Sensory processing and integration problems exist when sensory signals do not result in appropriate responses (Miller, Anzalone, Lane, Cermak, & Osten, 2007Miller, L. J., Anzalone, M. E., Lane, S. J., Cermak, S. A., & Osten, E. T. (2007). Concept evolution in sensory integration: A proposed nosology for diagnosis. American Journal of Occupational Therapy, 61(2), 135–140. doi:10.5014/ajot.61.2.135). A person with sensory impairments finds it difficult to process and act upon information received through the senses, which creates challenges in performing everyday tasks and daily routines (Bar-Shalita, Seltzer, Vatine, Yochman, & Parush, 2009Bar-Shalita, T., Seltzer, Z. E., Vatine, J.-J., Yochman, A., & Parush, S. (2009). Development and psychometric properties of the Sensory Responsiveness Questionnaire (SRQ). Disability & Rehabilitation, 31(3), 189–201. doi:10.1080/09638280801903096; Bundy, Shia, Qi, & Miller, 2007Bundy, A. C., Shia, S., Qi, L., & Miller, L. J.(2007). How does sensory processing dysfunction affect play? American Journal of Occupational Therapy, 61(2), 201–208. doi:10.5014/ajot.61.2.201; Cohn, Miller, & Tickle-Degnen, 2000Cohn, E. S., Miller, L. J., & Tickle-Degnen, L. (2000). Parental hopes for therapy outcomes: Children with sensory modulation disorders. American Journal of Occupational Therapy, 54(1), 36–43. doi:10.5014/ajot.54.1.36; Cosbey, Johnston, & Dunn, 2010Cosbey, J., Johnston, S. S., & Dunn, M. L.(2010). Sensory processing disorders and social participation. American Journal of Occupational Therapy, 64(3), 462–473. doi:10.5014/ajot.2010.09076). Motor clumsiness, behavioral problems, anxiety, depression, school failure, and other impacts may result if the symptoms are not treated effectively (Miller, 2006Miller, L. J. (2006). Miller function and participation scales manual. San Antonio, TX: Pearson.).
The standard treatment for children with sensory processing challenges is individual occupational therapy (OT) designed to enhance the child’s ability to participate in daily activities and routines. The method used for treatment is individually defined and involves the remediation of underlying sensory impairments that enable participation in daily life at home and in education-related activities at school. Typically session duration is 30 to 50 minutes, occurring two to three times per week (Miller, Schoen, James, & Schaaf, 2007Miller, L. J., Schoen, S. A., James, K., & Schaaf, R. C. (2007). Lessons learned: A pilot study on occupational therapy effectiveness for children with sensory modulation disorder. American Journal of Occupational Therapy, 61(2), 161–169. doi:10.5014/ajot.61.2.161; Pfeiffer, Koenig, Kinnealey, Sheppard, & Henderson, 2011Pfeiffer, B. A., Koenig, K., Kinnealey, M., Sheppard, M., & Henderson, L. (2011). Effectiveness of sensory integration interventions in children with autism spectrum disorders: A pilot study. American Journal of Occupational Therapy, 65(1), 76–85. doi:10.5014/ajot.2011.09205; Schaaf et al., 2013Schaaf, R. C., Benevides, T., Mailloux, Z., Faller, P., Hunt, J., Van Hooydonk, E., & Kelly, D. (2013). An intervention for sensory difficulties in children with autism: A randomized trial. Journal of Autism and Developmental Disorders. doi:10.1007/s10803-013-1983-8). However, anecdotal evidence and intervention studies suggest that intensive programs produce more significant and lasting improvements (Granpeesheh, Tarbox, & Dixon, 2009Granpeesheh, D., Tarbox, J., & Dixon, D. R. (2009). Applied behavior analytic interventions for children with autism: A description and review of treatment research. Annals of Clinical Psychiatry: Official Journal of the American Academy of Clinical Psychiatrists, 21(3), 162–173.). Sound-based intervention is one form of intensive therapy that is sometimes offered to children with sensory impairments by clinic and school-based occupational therapists to supplement traditional approaches (Bazyk, Cimino, Hayes, Goodman, & Farrell, 2010Bazyk, S., Cimino, J., Hayes, K., Goodman, G., & Farrell, P. (2010). The use of therapeutic listening with preschoolers with developmental disabilities: A look at the outcomes. Journal of Occupational Therapy, Schools, & Early Intervention, 3(2), 124–138. doi:10.1080/19411243.2010.491013; Hall & Case-Smith, 2007Hall, L., & Case-Smith, J. (2007). The effect of sound-based intervention on children with sensory processing disorders and visual–motor delays. American Journal of Occupational Therapy, 61(2), 209–215. doi:10.5014/ajot.61.2.209). Also referred to as auditory programs, this form of treatment has widespread use but with limited empirical validation.
Effects of Auditory Programs
Previous treatment effectiveness research for children with sensory processing challenges has focused on sensory integration treatment to address the individualized needs of the child (May-Benson & Koomar, 2010May-Benson, T. A., & Koomar, J. A.(2010). Systematic review of the research evidence examining the effectiveness of interventions using a sensory integrative approach for children. American Journal of Occupational Therapy, 64(3), 403–414. doi:10.5014/ajot.2010.09071; Miller et al., 2007Miller, L. J., Anzalone, M. E., Lane, S. J., Cermak, S. A., & Osten, E. T. (2007). Concept evolution in sensory integration: A proposed nosology for diagnosis. American Journal of Occupational Therapy, 61(2), 135–140. doi:10.5014/ajot.61.2.135; Pfeiffer et al., 2011Pfeiffer, B. A., Koenig, K., Kinnealey, M., Sheppard, M., & Henderson, L. (2011). Effectiveness of sensory integration interventions in children with autism spectrum disorders: A pilot study. American Journal of Occupational Therapy, 65(1), 76–85. doi:10.5014/ajot.2011.09205; Schaaf et al., 2013Schaaf, R. C., Benevides, T., Mailloux, Z., Faller, P., Hunt, J., Van Hooydonk, E., & Kelly, D. (2013). An intervention for sensory difficulties in children with autism: A randomized trial. Journal of Autism and Developmental Disorders. doi:10.1007/s10803-013-1983-8; Watling, Deitz, Kanny, & McLaughlin, 1999Watling, R., Deitz, J., Kanny, E. M., & McLaughlin, J. F. (1999). Current practice of occupational therapy for children with autism. American Journal of Occupational Therapy, 53(5), 498–505. doi:10.5014/ajot.53.5.498). However, since occupational therapists often use auditory programs that involve listening to processed musical selections designed to supplement other sensory-based strategies (Bazyk et al., 2010Bazyk, S., Cimino, J., Hayes, K., Goodman, G., & Farrell, P. (2010). The use of therapeutic listening with preschoolers with developmental disabilities: A look at the outcomes. Journal of Occupational Therapy, Schools, & Early Intervention, 3(2), 124–138. doi:10.1080/19411243.2010.491013; Hall & Case-Smith, 2007Hall, L., & Case-Smith, J. (2007). The effect of sound-based intervention on children with sensory processing disorders and visual–motor delays. American Journal of Occupational Therapy, 61(2), 209–215. doi:10.5014/ajot.61.2.209), evaluation of their effectiveness is warranted. Auditory programs are growing in popularity and are used in addition to traditional OT because services can speed progress and can be implemented at home or school, thus, increasing intensity of service (Bazyk et al., 2010Bazyk, S., Cimino, J., Hayes, K., Goodman, G., & Farrell, P. (2010). The use of therapeutic listening with preschoolers with developmental disabilities: A look at the outcomes. Journal of Occupational Therapy, Schools, & Early Intervention, 3(2), 124–138. doi:10.1080/19411243.2010.491013; Carley, 2013Carley, C. (2013). Sound therapy: A complementary intervention for individuals with sensory integration and processing disorders, part I. Sensory Integration Special Interest Quarterly, 36(1), 1–4.; Hall & Case-Smith, 2007Hall, L., & Case-Smith, J. (2007). The effect of sound-based intervention on children with sensory processing disorders and visual–motor delays. American Journal of Occupational Therapy, 61(2), 209–215. doi:10.5014/ajot.61.2.209; May-Benson, Carley, Szklut, & Schoen, 2013May-Benson, T. A., Carley, C., Szklut, S., & Schoen, S. A. (2013). Sound therapy: A complementary intervention for individuals with sensory integration and processing disorders part II. Sensory Integration Special Interest Section Quarterly, 36(2), 1–4.; May-Benson & Koomar, 2010May-Benson, T. A., & Koomar, J. A.(2010). Systematic review of the research evidence examining the effectiveness of interventions using a sensory integrative approach for children. American Journal of Occupational Therapy, 64(3), 403–414. doi:10.5014/ajot.2010.09071).
In spite of the evidence supporting the beneficial effects of listening to music (Jing & Xudong, 2008Jing, L., & Xudong, W. (2008). Evaluation on the effects of relaxing music on the recovery from aerobic exercise-induced fatigue. Journal of Sports Medicine and Physical Fitness, 48(1), 102–106.; Labbé, Schmidt, Babin, & Pharr, 2007Labbé, E., Schmidt, N., Babin, J., & Pharr, M. (2007). Coping with stress: The effectiveness of different types of music. Applied Psychophysiology and Biofeedback, 32(3–4), 163–168. doi:10.1007/s10484-007-9043-9; Lai & Good, 2005Lai, H.-L., & Good, M. (2005). Music improves sleep quality in older adults. Journal of Advanced Nursing, 49(3), 234–244. doi:10.1111/j.1365-2648.2004.03281.x; Overy, 2003Overy, K. (2003). Dyslexia and music: From timing deficits to musical intervention. Annals of the New York Academy of Sciences, 999, 497–505. doi:10.1196/annals.1284.060; Sarnthein et al., 1997Sarnthein, J., Vonstein, A., Rappelsberger, P., Petsche, H., Rauscher, F. H., & Shaw, G. L. (1997). Persistent patterns of brain activity: An EEG coherence study of the positive effect of music on spatial-temporal reasoning. Neurological Research, 19(2), 107–116.), controversy still exists regarding the effects of therapeutic auditory programs that use acoustically modified music. A meta-analysis conducted in 1999 (Gilmor) reported positive gains in linguistic skills, psychomotor skills, personal and social adjustment skills, auditory skills, and cognitive skills following use of a specific type of auditory program called the Tomatis Method. However, the conclusions from the meta-analytic study were limited by the characteristics of the original studies. A more recent study of the Tomatis approach (Corbett, Shickman, & Ferrer, 2008Corbett, B. A., Shickman, K., & Ferrer, E.(2008). The effects of Tomatis sound therapy on language in children with autism. Journal of Autism and Developmental Disorders, 38(3), 562–566. doi:10.1007/s10803-007-0413-1) did not show statistically significant differences between the placebo and Tomatis treatment. Yet this study has also been criticized for methodological flaws (Gerritsen, 2010Gerritsen, J. (2010). The effect of Tomatis therapy on children with autism: Eleven case studies. International Journal of Listening, 24(1), 50–68. doi:10.1080/10904010903466378). Although not a scientifically rigorous study, Ross-Swain (2007Ross-Swain, D. (2007). The effects of auditory stimulation on auditory processing disorder: A summary of the findings. International Journal of Listening, 21(2), 140–155. doi:10.1080/10904010701302022) reported better comprehension, memory, and ability to follow directions following use of the Tomatis Method in a group of children who had auditory processing problems.
Mixed results were also demonstrated for use of another auditory program, Auditory Integration Training (AIT: aka the Berard method). Although several studies suggested limited benefits (Edelson et al., 1999Edelson, S. M., Arin, D., Bauman, M., Lukas, S. E., Rudy, J. H., Sholar, M., & Rimland, B. (1999). Auditory integration training: A double-blind study of behavioral and electrophysiological effects in people with autism. Focus on Autism and Other Developmental Disabilities, 14(2), 73–81. doi:10.1177/108835769901400202; Rimland & Edelson, 1994Rimland, B., & Edelson, S. M. (1994). The effects of auditory integration on autism. American Journal of Speech-Language Pathology, 3, 16–24., 1995Rimland, B., & Edelson, S. M. (1995). Brief report: A pilot study of auditory integration training in autism. Journal of Autism and Developmental Disorders, 25(1), 61–70. doi:10.1007/BF02178168), these studies also had important methodological weaknesses. Four well-controlled studies of AIT failed to find any behavioral improvement (Bettison, 1996Bettison, S. (1996). The long-term effects of auditory training on children with autism. Journal of Autism and Developmental Disorders, 26(3), 361–374. doi:10.1007/BF02172480; Gillberg, Johansson, Steffenburg, & Berlin, 1997Gillberg, C., Johansson, M., Steffenburg, S., & Berlin, O. (1997). Auditory integration training in children with autism: Brief report of an open pilot study. Autism, 1(1), 97–100. doi:10.1177/1362361397011009; Mudford et al., 2000Mudford, O. C., Cross, B. A., Breen, S., Cullen, C., Reeves, D., Gould, J., & Douglas, J. (2000). Auditory integration training for children with autism: No behavioral benefits detected. American Journal of Mental Retardation, 105(2), 118–129. doi:10.1352/0895-8017; Zollweg, Palm, & Vance, 1997Zollweg, W., Palm, D., & Vance, V. (1997). The efficacy of auditory integration training: A double blind study. American Journal of Audiology, 6(3), 39.), the most recent of which found no benefit of AIT over a control condition on measures of IQ, of comprehension, or of social adaptive behavior (Mudford et al., 2000Mudford, O. C., Cross, B. A., Breen, S., Cullen, C., Reeves, D., Gould, J., & Douglas, J. (2000). Auditory integration training for children with autism: No behavioral benefits detected. American Journal of Mental Retardation, 105(2), 118–129. doi:10.1352/0895-8017). In a systematic review of six randomized controlled trials, Sinha, Silove, Wheeler, and Williams (2006Sinha, Y., Silove, N., Wheeler, D., & Williams, K. (2006). Auditory integration training and other sound therapies for autism spectrum disorders: A systematic review. Archives of Disease in Childhood, 91(12), 1018–1022. doi:10.1136/adc.2006.094649) concluded that there was not enough evidence to support the use of AIT.
Three studies of auditory intervention programs have been published in the occupational therapy literature. One was a case study (Nwora & Gee, 2009Nwora, A. J., & Gee, B. M. (2009). A case study of a five-year-old child with pervasive developmental disorder-not otherwise specified using sound-based interventions. Occupational Therapy International, 16(1), 25–43. doi:10.1002/oti.263) and the other (Hall & Case-Smith, 2007Hall, L., & Case-Smith, J. (2007). The effect of sound-based intervention on children with sensory processing disorders and visual–motor delays. American Journal of Occupational Therapy, 61(2), 209–215. doi:10.5014/ajot.61.2.209) reported improvement only when the intervention was combined with a sensory diet that was poorly described and not manualized. The third study (Bazyk et al., 2010Bazyk, S., Cimino, J., Hayes, K., Goodman, G., & Farrell, P. (2010). The use of therapeutic listening with preschoolers with developmental disabilities: A look at the outcomes. Journal of Occupational Therapy, Schools, & Early Intervention, 3(2), 124–138. doi:10.1080/19411243.2010.491013), implemented in a preschool setting, found an accelerated rate of development on standardized measures; however, the results were confounded because participants continued to receive routine occupational therapy intervention during the study.
Many of the reported outcomes of auditory programs are hypothesized to be related to changes in arousal linked to activitation of the autonomic nervous system (Sollier, 2005Sollier, P. (2005). Listening for wellness: An introduction to the Tomatis method. Mozart Center Press.). For the purposes of this paper, arousal is defined as “increased neuronal excitability that mobiizes the internal resources needed to maintain alertness” (p. 93). Classic theories of arousal assert that an appropriate level of arousal is necessary to support attention and enhance learning (Fischer, Langner, Birbaumer, & Brocke, 2008Fischer, T., Langner, R., Birbaumer, N., & Brocke, B. (2008). Arousal and attention: Self-chosen stimulation optimizes cortical excitability and minimizes compensatory effort. Journal of Cognitive Neuroscience, 20(8), 1443–1453. doi:10.1162/jocn.2008.20101; Hebb, 1955Hebb, D. O. (1955). Drives and the CNS (conceptual nervous system). Psychological Review, 62(4), 243–254. doi:10.1037/h0041823). Thus, if changes in arousal occur following participation in an auditory program it may be relevant to understanding the underlying mechnaism of change. Drawing on this supposition, several speculations have been made as to the observed changes in arousal being due to (a) the calming effect of listening to music (Alvarsson, Wiens, & Nilsson), (b) the style of music being listened to (Roque et al., 2013Roque, A. L., Valenti, V. E., Guida, H. L., Campos, M. F., Knap, A., Vanderlei, L. C., & De Abreu, L. C. (2013). The effects of different styles of musical auditory stimulation on cardiac autonomic regulation in healthy women. Noise & Health, 15(65), 281–287. doi:10.4103/1463-1741.113527), or (c) the person experiencing pleasure during music listening (Salimpoor, Benovoy, Longo, Cooperstock, & Zatorre, 2009Salimpoor, V. N., Benovoy, M., Longo, G., Cooperstock, J. R., & Zatorre, R. J. (2009). The rewarding aspects of music listening are related to degree of emotional arousal. PloS One, 4(10), e7487. doi:10.1371).
Arousal is frequently studied by measuring electrodermal activity (EDA), a physiologic measure used in the laboratory (Dawson, Schell, & Filion, 2000Dawson, M. E., Schell, A. M., & Filion, D. L. (2000). The electrodermal system. In J. T. Cacioppo, L. G. Tassinary, & G. G.Berntson (Eds.), Handbook of psychophysiology (2nd ed., pp. 200–223). New York, NY: Cambridge University Press.) in children with and without sensory processing challenges (Schoen, Miller, Brett-Green, & Nielsen, 2009Schoen, S. A., Miller, L. J., Brett-Green, B. A., & Nielsen, D. M. (2009). Physiological and behavioral differences in sensory processing: A comparison of children with autism spectrum disorder and sensory processing disorder. Frontiers in Integrative Neuroscience, 3, 29. doi:10.3389/neuro.07.029.2009). Only one previous study has explored changes in arousal following a sensory based intervention. That pilot study of the effectiveness of occupational therapy with children who had sensory processing challenges showed a decrease in electrodermal activity following intervention two times a week for 10 weeks (Miller, Coll, & Schoen, 2007Miller, L. J., Coll, J. R., & Schoen, S. A.(2007). A randomized controlled pilot study of the effectiveness of occupational therapy for children with sensory modulation disorder. American Journal of Occupational Therapy, 61(2), 228–238. doi:10.5014/ajot.61.2.228). What is not known is whether arousal changes with auditory interventions.
Aims of the Study
Thus, the primary aim of this pilot study was to explore the effects of a newly developed auditory program, known as Integrated Listening Systems (iLs). Specifically, the Focus Series sensory motor program (heretofore referred to as the iLs program) combines listening to acoustically processed, low frequency music via air conduction and bone conduction with participation balance, movement, and visual-motor activities. Our research questions were exploratory in nature due to the lack of research using this program—specifically, (1) What individualized family goals are impacted following participation in the iLs program? (2) Does the iLs program produce changes in arousal? (3) Are standardized measures of behavior, emotion, and functional abilities sensitive to change, and (4) What are parents’ qualitative experiences relative to the feasibility and utility of the iLs program?
Materials and Methods
The study received institutional review board approval from Rocky Mountain University of Health Professions and followed all standards set by the board. All participants’ parents provided written consent, and participants above age 7 provided written assent. Following study participation, all families were allowed to keep the iLs system.
This study employed a single-subject, nonconcurrent, multiple-baseline, repeated-measure-across-subjects, AB design in which A represented the baseline phase and B represented the intervention phase with a postintervention no-treatment phase. This design is a useful first step in treatment-effectiveness research seeking to establish a relationship between an individualized intervention and change in targeted outcomes (Bloom, Fischer, & Orme, 2006Bloom, M., Fischer, J., & Orme, J. G.(2006). Evaluating practice (5th ed.). Boston, MA: Pearson.; Kennedy, 2005Kennedy, C. H. (2005). Single-case designs for education research. Boston, MA: Allyn and Bacon.; Kielhofner, 2006Kielhofner, G. (2006). Research in occupational therapy, methods of inquiry for enhancing practice. Philadelphia, PA: F. A. Davis.). The subject serves as his or her own control, with performance of a subject prior to intervention compared to his or her performance during and after intervention. The nonconcurrent design offers greater flexibility in clinical settings because baseline data from the participants does not have to be collected concurrently (i.e., at the same time) (Harvey, May, & Kennedy, 2004Harvey, M. T., May, M. E., & Kennedy, C. H. (2004). Nonconcurrent multiple baseline designs and the evaluation of educational systems. Journal of Behavioral Education, 13(4), 267–276. doi:10.1023/B:JOBE.0000044735.51022.5d; Kennedy, 2005Kennedy, C. H. (2005). Single-case designs for education research. Boston, MA: Allyn and Bacon.). When repeated with multiple subjects, this design provides a cost-effective and systematic method for replication of results (Kennedy, 2005Kennedy, C. H. (2005). Single-case designs for education research. Boston, MA: Allyn and Bacon.).
The repeated measure for this study was individualized behavioral goals. Each participant’s data was collected for approximately 16 weeks. Baseline (A) was the control period. During this phase, the goals were scored by the parent each week, for each participant, over a 3- to 5-week period. The intervention phase (B), consisted of 40 one-hour sessions of the iLs program delivered 5 days a week over an 8-week period, four times at home and once at the clinic. Each week the goals were scored again by the parent. The postintervention phase consisted of 2 to 5 weeks of data collection on individualized goals to evaluate whether gains could be maintained when the intervention was stopped.
Instruments: Assessment Measures
Scale Assessment and Inventory
The Sensory Processing (SP) scale is a comprehensive assessment of Sensory Modulation Disorder. It has two parts: (1) the Inventory, which is an informant-based measure completed by parents/caregivers and (2) the Assessment, which is an examiner-administered performance measure (Schoen, Miller, & Sullivan, 2014Schoen, S. A., Miller, L. J., & Sullivan, J. C.(2014). Measurement in sensory modulation: The sensory processing scale assessment. American Journal of Occupational Therapy, 68(5), 522–530. doi:10.5014/ajot.2014.012377). The SP Scale consists of three subscales: Sensory Over-Responsivity, Sensory Under-Responsivity and Sensory Seeking/Craving. Each subscale provides information about behavioral responses to sensory experiences across seven sensory domains (touch, vision, sound, movement (proprioception, vestibular), taste, and smell). Children and adults from ages 3 to 49 have been tested, with internal reliability > .90 and discriminant validity effect sizes > 1.0 (Schoen, Miller, & Green, 2008Schoen, S. A., Miller, L. J., & Green, K. E.(2008). Pilot study of the sensory over-responsivity scales: Assessment and inventory. American Journal of Occupational Therapy, 62(4), 393–406. doi:10.5014/ajot.62.4.393; Schoen et al., 2014Schoen, S. A., Miller, L. J., & Sullivan, J. C.(2014). Measurement in sensory modulation: The sensory processing scale assessment. American Journal of Occupational Therapy, 68(5), 522–530. doi:10.5014/ajot.2014.012377). Used in combination with parent interview and clinical observation, this scale allows the clinician to characterize an individual’s sensory processing impairments.
Tests for Auditory Processing Disorders in Children—SCAN-3:C
The SCAN-3:C (Keith, 2009Keith, R. W. (2009). SCAN-3:C Test for auditory processing disorders in children. San Antonio, TX: PsychCorp.) is a standardized assessment of auditory processing skills for children between the ages 5.0 to 12.11. The three diagnostic tests, Filtered Words, Competing Words and Competing Sentences were used to characterize the sample and to screen for auditory processing challenges. These tests had high internal reliability and test—retest reliability and therefore were used for this study to screen for auditory processing challenges. Validity data support the use of the SCAN-3:C largely for screening purposes (Keith, 2009Keith, R. W. (2009). SCAN-3:C Test for auditory processing disorders in children. San Antonio, TX: PsychCorp.).
Individualized Goals: Visual Analog Scale
Individualized family goals were constructed for each participant following the parent interview. Each goal was converted into a Visual Analog scale (VAS) by the lead investigator and was stated in a positive direction along a 5-inch horizontal line ranging from 1, indicating that the behavior occurs none of the time, to 5, indicating that the behavior occurs all of the time. For example, Ability to Follow Directions was a goal for six out of seven participants. The VAS was the repeated measure recorded weekly for the entire 16 weeks. VAS has been found to be a reliable and valid measure of a variety of subjective phenomena (Wewers & Lowe, 1990Wewers, M. E., & Lowe, N. K. (1990). A critical review of visual analogue scales in the measurement of clinical phenomena. Research in Nursing & Health, 13(4), 227–236. doi:10.1002/(ISSN)1098-240X) and is one of the most commonly used paradigms in the study of pain (Jensen, Chen, & Brugger, 2003Jensen, M. P., Chen, C., & Brugger, A. M.(2003). Interpretation of visual analog scale ratings and change scores: A reanalysis of two clinical trials of postoperative pain. Journal of Pain, 4(7), 407–414. doi:10.1016/S1526-5900(03)00716-8). The VAS was scored by measuring the distance in inches (to the closest 32nd of an inch) from the beginning end of the scale to the parent’s mark on the line.
Arousal Measures: Sensory Challenge Protocol
The Sensory Challenge Protocol (Miller et al., 1999Miller, L. J., McIntosh, D. N., McGrath, J., Shyu, V., Lampe, M., Taylor, A. K. … Hagerman, R. J. (1999). Electrodermal responses to sensory stimuli in individuals with fragile X syndrome: A preliminary report. American Journal of Medical Genetics, 83(4), 268–279. doi:10.1002/(ISSN)1096-8628) is a well-studied standard psychophysiologic laboratory paradigm that has been in use since 1995 (Hagerman et al., 2002Hagerman, R. J., Miller, L. J., McGrath-Clarke, J., Riley, K., Goldson, E., Harris, S. W. … McIntosh, D. N. (2002). Influence of stimulants on electrodermal studies in fragile X syndrome. Microscopy Research and Technique, 57, 168–173. doi:10.1002/(ISSN)1097-0029; McIntosh, Miller, Shyu, & Hagerman, 1999McIntosh, D. N., Miller, L. J., Shyu, V., & Hagerman, R. (1999). Sensory-modulation disruption, electrodermal responses, and functional behaviors. Developmental Medicine & Child Neurology, 41, 608–615. doi:10.1017/S0012162299001267; Miller, Reisman, McIntosh, & Simon, 2001Miller, L. J., Reisman, J. E., McIntosh, D. N., & Simon, J. (2001). An ecological model of sensory modulation: Performance of children with Fragile X Syndrome, autism, attention-deficit/hyperactivity disorder, and sensory modulation dysfunction. In S. S.Roley, E. I. Blanche, & R. C. Schaaf (Eds.), Understanding the nature of sensory integration with diverse populations (pp. 57–88). San Antonio, TX: Therapy Skill Builders.).
Electrodermal activity is obtained using the palmar electrodes supplied with PSYLAB (Contact Precision Instruments, Cambridge, MA). The PSYLAB software program collects EDA measures of arousal at rest during baseline and recovery when the child sits quietly and no stimuli are presented. Skin conductance level is recorded in microSeimans (μS). During the stimulation phase of the experiment, EDA amplitudes reflective of sensory reactivity are recorded for responses that are > .02 μS and occur between 0.8 and 4.0 seconds after each stimulus.
EDA data is collected continuously in three phases: (1) a 3-minute baseline phase with no stimuli presented; (2) eight trials of sensory stimuli (presented for 3 seconds at a pseudorandom interstimulus interval of 10 or 15 seconds) across six sensory domains—auditory (tone and siren), visual (strobe light), olfactory (wintergreen), tactile (feather), and vestibular (chair tip); and (3) a 3-minute recovery period with no stimuli.
Standardized Measures: Adaptive Behavior Assessment System-II
The Adaptive Behavior Assessment System (ABAS; Harrison & Oakland, 2003Harrison, P. L., & Oakland, T. (2003). Adaptive behavior assessment system (2nd ed.). San Antonio, TX: PsychCorp.)is a norm-referenced report measure designed to assess adaptive behavior in individuals from birth to age 89 years. The scale includes 10 adaptive skill areas from which four composite scores are derived: (1) conceptual composite (e.g., communication, functional academics, and self-direction); (2) social composite (e.g., leisure and social skills); (3) practical composite (e.g., self-care, home living, community use, and health and safety); and (4) general adaptive composite (e.g., the sum of all adaptive skill areas). The parent/primary caregiver form was used in this study and the composite scores and subtest scores were computed to monitor progress over time. Internal reliability is reported to be high for the composite scores, the adaptive domains, and all skill areas (Harrison & Oakland, 2003Harrison, P. L., & Oakland, T. (2003). Adaptive behavior assessment system (2nd ed.). San Antonio, TX: PsychCorp.). Similarly strong evidence of content and concurrent validity is reported (Harrison & Oakland, 2003Harrison, P. L., & Oakland, T. (2003). Adaptive behavior assessment system (2nd ed.). San Antonio, TX: PsychCorp.).
Standardized Measures: Behavior Assessment System for Children-2
The Behavior Assessment System for Children-2 (BASC-2) Reynolds & Kamphaus, 2004Reynolds, C. R., & Kamphaus, R. W.(2004). Behavior assessment system for children (2nd ed.). Circle Pines, MN: AGS.) is a multidimensional/multimethod system for assessing children’s social, emotional, behavioral, and adaptive functioning. The parent rating form was used in this study. It consists of a clinical profile, which has nine scales that are used to compute the three composite scores: externalizing, internalizing, and behavior symptom index. The adaptive profile comprises five scales that make up the adaptive skills composite. Composite scores and subscale scores were used in this study to measure progress. It is reported that composite scores have stronger internal reliability than the individual scales and have strong construct, convergent, and divergent validity (Reynolds & Kamphaus, 2004Reynolds, C. R., & Kamphaus, R. W.(2004). Behavior assessment system for children (2nd ed.). Circle Pines, MN: AGS.).
Seven children and their families participated in this study. The study was conducted at a private clinic in Greenwood Village, CO. Participants were recruited through posted invitation letters from the center. Interested parents signed a form consenting to be contacted. Children were selected if they met inclusion criteria and families were willing to postpone participation in other interventions (e.g., occupational therapy, speech therapy) for the duration of the study. All parents reported that their child had challenges in daily activities at home and school but had not received previous treatment for sensory issues.
Inclusion criteria were: (1) significant sensory processing impairments reported to be interfering with performance at home or school based on parent report on the Sensory Processing Scale Inventory, parent interview, and confirmation by an occupational therapist trained in using the Sensory Processing Scale Assessment and Inventory; (2) between ages 4 and 18; (3) an intelligence level of “within normal limits” as determined by school aptitude tests; (4) parent report of auditory over-responsivity and/or auditory processing problems and normal hearing; and (5) parent/child willingness to commit to the time and scheduling requirements of the study protocol.
Exclusion criteria were the presence of comorbid disorders such as a seizure disorder, bipolar disorder, deafness, physical disabilities (e.g., cerebral palsy), or neurological impairments; participation in other therapies during the time of the study; and an inability to tolerate wearing headphones for the designated 60 minutes required by the study design.
Four males and three females ranging in age from 5 to 12 years participated in the study. All were Caucasian; socioeconomic status was defined by the education level of the mother—all had at least a high school degree). Interpretation of findings by the evaluating occupational therapist confirmed the presence of tactile and auditory over-responsivity as reported by on the SP Scale Inventory and observed on the SP Scale Assessment for all participants. Three participants also had symptoms of sensory craving behavior and one participant had symptoms of sensory under-responsivity based on the above measures. Four out of seven participants had atypical scores on two subtests of the SCAN-3:C (e.g. scores < 1 standard deviation below the mean) suggestive of auditory processing challenges. The other three participants scored within the typical range for auditory processing. No other comorbid diagnoses were reported.
Three stages constituted the study: (1) administration of the pretest measures, (2) baseline and intervention, and (3) return to baseline, post-testing, and follow-up.
Administration of the pretest measures. Participants first completed the Sensory Processing (SP) Scale Assessment and Inventory in order to fully characterize their sensory processing challenges. The SCAN-3:C was also administered to screen for auditory processing difficulties. A parent interview–goal-setting session was conducted in order to establish the individualized goals for the visual analog scale (VAS) that served as the repeated measure. Pretest measures also included all standardized parent report questionnaires and administration of the Sensory Challenge Protocol Laboratory.
Baseline and intervention. The second stage began with a 3- to 5-week baseline phase (A) during which individualized VAS goals were determined (where the iLs program was not used). Goals whose baselines were unstable could not be extended due to restrictions in participant schedules and, therefore, were not included in the study. Next came the intervention phase (B), which consisted of 40 sessions of the iLs program. The program was administered four times a week at home by the parent and once a week at the clinic by the same research assistant (RA; intervention defined later).
Return to baseline. The final phase of the study (A) was a 2- to 4-week–return-to-baseline period of no intervention, post-testing of all standardized parent report questionnaires, and re-administration of the Sensory Challenge Protocol Laboratory. At this time, parent reactions to participation in the study were solicited, including feasibility and utility of the iLs program as well as subjective changes noted in their child not elicited by the individualized goals or report questionnaires.
Description of the Intervention
The intervention consisted of 40 sessions using the iLs Focus Series sensory motor program. The iLs program is a protocol that uses specific classical music selections that are heard each day. The program is loaded onto an Apple iPod and delivered through a miniamplifier with adjustable air- and bone-conduction volume to Sennheiser headphones custom fitted with bone-conduction capability. Specifically, the sensory motor program emphasizes frequencies at 750 Hz and lower. The iLs music is processed such that different frequencies in each selection are enhanced or dampened. An additional process shifts subtle volume changes from the right-ear channel to the left-ear channel. Both of these alterations to the musical selections are designed into the iLs program in a graded fashion, beginning gently and gradually increasing as the program progresses.
Intervention included listening to the preprogrammed music 5 days a week for 60 minutes. Each program had a specific listening schedule accompanied by visual motor activities performed during the first 15 to 20 minutes of each session that were selected from the Playbook manual and user guide. The sets of activities included balance and core, ball and bean bag, and eye-hand coordination games. The rest of each session was spent doing child-selected motor activities; creative and/or relaxing activities such as drawing, painting, puzzles, building with blocks, and playing cards; or just sitting in a comfortable chair.
Intervention sessions were completed by the RA once a week in the clinic and by the parent 4 days a week at home. Training to the RA and parents in the use of the iLs listening components as well as in the selection and administration of Playbook visual-motor activities was provided by the lead investigator. A program tracker was completed for each participant’s clinic sessions and home sessions to ensure compliance with and fidelity to the program. Intervention fidelity was also ensured through weekly meetings of the RA and the lead investigator and of the RA and participants’ parents to discuss intervention administration, manual adherence, and plans for subsequent sessions.
Parents did not pay for the intervention nor were they required to purchase the iLs unit in order to participate in the study.
Preintervention data were collected during the participant’s first visit. Included were the Sensory Challenge Protocol and the caregiver report questionnaires. The visual analog scale (VAS) goals were developed by the lead investigator following the first parent meeting. Baseline data were collected on the VAS goals via parent report once a week over a 3- to 5-week period prior to initiating the intervention. Each week during the participant’s visit to the clinic in the intervention phase, parents returned to the RA the score for each week’s VAS goals (parent’s mark along the 5-inch line). Postintervention data were collected on the VAS goals using the same procedure as during the baseline phase. Participants returned 2 to 4 weeks following intervention to participate in the Sensory Challenge Protocol and for parents to complete the caregiver report measures and provide subjective feedback on the feasibility and utility of the iLs program.
Owing to the small sample size and the variables’ non-normal distribution (Kolmogorov-Smirnov test, p < .1), nonparametric tests were utilized for all statistical analyses described in the next sections (i.e., individualized goals and standardized measures).
VAS goals were converted into numeric scores by measuring the distance in inches (to the closest 32nd of an inch) from the beginning end of the scale to the parent’s mark along the line. Each goal for each participant, from baseline to postintervention, was plotted on a graph.
Several methods of data analysis were used. Data for individualized VAS goals were examined to determine whether a stable or declining pattern was established during baseline. As is recommended in multiple baseline research, only goals that have a baseline period meeting the following criteria should be included in the intervention phase of a study (Engel & Schutt, 2014Engel, R. J., & Schutt, R. K. (2014). Single-subject design. In R. J. Engel & R. K. Schutt (Eds.), Fundamentals of social work research (2nd ed., pp. 146–173). Thousand Oaks, CA: Sage.): (1) performance that has a relatively stable pattern (no improvement) with little variability; (2) a slope less than .1; or (3) a linear downward trend based on a linear regression analysis. Each participant had at least one goal that met these criteria.
Initial investigation of VAS goals was based on visual analysis of the data. VAS goal data were plotted across phases of the study and analyzed in terms of three dimensions recommended by Kennedy (2005Kennedy, C. H. (2005). Single-case designs for education research. Boston, MA: Allyn and Bacon.). The first dimension examined was level, referring to the mean of the data within a condition. The second dimension examined was trend (or slope), which refers to the best-fit straight line for the data within each condition. The descriptors low, medium, and high are assigned to describe the size of the slope. The third dimension examined was variability of the data, which reflects the degree to which the data points deviate from the best-fit straight line. Variability is a qualitative descriptor like trend, which is classified as high, medium, or low (Kennedy, 2005Kennedy, C. H. (2005). Single-case designs for education research. Boston, MA: Allyn and Bacon.). Patterns of goal achievement were similar within each participant; therefore, the data depicted in Figure 1 is the mean goal performance for each participant across phases of the study. To evaluate these changes in parent-prioritized goals, the Wilcoxin matched-pairs–signed-rank test was used to determine whether differences in level and slope of VAS goal scores changes were statistically significant.
Individual mean goal performance across time.
To evaluate physiologic changes, difference scores were computed comparing pre- and postadministration of the Sensory Challenge Protocol. Variables included the average difference in amplitude by sensory domain and the average difference in EDA during baseline and recovery.
To further evaluate parent perceptions of changes over time, the Wilcoxin matched-pairs–signed-rank test was used to evaluate differences on both the BASC and the ABAS, pre- versus postintervention. Analyses were considered exploratory and designed to inform future studies; therefore, no correction for multiple comparisons was made.
Subjective feedback from parents on the feasibility and utility of the iLs program was aggregated and summarized by the first author.