A collaborative approach between speech-language pathologists (SLPs) and occupational therapists (OTs) is a highly effective treatment strategy, as the combination of the two therapeutic approaches allows therapists to address most of the core deficits and differences attributed to autism spectrum disorder (ASD). Language, communication, and social skills difficulties are one of the major core deficits listed in the diagnostic criteria of ASD (American Psychiatric Association 2013). Additional diagnostic criteria include sensory integration or processing differences, and sensory modulation differences, including hyper- and hypo-reactivity to sensory input. Individuals with these differences struggle to make sense of a world they cannot predict, organize, or respond to effectively.

The theory behind sensory integration is that it is the basis for all human behavior. As Dr. Ayres (1995) shared, sensory integration is “the process of organizing sensory inputs so that the brain produces a useful body response and also useful perceptions, emotions, and thoughts. Sensory integration sorts, orders, and eventually puts all of the individual sensory inputs together into a whole brain function. When the functions of the brain are whole and balanced, body movements are highly adaptive, learning is easy, and good behavior is a natural outcome.”

Thus, if sensory input is not integrated purposefully and usefully, an individual is not able to respond consistently and in an adaptive way. This relates to the ability for a child to communicate successfully using verbal, nonverbal, and contextual information. An individual that cannot integrate sights, sounds, and other sensory inputs that compete with sight and sound is not able to respond to those inputs and produce an adaptive response, which would be the basis of communication.

Instead, individuals who do not take in or respond to sensory input adequately develop sensory sensitivities or sensory-seeking behaviors, stereotypical behaviors and vocalizations, abnormal body movements or awareness, and/or atypical speech sounds and patterns.

In order to treat these differences, OTs and SLPs may find effective treatment lies in integrating sensory inputs into communication and evidence-based strategies, to allow the individual to maintain arousal, sustain optimal attention, react with expected emotions and affect, and engage purposefully in action as a response (Anzalone and Williamson 2001). These four A’s are core to sensory integration theory regarding modulation (arousal, attention, affect, and action). Without these, successful interventions are very difficult to achieve.

Evaluation of oral-motor skills is often times overlooked when evaluating the treatment needs of students with ASD. Often times, programs that are trying to encourage verbal language development have not focused on the child’s ability to process sensory information. The result is a system that cannot produce the movements needed for verbal imitation or to even produce a sound or a syllable. For example, if a child is hypersensitive to any tactile input in their mouth, they will not be able to produce a /d/ or /t/ sound that requires the tongue to make contact with the palate. Children with ASD are often unable to register and modulate sensory information in one or more of the sensory systems (Ayres 1979; Flanagan 2008). Not being able to register and modulate sensory information interferes with the development of oral-motor skills which in turn interferes with feeding skills, speech production, and communication.

Speech is considered to be vocal communication and is comprised of the sounds of language. Prior to the development of speech, communication begins at birth. Infants learn to communicate using their senses. They communicate through what they hear, see, touch, and feel, through their movement and interactions in their world.

Research has confirmed that infants show preferences for human faces over other stimuli, speech over other sounds within the environment, female voices over other voices, and the sound of their own mother’s voice over other female’s voices. They are able to use their sensory systems to facilitate and attend to what is most relevant and to inhibit, or ignore that which is less relevant. To communicate effectively, individuals must be able to exchange information.

Communication deficits are central to the diagnosis of ASD. However, the deficits are not only in language. The deficits exist more fundamentally in communication regardless of modality. A minority, approximately 20–30 % of children with ASD, do not develop spoken language as a primary means of communication. They also do not compensate for a lack of speech with gestures or other means of communication. Some individuals on the spectrum may be able to repeat sounds and speech, often referred to as echolalia, but may not be able to produce spontaneous and meaningful speech needed for communication. Other individuals are able to communicate, but need to be taught to use augmentative and alternative modes of communication to compensate for a lack of recognizable speech sounds. Often times, individuals will resort to the use of behaviors as communicative attempts.

Due to the integration of sensory and motor abilities into the development of speech and language skills, a natural connection between the occupational therapists and SLPs exists. SLPs and OTs have a common foundation of practice. Both disciplines are trained in allied health and medical health fields and share many prerequisite and core coursework. Both professions target daily functions and are trained in understanding anatomy, physiology, neurology, illnesses/disease processes, and medical management of disorders, in order to treat holistically. OT practice often prioritizes self-care, work, play, psychosocial function, motor skills, sensory integration, and related functional issues that impact participation in daily activities. SLPs prioritize functions of speech, communication, cognitive ability, and oral-motor skills that allow individuals to participate in daily activities.

The foundational connection between the two disciplines is the impact of the sensory and motor systems on daily life. If an individual cannot integrate sensory information within their environment, he/she will have difficulty with producing effective communication, speech, or motor response within that environment.

Both disciplines attempt to identify the etiology of presenting issues and diagnoses, and existing skill deficits or difficulties, and then use the process of task analysis to develop an effective treatment plan or therapeutic approach. Both professions are committed to facilitating the development of an individual’s maximal functional potential to achieve independence and success in the skills required for daily life, such as self-care, mobility, and communication.