Motor difficulties in young people who offend.
Teen offenders with poorer hand skills and baby reflexes report more aggression, so quick motor checks can sharpen your risk plan.
01Research in Context
What this study did
McPhillips et al. (2021) visited a youth detention center. They tested teen boys on balance, dexterity, and reflex tasks. Staff also rated each boy’s aggression.
The team wanted to know if poor motor skills and lingering baby reflexes go hand-in-hand with fighting or rule-breaking.
What they found
The boys who scored lowest on manual dexterity and still had baby reflexes said they were more aggressive. Balance problems were common but did not predict aggression as strongly.
In short, shaky hands and stuck reflexes flagged higher self-reported anger and violence.
How this fits with other research
Gentry et al. (1980) saw the same motor and reflex gaps in boys with learning disabilities forty years earlier. Martin’s work extends that link to incarcerated teens and shows it predicts aggression, not just school problems.
Little et al. (2015) found weak grip strength tied to worse autism symptoms. Martin swaps grip for dexterity and autism symptoms for aggression, pointing to a broader rule: poor fine motor control echoes across behavior diagnoses.
Chen et al. (2017) links preschool aggression to sleep and ADHD issues. Martin keeps the aggression focus but shifts the risk factor to motor reflexes, suggesting different ages may need different screens.
Why it matters
You now have a five-minute motor screen that costs nothing. Check dexterity and retained reflexes during intake. If scores are low, add motor goals or refer to OT. Tackling these basics may cut future incidents and gives you data to share with courts and families.
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02At a glance
03Original abstract
BACKGROUND: Research suggests that motor difficulties may be closely associated with severe emotional and behavioural problems in children. However, there is limited research on the role of motor function in young adults who offend. AIMS: To assess motor skills, balance, and primary reflex persistence in young people who offend, and to examine the relative association of different motor factors with self-reported levels of aggression. METHODS: We recruited three groups of males (14-18 years); young people serving custodial sentences (n = 33) in a youth justice centre, and an IQ-matched comparison group (n = 36) and an average-IQ comparison group (n = 38) of non-offenders. All completed a standardised test of motor skills, clinical assessment protocols for balance and primary reflex persistence, and a standardised self-report behavioural rating scale. RESULTS: The youth justice group showed significantly lower abilities in some motor skills and balance and significantly higher levels of primary reflex persistence and aggression than both comparison groups. In a multiple regression model, only manual dexterity (p = .032) and primary reflex persistence (p = .002) were significant predictors of aggression. CONCLUSIONS: A broad range of motor difficulties are likely to occur in young people who offend. We discuss the implications of motor difficulties for approaches to rehabilitation of persistent offenders.
Research in developmental disabilities, 2021 · doi:10.1016/j.ridd.2021.104062