Prenatal Pain vs. "Nociception:" Psychological Construct?

The Journal of the American Medical Association (This link is to the abstract. Subscription is required for the full article) published an article this week claiming to definitively settle the problem of whether or not children feel pain before birth.

Some of you may have read that there are serious ethical questions about the authors, two of whom are involved in the abortion industry.

But, what you probably won't read in the popular press is that the definition of pain used by the authors is a little bit more convoluted that the one you and I might use. Specific and particular jargon is important for consistent communication within a profession, however it may complicate communication between specialties. And a difference in the understanding of the definition of "pain" is vital in this case, where the authors call pain a "psychological construct." I believe that their definition is constructed.

Here's the description of the definition of pain from the article:

What Is Pain?

"Pain is a subjective sensory and emotional experience that requires the presence of consciousness to permit recognition of a stimulus as unpleasant. Although pain is commonly associated with physical noxious stimuli, such as when one suffers a wound, pain is fundamentally a psychological construct that may exist even in the absence of physical stimuli, as seen in phantom limb pain. The psychological nature of pain also distinguishes it from nociception, which involves physical activation of nociceptive pathways without the subjective emotional experience of pain. For example, nociception without pain exists below the level of a spinal cord lesion, where reflex withdrawal from a noxious stimulus occurs without conscious perception of pain.

"Because pain is a psychological construct with emotional content, the experience of pain is modulated by changing emotional input and may need to be learned through life experience. Regardless of whether the emotional content of pain is acquired, the psychological nature of pain presupposes the presence of functional thalamocortical circuitry required for conscious perception, as discussed below."

In other words, does the child feel bad about being hurt?

The stimuli that the writers are describing are the same that you and I would describe as painful. The child's brain is stimulated, to varying degrees, depending on his stage of development. Using this definition, most children would not pass their test until they were over a year old.

Some have speculated that the children may experience *more* "nociception" than a child who is mature, since the nerve stimuli can't be processed.

In the case of prenatal surgery for a wanted child (which seems to be the definition far too many use for "human child") the fetal stress hormones (mentioned in the paper) and the stimulation of the nerves themselves will affected and will actually change the way those nerves and nerve pathways will develop. With consequences that we do not yet understand.

From an article on neurodevelopment and child trauma and the periodic sensitivity to stressors:

There is some evidence to suggest that prenatal or maternal traumatic stress has significant impact on neurodevelopment -- battering the pregnant mother is also battering the developing fetus (Amaro et al., 1980).

and

The abnormal pattern of stress-mediating neurotransmitter and hormone activations during development alters the brains of traumatized children. The specific nature of these fucntional alterations is seen in all of the brain functions which are directly or tangentially related to CNS catecholamine systems. Unfortunately, the CNS catecholamines (and likely other important neurotransmitter systems altered by these experiences) are involved in almost all core regulatory activities of the brain. The brainstem and midbrain catecholamines are involved in regulation of affect, anxiety, arousal/concentration, impulse control, sleep, startle, autonomic nervous system regulation, memory and cognition.

Of course, if the child is killed, there is no more development, is there?

For those of us who love science, one of the attractions is the fact that our knowledge increases as we develop better tools to measure, record, and repeat our experiments. Neuroscience is one of the most exciting fields today, because of techniques such as functional MRI and ever more focused and reliable ways to measure development, physiology and function. Within the last two years we found out that we were wrong about the old idea that no one develops new brain cells after the age of two. We also learn more each day about the effects of stimuli and "use it or lose it" on the development and function of the brain. In the last year, it was reported that infants as young as fifteen months old are able to tell the difference between false beliefs and those that are true, a cognitive skill that went against previous evidence and testing methods.

In light of these facts, shouldn't humane medical research and treatments be cautious in order to "First, do no harm?"

As noted in this blog, since when do we allow people to kill other people just because that person can't feel pain? Would a surgeon take an unconscious person to the operating room without anesthesia? Terri Schiavo was even given IV morphine while she was being starved to death.

Edited May 26, 2009 for "labels."