Posted in Assessment, Cognition & Executive Function, Special Populations

Special Populations: Navigating Diagnoses

I think one of the most interesting parts of finally practicing as an SLP will be having the opportunity to work with children who have speech and language concerns as just one part of a broader disorder or disability. Some of the disorders that we learned are commonly co-morbid with developmental language disorder (DLD) include:

Attention Deficit Hyperactivity Disorder (ADHD)
Primary symptoms of ADHD include inattention, hyperactivity, and distractibility.
• Although ADHD and DLD have similar prevalence rates, awareness of ADHD is much greater and only ADHD rates are being tracked in healthcare service data.
• Studies have shown that children with ADHD show increased maze behaviour during conversation.
• Executive function and continuous performance measures do not clearly differentiate DLD from ADHD due to concerns around their validity (i.e., some children with ADHD will not have executive function deficits).
• Informant ratings (i.e., from parents, teachers, etc.) of the child’s attention, impulsivity, and defiance appear to be more useful measures for differentiating ADHD from DLD (especially when language-loaded items are removed from analysis).

Auditory Processing Disorder (APD)
Children with APD tend to have difficulties processing information and speech in noise.
• When differentiating children with APD and DLD, Ferguson et al. (cited below in Additional Resources) found that the following measures did not differentiate the two disorders:
– Structural language
– Social/pragmatic
– Attention ratings (item analysis suggested possible qualitative differences)
– Speech intelligibility in quiet or noise (despite being the most commonly reported symptom of APD)
– Intelligence (verbal or nonverbal)
– Reading
• Thus, Ferguson et al. concluded that the child’s diagnosis of APD or DLD was determined based on the referral route (i.e., referred to an audiologist vs. a speech-language pathologist)

Autism Spectrum Disorder (ASD)
ASD is characterized by impairments in social communication and social reciprocity, and by the presence of restricted interests and repetitive behaviours.
• DLD can occur co-morbidly with ASD, but ASD cannot occur co-morbidly with social communication disorder (SCD).

Social (Pragmatic) Communication Disorder (SCD)
SCD is defined by a primary deficit in the social use of nonverbal and verbal communication.
• Individuals with SCD may be categorized as having difficulty in using language for social purposes, appropriately matching communication to the social context, following rules of the communication context (e.g., turn-taking), understanding non-literal language (e.g., jokes, idioms, metaphors), and integrating language with nonverbal communicative behaviours.
• Sufficient language skills must be developed before higher-order pragmatic deficits can be detected, so a diagnosis of SCD should not be made until children are 4–5 years of age.
• DLD can occur co-morbidly with SCD, but SCD and ASD are mutually exclusive disorders (the presence of one means the other cannot occur co-morbidly).
• SCD may be considered by some as the “middleman” on a continuum between DLD and ASD

This graphic created by Dr. Lisa Archibald demonstrates some of the shared characteristics between DLD and the above-mentioned disorders. Difficulties with pragmatic and social communication skills (i.e., identifying nonverbal communication markers, following conversational rules, etc.) are present in all of the disorders, which I think highlights how a very diverse variety of skills influences an individual’s ability to be socially competent (i.e., executive functions like attention, language, ability to process information, etc.).


For more information, check out these additional resources:
Ferguson, M. A., Hall, R. L., Riley, A., & Moore, D. R. (2011). Communication, listening, cognitive and speech perception skills in children with auditory processing disorder (APD) or specific language impairment (SLI). Journal of Speech, Language, and Hearing Research, 54(1), 211-227.

Redmond, S. M. (2016;2015;). Markers, models, and measurement error: Exploring the links between attention deficits and language impairments. Journal of Speech, Language, and Hearing Research, 59(1), 62.

Swineford, L. B., Thurm, A., Baird, G., Wetherby, A. M., & Swedo, S. (2014). Social (pragmatic) communication disorder: A research review of this new DSM-5 diagnostic category. Journal of Neurodevelopmental Disorders, 6(1), 41.

CanChild’s Autism Classification System of Functioning: Social Communication

The Communication Matrix
• An assessment tool for children who are not speaking or writing to communicate