Chapter 17
Never a Dull Moment - Laughter and Purpose to A Good Night’s Sleep
I am director of a newly established institute for successful ageing in Dublin. As well as being a busy clinical and research facility, the institute includes a central hub where patients, families and staff can let their creative juices flow. This physical space in the centre of a busy hospital is a source of joy and pleasure that constantly amazes with the new approaches and ideas that are generated through poetry, song, paintings, music and much more. For some, religion provides purpose. Overall, religious involvement, belief and spirituality are positively associated with a host of favourable psychological factors, such as lower depression and anxiety, better memory, better planning and organising abilities and, in general, a longer life. Our research clearly shows a positive relationship between religious practice, heart disease and death, with lower blood pressure and better immunity in religious Irish adults. While some models emphasise the link between private spiritual practice, such as meditation, and health, many others stress the added role of taking part in organised services which are further enhanced by social and cultural factors. Religious practice is also a coping mechanism and it is difficult to disentangle the positive effects of social involvement, social engagement and meditation from private coping. Although the association between religion and mental health issues, such as depression and anxiety, is complex, the overall association between religion and mental health is positive. In countries such as Sweden where the state is responsible for important aspects of quality of life, such as health and education, religion is not such a strong predictor of life satisfaction. This suggests that religion is, at least in part, a means for fulfilling certain needs where these are difficult to satisfy in other ways. Several studies have addressed the link between religion and health during life-threatening illness. For example, in people with heart disease from birth, religious faith was positively associated with better quality of life. In people on dialysis for severe kidney disease and people with heart failure and recovering from heart attacks, it was also found to improve quality of life. So, in summary, it is evident that laughter and purpose are core to longevity and good health. And, importantly, it is within our capacity to ensure that both are central in our lives and to encourage others to realise their potential.
Chapter 5: A Good Night’s Sleep
WE SPEND ON AVERAGE 26 AND A HALF YEARS OF OUR LIVES asleep, or at least in bed. For some of us, it’s a matter of putting a pillow under our heads and falling asleep. However, many experience problems with sleeping, increasing in frequency in mid-life and later. Poor sleep is an all-too-frequent problem with advancing years.
A common misconception is that our brains are inactive during sleep, whereas the reverse is the case. Rather than sleep being an inactive or a passive state, in which both the body and the brain are ‘turned off’ to rest and recuperate from the day’s waking activities, the brain goes through characteristic patterns of activity throughout each period of sleep. It is even sometimes more active when we’re asleep than when we’re awake. If we have a poor night’s sleep, we are more likely to complain of feeling ‘low’ or depressed, have trouble concentrating and suffer memory problems the following day. In this chapter, I will explain why this is the case and provide some solutions to improve sleep.
So let’s go back to basics and explore why we sleep. We are hard-wired to sleep each night as a means of restoring body and mind. Two interacting systems – the internal biological ‘clock’ and external factors such as light and noise largely determine the timing of transitions from wakefulness to sleep. These two factors also explain why, under normal conditions, we typically stay awake during the day and sleep at night.
Chapter 5: A Good Night’s Sleep
Up until the 1920s, scientists regarded sleep as an inactive brain state. It was generally accepted that as night fell and sensory inputs from the environment diminished, so too did brain activity. In essence, scientists thought that the brain simply shut down. Once they began to record brain activity, by placing sensors over the scalp and measuring brain wave ‘electricity’ – an EEG (electroencephalogram) – it became clear that sleep was dynamic. We never switch off and sleep goes through repeated stages throughout the night.
The sleep stages are defined by whether or not the eyes are moving. There are four sleep stages and I’ll briefly explain them because we spend a lot of time asleep and should understand what’s going on! During the first three phases of sleep, referred to as N1, N2 and N3, we are falling gradually into a deeper sleep – the deepest being at N3, during which the eyes are still, referred to as ‘no rapid eye movement’ or NREM. The final stage is when we dream and is the stage associated with rapid eye movements – REM sleep. These four sleep stages make up a single sleep cycle, lasting between 60 and 90 minutes. Our bodies automatically advance through each stage in sequence, waking naturally after approximately eight hours (if we are lucky). All four stages of sleep are essential for performing critical maintenance and repair within the body. They each serve different purposes and all have characteristic EEG patterns. So, what are the differences among the four stages of sleep and which ones are the most important?
Chapter 5: A Good Night’s Sleep
N1 is the beginning stage of each cycle. It lasts for about ten minutes at a time. It’s the lightest stage and the easiest to wake someone from. Next stage is N2. Almost 50 per cent of the total sleep time is spent in N2 sleep but, in this relatively brief period, our body physiology is adjusting downwards in preparation for sliding into the restorative N3 later stage of sleep. Physically, during N2, heart rate, breathing and other body functions slow down and our body temperature and blood pressure drops. Sleepers in the N2 stage are harder to wake up than those in N1. N3 is also called deep sleep, or delta sleep, due to the brain’s production of long, slow waves called delta waves. We enjoy complete unconsciousness during this phase of sleep and are almost entirely oblivious to external stimuli, including light, sound and movements. Waking is difficult and should we wake, we feel very disoriented (a condition sometimes known as being ‘sleep drunk’). It is during this phase that common sleep disorders may occur.
Deep sleep is the most physiologically profound stage of sleep. When we enter this stage, our body releases human growth hormone, a powerful substance that plays a vital role in the repair of both body and brain cells. Built-up waste products are flushed away, tissues are repaired and regrown, bones and muscles are built – especially in growing children – and the immune system is strengthened. Deep sleep is considered to be the most refreshing portion of the entire sleep cycle. It effectively erases the accumulated need for sleep that builds over a normal day of wakefulness and plays a major role in helping clear the brain for new learning the following day. Our longest periods of rejuvenating deep sleep occur in the first two sleep cycles. With each successive cycle, N3 sleep shortens and is replaced by N2 and REM stage sleep. The amount of deep sleep that we get shortens as we age. Stages N1 through to N3 are longest in young children and then gradually decrease with age.
Chapter 5: A Good Night’s Sleep
The fourth sleep stage is referred to as REM sleep – when rapid eye movements occur beneath the closed eyelids, the body is paralysed, heartbeat and breathing increase, and dreaming occurs. Because muscles in the arms and legs are temporarily paralysed during REM sleep, we are prevented from ‘acting out’ our dreams. Although we sometimes awaken convinced that we have been ‘dreaming all night’, in fact, this is the only stage in which we dream. Among the most important effects of REM sleep are stimulation of learning, processing of the day’s experiences and thoughts, and consolidation of memory into long-term storage. Experiencing sufficient REM sleep is essential for normal functioning. The symptoms of insufficient REM sleep include mental problems, such as impaired memory, hallucinations, mood swings and inability to concentrate. Physical problems include lowered core body temperatures, impaired immune systems and, in extreme cases, death.
It is worth spending a bit of time on sleep disorders because over two thirds of us have experienced one or more of these. In my experience, patients and their relatives are often concerned by sleep problems, yet the majority are nothing to worry about and will not cause future problems. Most occur because the brain is overactive during sleep and almost all become more common with age.