Older Consumers
Are they really different?
The Third Age Consumer
We all finally reach the same stage when physical and mental disability begins to restrict our ability to live a normal life. Laslett, a British historian, called this the Fourth Age. My father only had a handful of years between retiring and the start of his Fourth Age. Laslett termed that period after retirement, the Third Age and saw it as a golden period. There are now a huge group of Third Age consumers. They have retired but are capable of consuming as they have always done. They have the health and mental capacity to travel, eat out, and are heavy users of all services. I am a Third Ager and am enjoying it. In a single generation then, the onset of the fourth age has moved back to at least eighty-five. Medical science means the Third Age has become a twenty-year span.
Laslett defined the First Age as the period until we start work. The Second Age runs from then until we retire. They are not fixed chronological ages. The Third Age or the Second Age do not start on a particular birthday.In describing “old age” and ageism I have chosen to use Laslett’s model. It is not precise and is not tied easily to chronological age. The Fourth Age does not start on a particular birthday and is a point on a continuum. Retirement is no longer a fixed point; all be it that the date of pensionable retirement has remained remarkably fixed. It does however convey the phases of life in a way that artificially dividing up old age into sixty-five to seventy five, seventy five to eighty five etc., does not.
We are not designed to retire
A recent book by an eminent Harvard professor suggests that humans did not evolve to retire. According to David Lieberman, an evolutionary biologist and anthropologist, mankind ages uniquely. For most species, evolution loses interest once the individual passes reproductive age. Chimpanzees, seldom survive past the age of 50, soon after they stop being able to reproduce. In evolutionary terms they are obsolete and redundant. Why then did evolution decree that humans could live much longer?
The answer lies in the capacity of humans to have a higher birth-rate and sustain their children. This gives us an evolutionary competitive advantage versus other primates. A Chimpanzee mother needs to forage two thousand calories per day. This is enough to maintain their own wellbeing and to have a little capacity left to feed their child. They can thus raise a single infant at a time and do not fall pregnant again until that child is self-sufficient.
Archaeological research shows a typical human hunter gatherer mother with a six-month infant, a four-year-old child, and an eight-year-old juvenile. The only way that the mother could feed her family is with the support of the older members of the community. This is also shown in the few hunter gatherer societies that remain today. The grandparents are active foragers for roots and berries to the end of their lives. They provide food for their “grandchildren”. They never stop “working” and Leiberman argues that this is the reason they live so long. Elderly humans are anything but “biologically obsolete” .
He argues nature has provided them with the ability to maintain their bodies. Hard work keeps the elderly hunter gatherer fit and allows them to live longer. The activity in which they engage stimulates recovery mechanisms in the body that also slow ageing.
Older Customer Satisfaction
Nothing can be more ambitious than the American Customer Satisfaction Index. This survey measures whether all US consumers are happy with all their suppliers. It was set up in 1994 by the University of Michigan. Each year since, it has measured customer satisfaction. They do this for the products and services of over two hundred suppliers. These suppliers come from different industries as well as US Government Services. The companies may change over time, but the survey analyses sectors or industries. The data is collected from a representative sample of the US population. It uses a telephone survey of more than seventy-five thousand people.
The Overall Satisfaction Index itself is an amalgamation of all the data into a single number. This reflects how satisfied the American consumer is at any given date. At the end of September 2020 it stood at seventy-three point seven out of hundred. It has been falling since 2018 from a high of seventy seven. COVID accelerated the decline. It has remained static for the last two quarters. The results are also show how satisfied people are with different service sectors over time. COVID has certainly hit those sectors suffering from supply chain shortages.
A group of researchers have used the data in a different way. They assessed the impact of age on satisfaction. Obviously the survey collected lots of demographic data. This includes income, gender, education level and of course age. They showed conclusively that older people are more satisfied than younger respondents.
Statistically the relationship is extraordinarily strong. With forty-five different industries over twenty-five years there are many ways of analysing the data. They looked first across the whole sample of all years and industries. This showed that age is accounting for nearly ninety percent of the changes in satisfaction. I wonder if the customer service mangers know this? They also looked at different years. For example, this is the data across the forty-five industries in 2008.
In this sample year, satisfaction went up in a straight line with age. The pattern is consistent across years. One might think that satisfaction would also be related to education, income, and gender. An analysis looked at the relationship between age and satisfaction for each of the forty five individual industries. This was done over the many years of the survey. In each case it also controlled for all these demographic variables. The same strong relationships existed. In only three industries was there no apparent relationship.
December 2021
Why Are Older Consumers More Satisfied?
Time We Have Left. Carstensen’s idea was that at some point mortality becomes real. Her “socioemotional selectivity theory” says that at that point we start to adjust our behaviour. We do this based on the time we feel we have left. We manage our lives to maximize positive emotional experiences. Life becomes too short to do anything else. The theory is more complex because it suggests that there is not a single point at which our motivation changes. Instead there is a progressive change as our life expectations age. Scales have been developed to measure not only the time we feel we have left, but our aspirations.
If we know that older people manage their experiences to maximize the pleasurable ones. They will have chosen suppliers accordingly. They only go where they are likely to be satisfied. They are less likely to experiment and have a “bad” experience.
They have expectations that have been built up over many years. They have “seen it all before” and there is lots of tolerance for minor variations. They have expert scripts. Because they always "look on the bright side of life" they do not register the mistakes. Just as they look more at happy faces than miserable ones. Even if they do see something that is wrong they may “correct" their memories. We know that memories of older people are more positive than reality. This survey happens annually and relies on those memories. Even if they do not get what they expect, is it worth being dis-satisfied? Most experiences are happening on autopilot. Why create an emotionally upsetting one? For a manager who is bonused on customer satisfaction scores there is a simple plan. Get more Third and Forth Age clients!
December 2021
Consumer Satisfaction Grows with Age.
US Customer Satisfaction across 45 industries in 2008.Expert and Novice Consumers
Not all consumers are equally proficient at playing their role. A service firm must contend with “novices” and “experts”. At any major airport it is easy to spot the regular flyer from the novices. The experts know which queues are quickest at security. They know where the gates are and the quickest way to get them. They are even aware of which seats to take at the gate to be best placed for boarding. Experts will take less time to pass through the airport. they will get a satisfaction from knowing that they are experts.
A novice performer uses more general scripts to handle situations that differ in quite significant ways. For example, using a “dining” script to cover both a “fine dining” and a "family restaurant" experience. Their scripts will tend to be simple and have very few “if-then” branches within them. As a result, a novice is more likely to make mistakes in a specific setting. They are less likely to cope with complex situations.
The expert performer by comparison will have rich and complicated scripts. Having had many experiences of the service they can cope with unexpected changes. and have plenty of “if-then” branches in their script. They have a specific “fine dining” script. They can cope with personnel introducing variations, such as menu items not being available. Ageing consumers are more likely to be experts because of their breadth of experiences.
Following the script successfully can influence satisfaction in several ways. Following the script means that they experience will be good and go according "to plan". This will be satisfying. The consumer will often have a sense of achievement in navigating a service experience. Achievement is known to be a determinant of satisfaction.
The Ageing Actor
A service consumer is not just a processor of multi-sensory input. They are part of the production process. We can think of them as partial employees or as actors in a play. What happens to our ability to follow the script as we grow older? We may not be able to walk to the airport gate. We may not hear the daily specials because of the background noise. We may take longer to check the bill. All this has two knock-on effects. As partial employees we cannot do our job. The operation will slow down and be less efficient. We will be less satisfied with the experience. It may also undermine our self-confidence. Failure to follow the script may reinforce the “old age” stereotype in our heads. It will literally make us feel older.
Ageing will influence satisfaction. The multi-sensory experience may be distorted by changes in the senses. An ageing consumer may not be able to follow the script because of changes in their brain, senses and body. That will affect satisfaction directly and through failures in the production process. Ageing consumers can therefore influence the satisfaction of other people.
June 2021
Consumers as Emotional Actors
The "emotional work” idea has been applied to front line employees in organizational behaviour. (see Research Section). It is now being applied to consumers to extend the idea of a service script. As consumers we are also partial employees, we too must play our part. We must follow the mechanics of the script. We must also become emotional actors. The emotional script may not be consistent with how we feel at that moment. Indeed it may not be compatible with how would normally behave. To the extent that creates a gap it requires us to regulate our emotions just as much as the FLE’s.
Why would we do such a thing? Why would we invest the energy? We may believe that being civil and friendly is the way we want to live our lives. It will reflect on the rest of our day and all our relationships. More cynically we may believe that regulating our emotions will improve the quality of the service we will receive. Displaying anger may ensure that we get what we want. Being friendly to a staff member may make them feel better and help us to get better service. There are many emotions that people will deploy. Often these are not their underlying emotions. It appears that we too can be good or bad actors. We can pretend on the surface or we can internalize the role and engage in deep acting. I suspect that the employees can spot surface consumer acting.
The service setting and the other customers set the standards for the display of emotions. The physical environment always sends signals. The furniture and lighting of a restaurant signals "luxury". This in turn defines the acceptable display of emotions. A lively fun bar on a Friday night sets a different display rule. If everyone is happy, you do not want to be the source of a “dark cloud”.
The Ageing Emotional Actor
Older people have many more experiences to draw upon. They know that the flight delay is outside the control of the person on the gate. They appear to be more satisfied with their service experiences. They can still act anger if they need to. Like the employee they can surface act or they can engage deep acting.
Older consumers are however already regulating their emotions, unlike their younger selves. Under the “life is too short” paradigm they are avoiding negative situations. They are orchestrating positive ones. This must influence their acting strategies. Do they need to “deep act” if they are to reconcile their own agenda with the display rules of the service experience. They may find the display rules more onerous than their younger selves.
June 2022
Consumer Perception
Consumer's Perceptual Completion.
We tend to think of our senses as neutral measurement instruments. Our eyes are thought of as some form of camera that sends pictures to the brain. Our ears are microphones. The senses deliver undistorted reality. Nothing could be further from the truth. Our perception is not reality. We inhabit a personal virtual world created by our brains to maximize our chance of survival.
We blink on average fifteen times a minute. We never experience a moments interruption to our vision. In each eye there is a blind spot where the optical nerve attaches to the retina. In an area a few millimetres across there are no sensors. Even as an infant, we never experience the blind spots. Our brains are making compensatory adjustments.
Our lenses are a masterpiece of evolution. Physicists know that they cannot produce straight and parallel lines across our whole field of vision. Our mind makes sure that buildings do not bulge. When someone wearing a red shirt walks inside from bright sunlight to a room lit artificially, we see no change in colour. The difference in the frequency of the ambient light should change the colour.
The brain compensates for the other senses as well. If we touch a wall with our toe and finger simultaneously the signals cannot reach the brain at the same time. The one from the toe must travel further. This would be extremely confusing; perception merely equalizes the signals. Perception can subtract as well as add. New odours are stronger to us when we first experience them. If we have continued exposure, then the smell “fades into the background”. The first day working on a pig farm is the worst. Repeated exposure means we do not notice any more. Our sense of all other smells meanwhile does not change. The effect reverses if we no longer work in the smell all day. Our sensitivity to that smell increases again. Taking a holiday can make the first day back on the farm unpleasant again.
Sometimes perceptual completion is not so helpful. The latest theories on tinnitus suggest that perceptual completion may be the cause. Tinnitus is a ringing in the ears that affects one in five adults. For some it is a minor distraction, for others a chronic disease. As hearing declines, the brain can be starved of input at certain frequencies. The latest ideas suggest that perceptual completion creates the ringing to complete the sound picture. The ringing is in the brain not the ears.
November 2021
Reality is Just a Guess
To survive in our evolutionary past, we needed to recognize danger. Our brain learned to create the reality we needed. All the senses operate together in real time. The brain is searching for a pattern it recognizes. It iterates through all the senses and its associative memory looking for a fit. Perception is a constructive process. The brain is constructing a mental image that best suits us now. As it starts to get “a fit”, the brain redirects the senses to areas of the “scene” that need to be better defined.
The information received from the senses is always incomplete. Receptors may be faulty, more so as we age. The scene may have interference. A conversation in a crowded room must be distorted by the background noise. Perception starts with what it has and then compares it with an accumulation of memories. It then uses problem solving and inference to find a fit. If that fails, it guesses. Our reality is not real and is just a guess.
Perceptual completion comes to the aid of the Third Age consumer. Our senses fade with age. Not everybody loses a particular sense. Few people suffer deterioration in all senses. There is huge variability across individuals. The thresholds increase for those senses so that we need more stimulus: light, sound etc to react. Despite this perception is able to maintain our “virtual reality” for many years .
The ageing actually helps perception. We have a much greater collection of memories and scripts on which to draw. We have “seen it all before”. This improves the chances of our perception finding a fit in our associative memory. Age brings more experience at categorizing and abstracting. Both of these are essential parts of the pattern recognition process. Age brings with it wisdom. We are able to see patterns that younger people cannot recognize. We are more emotionally stable. We are better at “pattern recognition” in stressful situations. Perception can use all of this to maintain our reality. If necessary, it will guess more. From the age of forty our perception increasingly depends upon our brains and not our senses. We really are in a virtual world of our own.
November 2021
Noisy Guests
Too Much and Too Little Noise for Consumers
Within a restaurant once the noise level rises the Lombard Effect begins. Etienne Lombard discovered it at the turn of the twentieth century. Every species has a need "to be heard". Birds will sing louder or change the frequency of their song. For humans we change our speech in reaction to background noise in a completely involuntary way. Instinctively, we try to make ourselves easier to understand. We are not just egotistically shouting because we believe our words are more important. Just like the birds, we raise the volume and the pitch of our speech. We even extend the duration of our vowels. We exaggerate our facial expressions without knowing we are doing it.
The problem for restaurants is that some level of noise is essential. People want to have a conversation, but do not want to feel that other people are listening. This happens in any setting when there are few guests or customers. A classic example is the early evening in a busy restaurant. Researchers know the answer and it is a concept called Partial Loudness. This states that a sound will appear louder when it occurs in isolation. We will often whisper. We need background noise so our conversations can "get lost" within it. We then feel safe to talk.
A noisy garden bird table may not be a problem. The impact of the Lombard Effect on a restaurant or bar can be dramatic. Each table in turn reacts to the increasing noise from the others. Each tries to complete their conversation, producing a snowball effect. Researchers have tried to find at what level the snowball starts to “roll down the hill picking up snow as it goes”. It seems that noise levels as low as fifty-seven decibels can trigger the “explosion of noise”. This level of background noise was enough to start an individual changing their speech patterns in a recent experiment. This is only slightly above normal conversational sounds.
Making Consumers Wait
Many studies have looked at the simple experience of queuing. They show that the time we perceive we spend waiting varies significantly from reality. One study of queuing asked respondent to estimate how long they waited in a queue at the bank. From security video tapes, it was then possible to measure actual waiting time. The average respondent perceived that they had waited four point seven minutes. The actual time was only three point six minutes. The average overestimate across all wait times was thirty percent. The perceived waiting time is influenced by the rest of the experience. Background music will tend to make waiting seem shorter. It is even influenced by the other customers. Queuing with people who are socially dis-similar will make it seem longer.
Always Look on the Bright Side of Life
Eye tracking studies can measure what people focus on in real time. Researchers have shown that older people look towards happy faces, when shown a selection of happy, sad and neutral pictures. They look away from negative faces much more than their young counterparts. Far more of what an older person remembers is positive. Pictures of three types were shown to different age groups of people. Some pictures were positive, others neutral and the third group emotionally upsetting. The older people were, the more they remembered the positive images. The older they were, the less they remembered the negative ones. Gender, ethnicity, and socioeconomic level did not affect the relationship.
In another study, older and younger adults selected information to examine health choices. They did this by clicking on cues. They also indicated whether they saw the information as positive, neutral, or negative. As predicted, older adults remembered a much higher percentage of the positive information. Older adults are more likely to request, and process information presented in a positive way. This is preferred to a negative presentation. Perhaps advertising agencies should remember this when developing charity campaigns. Showing pictures of victims to older donors may not be the best strategy. Those same donors are often the best givers.
Not only do we only remember positive things when we get older, but we will “re-write history” to make it positive. We remember good decisions and suppress poor ones. Older adults will also distort their memories of past health issues. They will remember them as more positive than they were.
December 2021
Life is Too Short
Laura Carstensen was working at Stanford University. She witnessed the impact of HIV on the San Francisco homosexual community. She saw many young men whose lives were being tragically shortened. She wondered whether their motivations were the same as older people. Both were facing death. She found it was the case. She formulated her “socio-emotional selectivity theory” as an explanation.
Basically she argued that “Life becomes Too Short” to deal with negative experiences and the emotions that they cause. Instead we seek emotional experiences that are more predictable and likely to be positive. We consciously avoid encounters with others that we predict will cause feelings of sadness, fear, or anger. The theory goes on to suggest that a shorter time horizon focuses us more on the present. Our emphasis becomes what can be experienced and enjoyed now.
Older people focus on their own emotional wellbeing more. They allocate their time differently. They try to control or regulate their emotional experiences. They seek positive and pleasurable events. They minimize the risk of negative emotions. They will actively avoid potentially negative situations.
December 2021
Felt or Cognitive Age
Older Consumers Always Feel Younger than their Age
Beyond the age of twenty-five, if we are asked “How old do you feel?” we invariably give a younger age than our chronological age. Third Age consumers across the world feel younger than their actual age. How much younger varies not only by chronological age but by country. The Danes of a given age feel younger than comparable Americans.
The data for Denmark is typical of most countries. At all ages over forty, less than five percent of people say they feel older than their birth certificate age. (Until the very end of their lives). There is a constant group of around thirty percent who feel their age. The balance, of close to seventy percent, claim to feel younger. They feel on average, twenty percent younger. A seventy-year-old in this group on average feels fifty-six years old and an eighty-year-old, sixty-four. The overall average is the mix of the three groups: feel older; feel your age and feel younger. Across all Danes a seventy-year-old feels only fifty-nine. There are huge variations across individuals.
December 2021
Our Bodies may be on Earth but our Heads are on Mars
As our chronological age increases so does the age we feel. However, our chronological age and the age in our heads do not increase at the same rate. Our heads are on Mars time. It takes Mars six hundred and eighty-six days to circle the sun, so time goes more slowly. Ten years on earth would feel like five point four years on Mars. How old we feel increases approximately five point four years for every chronological decade. The average seventy-year-old may feel sixty. In the ten years it takes them to reach eighty, they will only change the age that they feel to just over sixty five.
Feeling younger is not just a “nice to have”. "Felt age” is a better predictor of the onset of many psychological and physiological diseases than your birth certificate age. It is however a two-way street and an illness can often make people feel older. Feeling older than your age is correlated negatively with life expectancy.
December 2021
The Ageing Senses
Consumers Don't Notice Sensory Loss
Self-awareness of the sensory loss is low. It is an extremely poor predictor of the actual state of our senses. In a fifty-five-year-old age group of women with proven clinical decline in their sense of smell, only one third said they had a problem. This dropped to twelve percent for the above eighty age group. The gap gets bigger as we get older. Because of Perceptual Completion it seems that our memories are increasingly driving our perceptions.
According to medical science the amount of light falling on my retina is less than half of someone half my age. Despite this I do not perceive myself walking around in the dark. My brain can fill in most gaps. Unfortunately, not all of them. I still cannot read the menu in a darkened restaurant. The input my eyes can provide, even with glasses on is too low. Perhaps it is the brain that is no longer powerful enough to even make a guess?
Certainly, older people complain more and more about distraction. They complain about the noise is bars and restaurants. “I cannot hear myself think”. This may be truer than they think. Coping with distraction requires “multi-tasking”. We must filter the noise out whilst studying the menu and deciding what to eat. With age multi-tasking becomes more difficult. Is it easier to overwhelm the brain with too complex environment full of multiple stimuli.
Taste and Smell
Service experiences are clearly multi-sensory at a conscious and sub-conscious level. We use every sense to interpret the world around us. What happens when our senses age? In general, we know that thresholds rise. We need more light, taste, scent, touch to register in our senses.
A US study showed that a quarter of the population over 50 had a problem with their sense of smell. The study used a simple smell recognition test for 8 smells found in the home e.g., chocolate. A "problem with smell", was defined as the ability to identify only 6 or less smells. There was not a straight-line relationship with age. Smells can be correctly identified until our seventies. Only about a fifth of Third Agers had problems. This grew to sixty percent with the start of the Fourth Age.
The sense of taste declines with age as well. Our taste buds and smell receptors have a remarkable capacity to regenerate themselves. The taste cells within the taste buds have an average lifespan of eight to twelve days. Our mouth is continuously regenerating them. As anyone who has burned their mouth on hot food will testify. It does not take long for the sense of taste to regenerate. As we age the regeneration process slows and eventually stops, leading to a decline in the number of buds.
The sense of taste starts to deteriorate earlier than smell. It can start to decline in one’s forties and fifties for women and fifties and sixties for men. Of all the tastes, sweetness lasts the longest. Ninety percent of the Third and Fourth Agers still recognizing it. For many people ageing healthily, means taking one or more medications. Modern medicine can allow us to live an otherwise normal life, even with high cholesterol, blood pressure, diabetes etc. There is however a hidden cost. These very same drugs can reduce our sense of smell and taste, often significantly. This accelerates the impact of age.
The service experience is multi-sensory. It is conscious and sub-conscious. We can show the impact of the different senses separately. However, we seem to integrate all our senses when deciding whether to be satisfied. Many of the sub-conscious reactions are associative. We learn associations between a smell or a colour and good or bad emotions or outcomes. We associate a gold colour with quality, or a touch with mothers comfort.
Ageing Hearing
With age all our senses reduce in sensitivity. The threshold of detection rises. We need more light, sound, smell etc to "drive" our senses. With hearing however there is an extra problem. As we age, we progressively lose higher frequencies. This is a particularly acute problem for men. The diagram below is an audiogram showing the impact of age on hearing.
The audiogram shows frequencies along the horizontal axis. These range from the “bass” noise of a truck on the left to the high frequency sound of birdsong on the right. The vertical axis describes the noise levels from the quiet rustling of fallen leaves to the intense sounds of a rock band or airplane. This Audiogram shows commonly occurring sounds.
The sound level of a quiet room or a whisper would register about twenty decibels, a normal conversation is about forty five. A television in a normal sized room might generate sixty to eighty decibels. Standing ten metres from a major road would generate sound levels of eighty or ninety. Above that, sound can be more painful and indeed can harm your ears. A pneumatic drill is about one hundred and twenty decibels.
The impact of age is clear for those people who develop this kind of hearing problem. Below 1000Hz we can see the impact of age on sensitivity. We need more sound energy to drive our hearing. A normal healthy young individual will have thresholds between zero and twenty decibels across all frequencies. This is the quietest sounds they can hear at that frequency. As we age those thresholds rise. There is 2.5Db decrease in hearing sensitivity per decade up to 55 and an 8.5Db decline per decade after that. Above 1000Hz age also means a steep drop in high frequency sensitivity for many people. For a seventy-year-old sufferer this can mean a loss of birdsong and an inability to hear whispering.
It can also detract from our ability to understand speech. The banana shaped envelope on the Audiogram covers the spoken word at normal levels. There is an interesting variation in both intensity and frequency of different parts of speech. Certain sounds are quiet and high frequency (“f”, “s” and “th”). These sounds can be lost as we age and lose higher frequencies and sensitivity. Others are lower frequency and/or noisier.
April 2021
Hearing Loss Relative to Familiar Sounds.
The Ageing Body
Activity and Exercise
The body and the mind are not separate. We like to separate these ideas but operationally they are one. The biggest single determinant of cognitive ability is the body. It provides the oxygen needed to “feed” the brain. Adults between the ages of 60 and 80, can increase the size of their brains by regular aerobic exercise. Amongst other benefits their frontal cortex grows. The best way to learn something new is to engage in physical activity before starting. The body can directly influence our cognitive capacity.
Humans were not made to sit around. The brain and body evolved to move us around. To take us away from danger. To take us to sources of food and to help us find mates. The brains job is to organize that movement. Certainly it needs oxygenated blood. The fitter we are the more oxygen our bodies can provide. But it also needs to be stimulated with the tasks for which it was created. It needs new and different environments to explore. It can be a walk that engages all the senses and all the problem solving capabilities of the brain. The walk can in be in a country lane or a complex department store or mall. Such explorations have two beneficial effects. The exercise improves our ability to send oxygen to the brain. It also provides the kind of activity needed to stimulate the brain that going to the gym will not.
The Ageing Clock: Early Birds and Night Owls
Chronotypes
The Hadza tribe live in the isolated areas of Northern Tanzania. They are hunter gathers. They have never adopted the “modern” idea of farming. They are living a life that characterized the whole of humanity at one time. They are window into our evolutionary past.
The Hadza operate in groups of 20 or 30. The group is mutually supportive in the hunting and gathering needed for their survival. Anthropologists have studied the sleep pattern of a group of Hazda. They used modern activity trackers to assess when the different members of the group were awake or sleeping. Over a twenty day period they found only eighteen minutes when the whole tribe was asleep. At any point of the day or night about a quarter of the tribe was awake.
The “sentinel hypothesis” points out that we are at our most vulnerable when asleep. When we all lived like the Hazda we needed to have guards or sentinels. They had to be able to stay awake at any time that people were asleep. Evolution thus created different chronotypes. People who are awake and active at different times and sleep at different times. We needed both “night owls” and “early birds” if we were to survive as a species.
Early Birds and Night Owls
People have different alertness / drowsiness rhythms. The early birds will have their peak alertness in the first five hours of their day. The Night Owl by comparison hates the morning. Their peak alertness time will be in the evening. This is not folklore. Scientists have been able to show a variation in everything from body temperature to melatonin production. There is in a spectrum of chronotypes. Each has a different rhythm.
We all might instinctively know our chronotype. For one group, knowing exactly when they are at their peak performance is crucial. Professional athletes want to be at their best at the time of the race or the game. Sports scientists do a lot of work on athletes, soccer players, basketball players etc. They need to understand when particular people will peak and the impact that has. Being at peak can improve performance by 2 seconds in a fifteen hundred metre race. It can cut seventy five seconds off a marathon time. That may not seem much but in the latest London Marathon that seventy five seconds was the difference between being 1st and 4th for men and 5th for women.
The Ageing Clock: The Master Clock
Within our hypothalamus there are twenty thousand neurons which oscillate and are our master clock. This area of the brain is called the suprachiasmatic nucleus or SCN. Global standards of time are set by atomic clocks which keep time accurately over hundreds of years. They are carefully isolated from their environments. The SCN by comparison is continuously updating itself using outside stimuli. It is sensitive to light-dark cycles. It also adapts to our behaviour for example the time at which we eat.
The SCN controls peripheral oscillators that govern everything the body does. We have a clock for digestion and another one for sleeping and waking. We have clocks for core body temperature and hunger. There is even a clock for alertness. Part of the role of the SCN is to manage the alignment of the clocks.
The Ageing Clock
As we age the SCN is less effective at time keeping. The white matter or myelin that coats the interconnections between the neurons declines. So too does the production of neurochemicals. Two things happen. Older people are more likely to be morning people or “early birds”. Their clocks are moved forward by four or even six hours. After the age of sixty alertness and performance swings at different times of the day are bigger. Tested in the morning the sixty year old will perform the same as a forty or fifty year on most mental ability tests. They are as good at solving problems and their memory is strong. They are as good at reasoning and fine motor skills. Testing the same people in the evening or late afternoon and their performance drops compared to the forty to fifty year. By the age of seventy the differences are even greater.
The Aeon Mall in Tokyo is designed to serve the over 65’s. Interestingly it opens two hours earlier than most Malls. It opens at 7.00am and by 7.30 on most days is buzzing. The have special “golden hour” deals in many outlets. These are only available between 8am and 9am. They seem to know all about the ageing of the chronotypes.
It is important to make decisions in the morning if they are crucial. If you are crossing time zones there is even more to worry about. Our biological clock is much more flexible when we are young. It can adapt to changes in time zone more easily. Older people are more susceptible to jet lag. More specifically it takes them longer to recover. There is normal rule of thumb to ensure good decision making. You must allow one day to recover for each one hour time difference when travelling East. Coming home and flying West the same one hour time difference needs only half a day for recovery. As we get older resetting the clock takes longer. Older people are particularly susceptible to having to wake up earlier and go to bed earlier. Everything takes longer, sometimes much longer when travelling West.
The circadian rhythm means that most people have two energy dips a day. The first is in the middle of the night. The second is between one and three in the afternoon. As we age the post lunch dip in energy is a lot more noticeable. An afternoon nap is not a luxury but a necessity. All the more reason to make the important decisions in the morning.
Fixing the Clock to Sleep Well
Maintaining the stability of the SCN is important, especially with age. Older people need as much sleep as their younger selves. In many cases they just cannot get it and suffer disturbed nights. The arrival of artificial lighting changed forever the normal rhythms that the SCN used. Bright lights before bed are bad. It is even worse if the light is blue. We have more blue receptors in our retina than any other type. Somehow bright blue lights can disturb our normal rhythm and stop us sleeping well. Computers and smartphones before bedtime will upset everyone’s sleep. The Third Agers will have an especial problem.
The SCN reacts to our behaviours. It expects us to go to sleep at a certain time. If we want to sleep well, we had better do what it expects. A regular routine of going to bed and getting up helps us sleep. Eating also signals the SCN. If we eat within two hours of going to bed we create a disconnect between the SCN and the clocks in our stomach and intestines.