Recent technological advances in functional magnetic resonance imaging and optogenetics have made the brain accessible in ways that previous generations of neuroscientists could only dream of. Here are three unsolved mysteries (Mind you or "Brain you; There are many many more)!
How do we perceive pain? Have you ever withdrawn your hand after touching a hot stovetop or something by accident? of course NOT, you would never do such a thing! Maybe you "know a friend" that did. Your friend's pain sensations started with the activation of pain receptors – or nociceptors – in their hand. The information is conducted to the spinal cord, before entering higher brain areas for the perception of pain. However, a perception of pain is a subjective experience, and some people experience pain more or less severely than others. However, since you never experienced this, it is very subjective! Why? The gate control theory of pain suggests that pain signals that enter the spinal cord can be modified – amplified, diminished or completely blocked – before they enter the brain. Supporting this theory are the many accounts of how people injured on battlefields or while playing sports do not experience pain until much later. Amazing!
Next unsolved mystery! Why do we sleep and dream? While you may not have experienced pain, for sure you a candidate for sleep. We spend about a third of our lives sleeping, or we should spend about a third of our lives sleeping. Why should we invest so much time in sleep? The most straightforward answer is that sleep is restorative, and that it replenishes the body’s energy stores. However, intense neural activity during rapid eye movement (REM) sleep, the stage in which most dreams occur, suggests there may be more to the story. It is probably why infants and toddlers need up to 14 hours of sleep a day, with half of it spent in REM sleep. In adults, dreams may also play a role in brain plasticity and learning, which is why sleep-deprived adults perform worse in memory tests and tasks. Nevertheless, the actual role of sleep and dreams remain a big mystery.
Finally, How do we make decisions? Each day we are faced with hundreds of decisions which can range from trivial to life-changing. Recent data suggests that decisions are the outcome of two separate brain systems: cognitive control and the valuation network. While the valuation network supplies the brain with information about the value of each choice, it is cognitive control which keeps the overall goal in focus, preventing the brain from being overwhelmed with information.
Pain, sleep, dreams, and decision-making remains, in part, mysteries for mankind.
As Winston Churchill stated, “Criticism may not be agreeable, but it is necessary. It fulfills the same function as pain in the human body; it calls attention to the development of an unhealthy state of things".
Finally, if someone criticizes your decision-making, get your 8 hours of sleep. More than likely, the pain will be less in the AM. The Brain is amazing!