Babies born prematurely often face up to months in the NICU. There, they undergo painful inflammatory procedures every day. Even though it’s been established the pain and stress circuitry in the brain is developed in infants, it’s been found that up to 65% of these babies often go through the procedures without analgesia. Some of the procedures include things like inserting feeding tubes and intravenous lines as well as incubation and even repeated heel lancing.

Research now suggests that these painful acts can have a lasting effect on infants into their adulthood. Later in life, infants that have undergone these painful treatments often experienced a dampened awareness of pain and stress as adults. Though some might argue that dampened awareness could be beneficial, a lack of responsiveness to stress and pain can have dire consequences. For example, if older children and adults aren’t able to fully respond to pain, they can sustain potentially dangerous injuries without trying to seek out medical help, or they may wait too long to seek out help and cause lasting damage. In the U.S. alone, it’s estimated that 12% of all infants are considered premature and they stay in the hospital for an average of 25 days, though they can sometimes stay much longer depending on how prematurely they were born.

Georgia State tried to replicate these procedures on male and female pup rats. They performed a single inflammatory procedure on the rates and then later recorded any alterations in specific brain receptors that affect behavioral sensitivity to things like anxiety, pain, and stress in adulthood. The data collected from the research shows that the painful procedure created site-specific changes in the rat’s brain that control how they responded to stressful situations. These areas of the brain are also linked with mood disorders.

These finding mirror the results that are now being reported clinically on infants that experienced unresolved pain following birth. Lead author of the study, Dr. Anne Murphy, associate director of the Neuroscience Institute at Georgia State University says that "while a dampened response to painful and stressful situations may seem advantageous at first, the ability to respond appropriately to a potentially harmful stimulus is necessary in the long term. The fact that less than 35 percent of infants undergoing painful and invasive procedures receive any sort of pre- or post-operative pain relief needs to be re-evaluated in order to reduce physical and mental health complications associated with preterm birth."

Source: Georgia State University (2013, October 30). Pain in infancy alters response to stress, anxiety later in life. ScienceDaily.