The conceptual framework has been substantiated through an integrated review of the literature and research as well as discussion with MSE experts. A conceptual framework explains the possible connection between the variables and interrelated theory.
New developments in neurology may address why MSE provides such positive benefits for children and adults. Through MSE, sensory stimulation produces brain arousal, which can be either decreased or increased for individuals with profound intellectual challenges. Increasing brain arousal can make an individual more alert, active, and focused. Neurons fire and the brain is exercised. For individuals who are agitated, hyperactive, or stressed, decreasing brain arousal can have a calming effect, reducing stress and again allowing an individual to be more focused. Changing brain arousal through sensory stimulation can change social, emotional, and adaptive behaviors, reduce stress, and improve learning. Changes in brain arousal can also improve cognition as well as communicative and motor development. The results of the findings from the literature and research will be discussed in a conceptual framework dealing with the elements of an MSE that evolved into an MSE delivery model.
Based on the literature, research, and emerging themes in MSE and neuroscience, an MSE delivery model was developed to improve physiological and psychological outcomes for populations with various disabilities. Based on the findings, MSE should be: (a) artificially created but include the natural environment as well; (b) devoted to stimulating all the senses, (c) safe, comfortable, and predictable, (d) designed to empower the individual by providing self-choice, (e) a demand-free leisure activity rather than a controlled therapy; (f) passive and interactive with the interactive approach providing cause-and-effect relationships, (g) have trained facilitators , and (h) affect brain arousal to heighten awareness and/or increase relaxation. The development of the model is integrated into the following propositions for further testing and development of MSE theory.
Proposition 1 – Artificially Created Supported by the Natural Environment
A multi sensory simulation can be obtained from the natural environment. During a walk on the beach an individual’s tactile senses are stimulated through the feel of the warm sun, a balmy breeze, and sand on their feet. The sound of the ocean waves and birds singing provide auditory feedback; natural sunlight and the glisten of the sun on the water provide visuals, among other experiences. While an MSE can be a natural environment, it is important that individuals with cognitive challenges are constantly and consistently provided elements of artificial or engineered multi sensory stimulation. An engineered environment may provide more focus or additional sensory stimulation for people who, due to their disabilities, are not spontaneously able to seek such stimulation on their own (Pagliano, 1999). Various limitations may impede the ability of an individual to interact with a natural environment in a meaningful way. For example, a blind child may not have the ability to see light in a natural environment; however, in an artificially created MSE, certain light illuminating equipment, such as the fiber optic, may stimulate the optic nerves (Pagliano, 1999). Thus, an individual with a disability may require an engineered environment to help make it meaningful and rewarding or they will withdraw emotionally and physically to the security of their own internal sensation (Pagliano, 1999; Messbauer, 2006). In an artificially created environment the sensory stimuli can be intensified or reduced and provided in a constant and consistent manner, offering more stimuli than the natural environment. For children with disabilities the natural environment may seem chaotic and unpredictable, yet through the use of an artificially created MSE, a child’s natural environment becomes less chaotic as he or she learns how to control sensory input from their natural external world. An individual in the MSE quickly learns how to internalize various sensory stimulation that provides a “feel good,” calm, more alert, and waking state. Thus, it is also important to provide the opportunity for individuals with intellectual disabilities to also interact with the natural environment. The user then learns, unconsciously, how to work more effectively with the natural environment (outside world) to reach this same positive “feel good” state. Ultimately it is the multi sensory environment that will lead to self-discovery for the individual (Messbauer, 1999).
Proposition 2 – Devoted to Stimulation of all the Senses
Learning and motivation depend largely on the senses. Adequate multi sensory stimulation of all the senses produced in sufficient frequency, intensity, and duration excites and exercises the brain, improves its organization, heightens awareness, and permits increased functional activities. By working toward a better organized, stronger, and more efficient nervous system, individuals become better able to demonstrate and access their true potential. Intense periods of sensory stimulation that use repeated movement, sound, touch, and visual exercises help slowly to create new pathways in the brain where they were damaged or underdeveloped (DeBoer & Sutanto, 1997; Robbins, 2000). Multimodal stimulation (stimulation of three or more senses) has more dramatic results than unimodal stimulation (stimulation of one sense) (Ansell, 1991; Kater, 1989; Gersten, Baker, & Lloyd, 2000). Those in multi sensory environments have more recall with better resolution that lasts longer, evident even 20 years later. Additionally, research has shown that exercise (Bachman & Fuqua, 1983; Bachman & Sluyter, 1988; Baumeister & MacLean, 1984) and repetitive movements in physical activities involving kinesthetic stimulation have led to positive effects on behavioral challenges and improved brain function (Long & Haig, 1992; Morrissey, Franzini, & Karen, 1992). Animal studies have shown that voluntary exercise and movement enhances cognitive performance and protects from brain injury and disease (Friedland, Fritsch, & Smyth, 2001; Van Praag, Christien, Sejnowski, & Gage, 1999). Thus, sensory stimulation needs to also offer kinesthetic, proprioceptive and vestibular stimulation.
Proposition 3 – Safe, Comfortable, Consistent, and Predictable
Aimed at changing brain arousal, an MSE should be safe, comfortable, consistent, providing constant sensory stimulation, and producing an atmosphere of trust. All elements of physical comfort, such as temperature, lighting, noise levels, or seating options, must be adjustable to make the MSE comfortable. Children and adults with multiple disabilities need opportunities for play, relaxation, and enjoyment in a quiet yet stimulating environment. A user-friendly environment that is comfortable and constant is required to facilitate learning and development in the MSE. Cognitive learning models suppose that people self-regulate their environments and actions, and that new behaviors are learned and maintained by those interactions between the person and their environment. This can occur only in a safe and comfortable environment. The importance of consistency, initially, is to reduce stress and anxiety associated with the inability to adapt to the natural environment and all of the demands in the natural environment. The natural environment requires the individual to process multiple channels of information, both conscious processes such as cognitive demands made by people, places, and activities, and unconscious process demands, those environmental factors that impact internal functions of the brain and body put on an individual by the ever-dynamic, changing environment (Messbauer, 2006).
Proposition 4 – Designed to Empower through Self-choice
A demand-free, self-choice environment empowers an individual, enhancing his/her self-determination. Self-determination is critical in predicting various performance and satisfaction outcomes (Fornes, 2008). Self-determination theory (SDT; Deci, 1992) is a general theory of human motivation concerned with the development and functioning of personality within social contexts. The theory focuses on the degree to which human behaviors are self-determined or the degree to which people endorse their actions by engaging in the actions with a full sense of choice (Ryan & Deci, 2000). “To be self-determining is to engage in an activity with a full sense of wanting, choosing, and personal endorsement” (Deci, 1992, p. 44). Self-determination is viewed as a fundamental human right to govern one’s life without unnecessary interference from others (Deci, 1992). Self-determination contributes to educational and work goals by increasing self-sufficiency, autonomy, and valued life outcomes like community integration, independent living, and inclusion (Fornes, 2008).
Individuals with severe/profound and multiple disabilities often have little or limited opportunity to exert control over their environment. As a result, they can feel helpless, lose confidence that they are able to exert any influence on their environment (even when they are able to take some level of control), and become withdrawn and apathetic. In effect, they learn to be more helpless than their disabilities actually make them. In an MSE, individuals are given the opportunity to exert and experience control over their environment. This may be through directed interaction with the equipment, through the use of a specially adapted remote control, or by communicating their preference to a facilitator. Through this experience, individuals are given the feeling of independence and choice (Pinkney, 1997).
Proposition 5 – A Demand-Free Activity
Most providers of MSE today use MSE mainly as a non-directive, demand-free, leisure, recreational activity, and/or educational tool that has been identified to have therapeutic value (DeBunsen, 1994; Hope, 1998; Hulsegge & Verheul, 1987; Lancioni, Cuvo, & O’Reilly, 2002). The non-directive, leisure nature of MSE has been emphasized with relaxation, enjoyment, learning, and facilitation of interpersonal relationships (Cavet & Mount, 1995), as well as improvement in brain functioning (Vargas & Camilli, 1999). In a demand-free, self-choice environment, a facilitator acts only as a guide introducing the equipment to the child (Hogg & Cavet, 1995). The child chooses what equipment provides the most pleasure and enjoyment.
Using an MSE requires no memory or cognitive reasoning ability. This removes demands on the individual to understand what they are experiencing, thus reducing the tendency for them to feel confused and to withdraw. In addition, the stimuli presented in an MSE are unpatterned, and thus less demanding of attention and cognitive processing ultimately reducing the demands and stress that individuals are under and encouraging more positive and appropriate behaviors (Pinkney, 1997).
An analysis of studies on the effects of the use of a multi sensory environment showed more positive outcomes when MSE is used as a demand-free, self-choice activity rather than as a controlled therapy, such as Sensory Integration or SI (Giza, Griesbach, & Hovda, 2005; Houghton, Douglas, & Brigg, 1998; Jacobson, Foxx, & Mulick, 2005; Lancioni, Cuvo, & O’Reilly, 2002). Furthermore, voluntary wheel-running in mice results in increases in plasticity molecules and cognitive enhancement (Jacobson et al., 2005). On the other hand, forced treadmill running did not improve cognition, probably due to stress. Based on this research, MSE as a demand-free activity is more likely to produce positive therapeutic outcomes than when used as a controlled therapy.
Proposition 6 – Interactive and Passive
MSE’s initial focus was to be utilized more as a passive approach providing relaxation and exploration through sensory stimulation. MSE was an activity to provide enjoyment and pleasure to children with profound disabilities. MSE has recently moved in the direction of a more interactive program with an emphasis on learning as well. The two approaches (passive and interactive) can be used together to create a more flexible use of the space (Hirstwood, 1994; Hirstwood & Smith, 1996).
The initial experience of a passive MSE is very novel and thus increases arousal; however, novelty does wear off. A person will adapt to any environment that is held constant. It becomes predictable and as a result may become boring. Both predictability and constancy are hallmarks to promote anti-stress and the relaxation process. They lower general arousal, but can also create monotony and boredom resulting in sleep. It is important not to encourage sleep. If a person sleeps they are unable to learn from their environment. To maintain some level of relaxed wakefulness and exploration, subtle changes can take place in the room and equipment through an interactive approach. To produce changes in arousal and to maintain the individual’s level of wakefulness, a facilitator can turn on/off different pieces of equipment, change its color, change the music or the volume, or add more interactivity to the room.
Proposition 7 – Trained Facilitators
A key determinant of an effective MSE experience is the facilitator who serves as the first stimulus and guides the user through the MSE experience. (Haggar & Hutchinson, 1991; Henning, 1994; Hulsegge & Verheul, 1987). The facilitator provides empathetic interaction, not interfering with the person’s choice and pace, and guides the person toward sensory stimuli and engagement of objects (Hulsegge & Verheul, 1987). The most important thing in training caregivers is that they are not superior to the user, but equals who both have something to learn from the other. It is possible to give the caregivers the “challenge” to find out what their personal user’s talent may be by giving support, not direction.
A facilitator is a significant person to the individual and, therefore, knows him/her well. The facilitator can be a parent, a sibling, a personal assistant, therapist, or teacher (Andersson & Johansson, 2006). The facilitator must (a) be empathetic and caring, (b) have an understanding of the user’s sensory interests, and (c) know how to introduce the sensory stimulation to the user to affect brain arousal and brain synchronization that leads to increased enjoyment, focus, motivation, and learning. It is important to have an understanding of the individual’s likes and dislikes to avoid any sensory overload (too much stimulation). While this is usually not an issue for low functioning individuals that require multiple forms of stimulation in order to achieve higher awareness and functional activity, it can be an issue for children who have sensory processing issues. Thus, it is important to understand a child’s sensory processing issues and sensory needs.
Proposition 8 – Affect Brain Arousal through MSE
There are three premises to brain arousal and the well-being of an individual: (a) Central to quality of life is cognition, brain activity, and emotional function; (b) Central nervous system arousal is fundamental to all cognition, brain activity, and emotional function; (c) The core to increasing one’s brain arousal is sensory stimulation (Pfaff, 2006). Through sensory stimulation, brain arousal is increased and improves cognition (through alertness, attention, and orientation) and emotion (through temperament, mood, and feelings). The strength of a learned response depends on the arousal and drive of the individual (Pfaff, 2006). Brain arousal provides the fundamental force that makes animals and humans active and responsive, so they will perform instinctive behaviors or learned behaviors directed toward goal objectives (Hinde, 1966). MSE promotes changes in arousal levels and affects drive and motivation through changes in neurochemistry (Hotz et al., 2006). Brain arousal is higher in those who are: (a) more alert to multi sensory stimuli, (b) more motor active, and (c) more reactive emotionally (Pfaff, 2006). Arousal is a dynamic changing process related to direct and indirect responses to internal and external stimuli (Messbauer, 1999). For a human to be aroused, there must be some change in the environment. If there is change, there must be some uncertainty about the state of the environment (Kagan, 2007; Pfaff, 2006). Brain arousal increases with intensity, complexity, novelty, unexpectedness, inconsistency, infrequency, changing environments, incongruence, and the unusual.
High degrees of novelty, uncertainty, and unpredictability have high information content and promote brain arousal (Kagan, 2007; Pfaff, 2006; Shannon, 1948). The more uncertain we are about the occurrence of an event or action, the more information is transmitted when the event or action does happen (Shannon, 1948). Similarly, the more uncertain we are about an action or event, the more brain arousal is produced. For example, there are two events, the waving of a red or blue flag (Pfaff, 2006). If the red flag is waved all the time and the blue flag not at all, no information is transmitted by either flag, nor is there any brain arousal. However, if the flag selection is random, with a 50:50 chance of either flag being selected, information being transmitted is unpredictable and brain arousal is increased. Information conveys peaks when two probabilities are equal – that is, when the observer is least able to predict what will happen, the uncertainty, the surprise, and the information content are at their highest. Disorder maximizes information flow and increases brain arousal. At the opposite extreme, perfect order minimizes information flow and brain arousal. It is clear that in a monotonous environment, lacking change, a human or an animal will lose arousal and become less alert, resulting in failure to thrive. Arousal can be decreased with constancy, repetition, familiarity, and neutrality. The optimal level of arousal is unique to each individual and is based on their sensory needs and interests.
Based on the conceptual framework, an MSE delivery model was developed as illustrated in Figure 4. The delivery model of an engineered multi sensory environment consists of three hierarchal steps. The first step is to provide a physical space (room design and equipment selection) that is safe, comfortable, and engineered to provide consistent and constant multi sensory stimulation. The second step is a trained facilitator who has an understanding of the individual’s sensory interests and provides demand-free, self-choice opportunities to empower and increase self-determination. The third step is to provide techniques for utilizing the room and equipment to facilitate change in brain arousal, behavior, and motivation.