Babies have different sleeping needs depending on their age. Typically, a newborn sleeps much of the time, but as the baby grows, the total amount of sleep gradually decreases, but the nighttime sleep increases.
Most babies do not begin sleeping throughout the night without waking, not until about three months of age. Two-thirds of the babies generally sleep through the night on a regular basis when they are six months old.
But babies may begin to have difficulty sleeping because of separation anxiety, overstimulation, or overtiredness.
Sleeping Problems Linked to Mental Disorders
A longitudinal study from a team of researchers at the University of Birmingham's School of Psychology has found that specific sleep problems among babies and very young children can be linked to mental disorders as adolescents.
The researchers studied questionnaire data from the children in the 1990s in which they recruited pregnant women of 14,000 babies when it was set up almost three decades ago.
Not only they found that sleeping problems in babies and young children were linked to having mental disorders, but they also discovered that children with shorter periods of sleep or went later to bed were more likely to be associated with Borderline Personality disorder (BPD) in their teenage years.
"We know from previous research that persistent nightmares in children have been associated with both psychosis and borderline personality disorder. But nightmares do not tell the whole story -- we've found that, in fact, a number of behavioral sleep problems in childhood can point towards these problems in adolescence," explains lead researcher Dr. Isabel Morales Muñoz.
They examined more the questionnaires from more than 7,000 participants who reported psychotic symptoms in adolescence and more than 6,000 questionnaires who reported symptoms of BPD. The study, known as the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort was set up by the University of Bristol and published in JAMA Psychiatry.
The results showed particular associations between infants at 18 months who woke up frequently during the night and had less regular sleep from six months old, with mental disorders in adolescence.
This supports the idea that insomnia contributes to psychosis, but that these difficulties may have been present even before the onset of the psychotic problem.
Furthermore, BPD symptoms were correlated with the sleep patterns of children at the age of three-and-a-half years who had less sleep during the night and went to bed later. These suggest a specific pattern to developing BPD, with a separate pathway linked with psychosis.
Read also: Can You Recover Lost Sleep on Weekdays by Oversleeping Over the Weekends?
Sleep: An Important Underlying Factor for Effective and Early Interventions
Researchers investigated if symptoms of depression in children aged ten years old could have mediated the links between infant sleep and mental disorders in adolescents. They found that depression mediated it but is not observed in BPD, which suggests that the existence of a direct association between sleep problems and BPD symptoms.
Study senior author Professor Steven Marwaha said that it is important to study the adolescence period when the onset of many mental disorders happens, including BPD and psychosis, due to hormonal changes in this stage.
The scientists concluded that sleep might be one of the most underlying factors influencing the effective and early intervention.