Behaviour problems associated with lack of speech in people with learning disabilities.

The team pulled a giant government dataset on people with learning disabilities.

They split the group into those who could talk and those who could not.

Then they counted how many behavior problems each group showed.

People without speech had far more behavior problems than people with speech.

The difference was big enough that the authors urged early communication teaching.

Mastrogiuseppe et al. (2015) extends this picture. They saw toddlers with autism already show fewer and poorer gestures, hinting that communication trouble starts even before words fail.

Adams (1980) and Barnes et al. (1990) are direct successors. Both papers ran small teaching studies right after this 1997 warning. They showed nonverbal kids can learn to mand “yes/no” or play ball when you use prompts, praise, and practice across items.

Leon et al. (2010) adds a later tool: functional communication training cut problem behavior in a delayed child by giving quick attention mands. Together these studies form a chain: spot early gap → teach early words → drop later problems.

If your client has no speech, treat problem behavior as a signal, not a sentence. Start simple mands on day one: yes/no cards, picture exchanges, or a single sign. Use the Adams (1980) recipe—model, reinforce, and rotate at least five item sets so the skill travels. Track gestures too; Mastrogiuseppe et al. (2015) shows even pointing can fade fast. Early communication is behavior prevention.