Find the answer right away why when you have a difficult time, you often raise your hand to scratch and think.
Many people believe that the obvious gesture like scratching the head when we are thinking is a natural action, handed down by ancient people to modern people.
And that the image of scratching the other head represents the mind disentangling while thinking about something. Is it not? 
Columnist Matthew Alice shared that: ” A common explanation for any head-to-head movement is frustrated aggression . It’s akin to an ancestor’s gesture of hole-eating. “.
Alice also offers a bit of an explanation for this head-scratching behavior : “When we are struggling with certain problems, we express frustration, sometimes anger. Before we know it, our hands are already in the air. fluttering in the air.
In modern times, it is rude to use force against the questioner. So instead we deflect attention from the movement and scratch or rub the head, chin or neck.”
Does this head-scratching image represent the mind untangling while thinking about something?
In a 2009 article, author and former FBI agent Joe Navarro shared : “When we are stressed, our brains need more hand-to-body actions (squeezing hands, rubbing forehead, touching lips…) These actions partly reduce the negative stimulation to the extremities, making us more fearful and stressed …”.
Recent research seems to have taken this stress hypothesis and developed further surprising results.
In a 2017 study published in the journal Scientific Reports, scientists observed 45 rhesus monkeys and discovered an interesting fact. They often scratch their heads during times of high stress (such as in front of strange monkeys or their superiors).
It turns out that the scratchers themselves are less likely to be attacked by threatening strangers.
” Head scratching can be a sign of stress . As a result, attackers often avoid attacking stressed individuals because they may have weakened some of their strength due to stress or will behave inappropriately. At that point, the offensive sometimes becomes dangerous or unnecessary , “according to the above study.
So while there’s no single explanation for this head-scratching behavior, it seems likely that expressing anxiety through this stereotyped behavior can help you gain more favor or tolerance from others. there!