How to Tell if a Baby Has Brain Damage

Brain damage in a baby can show up as early as the first minutes of life or not become apparent until months or even years later, depending on where the injury occurred and how severe it is. Some signs are dramatic and obvious, like seizures in the delivery room. Others are subtle enough that only a trained observer or a parent who knows what to watch for will catch them. There is no single test that catches every case, and the picture is complicated by the fact that a developing brain changes so rapidly that what looks normal at two months might look clearly abnormal by ten months.

What Happens in the First Minutes

The first formal assessment of a newborn’s brain function happens almost immediately. The Apgar score, recorded at one minute and five minutes after birth, grades a baby on heart rate, breathing effort, muscle tone, reflexes, and skin color. Low scores at five minutes are consistently linked to a greater risk of later neurological problems, and scores that remain low at ten minutes carry even higher risk.¹ A large Swedish study found that the risk of cerebral palsy climbed steeply as five-minute Apgar scores dropped, and a ten-minute score of 3 was associated with a dramatically elevated risk compared to a perfect score of 10.²

That said, a low Apgar score alone does not mean a baby has brain damage. Most babies who have briefly low scores recover without any lasting problems. Even among babies whose scores remain low at both one and five minutes, roughly nine out of ten show no neurological impairment on later follow-up.³ What the score does is flag a baby who needs closer monitoring. It is a starting signal, not a verdict.

Seizures and Other Physical Signs in the First Days

Seizures are one of the most important signs of brain injury in a newborn. They often reflect acute damage from oxygen deprivation, stroke, or bleeding inside the skull.⁴ Neonatal seizures look different from seizures in older children. You might see rhythmic jerking of one limb, lip smacking, unusual eye movements, or episodes where the baby suddenly goes rigid or limp. Some seizures in newborns are so subtle they can only be detected by an electroencephalogram (EEG), not by watching the baby.

When doctors suspect brain injury, particularly after a difficult delivery involving oxygen deprivation, they assess the baby using a clinical staging system. This involves checking the baby’s level of consciousness, muscle tone, reflexes like sucking and the startle response, pupil size, heart rate, breathing patterns, and gut function. Together these paint a picture of how severely the brain is affected and which areas may be involved.⁵

Difficulty sucking and swallowing is another early physical red flag. A systematic review found that sucking and swallowing problems in the first days of life predicted later neurodevelopmental outcomes in the majority of studies examined.⁶ A baby who cannot coordinate sucking, swallowing, and breathing well enough to feed may have damage to the brainstem or other areas that control these basic motor patterns. Not every baby who struggles to latch has brain damage, of course. Prematurity, tongue-tie, and other factors cause feeding trouble too. But when feeding difficulty appears alongside other concerning signs, it adds to the picture.

Abnormal Reflexes and Muscle Tone

Healthy newborns come equipped with a set of primitive reflexes: the startle (Moro) reflex, the grasp reflex, the rooting reflex, and others. These reflexes are present at birth, follow a predictable pattern, and gradually disappear as the brain matures over the first year. When they are absent, weak, exaggerated, or asymmetric, it can point to brain injury. Multiple studies have demonstrated that the pattern of these reflexes can help clinicians make early, tentative diagnoses of cerebral palsy and other neurological conditions within the first year of life.⁷ ⁸

Muscle tone is closely related and equally telling. A baby with brain damage may feel unusually floppy (hypotonic) or unusually stiff (hypertonic). Some babies alternate between the two. Hypotonia in the early weeks can sometimes shift to hypertonia as the months go on, a pattern that often points toward cerebral palsy. Tone that is clearly different on one side of the body is particularly concerning, because it suggests damage to one hemisphere of the brain. If a baby consistently keeps one fist clenched while the other hand is relaxed, or strongly prefers one hand before twelve months of age, that asymmetry is worth investigating.

Head Size Changes

Pediatricians track head circumference at every well-child visit for good reason. A head that grows too quickly can signal fluid buildup inside the skull (hydrocephalus), while a head that grows too slowly can suggest the brain itself is not developing as expected. In a study of infants with abnormally rapid head growth, about a third of cases turned out to be hydrocephalus, while the majority were benign familial large heads with no neurological significance.⁹ This illustrates a recurring theme: any single sign in isolation can have innocent explanations. What matters is how multiple signs fit together and whether the trajectory over time is concerning.

A bulging soft spot (fontanelle), prominent veins on the scalp, or a “sunset” appearance to the eyes where the iris seems pushed down can all accompany increased pressure inside the skull. These signs warrant urgent medical evaluation.

When Developmental Milestones Are Late or Missing

Some forms of brain damage are not obvious at birth. Milder injuries, or injuries to parts of the brain that handle higher functions like language, problem-solving, and social behavior, may not become apparent until a baby fails to meet developmental milestones. Rolling over, sitting up, babbling, reaching for objects, and making eye contact all follow a rough timeline in typical development. Persistent delays across several of these areas raise concern.

Research on infants with traumatic brain injury found that those injured in infancy showed worse trajectories in communication, gross motor skills, problem-solving, and social-emotional development compared to children with non-brain injuries, and that babies injured at younger ages fared worse than toddlers injured later.¹⁰ Even more troubling, some deficits only become visible as a child gets older and faces more complex cognitive demands. Problems with attention, memory, and specific learning abilities may not surface until school age, and behavioral problems stemming from frontal lobe injury can continue to emerge well into adolescence.¹¹

This delayed emergence of problems is one of the most unsettling aspects of infant brain injury for families. A baby who seems to be developing well at six months may struggle to keep up by age three. Extended follow-up, often well beyond the toddler years, is necessary to get the full picture.

Vision and Sensory Clues

Brain damage can affect a baby’s vision even when the eyes themselves are perfectly healthy. This is known as cerebral visual impairment, where the problem lies in the brain’s ability to process what the eyes see rather than the eyes’ ability to capture light. It is one of the leading causes of visual problems in children in developed countries, and its severity depends on the location and extent of the brain damage.¹²

In premature infants who develop white matter injury, a high rate of visual impairment has been documented, typically involving poor visual acuity, eye movement problems, and reduced peripheral vision. MRI findings showing damage to the visual pathways running through the white matter correlated with how bad the visual outcome was.¹³ Different locations of brain injury produce different visual profiles, so the pattern of visual difficulty itself can sometimes help doctors figure out what part of the brain was affected.¹⁴

What parents might notice is a baby who does not seem to fixate on faces, does not track a moving toy, or seems to look “through” things rather than at them. Some babies with cerebral visual impairment see better in their peripheral vision and may appear to look sideways at objects rather than straight on. Hearing problems can also accompany brain injury, so failing to startle at loud sounds or not turning toward a parent’s voice can be relevant signs as well.

Diagnostic Imaging and Monitoring

When clinical signs suggest brain injury, doctors turn to imaging. Cranial ultrasound is usually the first step for newborns, because it can be done at the bedside without sedation by using the soft spot on the baby’s skull as a window. It reliably identifies severe abnormalities like large bleeds or major structural damage. Research comparing cranial ultrasound with MRI found that ultrasound can detect the severe brain abnormalities that MRI would show and can predict abnormal development at both one and three years of age. MRI picks up subtler abnormalities that ultrasound misses, but those subtler findings, by themselves, do not predict developmental problems as strongly.¹⁵ For most brain structures, ultrasound measurements closely match MRI measurements, though a few structures show small but meaningful differences.¹⁶

For detecting seizures, continuous EEG monitoring is the gold standard. Many neonatal intensive care units also use amplitude-integrated EEG (aEEG), a simplified version that compresses the brain’s electrical signal into a trend line that nurses and doctors can monitor around the clock. This is useful for quickly evaluating brain function after oxygen deprivation and for spotting seizures.¹⁷ The aEEG reliably catches major seizure episodes on its own, but briefer or more focal seizures can be missed unless a full EEG recording runs alongside it.¹⁸

Researchers are also working on blood-based biomarkers that could one day help diagnose brain injury from a simple blood draw. Proteins released when brain cells are damaged, along with markers of heart stress and oxygen deprivation, are being studied for their ability to predict which babies will have lasting problems. Some newer candidates include proteins like neurofilament light and Tau, which are markers of nerve fiber damage. So far, different biomarkers seem better at predicting short-term hospital outcomes than long-term neurological deficits, and no single blood test is yet reliable enough to replace imaging and clinical assessment.¹⁹

The General Movements Assessment

One of the more promising tools for early detection involves simply watching how a baby moves. The General Movements Assessment is a method where a trained observer watches a video of a baby’s spontaneous movements during the first few months of life. Healthy babies display characteristic “fidgety movements,” small, elegant, continuous movements of the neck, trunk, and limbs that appear between about nine and twenty weeks of age. When these fidgety movements are absent, the risk of cerebral palsy goes up substantially.

A prospective study of high-risk infants found that combining absent fidgety movements with abnormal brain imaging gave the highest diagnostic accuracy at over 95%. Used alone, the absence of fidgety movements had high specificity (correctly identifying babies who were fine) and very high negative predictive value, meaning a baby who did show normal fidgety movements was very unlikely to develop cerebral palsy.²⁰ The practical upside for parents is reassurance: if a baby’s spontaneous movements look normal, that is a strong sign the brain is developing well.

Why Premature Babies Need Extra Watching

Premature infants face a higher risk of brain injury than babies born at term, largely because certain brain structures are still in active development during the last trimester. Two common types of injury in preemies are intraventricular hemorrhage (bleeding into the fluid-filled spaces of the brain) and periventricular leukomalacia (damage to the white matter surrounding those spaces). Both are associated with increased risk of cerebral palsy and other developmental problems.²¹

The pattern of brain injury and its consequences differ between premature and full-term infants. In a cohort study comparing the two groups, preterm babies with white matter damage were more likely to develop cerebral palsy, while full-term babies with similar-looking damage had higher rates of intellectual disability and epilepsy.²² This means the same label of “brain injury” can look quite different depending on when in development it occurred. For parents of preemies, routine cranial ultrasounds during the NICU stay and structured follow-up after discharge are the standard approach for catching problems early.

What Can Look Like Brain Damage but Is Not

One of the real pitfalls in evaluating babies for brain damage is that several genetic and metabolic conditions can produce symptoms that look very similar, particularly in the early months. A baby with spasticity, abnormal movements, or delayed development might initially be thought to have cerebral palsy when the actual cause is a treatable metabolic disorder. In populations with high rates of consanguinity, this overlap is especially common, but it happens everywhere.²³

Some inborn metabolic errors can present in the newborn period with symptoms that closely resemble oxygen deprivation injury, including seizures, poor tone, and multi-organ problems. Standard newborn screening catches many metabolic conditions, but not all of the ones that mimic brain injury. When something does not add up, such as a baby with encephalopathy but no known birth complications, or a child with progressive deterioration instead of the stable pattern typical of cerebral palsy, specialized blood, urine, or spinal fluid testing may be needed to find the real cause.²⁴ Getting the correct diagnosis matters because some of these metabolic conditions have specific treatments that can change the outcome entirely.

What Parents Can Do

Parents spend far more time with their baby than any doctor does, and that makes their observations valuable. Structured parent-report tools have been developed to harness this. One such tool, designed to detect cognitive delay in infancy, showed high sensitivity, correctly identifying developmental delay in nearly all affected children, with a strong negative predictive value meaning parents whose babies scored normally could be confident the result was accurate.²⁵ The specificity was lower, meaning some babies flagged as concerning turned out to be fine. But in screening for brain injury, catching affected children and tolerating some false alarms is preferable to missing them.

Beyond formal tools, parents should trust their instincts when something feels off. A baby who is unusually quiet or irritable, who does not seem comforted by being held, who stiffens rather than molds to your body, who does not seem to see you or hear you, or who consistently fails to do what other babies the same age are doing deserves a closer look. Pediatricians hear “something just isn’t right” from parents regularly, and a good clinician takes that seriously.

Therapeutic Cooling and Why Timing Matters

When brain damage is suspected after a difficult birth involving oxygen deprivation, one intervention can improve outcomes if started quickly enough: therapeutic hypothermia, or cooling. The baby’s body temperature is lowered by a few degrees for about 72 hours, which slows the cascade of damage that continues after the initial insult. A randomized controlled trial found that whole-body cooling reduced the risk of death or major disability by about 15 percentage points, meaning that treating roughly seven babies prevented one death or serious disability.²⁶ Earlier research using selective head cooling also showed benefits, though the effect varied depending on how severe the encephalopathy was at the start.²⁷

The critical point is that cooling must begin within six hours of birth. After that window, the treatment becomes less effective. This is one of the reasons why recognizing the early signs of brain injury quickly is so important. The clinical staging described earlier, along with aEEG monitoring, helps doctors decide within the first hours whether a baby qualifies for cooling.

The Developing Brain’s Capacity to Recover

The infant brain has remarkable plasticity. When one area is damaged, nearby or even distant regions can sometimes take over functions that would normally have been handled by the injured tissue. This reorganization happens most vigorously in early life and forms the rationale for early intervention programs like physical therapy, occupational therapy, and speech therapy.²⁸ Clinical examples of this adaptive capacity include how the brain remaps motor control after injury, allowing a child with damage to one hemisphere to regain use of the affected hand through targeted therapy.²⁹

Plasticity is not a guarantee, and it does not mean every injury can be compensated for. Severe or widespread damage may exceed the brain’s capacity to reorganize. But the window of opportunity is real, and it is widest in the first years of life. Identifying brain injury early and starting appropriate therapies as soon as possible gives the brain the best chance to work around the damage. For families, this is the most actionable part of the whole picture: early recognition leads to earlier therapy, and earlier therapy is associated with better outcomes.