Why we hate unpleasant sounds?

Brain imagining reveals that when exposed to unpleasant noise, amygdale modulates the response of the auditory cortex and heightens its activity, creating negative reaction.
There is a reason why you hate scratching sound-for example, of a knife on bottle or a fresh chalk on a blackboard-says a study by Newcastle University scientists.
The study in Journal of Neuroscience finds an interation between auditory cortex, the region of brain that process sound, and amygdale, which processes negative emotions.
Brain imagining reveals that when exposed to unpleasant noice, amygdale modulates the response of the auditory cortex and heightens its activity, creating negative reaction.
"It appears there is something very primitive kicking in," says Dr Sukhbinder Kumar, the paper's author from Newcastle University . "It's a possible distress signal from the amygdale to the auditory cortex".
Also sounds in the frequency range of around 2,000 to 5,000Hz are found to be unpleasant. When exposed to such piercing sounds, amygdale modulates the auditory part of the brain creating unpleasant emotions. This dosn't happen with soothing sound of bubbling water.
"This is the frequency range where our ears are most sensitive. Although there's still much debate as to why our ears are most sensitive in this range, it does include sounds of screams which we find intrinsically unpleasant,"Dr Kumar says.
The study might help better understanding of the medical conditions of decreased sound tolerence of some people, which is known as hyperaucusis or misophonia (literally,"hatred of sound").
Next time, when you shy away from the scratching noice of an electric driller think about of Amygdale's hand behind it.

Good intentions and Bad results

Good intentions are always lauded, because they could lead to good results. But that is not always the case.
Ask the nanny who restored an antique fresco in Spain; probably she could say how good intentions often bring bad results.
This woman in her 80s whose name is withheld to avoid embrassment to her has been a regular visitor at Mercy Church in Borjanos, Southern Spain.
A 120 year old fresco of Christ by Gracia Martinez has been a major attraction for worshipers here. The aged lady, in many of her regular visits, noticed that the fresco was fading and the paint falling off, mutilating the image, though the face was almost intact.
As the plaster portrait began to crumble owing to damp, the nanny couldn't stand idly by.
She stepped in-and that was it. Without even having a word with the authorities, one day she marched in, armed with paint and brush.
Believing herself to be a painter who could restore the ageing art work, she went at it. She did her best to get right the smudged image on the wall and felt really happy after doing her bit.
But the fellow worshipers, who until the previous day had worshipped a Christ image that was universally the same, were shocked, because what now they witnessed on the wall was a far cry, something they couldn't visually adjust with.
Because, well, the fresco turned into a comic movie image of werewolf, nothing short! Now the authorities stepped into assess the fresh damage caused by the nanny's private restoration project.
As resentment grew, the local cultural foundation received a donation from the granddaughter of the 'artist' to bring back the fresco's former glory.
But people, however disappointed by the bad art, were not overly noisy in their grumbling against the artist, because she had only good intentions when she had done it.