Have you experienced a terrible stressful day, then after several days, nightmares disrupt your sleep? You randomly wake up in the middle of the night with dreadful anxiety? If yes, this study could be the explanation behind it.
Researchers from India conducted a study that showed the long term effect of single episodes of severe stress. Experts said these events may lead to delayed psychological trauma.
The research, led by by Sumantra Chattarji of the National Center for Biological Sciences and the Institute for Stem Cell Biology and Regenerative Medicine, inStem, confirmed that single stressful events cause electric activities to amygdala.
Amygdala is the part of the brain located in the temporal lobe that plays a huge role in emotional reactions, memory and decision making. Activities that happen in amygdala during stress are linked to post-traumatic stress disorder, or PTSD.
Experts said, they noticed changes in the structure of the nerve cells in amygdala during severe stress. These incidents cause formation of new nerve connections also known as synapses.
Lab results in mice showed that acute stress has no instant effects in the brain. However, after 10 days, the rats began developing anxiety and changes in the structure of the brain, particularly the amygdala. The molecule known as the N-Methyl-D-Aspartate Receptor or NMDA-R is behind the episodes of anxiety, it is an ion channel in nerve cells that also plays a role in memory.
"We showed that our study system is applicable to PTSD. This delayed effect after a single episode of stress was reminiscent of what happens in PTSD patients," said Chattarji to Science Daily
. "We know that the amygdala is hyperactive in PTSD patients. But no one knows as of now, what is going on in there," he adds.
According to researchers, by blocking the NMDA-R, the effects of stress to the brain may be prevented.
"So we have for the first time, a molecular mechanism that shows what is required for the culmination of events 10 days after a single stress," Chattarji said. "In this study, we have blocked the NMDA Receptor during stress. But we would like to know if blocking the molecule after stress can also block the delayed effects of the stress. And if so, how long after the stress can we block the receptor to define a window for therapy."