magazine for alumni and friends of Massey University.
Issue 14, April 2002
Professor Philippa Gander and the Sleep/Wake Research Centre
Tired, listless, crabby? So who isn’t? New Zealanders,
like most of the civilised world, are chronically sleep-deprived,
an affliction that probably owes much to the light switch.
Most species on this planet have some kind of internal time-keeping
system that keeps them functioning in step with the day/night
cycle, and this is known as the circadian clock. We don’t
function the same way physiologically or psychologically across
the 24-hour period. Your brain is programmed to be asleep at
night so it functions quite differently from during the day,” explains
sleep expert Professor Philippa Gander.
“ Up until the industrial revolution and the widespread availability
of artificial light, people largely slept during the night
and were awake during the day. Now more and more of us are
trying to work against that.”
When Gander and the Sleep/Wake Centre surveyed 10,000 adults
drawn at random from the electoral roll, 37 percent said they
rarely or never got enough sleep. Another Centre survey, this
one of insomnia, found 29 percent of Mäori and 25 percent
of non-Mäori reported having a chronic sleep problem.
We know experimentally that if you deprive people of sleep,
even only a few hours a night, you certainly change their waking
function. They are sleepy. They tend to be more irritable.
They are slowing progressively in terms of their reaction time,
in terms of their cognitive processing, in terms of their psychomotor
coordination,” says Gander.
Sleepy, irritable, slow. It has just turned 10. I monitor my
own cognitive processing, reaction times, and psychomotor coordination
and reach for the coffee. Philippa Gander has very brown eyes,
a direct gaze, a mirth that sometimes tugs at one corner of
her mouth, and she is very, very awake.
is the word Gander applies to her career. In her first year
at Auckland University the former Rotorua Girls’ High
School pupil had hit on molecular biology as her future; in
her second she was waylaid by a zoology course in ‘social
behaviour and timing’. The course was fascinating, the
teacher – later her supervisor– exceptional. “I
decided I was much more interested in biological rhythms and
Her Master’s thesis examined circadian rhythms in wetas.
Sometimes referred to as invertebrate mice after the ecological
niche they occupy, wetas indeed turned out to have similar
circadian clocks to rodents. Gander also mathematically modelled
how the clock mechanism might work at the cellular level. “People
were very familiar with cellular oscillation, but no one could
imagine how an oscillation took place over 24 hours; how, with
the mechanics of a cell, you could generate a 24-hour periodicity.” The
model she worked on looked at “diffusion processes and
synthesis in the nucleus, delayed feedback, those kinds of
things in very general terms”. It would later reveal
itself as remarkably accurate.
For her Doctorate she turned to the kiore, or Polynesian rat.
Every year the kiore (Rattus exulans) of Tiritirimatangi Island
began breeding over the same two-week period. Her zoological
colleagues thought this might have to do with seedfall. Gander,
who looked at the breeding patterns of kiore in their whole
range, decided it had to do with day length “because
they have a nice latitudinal cline in their breeding season”.
In the laboratory she confirmed her suspicions by taking juvenile
females and exposing them to different lengths of light cycle
to bring them into oestrus or set their activity patterns.
It was with a year still to go on her PhD that Gander was made
aware of an ad in Science for a job at Harvard, looking at
the neuroanatomy of the circadian system in mammals, particularly
primates. It was, she says “the dream job so far as I
was concerned”. And Harvard must have liked her too,
for they held the job for her until her graduation in 1980. “I
got a Fulbright Fellowship in the interim, so I was a Fulbright
Fellow at Harvard. I was working on neuroanatomy and the behavioural
side of the circadian system in monkeys but also doing mathematical
modelling of the human circadian system.”
Gander was shoulder-tapped by NASA to join their Fatigue Countermeasures
Programme. In the early 1980s Congress had
instructed NASA to look at the safety issue of fatigue in aviation.
Circadian rhythms and their role in pilot functioning were
to be key. “And that was fun, that was just amazing.” Gander
became involved in a series of big field studies “which
will probably never be repeated”. Hundreds of pilots
were enlisted. They wore physiological monitors 24 hours a
day: their heart rates were monitored continuously; they wore
rectal probes to measure body temperature, and watches that
monitored body movement to see when and how they slept; they
maintained log books into which they self-rated their moods
and fatigue every two hours. “It was very intensive stuff,” says
Here then is a sleep primer: some of the things that you, as
someone who spends a third of their life in the activity, owe
it to yourself to know. There are two kinds of sleep, rapid
eye movement and non-rapid eye movement sleep. The two types
cycle throughout your night’s sleep. REM sleep is accompanied
by fast brain activity, eye movements and a lack of muscle
activities. If you
are woken from REM sleep you will very likely remember dreaming.
If you are woken from a deep non-REM sleep you may
find yourself disoriented and groggy.
Sleep is necessary. Try to fight it off for long enough and
the body will eventually have its way and you will fall asleep
When you find it easiest to sleep, and the type of sleep you
will have, is dictated by your circadian clock. You are likely
to be sleepiest at around 3:00 to 5:00 am and then again at
The circadian clock also affects other things. If you want
to play chess, do it around noon. This is when your ability
to solve complex problems or conduct logical reasoning is best.
Play that game of badminton in the early evening when your
physical coordination is best. Your short term memory is best
in the morning; long-term in the afternoon.
Resetting the circadian clock is not – as any jetlagged-and-sleepless
traveller will tell you – a matter of waiting for the
time pips and pressing a button. The circadian clock is reset
via a complex set of cues, including sunlight, work, rest
and social contact. Due to conflicting cues, night shift
hardly ever completely adapt their circadian clocks.
If you have accumulated a sleep debt over a series of nights,
you will usually need two nights of unrestricted sleep to
return to normal.
In the mid 1990s, having worked off and on for NASA throughout
the 1980s, with time out to live in France and have two children,
Gander decided to return to New Zealand.
When she began her career back in the 1970s the cells in
the human brain which control the circadian clock had only
been discovered. Now sleep was becoming well understood and
from the early 1990s NASA’s attention had increasingly
turned to putting what had been learned into good practice
and public education programmes.
founded the Sleep/Wake Centre in 1998 as part of the Wellington
School of Medicine. She knew the relocation meant
trade-offs: research budgets she would
never see the like of again, against lifestyle and New Zealand’s attributes
such as “a nice little laboratory”.
For with just four million people New Zealand has its advantages. Here it is
feasible to do random surveys of the entire population in a way that would
never be possible in the US. In the recent survey canvassing 10,000 people,
Centre and the Eru Pomare Mäori Health Research Centre had more than 7000
responses, “which is fabulous,” says Gander. “New Zealanders
are interested in sleep. It really is great to be working in this country and
to be working on sleep.”
The Sleep/Wake Centre is unusual in oversampling the Mäori population so
that the sample sizes of Mäori and non-Mäori are the same. This allows
statistically meaningful comparisons to be made between the two populations and,
together with the use of an index of deprivation – a map of New Zealand
broken into small units (around 90 people) rated in terms of domains of relative
deprivation derived from census data – has allowed the Centre to look
simultaneously at the effects of social and economic deprivation and ethnicity
on the prevalence
of sleep disorders.
New Zealand, which has a tradition of being something of a social laboratory
for the world, is also somewhere the Centre’s scientific findings can be
put into practice. “On our legislative and regulatory fronts people are
experimenting with schemes that haven’t been tried in other countries,” explains
In transportation and aviation we have been moving away from the idea of prescriptive
rules,” says Gander. “Instead there is greater emphasis being placed
on fatigue management.” Fatigue is a major public safety issue. The Chernobyl
meltdown, the Three Mile Island incident, the Bhopal cyanide gas catastrophe,
the Exxon Valdez oil spill:
lack of sleep has been implicated in them all.
Remember the 37 percent of New Zealanders who report rarely or never getting
enough sleep? Another revealing percentage: there is a 33 percent increased likelihood
that someone in that 37 percent has had a vehicle accident in the last three
among the groups of shiftworkers that have drawn the attention of the Centre’s research are those whose roles have wider public safety implications.
The Centre and its postgraduate students have looked at the effect of short naps
on the functioning of air traffic controllers (they proved an effective way of
improving functioning) and at the sleep-wake patterns and functioning of anaesthetists.
A nationwide survey of hours of work for junior doctors is in the offing. “We’ve
just had funding from the Health Research Council – the first big grant
we will work on with Massey,” says Gander.
And on the roads? Although sleepiness is highly likely to be a contributing
cause in many road accidents, pinning the blame is difficult. “If you are looking
for whether fatigue or sleepiness was involved in an accident, it’s very
hard to tell,” says Gander.
Unlike for alcohol, there is no blow-in-the-bag test for fatigue and sleep
You really have to reconstruct the person’s sleep history and the time
of day and various other things to construct the case whether or not their
function was impaired.” Usually, says Gander, the role of fatigue is
recognised only by default. “People
can be extremely activated after an accident or else they are injured, so how
can you tell if they were fatigued]? So often it is by a process of elimination.
There was no other vehicle involved, there was no vehicle fault, no alcohol,
drove off the road or into a bridge, then you assume they weren’t controlling
the vehicle and they might have been asleep. “
We are trying to move beyond this.”
For over a year Commercial Vehicle Investigation Unit police officers have
been giving drivers involved in truck crashes a questionnaire about their sleep. “
That comes back to us and we then match that up with the crash report from
the LTSA database to see what percentage of the crashes we think involve fatigue.” Fatigue management research and education contracts have come to the Centre
from the likes of BP, Boeing and Tranz Rail.
If sleeplessness is a national affliction, then what is being done about sleep
disorders? According to Gander and most sleep experts, not nearly enough.
Often sleep disorders go undiagnosed. When they are spotted the treatment is
often a GP’s prescription for sleeping pills, and there are too few treatment
facilities. Gander argues that our treatment of sleep disorders should be more
systematic, as it is in countries like America and Japan, where the prevalence
of sleep disorders is similar to our own. (One of the Centre’s current
PhD students has taken as her topic a systematic approach to the recognition,
diagnosis and treatment of sleep disorders in New Zealand.)
The Centre is working with the Eru Pomare Mäori Health Research Centre and
the WellSleep Clinic to investigate the causes, prevalence and treatment of sleep
disorders in New Zealand.
Sleep apnoea, a condition in which people stop breathing when they fall asleep
and must wake to breathe, has come in for particular attention. Particularly
common among Mäori, the condition is associated with high blood pressure,
heart disease and stroke. Often the sufferers are oblivious to their condition,
even though they will have experienced fragmented sleep and daytime sleepiness
as a result. (Usually it is their bed partners who will have noticed the symptomatic
breathing pauses, snorts, snores and gasps.) The Sleep/Wake Centre is working
on a questionnaire and an accompanying index that can be used by GPs to predict
which patients are likely to have sleep apnoea and should be referred for treatment.
As for the open-all-hours society, Gander has mixed feelings about it. “Apart
from the emergency services, the reasons for going to 24-hour service are to
improve productivity and profitability. But if there is a consequence in terms
of the health and well-being of the workforce, if their health fails or their
marriage breaks down, then it seems to me that there is a cost being passed on
to workers, their families and ultimately the community. So are we doing a cost
transfer? I think there should be a debate. I am not saying that all 24-hour
work is evil and dangerous. It certainly isn’t, but we need to think about
the consequences.” MASSEY looks forward to reviewing Philippa Gander’s
forthcoming book Sleep and the 24-Hour Society published by Open Mind Publishing,
A timeless place
If you want to find out what a person’s
natural circadian rhythm is, there is only one way: remove
all outside cues.
So sunlight will never enter the three bedroom constant environment
facility being built for the Sleep/Wake Centre, and the temperature
and humidity will never change.
During their stay in the facility, guests will enjoy unlimited
bed rest – sleeping is forbidden, sitting up is allowed – and
servings of a nutritional solution at equal time intervals.
A stay will usually be either 36 or 48 hours: enough to incorporate
a complete circadian clock cycle. Meanwhile such things as
core body temperatures, brain patterns, and the evening rise
in melatonin will be monitored continuously.
One of the first planned uses of the facility will be to
investigate the genetic variability in the circadian clock
and its effects on sleep timing.
In the last few years the clock genes have been discovered,” says
Gander. “There are a few families reported whose members
all have extremely early or extremely late sleep times. They
seem to have mutations in specific clock genes.”
The investigation will begin with a survey that will screen for people who report
extremely late and extremely early sleep times. Then, to check how these reported
times correlate with their circadian clocks, some of the respondents will be
asked to spend time in the controlled environment facility.
Gander hopes the survey will provide some explanation for why some people withstand
the stresses of shift work better than others. It may well be that there are
some people genetically better suited to particular shifts.
Teenage sleeping patterns
“The damned kid stays up all night then spends all weekend sleeping.” The
imprecation, or some version of it, must often be on the lips of the parents
of teenagers. Now, according to Gander, science is providing – in some
cases – an excuse note.
There is some evidence that the circadian clock slips, or that sleep slips until
a later time in the day, and it’s biological; it’s not just oppositional
behaviour,” she says.
“ That delayed sleep phase is relatively common in people in their late
teens and early twenties, and then it seems to rectify.”
Biology is not the sole explanation. The sleeping patterns of adolescents are
a tangle of developmental, physiological, social and cultural factors, according
And you shouldn’t entirely dismiss your unease if your child is up until
the small hours night after night.
At the extreme end, delayed sleep becomes a recognised sleep disorder where they
can’t go to sleep until two or three in the morning. If they have to get
up and go to school then they end up being chronically sleep deprived,” says
Gander. She then follows with a caution: “But if they truly do have delayed
sleep phase and you make them go to bed at 10 o’clock and they can’t
go to sleep until 1 o’clock then you can end up giving them sleep onset
For her Masterate in Public Health thesis, Brigid Wilson has devised a questionnaire
to untangle the factors that influence the sleeping patterns of New Zealand
teenagers. The pupils of Wellington High School were enlisted to help. A repurposed
would not do. “Apart from the language sounding totally wacky, it doesn’t
address the issues in their environment,” says Gander.
One issue that has eluded US surveys is the use of energy drinks. “Yet
here they are one of the most important coping mechanisms for the older teenagers.”
The questionnaire looks at cultural, biological and belief issues, matters that
may one day find themselves in a sleep module in the science or health curriculum.
In preparation for the survey’s national use, a test run at Wellington
High has already produced some interesting results. These show that as the students
get older the gap between the time they spend sleeping during the week and on
weekends grows and the sleep timing gets later. They also show that the students
who lose sleep on school nights are more likely to have their own bedroom and
more likely to have a TV, computer or games console there. “So there might
be quite practical measures to deal with lack of sleep,” observes Gander.
Developmental changes are going on in sleep across puberty and there is evidence
from the US that kids who are chronically sleepy are more likely to be involved
in drugs and alcohol and probably road accidents.
And what should parents do about those slothful weekends? “Letting them
sleep in on weekends is very important. If they don’t catch up on weekends,
then when will they catch up?”