By IANS
New York : Bad times are more easily remembered than good ones, US scientists have found.
Negative emotions like fear and sadness trigger increased activity in a part of the brain linked to memories.
According to researchers these emotionally charged memories are preserved in greater detail than happy or more neutral memories, reported the online edition of health magazine WebMD.
However, they may also be subject to distortion. For example, eyewitnesses to a shooting often report seeing the gun vividly, but they may not remember precise details of their surroundings, it said.
Studies using functional magnetic resonance imaging (FMRI) have shown negative events stimulate activity in emotion-processing regions of the brain, such as the orbitofrontal cortex and the amygdala.
The more these emotional centres are activated by an event, the more likely an individual is to remember specific details linked to the emotional aspect of the event, like the appearance of the gun, and perhaps less likely to remember more mundane details like a street address.
Elizabeth Kensinger of Boston College in a review of research on the topic in Current Directions in Psychological Science says this technique of preserving bad memories may have evolved as an evolutionary tactic to protect against future life-threatening or negative events.
They say more studies on how we remember bad memories are needed to help understand posttraumatic stress disorder as well as evaluate the reliability of eyewitness testimony.