When Persistent Concussion Symptoms in Young Children: What Parents Need to Know
Many parents are told that young kids “bounce back” quickly after a head injury. A large early childhood concussion study shows that is not always true: about 28 percent of children 6 months to 6 years old still have symptoms one month after a concussion, and some continue to struggle for months.
At Los Angeles Neurosciences in the greater Los Angeles area, we see this pattern in infants, toddlers, and preschoolers who still have changes in behavior, mood, sleep, or balance long after the initial injury.
Key facts: Persistent concussion symptoms under age 6
What did the KOALA study find about concussion in young children?
235 children ages 6 months to 6 years with concussion were followed after emergency department visits.
They were compared with 108 children with orthopedic injuries and 75 healthy controls.
At 1 month, 28 percent of children with concussion still had symptoms vs 10 percent of the orthopedic group and 2 percent of healthy children.
In the concussion group, symptoms persisted in 24 percent at 3 months and 16 percent at 12 months.
Higher early symptom scores predicted which children were more likely to still have symptoms at 1 month.
This work comes from the KOALA (Kids’ Outcomes And Long‑term Abilities) study and is one of the first to quantify persistent concussion symptoms in early childhood.
How concussion looks different in infants, toddlers, and preschoolers
Concussion in very young children is not just a smaller version of concussion in teenagers. The KOALA data and expert commentary highlight several age‑specific issues.
Body and brain differences
Young children have a larger head‑to‑body ratio and weaker neck muscles, so the same external force can transmit more acceleration to the brain. Their skulls are thinner and more pliable, with unfused sutures, which can change how energy is absorbed.Different causes of injury
In older children and adolescents, sports are a major cause of concussion. In kids under 6, head injuries more often come from falls or household accidents.Limited ability to self‑report
Infants and toddlers cannot describe “feeling foggy” or “having trouble concentrating.” Many symptoms appear as behavior and mood changes, sleep disruption, or regression in skills, which are easy to miss without structured observation.
Because of these differences, young children are more likely to be labeled with a vague “unspecified head injury” rather than a clear concussion diagnosis, which can delay appropriate follow‑up.
Common signs of persistent concussion in young children
What are symptoms of persistent concussion in children under 6?
Parents may notice:
Unusual clinginess or increased comfort‑seeking
Irritability, frequent meltdowns, or mood swings not typical for the child
Changes in sleep (difficulty falling asleep, frequent waking, or sleeping much more)
Seeming “off,” slowed, withdrawn, or less interested in play
New clumsiness, balance problems, or reluctance to walk or run
Sensitivity to light, noise, or touch
Difficulty focusing on simple tasks or following directions
Regression in previously mastered skills
The KOALA study showed that almost one third of young children remain symptomatic at 1 month after concussion, and a meaningful minority still have symptoms at 3 and 12 months. This directly challenges the idea that “little kids always bounce back quickly.”
The REACTIONS questionnaire: A tool built for early childhood concussion
One of the strengths of the KOALA study is its use of an age‑appropriate symptom tool called the REACTIONS inventory (Report of Early Childhood Traumatic Injury Observations and Symptoms).
Parents completed REACTIONS at 10 days, 1 month, 3 months, and 12 months after injury.
The questionnaire tracks 17 domains, including attention, memory, slowed thinking or movement, headache, nausea, balance, fatigue, sleep, vision, sensitivities, irritability, mood/motivation, anxiety, regression, and comfort‑seeking.
Symptoms are rated as absent, mild, moderate, or severe.
Higher REACTIONS scores early after concussion were associated with a higher likelihood of persistent symptoms at 1 month. For clinicians, this means that structured parent reports can identify children who may benefit from earlier referral to specialized concussion care.
Risk factors that may affect recovery
The KOALA analysis and related concussion literature suggest several factors that may influence how long symptoms last in children under 6:
Higher early symptom burden on tools like REACTIONS
Pre‑injury personal or family history of migraine, ADHD, learning difficulties, or psychiatric disorders
Socioeconomic factors, which have been linked to outcomes in other brain injury populations
A potential (but not yet statistically confirmed) trend toward better outcomes in children who attend daycare, possibly related to routine and activity patterns
Researchers are also exploring objective biomarkers in blood or saliva to predict which children are most likely to have prolonged symptoms and to guide early interventions.
Why guidelines built for older kids are not enough
Most published concussion guidelines and return‑to‑play protocols focus on school‑age children, adolescents, and adults. For children under 6, there is less clear guidance on:
How to diagnose concussion when the child cannot describe symptoms
How long to rest and how to reintroduce activity and stimulation
Which symptoms should trigger more intensive treatment or referral
Emergency physicians have reported uncertainty in diagnosing concussion in very young children and difficulty applying rest and activity recommendations that were designed for older kids. Experts commenting on the KOALA findings emphasize the need to move beyond passive rest toward structured, actively managed recovery plans with frequent follow‑up, lifestyle adjustments, and graded activity.
When parents in Los Angeles should seek a pediatric concussion evaluation
When should I worry about persistent concussion symptoms in my young child?
You should consider an evaluation with a pediatric‑focused neurologist if your child is under 6 and:
Still seems clearly “different” 1–2 weeks after a head injury
Has ongoing irritability, sleep changes, clinginess, or regression in skills
Has balance problems, repeated falls, or new reluctance to walk/run
Still has noticeable symptoms or behavior changes at one month post‑injury
Received a vague diagnosis like “mild head injury” but symptoms are not resolving
Persistent concussion symptoms in early childhood are common—and they respond best to early, structured care.
Parents in Los Angeles, Santa Clarita, and surrounding communities can contact Los Angeles Neurosciences for a focused pediatric concussion evaluation.
How Los Angeles Neurosciences manages concussion in young children
At Los Angeles Neurosciences, our concussion program for children under 6 is built around three principles: early recognition, structured follow‑up, and individualized treatment.
1. Early recognition and diagnosis
Detailed history of the injury, including mechanism (fall, impact, etc.)
Observation‑based symptom assessment guided by age‑appropriate tools like REACTIONS‑style checklists
Careful neurologic and vestibular examination tailored to infants, toddlers, and preschoolers
2. Proactive, individualized management
Rather than relying on generic “rest and wait” advice, we:
Help families adjust routines, sleep, screen time, and activity levels in a graded way
Coordinate physical, vestibular, or vision therapy when indicated
Address headache, sleep, and mood symptoms with appropriate strategies or medications when needed
3. Structured follow‑up and education
Because up to 28 percent of young children still have symptoms at one month, we:
Schedule follow‑up visits to reassess symptoms and function
Provide clear return‑to‑play and return‑to‑learn guidance appropriate for early childhood
Educate parents, pediatricians, and schools about warning signs and realistic recovery timelines
Serving families across Los Angeles and Santa Clarita
Los Angeles Neurosciences provides pediatric concussion care for families in:
Los Angeles
Santa Clarita
San Fernando Valley
Surrounding Southern California communities
If your infant, toddler, or preschooler is experiencing ongoing symptoms after a head injury, our neurology team can help determine whether a concussion is present, how severe symptoms are, and what steps will best support recovery.
To schedule an appointment, call our office or use our online contact form. Early, specialized care gives young children the best chance to return to their usual behavior, sleep, and play as safely and quickly as possible.