10 Crazy and Amazing Things You Should Know About Your Brain
1. The brain itself cannot feel pain.
Explanation: This can be quite hard to get your head around, but the brain does not have any pain receptors. To feel pain, cells called sensory neurons (or more specifically, nociceptors) are activated during painful experiences, for example if you stub your toe. The sensory neurons then send electrical signals to the spinal cord, which relays this signal to the brain, where it is interpreted as ‘pain’.
So while the brain is where the message of ‘pain’ is perceived for other areas of the body, the brain itself cannot ‘feel’ pain. This explains why brain surgeons are able to probe through the brain on awake patients during neurosurgery!
4. The brain is the fattest organ in the body!
Explanation: Your brain may consist of at least 60% fat. Fats or lipids are a major component of cell membranes and are also crucial for forming the fatty membrane (myelin sheath) that is wrapped around brains cells (neurons). This fatty sheath is key for insulating these cells to enable fast conduction of the electrical impulses (called action potentials) used for communication in the brain.
5. Fear can boost sexual attraction
Explanation: The brain gives rise to all emotions including fear and attraction. In a classic study, probably familiar to most psychologists, men were approached by a female experimenter after they crossed either a safe bridge, or a high rickety suspension bridge. Men who had crossed the rickety bridge rated the experimenter as more attractive than those who had crossed the stable bridge (Dutton & Aron, 1974).
The researchers suggested that the men may have misattributed their arousal (i.e. increased heart rate). Essentially, they believed that they were feeling sexual arousal at the sight of the female, instead of feeling the leftover physiological arousal from the fear of walking across the suspension bridge. So next time opt for an adventurous first date!
2. Brain cells are cannibals
Explanation: Autophagy is a normal cellular process, which performs a housekeeping role in the brain, recycling diseased, dead or damaged cellular parts for energy, or removing them.
Worryingly, recent research suggests diets and drugs can cause the brain to start eating itself. Some appetite-sensing neurons in part of the brain called the hypothalamus (Singh et al., 2011), have been found to ramp up autophagy in times of starvation. More recently, high doses of cocaine were shown to result in this housekeeping process removing key cellular components such as mitochondria, which are responsible for making energy for the cell (Guha et al., 2016). These findings should make us think about our brains cellular systems and how we affect them.
4. We do not know how general anesthetic affects the brain!
Explanation: General anesthetic is familiar to most of us, whether we have been under aesthetic or know someone who has. It is a drug which brings about reversible loss of consciousness and is widely used in hospitals .
However, it may come as a surprise that scientists and doctors do not know the exact mechanisms of action. In other words, the underlying biology of how this drug exerts its effects on the brain are still not known. Part of the problem is that the chemical structures of general anaesthetics are diverse, yet they all have the same desired effects. Hence, there are many differently structured drugs giving rise to the same outcome, so that there is no obvious drug structure–activity relationship. Interesting...
7. Your brain is plastic.
Explanation: Brain plasticity refers to lasting changes to that brain that occur through our life. Practicing a particular skill can result in strengthened neural connections in the brain which represent this skill.
For example, London taxi drivers who have to remember many different routes were found to have a larger part of the hippocampus, an area of the brain involved in memory compared to bus drivers who have fixed routes (Maguire et al., 2006). This classic study shows how the skills we practice and directly change the brain. Additionally, the brain is more malleable than previously thought. Even in old age, the brain can still make new connections in response to learning a new skill . Therefore, science has reassured us numerous times that you can teach an old dog new tricks!
8. The brain is active when we are asleep
Explanation: From personal experiences, we know a tired brain can result in suboptimal functioning, e.g. reduced concentration. Therefore, it is intuitive to think that sleep serves some sort of restorative function, where the brain rests and recharges. However, sleep is an active process, as during a certain phase of sleep (REM sleep), EEG activity patterns are indistinguishable to when the person is awake.
Why we sleep is still a mystery puzzling scientists, but we do know that sleep is important for memory and learning. New research also suggests the brains plumbing system called the glymphatic system, is active during sleep (Xie et al., 2013). Thus, one reseason we need sleep may be to clean up the brain and flush out neurotoxins. Therefore, we should not feel guilty for those extra hours in bed if sleep is such an active process!
9. You use MORE than 10% of your brain
Explanation: The greatest myth in neuroscience: 'we only use 10% of our brain'. The origin of this myth is unknown but, pop culture perpetuates it, see the film Lucy, released in 2014. Perhaps it is appealing for people to think that they have the potential for improvement, that they could become more intelligent, creative or successful if only the other 90% could be unleashed...
Why this statement is a myth warrants a full article, however, in a nutshell:
- Brain scans show activity through the entire brain, even at rest.
- If a person loses a limb, the redundant brain tissue representing that limb is recruited by neighboring brain regions for new functions. Thus, the brain uses all available tissue.
- The brain is costly in terms of energy. It represents 2% of our total weight, but uses 20% of our total energy, thus it would seem daft to have evolved a brain 10 x the size we need.
10. Brain communication is both electrical and chemical
Explanation: Brain cells, (neurons) communicate between different cells using chemical signals, called neurotransmitters. However, communication within cells is electrical.
The main reason for this, is because electrical impulses are better at travelling longer distances (within the individual cells) as they are continually regenerated and therefore do not degrade, whereas chemical signals weaken over distance, however the gap between cells is small, so chemical communication is fine as it does not need to travel far! Mother nature deigned the brain well!
BONUS FACT: Famous Brains
When Einstein died in 1955, doctors didn't just save a lock of his wild white hair. Dr. Thomas Harvey removed Einstein's brain for scientific research- but then it vanished..
Much later in 1978 Steven Levy, a journalist tracked down Dr. Harvey in Kansas, and the doctor admitted he still had the brain, sliced up in two jars and preserved in formaldehyde!
There you have it..
10 cool things about the brain that you now know!