How many of us have had sleepless nights after watching a scary movie? It may be tempting to seek solace in slumber after a traumatic event, but a recent study found that sleeping too soon after trauma might lead to increased post-traumatic stress disorder symptoms. Researchers believe that sleep deprivation disrupts the consolidation of trauma memories— a hypothesis that jibes with the current understanding of the role of sleep in strengthening emotional memories.
Once that memory is ingrained, however, sleep could provide an opportunity for treatment. Sleep deprivation can also reduce the impact of traumatic brain injury (TBI). To support this hypothesis following are two separate studies.
- Two groups of rodents were exposed to a predator’s scent, a traumatic event for a mouse. For six hours afterward, one group was prevented from sleeping, whereas a control group was not. The sleep-deprivation group displayed fewer physiological markers of stress than the control group and less PTSD-like behavior, such as freezing and a heightened startle response.
- In a second study rats with traumatic brain injury (TBI) sustained less damage when they were kept awake for 24 hours after the injury.
Taken together, these findings suggest that after a violent, traumatic event—such as a car accident—staying awake for a while could afford both physical and mental protection.
Scientists have long known that once we nod off, certain memories grow stronger. One of the main reasons why traumatic memories are prominent in our heads is due to flaws in sleep’s forgetting process. Can proper sleep make the trauma go away which has already set in?
Current treatments for PTSD—and other persistent negative memories — often rely on exposure therapy, which inoculates patients against their fear trigger by creating a new, safe memory that springs to mind more often than the old, frightening memory. But the old memory remains. To truly diminish its power, this research suggests, we must target the unconscious mind and help the brain forget.
There are studies which indicate that sleep might offer a window of opportunity for weakening memories and providing relief from lingering reminders of trauma.
Neuroscientists believe that during sleep, a memory-elimination routine cleans out obsolete information by physically weakening synapses, the junctions between communicating neurons.
Gina Poe, a neuroscientist at the University of Michigan, found in mice that for synapses to lose strength, levels of the neurotransmitter noradrenaline must drop. Noradrenaline levels typically fall during REM sleep in rodents and humans, but in people with PTSD the amount stays high throughout sleep. Normalizing noradrenaline with pharmaceuticals could absolutely be a key target to actually cure PTSD through normal sleep.
In another experiment memory remodeling was hijacked in sleeping mice in order to make a traumatic association less scary. The mice were conditioned to fear the scent of jasmine flowers by pairing the smell with a foot shock. Under normal circumstances, the smell would reactivate and bolster the memory, a process that requires newly made structural proteins. The researchers gave some mice a drug that prevented the manufacture of these building blocks in a key fear-memory area. When these mice woke up, they no longer responded to the odor with fearful behavior, indicating that the memory had been successfully disrupted.
The findings might someday translate to a new kind of sleep-based therapy in people whose traumatic experiences are tied to specific sounds and smells—such as the noise of a bomb going off—that can be presented to their sleeping brain.
Maybe it’s a good way of doing away with sleep immediately after watching a scary movie, and on the other hand if the boogeyman keeps haunting you a sleep based therapy could be the right remedy.