Motor and language abilities from early to late toddlerhood: using formalized assessments to capture continuity and discontinuity in development.
Expect toddler skills to seesaw—dips in one area often pair with jumps elsewhere and don’t predict doom.
01Research in Context
What this study did
Ayelet et al. (2014) followed a mixed group of toddlers through regular clinic visits. They gave the same motor and language tests every few months from age one to three.
The team wanted to see if gains and losses line up across the two skill areas. No extra teaching was provided; they just watched natural growth.
What they found
Kids often dipped in one area while rising in the other. A child might crawl better but use fewer words for a month, then flip the pattern the next visit.
These seesaw changes were typical. They did not predict later diagnosis any better than chance.
How this fits with other research
Payne et al. (2020) later showed that one in three autistic preschoolers already scores low on the Vineland motor domain. Their big sample adds weight to the idea that motor lag is common, yet most clinic reports still miss it.
Thomas et al. (2021) went further: in a large survey, motor coordination risk worsened both social and repetitive symptoms in ASD. This supports Ayelet’s picture that motor and other domains are tightly linked.
Paul et al. (2014) captured a similar seesaw, but in adaptive skills. Toddlers with ASD already lagged behind matched DD peers in daily living and receptive language. Together these papers say uneven growth is the rule, not the exception, across diagnoses.
Why it matters
When a two-year-old suddenly stops babbling but climbs higher, relax. Note the change, keep tracking, but don’t rush to re-label. Use tools like the Vineland motor scale at intake; Payne et al. (2020) proved it catches problems clinicians often overlook. Plan goals that boost both motor and language together—because when one dips, the other may soon rise.
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02At a glance
03Original abstract
Developmental tests reflect the premise that decreases in skills over time should be a sign of atypical development. In contrast, from a psychological perspective, discontinuity may be viewed as a normal part of typical development. This study sought to describe the variability in patterns of continuity and discontinuity in developmental scores over time. Seventy-six toddlers (55% boys) from a larger screening study were evaluated at 13 and 30 months using the Mullen Scales of Early Development (MSEL) in five areas: gross motor, fine motor, visual perception, receptive language, and expressive language. Parents completed the First Year Inventory (FYI) at 12 months as well. At 30 months, 23.68% of the sample received a clinical diagnosis (e.g., developmental delay, autism spectrum disorder [ASD]). Toddlers were classified as stable, increasing, or decreasing by at least 1.5 standard deviations (SD) on their scores in each of the five MSEL areas from 13 to 30 months. Between 3.9% and 51.3% of the sample was classified as increasing and 0-23.7% as decreasing across areas. Decreases in motor areas were associated with increases in language areas. None of the toddlers showed decreases greater than 1.5 SD on their MSEL composite scores. There was no single pattern that characterized a certain diagnosis. Higher FYI sensory-regulatory risk was associated with decreases in gross motor. Lower FYI risk was linked with increases in receptive language. Developmental discontinuity in specific developmental areas was the rule rather than the exception. Interpretations of decreases in developmental levels must consider concurrent increases in skill during this emerging period.
Research in developmental disabilities, 2014 · doi:10.1016/j.ridd.2014.03.036