A stimulus control analysis of the picture-word problem in children who are mentally retarded: the blocking effect.
Pictures can block new word learning—show the word first, then add the picture.
01Research in Context
What this study did
Eight students with intellectual disability joined a word-learning game.
Each child saw three kinds of flashcards: word-only, picture-plus-word, or picture-first-then-word.
The teacher switched the card types every day so the child never knew which kind was coming next.
The team counted how many trials each child needed to read the word without help.
What they found
Every child learned the word fastest when the picture was gone.
If a child first saw the picture, the picture acted like a roadblock.
The blocking effect was large and showed up on the very first word set.
How this fits with other research
Logan et al. (2000) ran the same test ten years later and got the same result.
Sanders et al. (1989) saw the same picture block one year earlier, but with sound-blending instead of reading.
Kim et al. (2023) moved the story forward. They showed that after you drop the picture, you can also cut the session to twelve trials and still keep the gain.
Why it matters
If you teach sight words, start with text-only cards. Add pictures later as a reward, not during the first lesson. This small switch can save weeks of teaching time and reduce student frustration.
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02At a glance
03Original abstract
Conditioning to one member of a compound stimulus can be blocked by the presence of a second member to which the response was previously conditioned. This account of selective stimulus control can be used to explain the finding that pictures inhibit learning of written words if the relevant pictures and their verbal equivalents have been paired previously. We tested the blocking explanation of the picture-word problem with 8 mentally retarded students. Following baseline, each student was resented daily with four conditions in an alternating treatments design. In Condition A (blocking), a picture was presented alone and then was followed by the presentation of a picture and written word compound stimulus; in Condition B (blocking/control), a word was presented alone; in Condition C(blocking minimized), a word was enhanced in size and presented alone followed by the word and a picture; and, in Condition D (blocking minimized/control), the enhanced word was presented alone. Each stimulus was presented for 15 s. All students had the lowest percentage of words read correctly in the blocking condition, and all improved when blocking was minimized. Six of 8 students reached their highest percentage of words read correctly in the two control conditions when the words were presented as a single stimulus without pictures. These results indicate that pictures inhibit some students' learning of new words; this may be due to the blocking of conditioning to written words by prior conditioning to pictures.
Journal of applied behavior analysis, 1990 · doi:10.1901/jaba.1990.23-525