Assessment & Research

Consistent mapping and automatic visual search: comparing persons with and without intellectual disability.

Merrill (2004) · Journal of intellectual disability research : JIDR 2004
★ The Verdict

Consistent rules speed automatic search for neurotypical learners but matter less for learners with ID.

✓ Read this if BCBAs teaching discrimination or community safety to adults or teens with intellectual disability.
✗ Skip if Practitioners focused only on early childhood or severe problem behavior.

01Research in Context

01

What this study did

Merrill (2004) tested how fast people learn to spot a target picture. One group had intellectual disability. One group did not.

Some trials kept the picture-response rule the same every time. Other trials switched the rule. The team timed how long each person needed to find the picture as more dummy pictures were added.

02

What they found

Neurotypical adults got much slower when the rule kept changing. Their search was no longer automatic.

Adults with ID stayed slow no matter what. The changing rule did not hurt them more, because their search was never automatic to start with.

03

How this fits with other research

Earl et al. (2019) moved the same kind of test to a real street. Adults with ID looked at traffic cues only two-thirds as often as controls. Both studies show weaker top-down control of attention in ID.

Cullinan et al. (2001) found poorer transfer and more dual-task interference in ID. Their motor data line up with the weaker inhibition seen here.

Shire et al. (2022) split kids with ID into two groups: some showed normal switch costs, some showed none. This warns us that not every client with ID will show the same pattern Merrill (2004) found.

04

Why it matters

Keep your stimulus-response pairs locked for neurotypical learners if you want fast, effortless performance. For clients with ID, do not assume automaticity will emerge; instead, build extra prompts and practice. Also, probe attention during community tasks like street crossing—add bright, moving cues because passive scanning is weak.

Free CEUs

Want CEUs on This Topic?

The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.

Join Free →
→ Action — try this Monday

Check that each target stimulus has one fixed response in your protocol; if the client has ID, plan extra prompt trials either way.

02At a glance

Intervention
not applicable
Design
quasi experimental
Sample size
32
Population
intellectual disability, neurotypical
Finding
mixed

03Original abstract

BACKGROUND: Merrill et al. (1996) reported that persons with intellectual disability (ID) were slower at learning a visual search task to automaticity relative to persons of the same age without ID. For persons without ID, automaticity develops most rapidly under conditions in which a response is always the same for a particular stimulus. This study was designed to investigate whether persons with and without ID are differentially sensitive to the influence of consistently mapped versus inconsistently mapped stimulus responses. METHODS: The primary manipulation was the consistency between a particular stimulus and the response to that stimulus in a visual search task. Sixteen participants with ID and 16 without ID searched displays of two, three, or four pictured objects to determine if a target was present. For half of the participants, the targets were always targets. For the other half, the targets became nontargets on 25% of the trials. RESULTS: Analyses focused on changes in response times associated with set size. Because automaticity allows for parallel processing, the elimination of significant effects of set size was taken as an index of the development of automaticity. Results indicated that inconsistent mapping significantly slowed the development of automaticity for the participants without ID but not for the participants with ID. DISCUSSION: Results were discussed in terms of the role of inhibition processes in the development of automatic search and detection. The effectiveness of inhibition processes was compromised by the consistency manipulation. The effect of the consistency manipulation was greater for the participants without ID because they were presumed to be using inhibition processes more effectively during practice than did the participants with ID.

Journal of intellectual disability research : JIDR, 2004 · doi:10.1111/j.1365-2788.2004.00594.x