Infants Experience Sensations of Pain Well Before Their Ability to Comprehend Them
The brain of a newborn processes pain differently from adults due to the distinct rates at which neural networks responsible for various aspects of pain develop, according to a new study from University College London.
In newborns, especially premature infants, the network that processes pain is underdeveloped, meaning their experience of pain is not the same as in adults. This underdevelopment results in limited emotional and cognitive processing of pain compared to older children and adults.
The study, published in the journal PAIN, reveals that the brain's pain processing can be divided into three components:
1. **Sensory-discriminative**: This network identifies and localizes pain intensity and quality. It is present early but still immature in newborns.
2. **Affective-motivational**: This network governs the emotional response to pain. It is developing postnatally.
3. **Cognitive-evaluative**: This network involves appraisal and interpretation of pain, including conscious understanding. It is not fully developed until after birth.
The sensory-discriminative network is functional earlier than the affective and cognitive networks. However, the full conscious awareness and sophisticated emotional processing of pain develop later in infancy. This means newborns feel pain, but their ability to understand and emotionally respond to it is limited compared to older children and adults.
Additional research indicates that the neurobiological mechanisms involved in pain evolve throughout development, with plasticity and different processing strategies at each stage. The newborn brain's pain pathways are more sensitive and immature, making even minor stimuli potentially distressing for premature infants who may react to mild stimuli that adults would barely notice.
The study analyzed brain scans from over 370 infants, some premature and others full-term. The results show that premature babies can feel pain before they can understand or interpret it. Caregivers often rely on behavioral cues to gauge an infant's pain, but this study suggests that even silent infants may be undergoing significant neural stress when exposed to pain.
As infants grow, their pain networks gradually mature, with emotional responses to pain increasing over subsequent months. The cognitive-evaluative network, which helps a person interpret pain, assign meaning, anticipate outcomes, and form memories, does not fully mature until after birth, around or beyond 42 weeks.
In summary, newborns process pain primarily at a sensory level, with fuller emotional and cognitive pain processing maturing over subsequent months after birth. This developmental trajectory explains why infants exhibit pain responses but do not yet interpret or emotionally contextualize pain as older children and adults do.
References: - The findings are based on recent studies published in 2025 by University College London and other research institutions exploring infant pain processing and brain development. - Infants can form implicit memories of early painful experiences even if they cannot consciously recall them. - The first pain-processing network to mature is the sensory-discriminative network, responsible for detecting and localizing pain, which becomes functional around 34 to 36 weeks after conception. - Emotional and cognitive networks in infants lag behind those in adults, with some connections involving the prefrontal cortex missing or weaker than those in adults. - The cognitive-evaluative network, which helps a person interpret pain, assign meaning, anticipate outcomes, and form memories, does not fully mature until after birth, around or beyond 42 weeks.
- The study from University College London reveals that newborns have a distinct processing system for pain due to the underdeveloped nature of the sensory-discriminative network, a component of pain processing in the brain.
- While the sensory-discriminative network is present in newborns, it’s still immature, indicating that newborns feel pain but may not fully understand or emotionally respond to it as adults do.
- As a result of this developmental imbalance, infants may show pain responses but lack the ability to interpret or emotionally contextualize pain as older children and adults do.
- The findings also suggest that even silent infants may experience significant neural stress when exposed to pain, making it crucial for caregivers to rely on behavioral cues to gauge an infant's pain levels.
- Further research in the field of health and wellness, neurological disorders, and medicine will help us better understand the evolution of pain processing throughout childhood and its impact on medical-conditions, science, and the future.
