Can children's dreams anticipate events that will happen nearly 40 years later? Yes, according to my most recent paper published in The Lancet's eClinicalMedicine journal.
It was found that children who have regular bad dreams and nightmares between the ages of seven and 11 might be nearly twice as likely to develop cognitive impairment (the core feature of dementia) by the time they reach the age of 50. And they may be seven times more likely to be diagnosed with Parkinson's disease by the age of 50.
I discovered that middle-aged and older individuals who have frequent bad dreams and nightmares might be twice as likely to develop dementia or Parkinson's in the future.
This prompted me to consider whether lots of bad dreams during childhood might predict the development of dementia or Parkinson's disease later in life.
I gathered data from the famous 1958 British birth cohort study, which tracks the lives of all children born in England, Scotland, and Wales over the three-week period starting March 9 to November 9 of 1958.
Mothers answered a variety of questions about their children's health, including whether or not they had had bad dreams in the previous three months (yes/no).
I classified the 6,991 children into three categories: "never," "occasional," or "persistent." The children with more frequent bad dreams were more likely to develop cognitive impairment or become Parkinson's by the time they turned 50 (2008).
The results were clear. The more frequently children experienced bad dreams, the greater their likelihood they would develop cognitive impairment or be diagnosed with Parkinson's disease.
People who had persistent bad dreams were 76% more likely to develop cognitive impairment and 640% more likely to develop Parkinson's, both boys and girls.
These findings suggest that regular bad dreams and nightmares during childhood might decrease the likelihood of developing advanced brain illnesses such as dementia or Parkinson's disease later in life. A reduction in bad dream frequency in early life might also be an early strategy to prevent both conditions.
Il will take further studies to verify if these conditions are real.
The frequency with which we have nightmares as children is in large part influenced by our genetics. One gene known to increase our risk of regular nightmares (PTPRJ) is also linked to an increased risk of Alzheimer's disease in older age. It's possible that nightmares and progressive brain diseases are both caused by a shared set of genes.
Both theories, according to my hunch, may be correct. Nightmares and progressive brain diseases are linked by shared genetics, as well as through nightmares directly causing brain illnesses by disrupting the brain-restoring functions of sleep.
Don't be apprehensive.
Although these findings may be alarming, when considered in their proper context, they aren't. Only 268 (4%) of the roughly 7,000 children included in my investigation had persistent bad dreams, according to their mothers. Only 17 of these children had developed cognitive impairment or Parkinson's disease by the age of 50 (6%).
So it is quite probable that the majority of people who have persistent bad dreams in childhood will not develop early-onset dementia or Parkinson's.
The danger of progressive brain diseases is increasing rapidly in old age. Being aware that bad dreams in childhood may indicate a higher risk of dementia or Parkinson's later in life suggests that there may be a window of opportunity to employ simple strategies to reduce those risks. And for young people with frequent distressing dreams that persist over time, getting help for nightmares might be one such approach.
My next project is to investigate the biological reasons for bad dreams and nightmares in children. Electroencephalography is a brainwave measurement technique.
The ultimate goal is to improve people's sleep quality and mental health and reduce their risk of dementia or Parkinson's disease later in life.
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