When sleep becomes the victim of our late-night lifestyles, a monstrous wave of violence can rise in its place. The darkness between midnight and dawn, researchers say, is a breeding ground for impulsive, deadly acts, with suicide and homicide rates surging to terrifying heights. A dangerous cocktail of alcohol, existing mental health challenges, and youth increase the likelihood of a violent act after midnight.
Dr. Andrew S. Tubbs, MD, PhD, from the University of Arizona College of Medicine, and his team have meticulously pieced together a grim tapestry of data spanning 15 years, confirming that the witching hour is not just a spooky tale – it’s a real-life danger zone.1 When our internal clocks are thrown out of sync, our minds become a battleground, they claim, where reason is held hostage and destructive urges are unleashed.
This darkness, however, doesn’t prey on everyone equally. The young, it seems, are particularly vulnerable to these effects. Young adult brains are still under construction and Tubbs reports that their underdeveloped impulse control is easily hijacked by sleep deprivation.1
Late night drinking they say, can be like a molotov cocktail. The effects of alcohol in lowering their inhibitions can cause an explosion of aggression, fueled by the shadows. And for those already grappling with the demons of depression or relationship turmoil, the night becomes a suffocating shroud, amplifying despair and conflict.1
The implications are clear: a good night’s sleep is not just a luxury; it’s a shield against the darkness within us all. As we strive to understand and mitigate the devastating consequences of violence, this research shines a stark light on the crucial role that sleep plays in safeguarding our minds and our communities.
Seeing in the darkness
To investigate the link between sleep disruption and violent behaviors, the scientists delved into two extensive databases. The primary source was the National Violent Death Reporting System (NVDRS), a comprehensive record maintained by the CDC, which provided detailed information on suicides and homicides across the US from 2003 to 2017. To account for the fact that fewer people are typically awake during the night, the study also incorporated data from the American Time Use Survey (ATUS). This survey, conducted by the Bureau of Labor Statistics, gave researchers a nationally representative picture of sleep patterns across the country.
Armed with this wealth of information, the researchers embarked on a two-pronged analysis. First, they precisely calculated the risk of suicide and homicide for each hour of the day, carefully adjusting for the estimated number of people awake at that time. This approach allowed them to isolate the true impact of nighttime hours on these behaviors. Second, they delved deeper, examining whether risk patterns differed significantly among various groups, such as different ages, alcohol users, or people experiencing mental health challenges. By using advanced statistical methods they were able to pinpoint specific factors that could make certain groups more vulnerable to the negative effects of disrupted sleep.
What happens to your mind after midnight?
The risk of suicide peaks between 2:00 and 3:00 AM, a five-fold increase compared to the 24-hour average. Similarly, the risk of homicide reaches its apex around 2:00 AM, representing an alarming eight-fold increase.
Young adults, particularly those between 15 and 34 years old, face a heightened suicide risk in the early morning hours (around 4:00 AM), while older adults (65+ years) have an increased risk later in the morning (around 6:00 AM). Hispanic individuals also experience increased risk between 10 PM and 3 AM. Alcohol consumption, especially at high levels, is linked to elevated risk during the night for both suicide (8:00 PM-4:00 AM) and homicide (11:00 PM-5:00 AM). Individuals embroiled in partner conflicts see their risk spike in the late evening (8:00 PM-11:00 PM) and early morning (1:00 AM-3:00 AM). Notably, women are found to be more vulnerable to homicide in the early morning hours between 4:00 and 9:00 AM.
Why our brains betray us when darkness falls
Immature brain development in young adults is a huge risk factor. The suicide risk for those between 15-24 years of age is three times greater, and those between 25-34 is two times greater, than those aged 45-54. The prefrontal cortex, which is responsible for impulse control and decision-making, is not fully developed in young adults.2 Nocturnal wakefulness may further strain their already limited executive function, leading to increased risk-taking.
Alcohol impairs judgment and disinhibits behavior, making people more prone to aggression and impulsivity.3 This effect is likely amplified by the already heightened emotional vulnerability and dysregulation associated with being awake at night.
The unexpected finding of increased suicide risk in older adults around 6:00 AM could be due to sleep inertia, a state of grogginess and impaired cognition that occurs immediately after waking up.4 Older adults are more susceptible to sleep inertia, which might temporarily worsen their decision-making abilities.
Sleep: the lighthouse that keeps us safe in the dark
The study results strongly support the “Mind After Midnight” hypothesis: Burning the midnight oil can cast a dark shadow over your mind. Staying awake when your body craves sleep disrupts your brain’s natural rhythms, leaving you prone to negative thoughts, risky actions, and impulsive choices.5
The heightened risk of suicide and homicide during the nighttime hours suggests that disrupted sleep and nocturnal wakefulness play a significant role in these behaviors. This highlights the importance of considering individual characteristics (age, alcohol use, relationship conflict) when assessing risk and developing interventions.
We now need tailored interventions for different groups, addressing the unique vulnerabilities associated with sleep disruption.
References
- Tubbs AS, Fernandez FX, Klerman EB, et al. Risk for Suicide and Homicide Peaks at Night: Findings From the National Violent Death Reporting System, 35 States, 2003-2017. J Clin Psychiatry. 2024;85(2):23m15207. Published 2024 May 29. doi:10.4088/JCP.23m15207
- Teffer K, Semendeferi K. Human prefrontal cortex: evolution, development, and pathology. Prog Brain Res. 2012;195:191-218. doi:10.1016/B978-0-444-53860-4.00009-X
- Day AM, Kahler CW, Ahern DC, Clark US. Executive Functioning in Alcohol Use Studies: A Brief Review of Findings and Challenges in Assessment. Curr Drug Abuse Rev. 2015;8(1):26-40. doi:10.2174/1874473708666150416110515
- Silva EJ, Duffy JF. Sleep inertia varies with circadian phase and sleep stage in older adults. Behav Neurosci. 2008;122(4):928-935. doi:10.1037/0735-7044.122.4.928
- Tubbs AS, Fernandez FX, Grandner MA, Perlis ML, Klerman EB. The Mind After Midnight: Nocturnal Wakefulness, Behavioral Dysregulation, and Psychopathology. Front Netw Physiol. 2022;1:830338. doi:10.3389/fnetp.2021.830338
