Earworms can be triggered by singing along to music, and are classed as thoughts that occur beyond our conscious control, similar to spontaneous memory recollections and mind wandering.
Scientists say the problem with earworms is the more we focus on whether we've been able to get rid of it, the more our brain is likely to go back to the song loop.
However, these tricks can help it along:
• Chew some gum
Researchers at the University of Reading found jaw movement can interfere with short term memory, and provide enough distraction to relieve nagging thoughts.
•Replace the song with something else
While it may sound like you're risking another earworm situation, some people find using "cure" songs can push out the unwanted noise. Classical music is said to be the best.
•Solve a Sudoku:
Western Washington University researchers found that performing complex non-verbal tasks can help keep earworms from getting established in the first place. However, just make sure the puzzle isn't too difficult, challenging tasks can make mind to wander, and trigger the earworm's return.
2. Why does the mind wander?
While our brains are capable of extremely complex thoughts, the grey matter's default mode is daydreaming. It takes effort to switch to focus mode, and if a task is repetitive, the mind can wander.
Scientists call these momentary lapses "maladaptive brain activity changes", and can pinpoint them with MRI scans a good 30 seconds before the person realises they are doing it.
3. Why do we hit the snooze button?
While that extra snooze time feels like the best thing ever, it would be better for us if we set the alarm later and got up straight away.
Sleep goes in cycles, starting off with dozing, then 10 -20 minutes of light slumber, before we slip off into deeper sleep. The cycle goes for 90 minutes, and as the night goes on, the light sleep phase turns to dreaming.
The problem with the snooze button is the cycle has already been broken, and any extra bursts of light sleep will feel unsatisfying and make getting gup even harder.
4. Why do our voices sound different when played back to us?
Everyone has asked at some point in time, "do I really sound like that?". When we hear other people speaking, the sounds travel through the air and hit the eardrum, which causes it to vibrate and send signals to the brain.
However, when we speak, the sound reaches our brains in an entirely different way. When we make sounds with our vocal cords, the soft tissues in the head and neck vibrate, along with the bones in our face. In turn, these extra vibrations make our voices sound lower.
When we hear a recorded version of our voice, we aren't getting these undertones, and the higher pitch can sound very different to what we are used to hearing.
5. Why do we see faces in things?
Whether it's the man on the moon or a knot of wood that seems to be staring at you, we often see faces in strange places. It's called pareidolia, and occurs in a highly-programmed part of the brain called the fusiform face area, which is specially adapted to detect faces.
Researchers have seen on brain scans that whenever we see something that even vaguely resembles a human face, this area of the brain lights up.
Scientists at the University of Toronto found that this rapid processing occurs in the prefrontal cortex, which handles what we expect to see and the posterior visual cortex, which processes what we actually see.
6. Why does wet fabric always look dark?
This one is simply an optical illusion. Scientists call it the "index of refraction", meaning how much light is reflected off fabric, and how much moves through it.
When material gets wet, the light hitting it has to travel through water instead of air, which alters its path and causes the light particles to bend. So rather than reflecting back towards the eye, more light is scattered within the fabric, making the colour appear darker.