, Dr Louise Faber and her colleagues at the Queensland Brain Institute (QBI) have demonstrated how noradrenaline, the brain's equivalent of adrenaline, affects amygdala, an almond-sized and -shaped brain structure, long linked with a person's mental and emotional state.
Thanks to scientific advances, researchers have recently grasped how important this 1-inch-long structure really is.
Derived from the Greek for almond, the amygdala sits in the brain's medial temporal lobe, a few inches from either ear. Coursing through the amygdala are nerves connecting it to a number of important brain centers, including the neocortex and visual cortex.
Now the Queensland scientists say the hormone noradrenaline could be controlling chemical and electrical pathways in the brain.
"This is a new way of understanding how neurons form long term memories in the amygdala," Dr Faber said.
"Our strongest and most vivid human memories are usually associated with strong emotional events such as those associated with extreme fear, love and rage."
"For many of us, our deepest memories are mental snapshots taken during times of high emotional impact or involvement," she said.
"Some aspects of memory formation are incredibly robust - and the mechanism we've discovered opens another door in terms of understanding how these memories are formed."
Dr Faber said her team's discovery could help other scientists to elucidate new targets, leading to better treatments for conditions such as anxiety disorders and post-traumatic stress disorder.