Unlike so many of these stories about near-death visits to the spiritual realm, this story does not begin in a hospital operating room following the collapse of normal heart and/or lung function. My story begins over thirty years ago when I was working in a neurochemistry laboratory trying to understand the function of dopamine in the brain of rats.
Today, many people have heard about dopamine – the feel good, euphoria-producing brain chemical. Scientists have invented drugs to manipulate dopamine in order to treat our anxiety, addictions and depression. We now understand how many different popular drugs of abuse, such as cocaine and ecstasy, interact with it. Thirty years ago I was simply trying to understand its role in controlling the behavior of rats.
Measuring changes in dopamine is challenging because when the temperature of the body and level of oxygen in the blood drops, even a little, brain dopamine is very quickly converted into an entirely different molecule call 3-MT. Thus, in the few seconds that transpired between when the I removed the rat’s brain and then began to measure dopamine levels in the tissue, almost sixty percent of the dopamine had been transformed into 3-MT. My solution was to add up the number of 3-MT molecules with the number of dopamine molecules and assume that the total represented the number of dopamine molecules that were originally in the brain. Today, this is common approach.
At the time, no one knew whether 3-MT had any action in the brain. Indeed, until a few years ago most textbooks stated that 3-MT was completely inactive in the brain. In addition, thanks to the fact that our brain receives such an abundant and uninterrupted supply of blood and oxygen from our heart and lungs, its level in the brain tends to be very low. Thus no one really paid much attention to this little molecule.
Things have changed. Recently, our understanding of the actions of 3-MT in the brain improved when neuroscientists discovered the Trace Amine Associated Receptor 1 (TAAR1). TAAR1 is important because drugs that are powerful producers of euphoria and hallucinations, such as amphetamine, methamphetamine, LSD, 2C-B and ecstasy, have all been shown to interact intimately with this receptor.
The question that remains unanswered is whether during a near-death experience the blissful spiritual world that is full of love and comforting thoughts are due to the abrupt hypoxic/anoxic hypothermia-induced increase in the level of 3-MT, a molecule that may be able to mimic some of the most powerful drugs of abuse ever discovered, in your brain …or you actually visited heaven. Fortunately, we all get to decide for ourselves.
© Gary L. Wenk, Ph.D., author of Your Brain on Food (Oxford, 2010)