NOTE: The “Tomatis Method”, as mentioned in some of the research below, refers to a method of auditory stimulation developed by Dr. Alfred Tomatis. DLS founder, and the current iLs trainer, Ron Minson, MD was a close friend and student of Dr. Tomatis; therefore the iLs professional training and clinical studies continue in the same vein as both Tomatis and DLS.
The research listed below is, in some cases, strictly auditory stimulation (e.g. Tomatis Method and Dynamic Listening Systems) and in others a combination of auditory, visual, and motor stimulation (e.g. the Longitudinal Study from U. of New Mexico).

The Effects of The Tomatis Method of Auditory Stimulation on Auditory Processing Disorder: A Summary of Findings
Deborah Ross-Swain Ed.D., CCC Speech-Language Pathologist
The study’s purpose is to determine the efficacy of the Tomatis Method of auditory stimulation as a therapeutic intervention for Auditory Processing Disorders (APD). 41 subjects (18 females, 23 males; 4.3 to 19.8 years old) were evaluated for A.P.D. All subjects demonstrated improvement with skills of immediate auditory memory, auditory sequencing, interpretation of directions, auditory discrimination and auditory cohesion. Results are significant, e.g. an average improvement in overall auditory processing skills of 49.93%

Early Intervention: A Longitudinal Study of Reading and Reading Related Achievement of Students in Kindergarten Through Second Grade Enrolled in the Alpha Program
Prepared by J. Anne Calhoun, Ph. D. Educational Psychology
Department of Language, Literacy, and Sociocultural Studies
College of Education, University of New Mexico 2006

In this study 36 subjects were evaluated before and after a unique combination of interventions, including DLS. Average reading gain for the 36 children over the 3-month intervention was 2 years

Hillside Health Center Ongoing Study, 2006
Data collected by Harry Armytage (Center Director Maxwell Fravall, D.O.)
This data summary covers 4 aspects of auditory performance affected by DLS programs: visual/auditory processing speed, selectivity, auditory digit span, and right-ear dominance. The sample size ranges from 30-46 subjects; results are significant, e.g. average improvement of 78% in auditory processing, and average improvement of 81% in selectivity (phonetic differentiation) after programs lasting 3-5 months

Hope Charter School Case Studies, 2006
Data collected by Bobbi Van Houten, RN, at Hope Charter School, Florida
These 6 case studies from a Florida charter school show pre- and post-DLS program data measuring changes in reading ability. After completing the 4-month DLS program, in combination with a vestibular/visual stimulation program called Learning Breakthrough, the average gain in reading ability was 2.2 years (comparing beginning Lexile Level with Ending Lexile Level).

The students’ reading improvement is also compared to normative growth per grade level using assessments from NWEA MAP (NW Evaluation Association’s Measures of Academic Performance). The average gain was 36 percentile points, e.g. a student ranking in the 40%ile jumped to the 76%ile after the 4-month program

The Efficacy of the Tomatis Method for Children with learning and communication disorders: a meta-analysis.
Gilmore, Tim (1999). Published in the International Listening Journal, 1999.
A meta-analysis is a specific type of research, which examines previously completed research studies. This meta-analysis looks at 5 studies* of Tomatis-based auditory stimulation remediation. The analysis, involving a total of 231 children, concluded that the remediation significantly improves linguistic skills, psychomotor skills, personal and social adjustment skills, auditory skills, and cognitive skills.

Recommended Books
When Listening Comes Alive, by Paul Madaule
Music and Miracles, by Don Campbell
Sound Bodies Through Sound Therapy, by Dorinne S. Davis

Articles
The Listening Cure, by Nicholas Regush, Equinox Magazine, Canada, April/May 1997
Healing With Music, Published in Alternative Medicine Magazine, Issue #25