Physiological Interventions (page 3)

Sensory Activities

Difficulties with sensory input have long been associated with autism spectrum disorders. Early versions of the DSM listed sensory impairments as one of the diagnostic criteria (DSM-III), and anecdotal reports of both hyper-and hyposensitivity to environmental stimuli are common (Anzalone & Williamson, 2000). Descriptions of individuals with ASD who cover their ears when music is played or react to a generally considered light touch or mild odor as if it is painful are considered hypersensitive (Grandin, 1992; O’Neill & Jones, 1997). Individuals who act as though they are deaf or are nonreactive when a fire alarm goes off are considered hyposensitive (Anzalone & Williamson; Baranek, 2002). The repetitive or stereotypic behaviors exhibited by some individuals, such as waving fingers in front of the eyes, body rocking, or noncontextual vocalizations, are speculated to provide sensory input.

The percentage of individuals with ASD who display these atypical reactions to sensory stimuli remains unknown and is estimated to be between 42 and 88% (Baranek, 2002). Results from the implementation of The Sensory Profile (Dunn, 1999) with 86 individuals with Asperger syndrome and 86 diagnosed with autism, indicate that individuals with Asperger syndrome may have comparatively greater differences in the areas of emotional/social responses, emotional reactivity, and inattention/ distractibility compared with individuals diagnosed with autism (Myles et al., 2004). Sensory deficits have been hypothesized to be due to abnormalities in the limbic and cerebellar systems (Anzalone & Williamson).

Theorizing about the interactions between the environment and the individual’s nervous and sensory systems, and suggesting interventions based on these theories, has been considered the realm of occupational therapy (Miller-Kuhaneck, 2004). Occupational therapists study physiology and neurology and have engaged in debates regarding theories that describe the characteristics of autism spectrum disorders (O’Neill & Jones, 1997). Sensory integration therapy is based on the theory developed in the 1970s by Jean Ayres (1972), who worked with individuals with learning disabilities (Dawson & Watling, 2000). Intervention strategies based on her theory consist of planned sensory experiences such as swinging, deep-pressure touch, and tactile stimulation. In general, occupational-therapy-based activities are child-directed and are designed to promote the development of skills in the context of work, play, and adaptive behavior (Dawson & Watling).

The goal of the sensory integrative process is to address the following four As: (1) arousal level, (2) attention to the environment, (3) affect, and (4) action, or engagement in adaptive, goal-directed behavior (Anzalone & Williamson, 2000). Occupational therapists have recommended the use of a ball or specially designed chair for sitting in order to assist in maintaining attention or arousal, the use of a soft ball on the face for stimulation, and use of a weighted vest to provide deep pressure for calming. Research on the effects of these modifications on attention to task, decreases in problem behavior or tantrums, and displays of affect is limited.

In a recent study, the effects of touch or massage by parents at bedtime was evaluated for the effects on sleep problems and social relatedness, stereotypic behavior, and on-task behavior during bimonthly observations of play at preschool (Escalona, Field, Singer-Strunck, Cullen, & Hartshorn, 2001). The 10 participants in the experimental group slept better and were comparatively more attentive with less stereotypic behavior when they received massages. The authors conclude that the increase in attentiveness could be due to getting better sleep or enhanced parasympathetic activity (Escalona, et al.). Eleven children who received touch therapy comprised of rubbing with moderate pressure and smooth strokes for 15 minutes per day, 2 days per week for 4 weeks were observed less frequently as orienting to irrelevant sounds and exhibiting stereotypic behaviors compared to an attention control group. There were no differences in off-task behavior or touch aversion between the two groups (Field, et al., 1997).

Deep-pressure touch has been reported by Temple Grandin, a high-profile adult with autism, as a helpful strategy for calming down (Grandin, 1992). She reports that she created a Hug Machine that she used to apply deep pressure when desired. Deep pressure from the Hug Machine was evaluated for five children with autism on galvanic skin response (GSR) and parent ratings on created subscales from items off the Conners Parent Rating Scale compared with seven children who received no deep pressure or a placebo control (Edelson, Edelson, Kerr, & Grandin, 1999). The authors indicate that the low numbers greatly reduced the power of the statistics, but they claim that there was a marginally significant finding on the GRS in support of the deep pressure and that parents rated their children who received deep pressure lower on the created Tension scale (Edelson, et al.). More research, with larger numbers of students with ASD and in educational programs, is needed regarding the effects of massage or deep pressure on behaviors including attention to tasks presented for learning.

Sensory activities that modulate the four target areas can be considered a “sensory diet” (Anzalone & Williamson, 2000). The purpose of a sensory diet is to help the individual to attain and maintain optimal arousal states or to provide sensory input that is sufficiently consistent and intensive to change sensory processing capacities (Wilbarger, 1995). Similar to a nutritional diet, a sensory diet involves planning for someone’s individual needs (Wilbarger). It is recommended that activities be implemented throughout the day with “sensory tune-ups” scheduled at key times (Wilbarger). Educators typically schedule sensory activities at predetermined times of the day because it is not possible to accurately determine someone else’s sensory needs.

Wilbarger and Wilbarger (1991) described a strategy called the sensory summation technique that involves a combination of brushing the arms, back, and legs rigorously with a surgical scrub brush followed by 10 gentle joint compressions to the arm and leg joints, concluding with sensory input to the fingers and toes. This procedure, referred to as the Wilbarger Protocol, has been recommended by occupational therapists to be implemented by public school preschool teachers multiple times throughout the day. There is no published research on the effects of the sensory summation technique with individuals with autism spectrum disorders, and only one case study (Stagnitti, Raison, & Ryan, 1999) reports outcomes of a sensory diet that included the Wilbarger Protocol (Baranek, 2002).

Parents report the use of sensory integration therapy in high percentages: 56% of those surveyed enrolled in intensive behavior analytic treatment (Smith & Antolovich, 2000): 40% of those surveyed from participation in early intervention programs (Hume, et al., 2005), and 38.2% from the Internet survey (Green et al., 2006). It is important to note that even though many individuals with autism spectrum disorders who attend public schools receive services from occupational therapists to address sensory issues, there has been relatively little systematic, controlled research on the effectiveness of various interventions (Dawson & Watling, 2000; Helflin & Alaimo, 2006; O’Neill & Jones, 1997). Regardless of the form of sensory activity evaluated, it would be important to control for the typical one-on-one attention that students with ASD receive during the implementation of sensory activities. Recent policies that emphasize the use of evidence-based practices has resulted in a critique of current practices used by occupational therapists and a call for empirical research on sensory-based interventions by school psychologists (Shaw, 2002), special educators (Goldstein, 2000), and leaders in the field of occupational therapy (Baranek, Parham, & Bodfish, 2005; Ottenbacker, Tickle-Degnen, & Hasselkus, 2002).

We have tended to rely on other forms of evidence, such as the voice of an expert, uncritical acceptance of the findings of a single published study or published manual, and reliance on our own previous experiences and the experiences around us. . . . We believe that an urgent need exists for all of us in occupational therapy to develop and use the skills necessary to plan treatment strategies for individual clients based on what is supported by evidence. (Ottenbacker et al., 2002, p. 247)