How an anesthesia drug makes us unconscious

Credit: Unsplash+.

Anesthesia drugs are crucial for surgeries, allowing patients to be unconscious and pain-free.

However, scientists have long wondered exactly how these drugs work in the brain to cause unconsciousness.

Recently, researchers from MIT have discovered how a commonly used anesthesia drug called propofol makes the brain lose consciousness.

Propofol is an anesthesia drug that binds to certain receptors in the brain known as GABA receptors. These receptors usually help to calm down neurons.

When propofol attaches to them, it makes neurons less active. Scientists have now figured out that propofol disrupts the brain’s balance between stability and excitability, leading to unconsciousness.

The brain operates in a delicate balance. Neurons need to be excitable enough to communicate but not so excitable that they cause chaos.

Propofol seems to disturb this balance, pushing the brain into a chaotic state where it can no longer function properly, leading to unconsciousness.

To understand this process, the MIT team used a new technique to study brain activity. They measured electrical signals in the brains of animals that were given propofol.

These measurements were taken from four brain areas responsible for vision, sound processing, spatial awareness, and decision-making.

The researchers observed that as the animals received propofol, their brain activity became increasingly unstable. Normally, after any input (like a sound), the brain’s activity spikes and then quickly returns to normal.

However, under the influence of propofol, the brain took longer to settle down, staying overly excited. This growing instability continued until the animals lost consciousness.

To confirm their findings, the researchers created a simple computer model of a neural network. They increased the inhibition in this model, mimicking the effect of propofol in the brain. Just like in the animal brains, the network activity became unstable, leading to a loss of control, similar to unconsciousness.

The researchers explained that increasing inhibition paradoxically destabilizes the brain. Propofol boosts the inhibitory signals, which in turn inhibit other inhibitory neurons. This creates an overall increase in brain activity, leading to instability and loss of consciousness.

Understanding how propofol and other anesthesia drugs work can help make anesthesia safer and more effective. If researchers find that different anesthesia drugs cause unconsciousness through similar mechanisms, they could develop better tools to monitor and control anesthesia levels during surgery.

The MIT team is working on systems that measure brain activity in real-time and adjust anesthesia dosages accordingly. This could lead to more precise and safer anesthesia practices.

Additionally, the researchers plan to apply their technique for measuring brain stability to study other conditions, like depression and schizophrenia. This powerful method could provide new insights into various brain states and disorders.

This groundbreaking research, funded by various institutions including the National Institutes of Health and the Simons Foundation, represents a significant step in understanding anesthesia. By uncovering how propofol disrupts brain activity to cause unconsciousness, scientists can improve anesthesia safety and explore new treatments for brain disorders.

If you care about health, please read studies about how Mediterranean diet could protect your brain health, and the best time to take vitamins to prevent heart disease.

For more health information, please see recent studies that olive oil may help you live longer, and vitamin D could help lower the risk of autoimmune diseases.