• No results found

Creating safe auditory environments for people with intellectual disabilities


Academic year: 2021

Share "Creating safe auditory environments for people with intellectual disabilities"


Bezig met laden.... (Bekijk nu de volledige tekst)

Hele tekst


Creating safe auditory environments for people with intellectual


Wolter Peterson

July 2014

Master Thesis Artificial Intelligence Dept. Artificial Intelligence

University of Groningen, The Netherlands


dr. Tjeerd C. Andringa (Artificial Intelligence, University of Groningen) Secondary Assessor:

dr. Sietse M. van Netten (Artificial Intelligence, University of Groningen)



Current theories in soundscape research state that in order to be in a positive mood we need sonic environments that enable this. Recent work on the understanding of sonic environments of people with intellectual disabilities (ID) and their reaction to these environments showed there is much to be gained for this group. This thesis attempts to determine whether current theories on soundscapes also hold for people with intellectual disabilities and in what way this could be used to improve their living environments.

21 persons with intellectual disabilities were brought into several different and artificially created sonic environments. By varying how perceptually demanding the environments were and how strongly they featured natural source characteristics, an attempt was made to determine whether or not the responses of this particular group are in line with current theories based on the general population. During their exposure to these environments the mood of the participants was rated by their caretakers. Afterwards a questionnaire survey and a brainstorm session were held to gain additional information on how the caretakers thought the sound influenced the clients.

Results show that proper (sonic) environments can allow people with ID to reach more pos- itive mental states. What constitutes these environments, to what extent sound is a factor in this - compared to elements such as the presence of caretakers - and what kind of sonic environ- ments work best for this group was not clearly established and remains a subject for further research.

Keywords: soundscapes, sonic environments, core affect, intellectual disabilities, quality of life



I want to take a moment to thank a couple of people without whom this project would not have been possible.

First I want to thank Renger Koning1 who, out of enthusiasm and free of charge, created the sound materials used in the experiment. Without him and his expertise the sounds used in this study would not have had the quality they were now.

Secondly I want to thank the caretakers at the activities location where I had the privilege to spend the nine weeks of my experiment. Not only were they enthusiastic, patient, helpful and friendly even though I asked a lot of their time, they also provided me with the unique opportunity to interact with the clients during breaks and lunchtime.

Finally I want to thank my supervisors Tjeerd Andringa and Kirsten van den Bosch for their support and guidance during this project, and my secondary assessor Sietse van Netten for his feedback and helping me not lose sight of the artificial intelligence methods and values during this more special needs care oriented project.

1Renger Koning is a composer for audio visual productions, such as film and commercials. His work can be found at http://www.soundbase.nl/



1 Introduction 1

1.1 Research Question . . . 1

1.2 Thesis Outline . . . 2

2 Theoretical Background 3 2.1 Sound and its Relation to Mood and Health . . . 3

2.1.1 Core Affect . . . 3

2.1.2 Appraisal and Sonic Environments . . . 4

2.2 Persons with Intellectual Disabilities . . . 5

3 Methods 8 3.1 Participants . . . 8

3.2 Sounds . . . 8

3.3 Setup and Procedure . . . 12

3.4 Questionnaire and Brainstorm . . . 13

4 Results 14 4.1 Core Affect . . . 14

4.2 Written Remarks . . . 19

4.3 Questionnaire . . . 21

5 Discussion 23 5.1 General Discussion . . . 23

5.2 Remarks on our Methods . . . 25

5.3 Futher Research . . . 26

5.4 Conclusion . . . 27

Bibliography 29

A Assessment Form 30

B Questionnaire 33


Chapter 1


Media from time to time reports on conflicts arising when people living near an airport or major road complain about the level of noise and how this influences their lives in a negative way. Sound is everywhere in our daily lives. Our environment contains a myriad of objects and living organisms that all produce sound. Some sounds, as in the example above, seem to influence us in a negative way. Other sounds, such as for example the songs of birds in the park we visit to clear our head, seem to be beneficial.

Recent research into soundscapes, core affect, and appraisal theorizes that sound influences on a basic (or primitive) level. Sub-cortical processes use sound to determine where we are and in what state (safe or unsafe) our current environment is. The theory proposes that, when the sound in the environment indicates a safe and normal state, we should feel more relaxed and free to follow our own actions and lines of thought. In the average person, cortical processes use visual processing and culturally determined cues to augment this basic, sound driven, assessment of the environment [2, 23] . This allows us to function normally even in less desirable sonic environments.

To study the full effects of sound on our moods researchers started working with persons with Profound Intellectual (and Multiple) Disabilities. These persons have an intellectual developmental age much lower than their actual age and this leads to them not being able to process their environment as elaborately and biased as healthy people.

Researchers noticed that persons with an intellectual disability do respond, sometimes even strongly, to sounds in their environment. However, it might be the case that they are not living in a positive, i.e. pleasant, sonic environment. Providing such an environment could improve the quality of lives and findings from soundscape research seem to provide us with a solid framework to design improved living environments. However, soundscape and appraisal theories have mostly been developed for healthy individuals and might not hold, or at least be slightly different, for this particular group of people.

1.1 Research Question

This project aims to gain insights into whether persons with intellectual disabilities respond similarly to sounds and sonic environments as most healthy people, and whether providing them with an improved sonic environment allows them, as the theory predicts, to reach a more desirable state of being that is characterized by decreased anxiety and stress and more prolonged periods with a positive mood. This project should provide insights into which sounds provide these persons with the opportunity of being in a pleasant mood and it should shed light on which features in sound are most likely to be the cause of certain moods.

| 1


1.2. Thesis Outline

The questions we want to answer with this project are:

1. Can we create a sonic environment that helps persons with an intellectual disability to reach a pleasant state of being (in terms of core affect)?

2. Which sounds enable this and what are the characteristics of these sounds?

3. How does this compare to the original theory on appraisal and influence of sounds?

1.2 Thesis Outline

The rest of the chapters aim to answer the questions posed above. Chapter 2 outlines the theoretical background, explaining the important concepts and giving an account of the group of people that are the focus of this study. Chapter 3 details the setup and execution of the experiments. Chapter 4 summarizes the results from the measurements. In Chapter 5 conclusions are drawn on the effect the approach has on the persons with an intellectual disability and inferences are made about how this could affect the care these people (should) receive. In chapter 5 implications of our findings for the theory as it was outlined in chapter 2 are also discussed.

| 2


Chapter 2

Theoretical Background

This chapter outlines the core concepts used in the project. Because his project follows closely on earlier work and as such follows the theory used in that work, section 2.1 is strongly based on work by Andringa et al.[1]. Section 2.2 discusses the disabilities of our participants.

2.1 Sound and its Relation to Mood and Health

Although we often think we use audition, our capability to hear and listen, predominantly to understand speech and listen to music, this is only a recent (in evolutionary terms) use [15].

Following the theory outlined in [1], the evolutionary use of audition has been to warn us when we were in danger or should be more alert. It has on this basis been argued that the most important function of hearing is (still) determining safety. Determining safety is argued to be a sub-cortical process, occurring unconsciously and before any other processing takes place. When the sub-cortical processes deem a situation to be safe, higher cognitive functions are free to focus on what they see fit. In an unsafe situation cortical processes are forced to actively attend the situation and search for sources of danger or safety. This active form of processing is associated with higher arousal and when maintained too long it can have a negative impact on health [1].

The sub-cortical processes are thought to determine a sense of place [23]. To gain a sense of place, answers to two questions are needed [19]: (1) Where am I? and (2) What is happening? When either of these questions is answered negatively, or cannot be answered at all, safety cannot be determined and cortical processes are forced to actively attend the environment. The sounds that cause the failure of positively determining safety are seen as annoying. Two central concepts, namely core affect and appraisal, are strongly influenced by the ability to answer these two questions. These two concepts are in turn closely coupled to the health-impeding effects of sound. In this process the ”what” question seems to have a bigger impact compared to the ”where” question.

2.1.1 Core Affect

Core affect [21] is related to moods. Core affect (figure 2.1a) is the combination of pleasantness (valence) and activeness (arousal) we feel at a certain moment. Although it seems similar to emotions, core affect differs from emotions in that it is continually present to self-report [2] and usually exists without being attributed to a cause or being labelled [21].

In core affect, the plane spanned by the two dimensions divides the possible states into four quadrants. In the top-right quadrant a person is active and self guided. When a person crosses over into the top-left quadrant the active behaviour remains, but the individual feels as if losing control. This leads to a state of anxiousness. The lower half of the graph is related to less active

| 3


2.1. Sound and its Relation to Mood and Health

moods. In the lower left quadrant the individual does not feel in control and minimal self-initiated action is taken. The lower-right corner illustrates a restorative mood. The individual is also not very active, but does feel safe and in control and can, but does not need to, perform self initiated actions. Ideally people should be in the right half of the circle as much as possible.

Figure 2.1: Image showing the dimensions and related terms for core affect (a) and appraisal of the environment (b). Image adapted from [1]

2.1.2 Appraisal and Sonic Environments

Appraisal [4] (figure 2.1b) is similar to core affect, but refers to the state of the outside world, as perceived by the individual, instead of the internal state of the individual. Appraisal is described in similar terms as core affect, with the dimensions being pleasantness and eventfulness.

Recent work by Kuppens et al. [17] reported a bidirectional influence between appraisal and core affect. In other words, if we appraise an environment positively it will have a positive effect on our mood and a positive mood will result in a more positive appraisal of our environment. This however also holds for negative core affect and appraisal. This interplay therefore has the potential for a self-strengthening cycle in either a positive or negative direction.

Appraising an environment involves determining the possible interactions with that environment [3]. It is argued that appraisal is strongly related to motivation, coping capacity and expectations of the future [17, 2]. Kuppens et al. [17] list motivational relevance (is it important?); motivational congruence (is it advantageous?); agency (is it caused by myself or by others?); coping potential (can I cope with the situation and my emotions?); and future expectancy (is the expected outcome desired?) as factors that are relevant when appraising an environment. These questions lead to an evaluation of the environment in terms of the action possibilities that are available and should lead to selecting the possibility with the most preferred outcome.

Possibility (or action) selection in a certain environment, as indicated by the factors listed by Kuppens et al., can be summarized in two questions: (1) What actions can be taken in this environment? and (2) How to decide what the best action would be? These two questions refer to affordances and complexity respectively. Affordances are the possible actions in an environment as perceived by an agent [6]. Complexity refers to how difficult it is for an agent to decide which course of action to take in an environment [3]. Figure 2.2 shows these two concepts as diagonal axis within the figure of core affect.

Next to signalling action potential in an environment, complexity and affordances are also related to safety. In a negatively complex environment, an environment that is either too complex

| 4


2.2. Persons with Intellectual Disabilities

or too simple, no (or not enough) indicators of safety are present, or they are all lost in the large number of stimuli [2]. This in turn leads to the individual not being able to answer whether the current environment is in its safe state and thus leads to higher arousal (following the reasoning from [1]).

Figure 2.2: Four types of sonic environments based on complexity and affordances connected to the concept of core affect.

Image adapted from [2]

An analysis by Andringa et al. [2] suggest four different types of sonic environments based on a complexity and an affordances dimension. The resulting division into four types of environments closely fits both of the two-dimensional descriptions of core affect and appraisal. These four types of environments, and their characteristics, are illustrated in figure 2.2 by the four descriptions outside the circle. Environments with a low complexity are highly redundant and safe, and allow for a relaxed state. High complexity environments force an agent to be more alert because safety cannot be estimated. An environment with many affordances allows for an active (exploratory) appraisal of the environment while an environment low on affordances is appraised as being monotonous and boring.

Figure 2.3 shows a dictionary description of the words that are often used to describe (appraise) certain sonic environments. This illustrates the link between appraisal and the four types of sonic environments. Linking the descriptions to appraisal in this way clarifies the placement of the descriptions in figure 2.2.

2.2 Persons with Intellectual Disabilities

As described above, sound greatly influences the way we feel and interact with our environment.

However, higher level cognitive functions likely allow us to modify the influence sub-cortical processes have on our behaviour [1]. Using different cultural cues we are, even in otherwise unpleasant sonic environments, able to feel at ease and to function normally. For people who are less able to augment the primitive influence sound has on us, such as persons with intellectual disabilities [23], an inherently pleasant sonic environment seems to be even more important.

This project is aimed towards people with severe to profound intellectual disabilities. This entails that the people of interest for our study have a developmental age not surpassing approximately 3

| 5


2.2. Persons with Intellectual Disabilities

Figure 2.3: Four sonic environments based on complexity and affordances in relation to words commonly used in appraising sonic environments. The image illustrates the link between sonic environments and appraisal. Image adapted from [2]

years. Stemming from a disability, their brain has not developed the higher cognitive functions we rely on in our every day lives. The American Psychological Association classifies intellectual disability (ID) as being present when the IQ is at least two standard deviations below average.

This means that a person with an IQ of 70 or below is classified as having an intellectual disability.

Intellectual disability is subdivided into mild ID (IQ between 55 and 70), moderate ID (IQ between 35 and 55), severe ID (IQ between 20 and 35) and profound ID (IQ below 20) [20]. In addition to this, persons with severe or profound ID will likely show disabilities in learning adaptive behaviours and are unable to do simple every day activities without considerable support [11]. Next to their developmental disability, many of them will have physical or sensory, predominantly visual [24], impairments [14]. Because of this persons with ID will rely more strongly on audition [13].

Additionally they often have strongly impaired or absent linguistic capabilities [9]. For persons with mild or moderate ID language skills are usually better developed. These groups are also sometimes capable of having social relationships and holding a daytime job - albeit a structured and well supervised one - and although rates are lower as in the general population, persons with mild ID can lead fairly normal lives independently. Persons with more severe forms of ID mostly live and spend their time with organisations specialised in special needs care.

In addition the having an intellectual disability, the persons in our target group exhibit one or more forms of challenging behaviour. Challenging behaviour occurs in 5 to 15% of individuals with ID, with prevalence being higher for individuals with more severe intellectual disabilities [12] and for those who are also diagnosed with an autism spectrum disorder [8]. Challenging behaviour has been defined as

...culturally abnormal behaviour(s) of such an intensity, frequency or duration that the physical safety of the person or others is likely to be placed in serious jeopardy, or

| 6


2.2. Persons with Intellectual Disabilities

behaviour which is likely to seriously limit use of, or result in the person being denied access to, ordinary community facilities...[10]

In practice this includes, but is not limited to, behaviours such as destructive behaviour (towards surroundings), physical and verbal aggression, self-injury, screaming, and sexually crossing beha- viour. Prevalence studies often subdivide challenging behaviour in forms that are more or less demanding [16]

Challenging behaviours further complicate the already troubled lives of persons with ID. It interferes with social interactions and requires more, and more specialised, care. In recent decades thinking has shifted from seeing challenging behaviour as a cause to seeing challenging behaviour as the result of operant conditioning where the problematic behaviour has in the past somehow often resulted in a favourable outcome for the person exhibiting this behaviour [8].

| 7


Chapter 3


This study focusses on whether sonic environments influence people with intellectual disabilities in a similar way as found on the general population. Persons with ID can not be tested in similar ways as regular test subjects. We decided that regular forms of measurements (both qualitative and quantitative) are too invasive. The influence of the environment on persons with ID was determined through observations by an other person. In our case the caretakers.

3.1 Participants

Participants were 21 clients from an activities facility for people with an intellectual disability and challenging behaviour. The activities centre is part of an organization for special needs care from the northern Netherlands. Legal representatives of all 35 clients attending this activities centre were contacted. Informed consent was obtained for 25 of the clients. Of these 25 clients, four were excluded from the experiment because they refused to enter the room with the experimental setup upon being brought there for their first session. Several attempts were made with these participants prior to excluding them. Refusal was made clear by stating strongly they did not want to enter, for the clients with developed speech, or by showing behaviour indicative of refusal such as pulling the caretaker away from the room, screaming, aggression or self-injury.

The remaining 21 participants (age 17-55, Mean: 40, SD: 13) all completed the experiment. Of the participants 13 were male (62%) and 8 (38%) were female. From our group of participants one person is classified as having mild intellectual disability, two are classified as having a moderate intellectual disability, 15 are classified as having a severe intellectual disability and the remaining two are classified as having a profound intellectual disability. All but one off the clients has an autism spectrum disorder and seven are diagnosed with epilepsy. The challenging behavior of the clients includes destructive behaviour (N=8), stereotypical movements (N=6), self-injury (N=10), aggression (N=10), (social) withdrawal (N=7), screaming (N=4), and sexually crossing behaviour (N=1). Multiple behaviours are usually present in a client, resulting inP N > 21 in this list.

3.2 Sounds

Five different sonic environments were created during this study. Three different sounds recreating real world environments were supplemented with a silent condition (simply not playing a sound) and an ambient music piece. The sounds were chosen to be either calming or lively, following the reasoning from Andringa et al. [2]. In the terms used in chapter 2 this entails the environments are of low complexity but contain enough indicators of safety. We choose to include a forest environment, a beach environment and an urban environment. All three soundscapes and the music piece were designed and created by a professional composer.

| 8


3.2. Sounds

Image 3.1 shows cochleograms of 10 minute excerpts from the four different sounds. Although physical properties are not the most important factors for appraisal [2], they do provide a useful tool for evaluating what is happening in the sounds.

The forest sound (figure 3.1a) mainly consists of birds and the wind in the trees. The beach sound (figure 3.1b) predominantly contains the sound of waves crashing on a beach. Both sounds were kept deliberately sparse to create calm environments. The cochleograms show that both sounds contain a lot of broad band noise (energy in all bands). The main difference is that the forest sound has energy peaks in the high frequency regions, due to the high frequency of bird songs, while the beach sound is high in energy over a large part of the frequency spectrum.

The urban soundscape (figure 3.1c) contains sounds from different parts of the city of Groningen.

This sound varies more in its content and the amount of activity present in the sound, leading to a more lively environment. Elements in this sound range from almost silent with just a bit of traffic - such as can be seen around the 400 seconds mark - to a busy market square - around the 250

second mark - and children playing outside their school.

The forest, beach and urban sounds were created using different recordings from real world environments. The ambient music piece (figure 3.1d) is entirely computer generated. It is a very calm and slow tonal composition, utilizing mainly single notes that trail away using reverberations.

The ambient environment was designed to be tranquil and calming just like the two nature sounds, but unlike the forest and beach sounds it has no natural source characteristics. As can be seen the energy of the music sound is located at the frequencies of the tones and very little noise is present.

| 9


3.2. Sounds

(a) Cochleogram of the Forest sound

(b) Cochleogram of the Beach sound | 10


3.2. Sounds

(c) Cochleogram of the Urban sound

(d) Cochleogram of the Music sound

Figure 3.1: Cochleograms of the four different sounds used to create the sonic environments in the experiment.

| 11


3.3. Setup and Procedure

During the sessions of the experiment the sounds were played at similar energy levels to reduce effects from loudness. After comments from caretakers some sounds were played slightly louder to resemble reality more realistically, while still feeling comfortable in the enclosed and parse environment of our experimental setup. Table 3.1 summarizes the loudness at which the different sonic environments were created during the sessions with participants. All loudness levels during the experiment were well within bounds for regulations for sound annoyance. The sounds were perhaps even played slightly less loud than they would occur in the real world, possibly stemming from the sounds standing out more in the enclosed space.

Table 3.1: Table showing the loudness measurements for the various soundscapes. Loudness measurements were done using an android smartphone running a popular sound meter app.

minimum (dB) maximum (dB) average (dB)

Forest 25 47 36

Beach 26 51 41

Urban 22 58 41

Music 19 50 35

Silence1 13 30 24

3.3 Setup and Procedure

For the experiment a room was equipped to allow the creation of sonic environments using a 6 speaker layout. The activities centre gave permission to use a never used time-out (or isolation) room. The room was situated slightly apart from the rest of the building and could be reached by a small (1.5m long) corridor. This semi loose placement entailed partial insulation from sound from the rest of the building. Bookshelves filled with insulating material were placed against the walls of the room, and the speakers and other electronics were placed inside the shelves. The material in the shelves gave the room, which initially was empty and has plastic walls, better acoustic properties. Additionally two chairs and a table were placed to fill the room, create a more welcoming environment, and to allow the client and caretaker to sit during the experiment.

Complete sound insulation was not possible with the room and resources available. When sounds from outside the room, from for example a lawnmower, were distinctly audible over the sonic environment in the room, sessions were stopped and rescheduled.

A typical session of the experiment started with the client and caretaker being retrieved from their group in the activities centre. The client would enter the room together with the caretaker while the experimenter stayed outside and observed using a live camera feed.

Upon entering, one of the five sonic environments was being created inside the experiment room. Sessions lasted until the client indicated wanting to leave, with a maximum of 20 minutes.

During this time clients were free to move around the room and behave as they wanted. Caretakers were instructed to observe the behaviour of the clients during the session and report on their mood at the start and at the end of the session. They were also asked to write down anything in the behaviour of the client that stood out to them. Each participant underwent ten sessions of the experiment, twice for each of the five condition, over the course of nine weeks. The order in which the participants received the conditions was randomized for each participant.

1Total insulation was not possible. Because of this some sound from outside was audible in the room where the experiments took place.

| 12


3.4. Questionnaire and Brainstorm

Reports on the mood of the participants were obtained using the assessment form shown in appendix A. Caretakers were asked to indicate which of the nine sections of the graph best described the mood of the client. The main part of the form is a representation of the core affect graph including the complexity and affordances axis as explained in chapter 2. An additional section, termed ”neutral” was added to account for non-outspoken moods in clients.

The assessment form is based on core affect and the assessment auditieve omgeving created by Van den Bosch in an earlier project with persons with ID [22]. This simplified method, and not the full assessment auditieve omgeving or a more elaborate rating scale such as for example the Philadelphia Geriatric Center Affect Rating Scale [18] (also known as OERS), was chosen because it is easy and quick to fill in. This entailed caretakers were not unnecessarily burdened by reporting the moods of the clients which ensured they could stay focussed on their care duties.

When caretakers, against instructions, indicated more than one section of the graph, the experimenter would explicitly ask which section fit best. This ensured one answer was selected each time. Additional information that was recorded at each session was the time duration of the session, which condition was used and which caretaker was with the client.

3.4 Questionnaire and Brainstorm

The experiment, as described in the sections above, involved several elements that were new and unknown to the clients. These new elements include the sonic environment, but also the room with the experimental setup and being there with the caretaker. To provide additional context for the results of the experiment and to discover what might have been the biggest influences on the results a questionnaire was held among the caretakers who had been involved in the experimental sessions with one or more of the participants. The questionnaire, in Dutch and attached as appendix B, was held using an online form. The questionnaire determined to what extent the sound influenced the participants, whether or not this was the main influence during the sessions, and whether there are sounds that are generally more or less preferable. The last few questions were added to acquire a feeling on whether caretakers thought interventions based on sound might have possible positive benefits when applied as part of the day-to-day setting and routine of the groups at the activities centre.

The results of the sessions and the outcome of the questionnaire served as the basis for a brainstorm session with the involved caretakers. The goal of this session was similar to that of the questionnaire: to gain more insight into what caused the reactions of the clients. The session started with a brief presentation on the results obtained from the core affect ratings and the duration scores, which are addressed in section 4.1. Next, caretakers were asked what they thought of the sessions, what they thought had the most influence on the mood of the clients, and whether they thought sound was important for clients to feel well. During the brainstorm stories and anecdotes formed the bulk of the answers. This provided qualitative additions to the questions posed in the questionnaire. Sound recordings and hand written notes were taken during the session to be analysed later on.

| 13


Chapter 4


This chapter reports the results of the study. First the quantitative data obtained during the sessions of the experiment will be analysed, using both descriptive and analytical methods. After that the comments written down by caretakers during the sessions will be analysed and finally trends in the questionnaire will be discussed.

4.1 Core Affect

The goal of the experiment was to establish whether or not the sonic environments that were created had a (positive) influence on the mood of the clients. Insights in this were obtained by looking at (1) the core affect measurements, and in particular the change during the sessions; and (2) Whether or not clients chose to spend more time in the room under certain conditions.

21 participants finished the experiments. Two participants were unable to sit still and not be busy with a task for more than a minute. During the sessions several approaches, including handing them a task, were tried to keep them busy in the room. This led to a difference in methodology between them and the other 19 participants. Because of this their data was excluded from the analysis. This resulted in 190 datapoints, ten for each of the remaining 19 participants, being used.

Checks performed after the analysis revealed only very small differences in the results would occur if the two excluded participants would have been included.

Figure 4.1 shows four graphs on the core affect. For this graph all 190 measurements were used and no distinction was made between the different conditions. The two graphs at the top of the figure, a ”rose-plot” and a ”compass-plot”, were created by turning each of the nine categories into x and y coordinates that would lie in the middle of their respective categories. The length of the axis is taken to be 1. In other words, the octant indicated by the keyword ”active” on our assessment form is coded as [0.272 0.656] and the octant indicated by the keyword ”relaxed” is coded as [0.276 −0.656]. The neutral part is coded as [0, 0]. The bottom two graphs depict the prevalence of being in a certain affect state. Here the left graph represents core affect at the start of the sessions and the right graph shows core affect at the end of the session. For these two graphs the core affect measurements of the nine categories were binned into five categories. The eight outer sections were combined into their respective quadrant from core affect and the fifth group represents the neutral measurements (See table 4.1 for an illustration). The fifth, neutral, category was not included in the graphs here, but was taken into account in further analysis.

| 14


4.1. Core Affect

Table 4.1: Table illustrating how the nine categories from our assessment form were binned into the five categories used in the analysis. The five bins are represented by keywords from the core affect graph. The neutral category, which is not present in core affect, is retained as a separate category.

Actief Ge¨ınteresseerd Genietend Ontspannen Duf Verveeld Angstig Ge¨ırriteerd Neutraal

Interested Relaxed Bored Distressed Neutral

The top two graphs show the direction of the distribution is mainly towards the pleasant, right, side of the figure, with the direction towards the bottom right being dominant. This trend in the direction distribution is also visible in the two density plots at the bottom of the figure. At the start of the sessions the clients seem to be mostly in an active/interested state with an equal amount being either relaxed of distressed. During the session most clients seem to move towards a non-activated state, with the movement towards the relaxed state being most prevalent. A few clients stayed, or became, interested or distressed. Figure 4.2 shows the contingency table for the core affect before and after the session. An exact McNemar’s test determined this movement, or difference, in the core affect represents a significant change, p < 0.01. The number of clients in a relaxed state increased from 26% to 50% of the total amount of measurements. The number of clients in the categories ”interested”, ”distressed” and ”neutral” decreased from 39% to 19%, 24%

to 13% and 10% to 5’% respectively. The number of clients in a bored state increased from 1% to 13%.

Figure 4.1: Figure showing direction distributions of the change between core affect at the start and at the end of the sessions, and density plots of the core affect at the start and the end of the sessions. No distinction was made between the different conditions or participants. Both the direction distributions and the density plots show a trend towards the relaxed states.

| 15


4.1. Core Affect

Table 4.2: The table shows the contingency table for core affect at the start of the sessions and core affect at the end of the sessions. The numbers show there is a shift towards more clients reported as being relaxed or bored, with numbers decreasing for the other categories. The numbers in the table are count data

CA after session

Interested Relaxed Bored Distressed Neutral Total

CA before session Interested 20 38 12 2 2 74

Relaxed 4 29 6 10 1 50

Bored 0 1 0 1 0 2

Distressed 7 19 5 11 3 45

Neutral 5 8 2 0 4 19

Total 36 95 25 24 10 190

Figures 4.2a through 4.2e show the same graphs as described above, but split for each condition.

From these graphs it can be gathered that, although small differences are present in the exact numbers, the same trend is visible for each condition: clients predominantly move towards a relaxed state. Fishers exact tests showed there is no significant difference between core affect at the start the sessions in different conditions (p = 0.198), nor is there a significant difference between core affect at the end of the sessions in different conditions (p = 0.824). Due to the hight number of very low (0) counts in some of the categories, analytical statistics were not possible for the difference between core affect at the start and core affect at the end within different conditions.

Concerns were raised pointing out that clients might have needed quite some time to adjust to the experiment and the new elements it involved, leading to extra confounds during the first amount of sessions and differences in responses between the first and latter sessions. To test this, comparisons were made on core affect between the first time clients received a certain condition (figures 4.3a and 4.3b), and between the first four and last five weeks of the experiment (figures 4.3c and 4.3d). Using Fisher’s Exact Test no significant difference was found for core affect at the start of the sessions for the session based split (p = 0.358) or the week based split (p = 0.204).

Similarly, no significant difference was found for core affect at the end of the session for the session based split (p = 0.622) or the week based split (p = 0.451) either.

Looking at the time clients spend in the room during each session results in similar findings as described above. There is no significant difference in session length between the conditions (F = 0.531; df = 4; p = 0.713). Session length and core affect do seem to correlate. Duration scores (figure 4.4), calculated per 30 seconds, were higher for clients who were reported to have a positive core affect after the session (F = 11.592; df = 4; p < 0.01). Scheffes test revealed the differences are between interested and distressed (p < 0.01), relaxed and distressed (p < 0.01) and bored and distressed (p < 0.01).

Core affect before the session does not correlate significantly with the session duration (F = 0.902; df = 4; p = 0.464), nor is there a significant interaction effect between core affect before and after the session (F = 0.992; df = 12; p = 0.458).

| 16


4.1. Core Affect

(a) (b)

(c) (d)


Figure 4.2: Direction distributions on the change in core affect and density plots of core affect before and after the sessions for each of the different conditions. A similar trend - going from active to non-active, mostly relaxed, states - seems to be present for all conditions.

| 17


4.1. Core Affect

(a) (b)

(c) (d)

Figure 4.3: graphs showing the number of responses on core affect categories split on the first or second time clients received a condition (top two graphs) and on the first four against last five weeks of the experiment (bottom two graphs). The two graphs on the left show the core affect as reported at the start of the session and the two graphs on the right show the core affect at the end of the sessions.

| 18


4.2. Written Remarks

Figure 4.4: Boxplot showing the duration scores against the core affect scores reported for clients after the sessions. Duration scores were calculated in 30 second intervals. Clients seem to stay longer when they were reported to have been in a relaxed or interested state at the end of, and probably during, the session.

4.2 Written Remarks

Part of the assessment form were three fields where caretakers could write down any comments they had about the behaviour or mood of the client. These three fields for remarks signified the start of the session, Opmerkingen bij gedrag en stemming bij binnenkomst ; the time during the session, Opmerkingen bij gedrag en stemming tijdens de sessie; and the end of the session, Opmerkingen bij gedrag en stemming bij einde activiteit. The first and last remarks field were filled in at the same time as the two core affect ratings were given. Most comments by caretaker were just a few words or a single sentence.

Tables 4.3, 4.4, and 4.5 provide summaries of the remarks at each of these moments. These summaries were determined by looking through the remarks for each field and finding commonalities between the remarks. Where possible remarks were grouped based on one of the keywords from core affect. Other summaries were chosen directly from one of the remarks that explained most clearly. Each final group was chosen to not have less than four occurrences. Initial categories that contained two to four instances were either grouped to create a category of at least four instances, or attributed to one of the larger categories closely matching in theme. The ”Other” category signifies remarks that were so unlike the others there was no combined category to be made.

Caretakers did not fill in remarks in all three fields for each session. Where remarks were written down this was always done for at least two of the fields. The total number of remarks by caretakers was 103 for the ”before” field, 102 for the ”during” field, and 65 for the ”at ending”

field. This is out of the total of 190 sessions of the study that are part of this analysis.

| 19


4.2. Written Remarks

Table 4.3: Start of session remarks. The remarks are grouped based on a keyword that closely matched the remark.

Keyword Frequency Percentage

Distressed 19 18,45%

Relaxed 13 12,62%

Interested 13 12,62%

Having difficulty switching 12 11,65%

Neutral 11 10,68%

Immediately focussed on sound 9 8,74%

Tense 8 7,77%

Talkative 7 6,80%

Wanted to go to the sound experience 6 5,83%

Other 5 4,85%

Total 103 100%

Table 4.4: Remarks placed during the sessions. The remarks are grouped based on a keyword that closely matched the remark.

Keyword Frequency Percentage

Relaxed 32 31,68%

Talkative 20 19,80%

Exploratory or Playful 10 9,90%

Enjoying themselves 8 7,92%

Distracted 7 6,93%

Bored 7 6,93%

Distressed 5 4,95%

Sleepy 5 4,95%

Other 7 6,93%

Total 102 100%

Table 4.5: End of session remarks. The remarks are grouped based on a keyword that closely matched the remark.

Keyword Frequency Percentage

Relaxed 24 36,92%

Wanted to leave - Negative mood 12 18,46%

Wanted to leave - Positive mood 9 13,85%

Distressed 6 9,23%

Bored 5 7,69%

Distracted 4 6,14%

Other 5 7,69%

Total 65 100%

An important remark to place here is that these frequencies are from individual comments.

Which client is concerned and what the other comments during this session were is not taken into account. This could, and does in some situations, mean that more than one of the occurrences belongs to the same client. One client could in theory account for up to ten similar remarks. Many similar remarks about one client could therefore skew the image these numbers portray. In table 4.5 this is the case for five of the remarks from the ”positive mood but wants to leave” category.

| 20


4.3. Questionnaire

Being able to group many remarks under keywords also present in core affect seems to be an indication of the strength of core affect. However, because of this strong similarity these remarks unfortunately do not provide us with much additional information. The categories described more descriptively, such as for example Talkative, Wanted to leave, and Having difficulty switching, do provide additional information.

• Talkative, both in the before and during fields, was indicated for four of the clients. For two of them this seemed to be linked to a bored core affect state. For one of them it was unique a caretaker could have an conversation with him, without him becoming distracted. One of these four clients kept talking because she was very anxious. The fourth client seemed to be enjoying himself and was mainly talking to himself.

• Having difficulty switching is used to describe comments that indicated that a client had difficulty with the transition between the activity they were doing before and suddenly being in the room. ”Activity” here is used to signify anything a client could be doing and ranges from cycling outside to sitting still on a couch. This difficulty with the transition was reported for many different clients and not often for the same client.

• Distracted is used to describe comments detailing behaviour where clients were more focussed on, or intrigued by, elements in the room than they were noticing the sound or the caretaker. These other elements could be, for example, the sheets covering the bookshelves or something (some mud, etc) on the floor.

• Sleepy is used to group comments where clients were described to (almost) fall asleep. This was by caretakers seen as a sign of extreme relaxation and the possibility to completely let go.

• The categories Wanted to leave - Negative mood and Wanted to leave - Positive mood describe remarks that stated a client strongly indicated wanting to leave. Interestingly this happened for clients that were in a positive mood as well as for clients that were in a negative mood. As stated, one client accounts for 5/9 occurrences in the positive mood category. This client was very enthusiastic each time, but just stood up and left after approximately 5 minutes. The negative mood category on the other hand, is split more evenly over clients.

4.3 Questionnaire

Ten of the 36 caretakers involved in this study filled in the questionnaire described in section 3.4 . Ten out of 36 caretakers also attended the brainstorm session that was organized as a conclusion to the experiment. It is likely these groups include almost the same ten caretakers. Respondents were approximately equally spread among the different groups at the activities center. The results of the questionnaire are summarised in table 4.6. Except for two questions, all questions in the questionnaire were answered on an ordinal scale with the options 0%, 25%, 50%, 75% or 100%.

Table 4.6 shows the median and mode of the responses. Individually these two central tendencies would not tell us much, but combined they show us whether there is a strong consensus between respondents (when they are similar) or a large variability in answers (when they differ a lot).

Consensus between respondents is a strong indication that the answers reported hold for most of our participants.

Respondents reported that 50 to 100% of the clients responded to the sound (median = 75%).

For the clients that did not respond to the sound responses in the other questions varied greatly.

| 21


4.3. Questionnaire

Table 4.6: Table containing median and mode scores on ten of the questions from the questionnaire. These are the questions where a distinction was made between the group indicated to respond to the sonic environment in the experimental setup and the group that was reported not to respond to the sounds.

The number of responses in both groups is equal to or less than ten. When a respondent indicated that none of the clients responded to sound, the questions on clients that responded to sound could be skipped. When it was reported all clients responded to the sound the questions on clients that did not respond could be skipped.

No response (N=7) Response (N=10)

Change in Mood Median 75% 75%

Mode 25% 75%

Positive change Median 75% 75%

Mode 75% 100%

Enjoyed the experience Median 50% 75%

Mode 75% 75%

Effect lasting after session Median 25% 25%

Mode 0% 25%

Biggest influence The sound The sound

Some respondents reported all of the clients to experience a change in mood while others reported this was the case for none of them. This also occurred in one instance where respondents reported being from the same group. The same holds for whether or not the mood change was positive.

Interestingly enough respondents report that on average in 50% of the cases the sound present during the session is the biggest influence on the mood for this group. This seems to contradict their earlier statement that this group did not respond to the sound. This could either be a confirmation of the idea that sound influences on an unconscious level, where clients do not outwardly respond to the sound but are influenced by it, or an indication that the questionnaire was not entirely clear to caretakers.

For the group that was reported to respond to the sounds the answers are more consistent.

Almost all respondents indicate that nearly all clients in this group liked going into our experimental setup, with 75% of the clients in this group being reported to experience a change in mood. This change is reported as being positive in 75% of the cases. Almost all clients are reported to react differently to different sounds. The beach sound, closely followed by forest and city, is reported as being the most pleasant. The silent condition is in almost all cases reported as being the least pleasant sonic environment. For both groups of clients, those responding to sound and those that do not, most respondents indicate there is little lasting effect when the clients returned to the group.

The last two questions of the questionnaire concern predictions by the caretakers on whether or not they think sound can have a positive influence when used properly at the normal groups and whether they think it can have a positive influence on the behaviour of the clients. Here all respondents indicate they think a pleasant sonic environment will help improve the atmosphere on the group and seven out of ten indicated they also believe a pleasant sonic environment would decrease the occurrence of challenging behaviour.

| 22


Chapter 5


Following the theory outlined in chapter 2, participants were expected to respond to sounds similarly, or perhaps even more strongly, as normal subjects. That is to say, they were expected to be more, and more quickly, aroused in busy or chaotic sonic environments while still very much enjoying calm environments. Clients were expected to favour calm environments over busy environments and to favour environments with natural source characteristics over man made sounds. In this study the calm and natural environments were represented by our forest and beach condition and the busy environment was created with the city condition. The music sound represents a calm environment without natural source characteristics.

5.1 General Discussion

In chapter 4 it was shown that the participants did indeed often move towards a positive, mostly relaxed, mood. This seems to indicate that it is possible to create an environment that is pleasant for this group of people. What the precise prerequisites of such an environment are unfortunately remains less clear.

Although the results in chapter 4 show an improvement in mood, figure 4.2 illustrates this change holds in all our experimental conditions. There seems to be no preference for calm environments - forest and beach - over more busy environments such as the city. There also seems to be no indication that environments with natural source characteristics - forest and beach - are more preferable than environments without these characteristics, such as the music condition.

Even the silent condition, which was expected to be the least preferable, seems to have provided a pleasant sonic environment. During the experiment this condition meant there was no sound produced during a session. It was theorized this would create an empty and lifeless environment that would be low on affordances. The expectation was that this silent condition would lead to a bored mood, indicated by a more lethargic posture. However, clients seem to have been relaxed and happy during this condition as well.

That the results follow this unexpected pattern could be the result from other factors besides the sound having a strong influence. In the questionnaire sound was indicated as the strongest influence on the mood of the clients. For the group that was reported to respond to the sound this however made up only 40% of the responses. 30% stated the 1-on-1 contact with the caretaker was the most important influence, 20% indicated the room as being the biggest influence, and the remaining 10% reported that it was providing the sessions as an activity had the biggest effect on the mood.

For the clients that did not seem to respond to the sound this distribution is approximately the same. These factors and their influence are looked at in more detail in section 5.2. For now it suffices to say that it seems that the clients are highly sensitive to context.

| 23


5.1. General Discussion

One might expect there to be some form of habituation leading to less influence by some of these factors. This could have been illustrated by a difference between responses during the first part of the experiment and the second part of the experiment. As shown in figure 4.3 and accompanying text, this is not the case.

Figure 4.4 shows the duration of the sessions with respect to the mood clients were in at the end of the session. From this it seems to follow that the clients are able to determine whether or not they find their environment pleasant or not. They are also very well capable to indicate their displeasure and perform behaviour that will likely lead to caretakers acting to bring the clients to a more pleasant environment. This can be seen as a good thing: Even though they are not able to change their own environment, they can at least signal for others to change it for them.

However, this does does not always have to be desirable. Didden et al. [7] argue that challenging behaviour could be the result of unintentional operant conditioning. Challenging behaviour could be stimulated by the response from the caretakers. In proper environment creation, care should be taken to change the environment pro-actively, anticipating on moods before the onset of challenging behaviour, instead of responding to behaviours from clients.

Although quantitative results do not point towards a single clear explanation, remarks by caretakers and several incidents during the duration of the study do seem to indicate the environment that was created had a positive influence. During the brainstorm session with the caretakers some indicated that there were clients who really seemed to enjoy the sessions of the experiment. Some clients started to link the researcher to the event and became very excited when they were being picked up from the group. One such client is Bram1 :

Bram (Male, age 53, severe ID) spends his days in a group where music is played often and one of the other clients often screams very long and loudly. Bram always seemed to relax during the sessions, often (nearly) falling asleep. After a couple of weeks Bram knew the researcher and what it entailed when the researcher came to the group to pick him up. Bram would walk very quickly and ahead of the caretaker and researcher towards the experiment room. One time Bram walked out on an other activity he was doing and went to the experiment room on his own. He walked right in, opening several doors in the process and interrupting an other session. Caretakers indicated that Bram also showed less challenging behaviour. During the sessions he did not scream, nor show signs of aggression or self-injury. This positive reaction also occurred when he did exhibit challenging behaviour before he was picked up.

Although it did not happen often that clients walked into the room on their own accord, there were several other clients who also seemed to be able to relax so well they could fall asleep during the session. Some clients often neared that point, but kept themselves awake by checking to see if the caretaker was still there every now and then.

Relaxed was not the only state clients could be in. Every now and then there was a client that was enabled to be in an interested and playful mood. Taking the sound into their playfulness:

Daan (Male, age 23, mild ID) has a more mild form of ID than the other clients in the activities center. His challenging behaviour includes him being afraid of most people.

There are only a few caretakers he willingly interacts with. With those caretakers he has a playful relationship. They have their own jokes, that are often based on tv shows or commercials. In his playfulness Daan can create worlds in his head. He is still able

1To ensure anonymity this, and the other names used in this thesis, are aliases.

| 24


5.2. Remarks on our Methods

to distinguish real from imaginary. During the sessions Daan often stayed quite busy, especially in the beginning, joking around with the caretakers. Further into a session Daan would often calm down a bit. The first time Daan underwent a session of the experiment he received the beach condition. After a while he started pulling up his feet at certain moments. When his caretaker asked him what he was doing, Daan responded he had to keep his feet dry from the waves.

The example above illustrates nicely that clients do not necessarily have to be focussed on the sound or be relaxed. In the case of Daan he created his own conditions in which the sound was given a background status while he was joking around with the caretaker. The sound did influence Daan and took a place in his fantasy world. This seems to strengthen the idea that a pleasant sonic environment allows freedom of thought and action.

5.2 Remarks on our Methods

This study was conducted in a real world setting. It used the location at hand and had to be fit into the daily routine of clients and caretakers. This meant clients were taken from their usual setting to go into a strange environment. Comments on the assessment form placed under the heading Opmerkingen bij gedrag en stemming bij binnenkomst (remarks on behaviour and mood on entrance) indicate this could have had an influence. 11% of the remarks written down by caretakers mentioned the client having to adjust or finding it strange to be in experiment room al of a sudden.

Quite a few remarks also report clients initially being distressed or tense. Some caretakers specified that this negative mood started during the walk from the group to the experiment room.

The room in which the experimental setup was realised had two properties that likely had an adverse effect on this study. First it was not possible to ensure complete sound insulation from the surroundings. This not only led to sessions having to be rescheduled when workers were, for example, mowing the lawn, but it also meant that sometimes more incidental sounds, such as for example birds singing, were audible during the sessions. For four of the conditions this will not have had a large impact as those sounds were loud enough to mask birds from outside. The silent condition however was not always as silent as would have been ideal. Because sessions were only rescheduled when the noise from outside the room was very prominent and this was only the case for unpleasant sounds, sounds that influenced the sessions undergone silent condition were mostly pleasant. This could possibly explain why the silent condition led to moods that were more positive than expected.

The second issue with the room that was used is that it is an isolation room. This room had not been used for its intended purpose in this particular activities center. However, all rooms of this type look alike and until recently policy was often to subdue and isolate clients when they exhibited certain aggressive or self-injurious behaviour. Several of the clients who have been in the healthcare system for a longer time have experienced this policy. This led to several clients not wanting to enter the room at al. These clients were dropped from the experiment at the start.

There, however, also were a few clients who did not respond that badly, but who did indicate, or exhibit behaviour indicative of, being scared to be in the room. This will likely have influenced their response to the sonic environment. In at least one case the anxiety seems to have been so strong the client did not respond to the sound, or caretaker, at al:

Tess (Female, age 44, moderate ID) is a client that is attached to the group that works outside all day. They make rounds over the grounds of the care organisation, collecting bags with garbage and laundry. During meal and break times this group returns to

| 25


5.3. Futher Research

the activities center. Here Tess often listens to music using head phones. According to caretakers she really enjoys this and it calms her down when she is anxious. Based on this it was expected she would enjoy the sonic environments. However, Tess can show very difficult behaviour and in her years being under the care of different care organisations she has on multiple occasions been forced into isolation rooms when caretakers thought she was difficult to handle. Although she had never been in or near the isolation room used for this study, she immediately recognized what it was originally designed for and became very anxious. She reported being scared in the room.

Opening the door helped slightly, but not enough. During sessions Tess sometimes did mention she heard a certain sound. She was aware of the sound, but her anxiety about the room was too serious to allow her to relax.

An other major remark that has to be made is that, although sonic environments are normally present in the background, in this study the sound was present more in a foreground like manner.

Clients were taken from their routine and brought in a space where they had to acknowledge the sound. This could not be circumvented within the method chosen for this project. Some clients have some form of simple tasks, like making puzzles, they do during the day. However, some do nothing but sit on a couch all day while others work outside most of the time. It was not possible within the scope of this project to create meaningful activities for all clients involved in the project that would have also fit inside the experiment. To take away the differences in what clients were doing in the room a choice was made not to provide part of them with a task while others did nothing.

5.3 Futher Research

Parallel to this study several other studies into sonic environments and their (possible) role in the lives of people with intellectual disabilities are being conducted. In one of them researchers analyse the sonic environments currently present in the lives of the clients by making short (1 minute) recordings and having caretakers answer a few questions on what they think of the sound at that moment. An other, new project, focusses on registering the sounds in the homes of the clients. Researchers hope to develop an algorithm that can automatically classify the environment and events that occur. The goal of that project is to use the sound in the environment to predict outbursts of challenging behaviour and, ultimately, to provide a change in the sonic environment to counter the outburst before it happens. An intermediate research step here could be to, over the course of a week or so, monitor hourly averages of the sound quality in normal situations and then do the same but with a sound playing in the background. This would not, as in this study, provide observations per client, but it would provide more quantitative measurements.

A case could also be made that it would be worthwhile to further investigate the effects found for the silent condition. To study this an experiment similar to the one used in this study could be conducted. This time care should be taken to use a room that is completely insulated from sound from the rest of the building. This would ensure the silence would not be interrupted.

Because we are interested in the effect of (real world) sonic environments this would be a purely theoretical pursuit. In our normal, day-to-day, environments no sonic environments exist that are completely devoid of sound. Placing participants in a completely silent environment might even lead to feelings of unease not stemming from sound characteristics, but from the general lack of sound, which we are not used to. For future research on the influence of real-world sonic environments it would probably be better to use recordings of day-to-day surroundings of the participants as a baseline, instead of silence.

| 26


5.4 Conclusion

This project aimed to establish whether it is possible and beneficial to create the correct sonic environments for people with intellectual disabilities. Different sounds were used to create sonic environments. People with an intellectual disability were brought into these sonic environments and caretakers were asked to observe the behaviour of these persons.

To conclude an attempt is made to answer the three questions posed in section 1.1.

1. Can we create a sonic environment that helps persons with an intellectual disability to reach a pleasant state of being (in terms of core affect)?

It became apparent that it is indeed possible to create pleasant environments that allow these people to reach a pleasant state. However, what constitutes such an environment and what the exact role of sound in such an environment is, is still unclear.

It seems people with an intellectual disability require, more so than normal people, an environment where the different elements are in harmony. The definition of harmony, as formulated by Booi et al. [5], entails that different sensory modalities should complement each other to create an environment with meaningful elements, without a single perception being dominant. This fits with our observations that safety and pleasantness are strongly related to other people in the environment of the clients, such as their caretakers. These influences made it difficult to determine the exact influence of sound.

2. Which sounds enable this and what are the characteristics of these sounds?

Unfortunately it is not possible to give a definitive answer to this question. The results show that there is very little difference between the different sonic environments. Qualitative data seem to contain indications that the answer to this question, when found, will not be a simple answer. Some clients became more calm when experiencing forest or beach sounds, while others seemed to be most calm when there were more and louder sounds in the environment.

3. How does this compare to the original theory on appraisal and influence of sounds?

A difference, in terms of core affect, between the different sonic environments was not found.

Based on calmness and source characteristics of the sounds it was expected that the forest and beach conditions would allow a more relaxed state as compared to the other three conditions.

This was not the case. However, this and the indications that some clients prefer louder sounds over calmer sounds, and vice versa, is in accordance with the idea that complexity and affordances are subjective and vary for each individual. Not only do they vary between individuals, but complexity and affordances can also vary over time within one individual.

Also in line with the theory are indications that the influence of sound is a subconscious process. This was hinted towards by caretakers reporting sound as the most important factor for 50% of the clients that did not seem to respond to sound.

Even though no definitive answers to our research questions were found, the findings of this study should provide a basis on which to continue soundscape research with people with an intellectual disability. Findings, both from this study as well as personal experience by caretakers, are currently being utilized to improve the environment for clients at the activities center.

| 27



[1] T. C. Andringa and J. J. L. Lanser. How pleasant sounds promote and annoying sounds impede health: A cognitive approach. International journal of environmental research and public health, 10(4):1439–1461, 2013.

[2] T. C. Andringa and K. A. van den Bosch. Core affect and soundscape assessment: fore-and background soundscape design for quality of life. internoise 2013, 2013.

[3] T. C. Andringa, K. A. van den Bosch, and C. Vlaskamp. Learning autonomy in two or three steps: linking open-ended development, authority, and agency to motivation. Frontiers in psychology, 4, 2013.

[4] ¨O. Axelsson, M. E. Nilsson, and B. Berglund. A principal components model of soundscape perception. The Journal of the Acoustical Society of America, 128:2836, 2010.

[5] H. Booi and F. van den Berg. Quiet areas and the need for quietness in amsterdam. Interna- tional journal of environmental research and public health, 9(4):1030–1050, 2012.

[6] A. Chemero. An outline of a theory of affordances. Ecological psychology, 15(2):181–195, 2003.

[7] H. C. M. Didden, P. C. C. Duker, and D. M. Seys. Gedragsanalyse en-therapie bij mensen met een verstandelijke beperking. Elsevier Gezondheidszorg, 2003.

[8] R. Didden, P. Sturmey, J. Sigafoos, R. Lang, M. F. O’Reilly, and G. E. Lancioni. Nature, pre- valence, and characteristics of challenging behavior. In Functional Assessment for Challenging Behaviors, pages 25–44. Springer, 2012.

[9] S. Einfeld and E. Emerson. Intellectual disability. Rutter’s Child and Adolescent Psychiatry, Fifth Edition, pages 820–840, 2008.

[10] E. Emerson. Challenging behaviour: Analysis and intervention in people with severe intellectual disabilities. Cambridge University Press, 1st edition, 1995.

[11] E. Emerson. Challenging behaviour: Analysis and intervention in people with severe intellectual disabilities. Cambridge University Press, 2nd edition, 2001.

[12] E. Emerson and J. Bromley. The form and function of challenging behaviours. Journal of Intellectual Disability Research, 39(5):388–398, 1995.

[13] H. Evenhuis, M. Theunissen, I. Denkers, H. Verschuure, and H. Kemme. Prevalence of visual and hearing impairment in a dutch institutionalized population with intellectual disability.

Journal of Intellectual Disability Research, 45(5):457–464, 2001.

[14] C. Hatton. Epidemiology. In E. Emerson, C. Hatton, J. Bromley, and A. Caine, editors, Clinical Psychology and People with Intellectual Disabilities. Chichester: Wiley, 1998.

| 28



Background: Peers living in the same group form important interaction partners for people with profound intellectual and multiple disabilities (PIMD).. Given the severity of

Off-label use of antipsychotic medication in people with intellectual disabilities: adherence to guidelines, long-term effectiveness, and effects on quality of life..

Keywords behavioural determinants, direct support professionals, implementation, item response theory, people with intellectual disabilities, physical

Physical fitness and performance of daily activities in persons with intellectual disabilities and visual impairment: towards improving conditions for participation..

Physical fitness and performance of daily activities in persons with intellectual disabilities and visual impairment: towards improving conditions for participation..

Towards a person-centred approach for older people with intellectual disabilities: the use and effect of Dementia Care Mapping.. University

Towards a person-centred approach for older people with intellectual disabilities: the use and effect of Dementia Care Mapping2. University

This study provides a user perspective on assets for physical activity and healthy nutrition in intellectual disability care settings, and thereby also practical implications of