Sensorium 6: Changing Brain Arousal

Arousal is a dynamic, ever-changing process related to direct and indirect responses to internal and external stimuli. We are constantly adjusting to our environment. Arousal is modified and altered through: (a) registration of the stimulus at the brain; (b) the habituation process of the nervous system, its ability to depress synaptic transmission to repeated non-noxious irrelevant stimuli; and (c) the neuron’s ability to react by an increased response to stimuli that is intense (Pfaff, 2006).

The MSE experience affects motivation and functional attention by changing brain arousal through the senses and sensory stimulation. The key is finding the combination of sensory input for an individual that allows the individual to take control and achieve a healthy level of stress and brain arousal. This allows self-regulation, motivation, organization, and integration to take place for the individual. The optimal level of arousal is unique to each individual and can be referred to as the sensory diet.

A sensory diet is the multi sensory experiences that one prefers to seek on a daily basis to satisfy one’s need for sensory interests and needs to produce self-regulation (Messbauer, 2006). The sensory diet provides an optimal combination of sensations at the appropriate intensity for the individual. A sensory diet is our attempt to modify stressors and control arousal levels and is unique to each of us; it is based on both internal unconscious processes and developing, ongoing life experiences–a cognitive process that leads to personal preferences. Both the sensory diet and personal preferences combine to establish motivation (Messbauer, 2006).

The brain and nervous system have a capacity to determine if the stimulus is: (a) relevant, (b) valued, and (c) modulated (referring to the ability of the nervous system to regulate its own activity). Arousal increases with intensity, complexity, unexpectedness, incongruity, affective meaning, and novelty. Arousal decreases with constancy, uncertainty, repetition, familiarity, and neutrality (Messbauer, 2006; Pfaff, 2006). Alpha/theta waves decrease arousal and beta waves increase arousal (see Table 1).

To achieve the right level of brain arousal, the MSE room must be a match with the individual’s sensory preferences (or sensory diet) based on his or her historical and significant experiences. The level of the individual’s arousal, agitation and/or anxiety, or their state of withdrawal, is matched to the degree, intensity, and frequency of sensory input. The sensory input is then carefully orchestrated to work with the person’s sensory interests and choices. The stimulation is then increased or decreased to meet the individual’s need or desired outcome (Messbauer, 2006). To change arousal, the speed of the level that the child is currently at need to be matched, for example, slow if the child is withdrawn or fast if the child is hyper or very active (Messbauer, 2006).

The equipment must be linked to controls that will allow for changes in duration and frequency. These controls need to be operable by both the facilitator and the user, allowing the facilitator to ultimately control the entire environment to allow for the contingencies the environment will eventually offer the individual. Allowing the user to initially select the amount (intensity, frequency, and duration) of sensory input allows the facilitator to observe which sensory system is approached and which is avoided by the individual as they explore specific equipment. This is a period in which the individual learns to perceive the environment as comfortable, fun, and safe. If the room is not ever-changing it can induce sleep or boredom, especially after sufficient time has passed and any opportunity for further exploration is gone. Thus, both equipment and room need to be used to produce subtle changes in arousal to maintain an individual’s level of wakefulness. Switches allow for a consistent, but constantly changing environment.

The main objective is for the user to use their senses to learn self-regulation and become more aware of how they are feeling emotionally. It is important that the user does not sleep in the MSE. For example, if the goal of the user is to lower brain arousal or produce relaxation the facilitator can help the individual become aware of that state and how it feels. If the user goes into a sleep state they will not be able to learn from the process. The facilitator needs to take the temporary pleasurable feeling and help the individual identify, learn from, and repeat it. To avoid a user sleeping the facilitator should provide a changing environment. Furthermore, it is not only the amount of stimulation that is important, but also variation in the stimulation, i.e., monotonous unchanging stimulation can be as negative as no stimulation (Pinkney, 1997). Never turn the whole room on and leave it going unchanged forever. A facilitator can change the environment by changing equipment, changing the amount of control, changing music, and optimizing the use of the effects projector.

Changing Equipment

The MSE equipment is designed to have change built into it. The number of variables of each piece of equipment is predetermined by its design and function. The first variable is that equipment can be turned off and on. A facilitator has the ability to sequence specific equipment, i.e., determine an order of turning on specific equipment in a specific sequence. The facilitator also has control of dimming the lights in the room and how much darkness will control general arousal and state of wakefulness. Thus, controlling the equipment and the entire room can prevent sleeping.

Changing the Amount of Control

The facilitator can change the control features to increase or decrease the motivation to continually explore a single piece of equipment or to explore a different piece. For example, if the user has been exploring the bubble tube, and is losing interest, create a change by turning the controller to a toggle mode where the user has to press and hold a button to make the bubbles in the bubble tube work. Some equipment you can adjust the speed. The change can be very subtle, which is often better. Sometimes a large change may be abrupt and startling (Messbauer, 2006).

Changing Music

The facilitator can control the type and volume of music. Changing the tempo of the music will generally change brain arousal. Adjusting volume will also change states of wakefulness. This can be very subtle (Messbauer, 2006).

Optimize the Use of the Effect Projector

Optimize the use of the effect projector by varying the visual effects. Change location of the rotating effect wheel. For example if it has been on the wall, spot it on the floor, or use the prism to make a subtle change of the visual effect. The projector should be mounted for easy access so wheels can easily be changed and varied. The facilitator can bounce a projected image onto some other piece of equipment or the mirrors, making the visual image more complex and interesting. The effect projector is a major piece of equipment for changing brain arousal. When the image from the projector is turned on it will become a focal point, a dominant element that draws the eye and unconscious awareness of change if it is subtle. Remember that general arousal increases with intensity, complexity, unexpectedness, incongruence, affective meaning, and novelty. General arousal decreases with consistency, repetition, familiarity (predictability), and neutrality.


The main ingredient of development and learning is sensory stimulation that allows a human being to apprehend the environment through senses and respond to it. Motivation to be involved in one’s daily activities depends largely on the senses. MSE provides powerful forms of sensory stimulation for individuals who are isolated from sensory experiences due to limitations of movement, vision, hearing, cognitive ability, constrained space, behavioral difficulties, perception issues, pain, and other problems that create obstacles to their everyday learning.

The intention is to provide individualized, gentle sensory stimulation in a non-threatening environment without the need for higher cognitive processes and incorporating personal circumstances, such as preferences and cultural diversity. The leading outcomes are to improve learning, social interactive skills, inclusion, and quality of life. The MSE concept is based on the idea that everyone has a right to quality leisure and recreation.

In conclusion, to improve learning, enhance development and the quality of life a multi sensory stimulation may be in a natural or artificial environment as long as the multi sensory simulation is consistent, and frequent. The most effective MSE must consider room design and equipment selection, trained facilitators and techniques for changing brain arousal (see figure 3).