Motor disorder and anxious and depressive symptomatology: a monozygotic co-twin control approach.
Motor disorder alone raises anxiety and depression risk in kids, but exercise plus peer skills can turn it around.
01Research in Context
What this study did
Researchers studied 8- to young learners identical twins. One twin had motor disorder. The other did not.
They compared anxiety and depression scores between the twins. Same genes. Different motor skills.
This design ruled out genetics. Any mood differences had to come from life experience.
What they found
The twin with motor disorder scored much higher on anxiety and depression scales.
Even with identical DNA, motor problems alone predicted worse mental health.
The risk was real and separate from any other condition.
How this fits with other research
Wagner et al. (2012) adds a clue. They found peer rejection partly explains why motor trouble leads to behavior issues.
Peng et al. (2026) shows exercise can fix motor skills. Their meta-analysis of 24 studies proves big gains are possible.
Together, the three papers tell a story: motor disorder causes emotional pain, peer problems are the bridge, and exercise is a proven fix.
Why it matters
Screen every child with motor delays for anxiety and depression. Ask about friends and bullying. Add peer skills training to your plan. If the child has DCD, start evidence-based exercise programs shown by Peng et al. (2026) to cut motor deficits. You can lower both motor and mood problems at once.
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02At a glance
03Original abstract
The aim of this study was to investigate the relationship between poor motor ability and anxious and depressive symptomatology in child and adolescent monozygotic twins. The co-twin control design was used to explore these mental health issues in MZ twins concordant and discordant for a motor disorder, and controls. This methodology offers the unique opportunity to control for genetic effects and shared environmental influences, and permits the investigation of non-shared environmental influences. The Developmental Coordination Disorder Questionnaire was used to identify 23 sets of twins discordant for a motor disorder, 23 sets concordant for a motor disorder, and 773 sets of twins with no motor disorder from a total sample of 2122 Australian sets of twins. The Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour questionnaire was used to exclude participants with high Attention Deficit Hyperactivity Disorder symptomatology. Anxious and depressive symptomatology were assessed using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) based questionnaires on Generalised Anxiety Disorder and Sad Affect. Results indicated significantly higher levels of anxious and depressive symptomatology in twins with a motor disorder in discordant pairs compared to their co-twins without a motor disorder, and controls. There were significantly higher levels of anxious symptomatology in twins with a motor disorder in discordant sets than in sets of twins concordant for a motor disorder. There were significantly higher levels of anxious symptomatology in concordant twins than in controls. Implications of these findings are discussed with emphasis on understanding and recognising the relationship between a motor disorder and anxious and depressive symptomatology in clinical practice for children and adolescents with these disorders.
Research in developmental disabilities, 2011 · doi:10.1016/j.ridd.2011.01.042