This is a difficult topic—difficult to think about, to read about, and, in many cases, difficult to help our students and clients who have been (or continue to be) victims of maltreatment. But given the horrifying prevalence of childhood abuse and neglect (the Children’s Bureau estimates 683,000 known victims in 2015), the fact is, we are working with these children whether we know it or not. I’m sure the concerned SLP who asked this question isn’t alone in wanting to know more, so she can do her job better. After all...that’s why we’re all here. 

What does the research say about language and trauma?
To get the big picture, let’s turn first to a meta-analysis of 40 years’ worth of work on this question. Sylvestre et al. (2015) found that, across studies, the language skills of children who are abused and/or neglected are delayed compared to their peers. Age also matters: the younger the child, the bigger the impact abuse and neglect have on language. 

Think of what we know about how and when language develops: early in childhood, as a result of lots of language exposure and reciprocal interaction with caregivers. While lack of quality input isn’t the only factor here (more on that in a minute), it’s logical that the more the ideal conditions for development are disrupted by maltreatment, the more language will be delayed. 
 
The delays affect all areas of language—expressive, receptive, syntax, semantics, morphology, and pragmatics—with the possible exception of phonology (see Culp et al, 1991). The size of the reported differences is variable; Sylvestre et al. found, on average, a difference of half a standard deviation on a norm-referenced language measure. If you look just at children under 6 who are involved in the U.S. Child Welfare System, average PLS-3 scores are a full standard deviation below the mean, and a quarter of the kids are more than -2 SD below the mean (Casanueva et al., 2012). So, we see reduced language skills overall, and a disproportionate number of kids with *very* low scores; expressive language also tends to suffer more than receptive.  

It’s tricky to pin down the specific effects of different types of maltreatment, for a couple of reasons—the data that scientists use is not always that detailed, and there’s a lot of overlap between cases of abuse and neglect. When it is possible to separate groups, some scientists (e.g., Fox et al., 1988, Culp et al., 1991, Spratt et al., 2012) have found that neglect (especially severe neglect) has a more detrimental effect on language than abuse alone.
 
As we know, the effects of persistent early language delays can snowball once a child starts elementary school, especially once “learning to read” shifts to “reading to learn.” Hence early intervention, right? There is evidence that early childhood education can improve the language abilities of kids involved in the child welfare system—a modest effect, on average, but solid gains if you look just at neglected children (Merritt & Klein, 2015). Two problems, though. First, abused/neglected children tend to be under-identified and under-served (Casanueva et al., 2012). Second, the pervasive effects of trauma on the developing brain make it harder for some children to benefit from intervention. Early traumatic experiences can make the body’s stress response systems hyper-sensitive, putting kids’ “fight-flight-or-freeze” response on a hair trigger (De Bellis & Zisk, 2014). It’s pretty hard to learn when your body thinks you’re in danger. Early childhood providers may also struggle with “externalizing behavior problems associated with histories of abuse that can make [children] challenging to ‘manage’ in a classroom setting” (Merritt & Klein, 2015).

What’s an SLP to do?
Aside from knowing what kinds of language issues might be associated with a child’s traumatic experiences, it’s important to be familiar with the behavioral profiles these kids can show, as well as strategies YOU can use to work effectively with them. There has been a push in healthcare and educational settings to shift to “trauma-informed” practice, partially driven by the unfortunate necessity of responding to large-scale disasters and acts of violence, but also by the science on the serious and wide-ranging effects of trauma, adverse childhood experiences (ACEs), and toxic stress. This means there is a wealth of information out there, from books to popular TED Talks to free online CEU courses, that you can check out to learn more. The specifics of trauma-informed or trauma-sensitive care and teaching is beyond the scope of this Q&A, but common themes include seeing students as doing the best they can, learning to de-escalate situations and avoid re-traumatizing traumatized children, providing a supportive presence, and helping children feel safe so that they can escape flight-flight-or-freeze mode and be ready to learn. Remember: relationships with caring adults can help protect children from the effects of ongoing stress (NSCDC, 2004). An SLP, who often has kids on his or her caseload for multiple years, is well placed to be one of those people.

As professionals trying to have a positive impact in the lives of traumatized children, there will be times when we feel frustrated, helpless, or even experience secondary traumatic stress. Even when situations are beyond our control, we can still arm ourselves with the facts and advocate for these kids, both individually and at the systems level. You never know when and where you can make a difference.
 
Also, it’s important to mention that we are nearly always mandatory reporters. If you don’t know your workplace’s procedure for reporting suspected child abuse, make a point to find out.  

• Casanueva, C., Wilson, E., Smith, K., Dolan, M., Ringeisen, H., & Horne, B. (2012). NSCAW II Wave 2 Report: Child Well-Being. OPRE Report #2012-38, Washington, DC: Office of Planning, Research and Evaluation, Administration for Children and Families, U.S. Department of Health and Human Services.​
• Culp, R. E., Watkins, R. V., Lawrence, H., Letts, D., Kelly, D. J., & Rice, M. L. (1991). Maltreated children’s language and speech development: abused, neglected, and abused and neglected. First Language, 11(33), 377–389. https://doi.org/10.1177/014272379101103305. 
• De Bellis, M. D., & Zisk, A. (2014). The biological effects of childhood trauma. Child and Adolescent Psychiatric Clinics of North America, 23(2), 185–222, vii. https://doi.org/10.1016/j.chc.2014.01.002.
• Fox, L., Long, S. H., & Langlois, A. (1988). Patterns of language comprehension deficit in abused and neglected children. The Journal of Speech and Hearing Disorders, 53(3), 239–244. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/3398477. 
• Merritt, D. H., & Klein, S. (2015). Do early care and education services improve language development for maltreated children? Evidence from a national child welfare sample. Child Abuse & Neglect, 39, 185–196. https://doi.org/10.1016/j.chiabu.2014.10.011. 
• National Scientific Council on the Developing Child (2004). Young Children Develop in an Environment of Relationships: Working Paper No. 1. Retrieved from www.developingchild.harvard.edu.
• U.S. Department of Health & Human Services, Administration for Children and Families, Administration on Children, Youth and Families, Children’s Bureau. (2017). Child Maltreatment 2015. Available from http://www.acf.hhs.gov/programs/cb/research-data-technology/statistics-research/child-maltreatment. 
• Spratt, E. G., Friedenberg, S. L., Swenson, C. C., Larosa, A., De Bellis, M. D., Macias, M. M., Brady, K. T. (2012). The Effects of Early Neglect on Cognitive, Language, and Behavioral Functioning in Childhood Psychology, 3(2), 175–182. https://doi.org/10.4236/psych.2012.32026.​
• Sylvestre, A., Bussières, È.-L., & Bouchard, C. (2016). Language Problems Among Abused and Neglected Children: A Meta-Analytic Review. Child Maltreatment, 21(1), 47–58. https://doi.org/10.1177/1077559515616703.