experiment is as follows:
Design Experiment 2
Depending on how long it would take for the participants to complete the questionnaires the duration of the entire experiment will be around 30 minutes.

For me it was kind of hard to include the different questionnaires. We wanted to check experienced relaxation as we did in the first experiment. But we also wanted to know how much stress participants had experienced during the stress task. As these are opposite experiences I found it hard to find a place for both in the flow of the experiment. I finally settled for checking for self-reported stress right after the cognitive task and reporting relaxation after the landscape stimuli.

I would have loved to measure physiological stress data. Apart from heart-rate and heart-coherence there was no objective data. I discussed it with Malcolm. He kindly offered to lend me some of his equipment but we realized we just didn’t have enough time to implement it properly. So for now I just have to do with the heart-rate and self-reporting.

The dependent variables in this experiment are:
Heart-rate (beats per minute & inter beat interval)
Self-reported stress
Self-reported relaxation
The independent variables are:
Photo realistic landscapes & synthetic nature sounds
Styled landscapes & synthetic nature sounds
Kitchen utensils & kitchen sounds
Age and gender

The sample will consists of 30 + 30 participants older then 40 years without heart problems or heart medication.

Finally I could work on my own creations. This was the time for me to test some of my first sketches of the Virtual View landscapes. They are a combination of computer graphics made in Photoshop and computer generated images made in Processing. I combined them into bitmaps. As we wanted participants to be exposed longer to the stimuli we doubled the amount of pictures in each set from 6 to 12. The inspiration for the landscapes came from our literature study and the results of the first experiment. As an artist I wanted to see what I can leave out and still have a relaxing effect. I also experimented with different techniques to create the image elements.
styled landscape
The photo realistic images were chosen to resemble the styled image and have the same simple layout. The idea was to see it there would be a difference in relaxation and stress reduction effect between the computer graphics and the photographs.

Photo realistic landscape

Our initial idea for the neutral images was again to use interiors. We thought of general school areas. But as we were approaching the end of the year the teachers would be pretty highly strung and seeing pictures of the school might not be neutral for some. So we decided to use kitchen utensils. For the sound we used a recording of someone preparing salad.
The sounds to accompany the landscapes were produced and composed by Julien Mier.  For us this was also the first sketch of what Virtual View could sound like. Julien made some nice synthetic birds and bees. We worked towards a piece that was a mix of background noise, silence and unexpected animal noises. The sound was timed to the transitions between the images in the experiment. So every 20 seconds a new piece of sound was started with different accents. We used the same soundtrack for both landscape sets.

Virtual View: conducting the first experiment

Now that the research goal is clear, the stimuli are collected and the methods are clear and integrated in the EventIDE experiment it was time to look for participants. We needed at least 30 participants equally divided between men and women. Avans Hogeschool  has thousands of students and staff so we didn’t expect that to be a problem. The students wrote an inviting message on a digital notice board asking people to participate but only got two reactions. Enter the next strategy: walking up to anyone they met and just ask them to take part. That worked a lot better and most of the participants were recruited in this way. Some of the classmates were invited through text messages as well. In the end 33 participants took part, a mixture of students and staff.

Photo by Carlos Ramos Rodriguez

The students arranged the lab set-up and together we determined the protocol. The lab was a small classroom with a smart board with speakers. The students cleared most of the room, leaving it clutter free. The table was installed at a distance of 250 cm from the smart board. The projection was 154 x 108 cm. For the record I checked the sound levels of the different sets in the lab set-up with my decibel meter. They might have a strong influence so it is good to know at what average levels the sounds were played.

The sound level during the baseline measurement (no sounds were played) was 33 decibel. The autumn set with repetitive bird sounds 47 decibel, deflecting vistas with birds and running water sounds 43 decibel, hospital interiors with hospital waiting room sounds 48 decibel, standard preferred landscape with running water sounds 48 decibel and abstract landscape paintings with melodious bird songs 56 decibel.

Sketchup made by students Avans

The students lead the experiment, I came for the first couple of trials to taste the atmosphere and give some tips. At arrival people were welcomed and asked to turn off their phones. We also asked if they’d been to the bathroom. Because we use quite a lot of running water sounds and the experiment lasts around 20 minutes this might become an issue for people. We didn’t want them to get distracted because they needed to go to the bathroom and couldn’t. The sensor was placed on the earlobe. Participants were explained the course of the experiment and told that all data was anonymous and that they could leave at any time should they feel the need to end the experiment.

Participant id, age and gender were entered by the experiment leaders and then the participants were left alone with the stimuli and the questions.

As soon as the experiment was over the leaders would enter the lab for removal of the sensor and debriefing. Most participants were enthusiastic about the experiment and agreed to take part in the next experiment.

The next step is analysing the data, I can’t wait for the results!


Virtual View: research methods

How does one research the influence of landscape and sound on a human? Fortunately a lot of research has gone into finding out how people react to visual landscape stimuli. Most articles I’ve read made use of static pictures, some used video. As pictures can be found in abundance on the web and are easily stored and manipulated I chose static colour pictures as the main visual stimulus.

In most experiments natural landscapes are compared to urban environments with varying amounts of green. Almost always the natural and greener urban scenes have more positive effects on health and affect related variables compared to the urban environments. So it seemed logical not to use the pictures of urban environments. Together with the students I decided on using landscape pictures that were at odds with the most preferred landscape. So that would be: chaotic natural scenes with a restricted view and no deflected vistas or water. As I discussed my experiment setup with Sarah she strongly recommended I’d use a control set of stimuli. That way I could (hopefully) confirm the findings from other experiments and I’d have a contrast set to compare the natural scenes to and hopefully see significant differences between the contrast set and the different landscapes. As the installation will be placed in health care environments I decided to make a set of neutral hospital interiors as a contrast set.


The final installation will be an animation so I wanted to use sets of landscapes to mimic a little the animation effect. We decided on sets of 6 images. Then we had to figure out what time the images would need to be shown to have a measurable effect. Not very much could be found in literature about this so the students did some tests, showing the images for different time periods. The result on the heart-rate was very diverse. So I consulted Malcolm and asked him what to make of this. He said the sample was too small to conclude anything. His suggestion was to show people two sets with the images displaying at different lengths and then to ask people what they preferred. He had already pointed out earlier that it does take some time for stimuli to take effect. Unfortunately the students only tested 10 and 25 seconds to compare. From that they concluded that 25 seconds was a bit too long but that people preferred the longer exposure. So we settled for 20 seconds per image. And each set would last two minutes.

Of course a baseline measurement was needed for the heart-rate as well as the self reported data (view below). For the experiment to have any scientific value Malcolm said I needed at least five minutes of baseline measurement. Not to complicate things further Hein advised to not make use of any specific stimulus but just use an empty screen. It would be quite a long time to sit there and do and see nothing, but it would be for the good cause!

As I reported earlier the research on the effects of natural sounds has been a lot more sparse. But as with visual landscapes water was perceived as more pleasant compared to for example mechanical sounds. And aesthetically pleasing an non-threating bird sounds seem to indicate a positive effect on attention restoration and stress reduction. So we used different combinations of water and bird sounds. The hospital interior set was accompanied by sounds from a hospital waiting room.

In this review of health effects of viewing landscapes there’s an extensive list of research and physiological parameters measured. For Virtual View I’m interested in heart-rate and heart-coherence. Further more I would like to know how a certain landscape makes people feel. I want the installation to have a relaxing effect and to positively influence a sense of well-being. For measuring the physiological side I of course use the Heartlive sensor. I measures beats per minute and calculates heart-cohere. The EventIDE software logs the heart data every second and calculates means for every picture.

Not only do I not own a device to measure for example skin conductivity (GSR) I’m also curious about how people feel when watching the sets. So I needed some record of perceived relaxation state and affect. It was not easy to find a (short) questionnaire which measures that. Malcolm pointed me to the Smith Relaxation States Inventory 3 (SRSI3). It is a very interesting and validated inventory but alas consists of 38 items. It doesn’t make sense to ask people 38 questions after two minutes of pictures. The questionnaire may not be modified without consent so I asked Sarah what to do. She suggested to simplify things and just ask people how relaxed they are on a 10 point scale.

She said 10 points are better then five because it is easier to see the middle and it is more fine grained. It gives people the opportunity to pinpoint how they feel. We settled on three questions: I feel at ease, I feel relaxed, I feel joyful and happy. If my installation can make that happen I’m satisfied no matter what the heart-cohere or heart-rate is. All questions are integrated in EventIDE. Carlos, one of the students, made a nice colour feedback on the scale.

The students take notes of remarks the participants make on their experience of the trail. This may also yield interesting results in relation to the experiment data.

Virtual View: building an experiment

I was very lucky to meet Ilia from Okazolab. When I told him about Virtual View and the research I was planning to do he offered me a licence to work with EventIDE. This is a state of the art stimulus creation software package for building (psychological) experiments with all kinds of stimuli. Ilia has build this software which was, at the time I met him, still under development. Besides letting me use the software he offered to build an extension to work with the Heartlive sensor. He’s been very supportive in helping me to build my first experiment in EventIDE.

It is a very powerful program so it does take a while to get the hang of it. The main concept is the use of Events (a bit similar to slides in a PowerPoint presentation) and the flow between these events. Each event can have a duration assigned to it. On the events you can place all kinds of Elements ranging from bitmap renderers to audio players and port listeners. Different parts of the Event time line can have snippets of code attached to it. The program is written in .NET and you can do your coding in .NET and also use XAML to create a gui screen and bind items like buttons or sliders to variables which you can store.

You can quickly import all the stimuli you want to use and manage or update them in the library. From the library you drag an item onto a renderer Element so it can be displayed and gets a unique id. We’ll use this id to check to responses to the individual images.

The Events don’t have to follow a linear path. You can make the flow of the experiment conditional. So for my design I made a sub layer on the main Event time line which holds the sets of images and sounds. The images in each set are randomised by a script and so are the sets themselves as we want to rule out the effect of order of the presentation. So in the picture you can see the loop containing a neutral stimulus, 6 landscape pictures with a sound and a questionnaire. This runs 5 times and goes to the Event announcing the end of the experiment. During the baseline measurement and the sets the heart rate of the participant is measured. And the answers to the questions belonging to each set are logged.

Data acquisition and storage is managed with the Reporter element. You can log all the variables used in the program and determine the layout of the output. After the trial you can export the data directly to Excel or a text or csv file. Apart from just logging the incoming heart rate values we calculated mean from them inside EventIDE for each image and for the baseline measurement. This way we can see at a glance what is happening with the responses to the different images.

For me it was kind of hard to find my way in the program. What snippet goes where, how do I navigate to the different parts of the experiment? But the more I’ve worked with the program the more impressed I’ve become. It feels really reliable and with the runs history you are sure none of your precious data is lost.

Virtual View: Literature research

To get a better idea of which type of landscapes and sound have the biggest effect on (experienced) relaxation explorative research is necessary. At the end of January I started the research trajectory for the project. This is a collaboration with students from the minor “Active ageing” from the Avans Hogeschool. The three students are: Simone van den Broek, Carlos Ramos Rodriguez and Denise Hereijgers. There is support from two teachers from Avans: Marleen Mares and Lowie van Doninck.

Both the students and I started on a literature study. The main questions being:

Which visual elements in a landscape and what landscape properties have the most effect on relaxation and heart rate variability?

Which nature sounds and sound properties have the most effect on relaxation and heart rate variability?

Which emotional, physical and cognitive aspects influence stress and relaxation in relation to nature and landscapes?

To get the students started I made a list of tags to search on: Environmental psychology, Stress, Arousal, Heartrate Variability (HRV), Heartrate coherence, Relaxation, Landscape Aesthetic Quality, View, Landscape preference, Environmental aesthetics, Restorative environments, Attention restoration theory (ART), Stress recovery, Sounds, Birdsong, Stress Recovery Theory (SRT), Skin Conductancy Level, Effortless attention, Soft fascination, Aesthetic, levels of complexity, pattern, depth, surface texture, mystery within an environment, acoustic properties of animal sounds: smoothness, intensity, pitch, biophilia.

There are a couple of authorities in this field: Roger Ulrich and Kaplan & Kaplan. They have done extensive research on visual landscape preferences and restorative properties of nature. While the students search was broader my main focus was on environmental psychology. There has been quite a lot of research on the effect of viewing landscapes and natural scenes versus urban scenes. A lot less research has gone into the effect of nature sounds on health and relaxation.

From Human responses to vegetation and landscapes Roger S. Ulrich (1985)

An example of a preferred landscape from the article Human responses to vegetation and landscapes Roger S. Ulrich (1985). This is the kind of landscapes we’ll use in our experiment.

For me this was my first experience of reading scientific articles on one theme. Some of the findings conflict and I had a hard time combining the theories and findings into a coherent story. (A more official article will follow later.) One of the students suggested looking at the virtual aspect of the piece and how that influences the experience. I hadn’t thought of that so that was valuable input to explore. Most difficult is to draw the line at one point and start thinking about the actual experiment.

For our experiment we’ll be using sets of static images accompanied by existing nature sounds. Three sets of landscapes are based on preferred and fascinating aspects of landscapes as researched by Ulrich and Kaplan & Kaplan. One set of landscapes consists preferred landscape scenes but in the form of abstract paintings. A contrast set consists of neutral hospital interiors. For the sounds we have chosen different combinations of water and bird song sound. As a contrast we’ll be using sounds from a hospital ward. More about the actual experiment design and consideration in the next blog.