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Psychological effects of polar expeditions
Lawrence A Palinkas, Peter Suedfeld
Polar expeditions include treks and stays at summer camps or year-round research stations. People on such expeditions
generally undergo psychological changes resulting from exposure to long periods of isolation and confinement, and
the extreme physical environment. Symptoms include disturbed sleep, impaired cognitive ability, negative affect, and
interpersonal tension and conflict. Seasonal occurrence of these symptoms suggests the existence of three overlapping
syndromes: the winter-over syndrome, the polar T3 syndrome, and subsyndromal seasonal affective disorder. About
5% of people on expeditions meet DSM-IV or ICD criteria for psychiatric disorders. However, they also experience
positive or so-called salutogenic outcomes resulting from successfully coping with stress and enhanced self-sufficiency,
improved health, and personal growth. Prevention of pathogenic psychological outcomes is best accomplished by
psychological and psychiatric screening procedures to select out unsuitable candidates, and by providing access to
psychological support, including telephone counselling. Promotion of salutogenic experiences is best accomplished
by screening for suitable personality traits, and training participants in individual coping strategies, group interaction,
and team leadership.
The history of polar exploration consists of many tales of
heroism, bravery, self-sacrifice, and conquest. It also has
many tales of hardship, suffering, illness, and death.
Although polar explorations were historically an activity
for the purposes of economic gain, national pride,
scientific discovery, or individual fame and recognition,
they have now become much safer and more common-
place than before. Cruise ships laden with tourists are
regular visitors to the Antarctic peninsula, Spitzbergen
(Norway), and Greenland. Exploration for oil and
subsequent development has contributed to an increase
in the non-native population of the Arctic regions. Studies
of global warming suggest that a year-round ice-free route
across the Arctic ocean could become a reality in the near
future, which could possibly lead to increased numbers of
people travelling these waters for commercial, scientific,
and recreational purposes.1
Nevertheless, apart from anecdotal reports of polar
madness and cabin fever, little is known about the
psychological demands people on polar expeditions face
from the harsh physical and social environment. An
understanding of these demands is of great importance for
prevention and treatment of morbidity and mortality related
to poor psychosocial and neurobehavioural adaptation to
this extreme and unusual environment. Polar expeditions
also serve as a useful analogue to the psychological demands
likely to be faced by people on long-duration space
voyages.2–4
The heroic age
Other than the exploration and settlement of Greenland
by the Vikings in the 9th century, the first recorded polar
expeditions were the three voyages of Martin Frobisher
who sought the Northwest Passage in 1576–78. However,
the heroic age of polar exploration really began with
voyages to the Arctic and Antarctic in the early 19th century.
Accounts of expeditions throughout the 19th and early
20th centuries rarely mentioned episodes of psychiatric
disturbance or interpersonal conflict, as such was not in
keeping with the image of polar explorers, who were
expected to have specific qualities and characteristics,
such as strength and resilience.5 Nevertheless, equally
rare was the polar expedition that did not have at least one
member who was debilitated by depression, anxiety,
paranoia, alcoholism, or sleep disorders. During Sir
Douglas Mawson’s second Antarctic expedition (1910–14),
that person was Sydney Jeffryes, the radio operator, whom
Mawson believed “surely must be going off his base.
During the day he sleeps badly, gets up for dinner looking
bad, husky; mutters sitting on his bunk in the dark
afterward.”6
Frequently, the entire crew of a polar expedition would
experience melancholy and depression, as was the case
of the Belgica expedition to Antarctica in 1898–99. As
described by the great polar explorer and expedition
physician, Frederick A Cook, “The curtain of blackness
which has fallen over the outer world of icy desolation
has descended upon the inner world of our souls. Around
Lancet 2007; 369:
School of Social Work,
University of Southern
California, Los Angeles, CA
90089, USA
(Prof L A Palinkas PhD); and
Department of Psychology,
University of British Columbia,
Vancouver, BC V6T 1Z4, Canada
(Prof P Suedfeld PhD)
Correspondence to:
Lawrence A Palinkas, School of
Social Work, University of
Southern California, Los Angeles,
CA 90089, USA
palinkas@usc.edu
Search strategy and selection criteria
We searched for references listed in PsycINFO and PubMed
(Jan 1975–Nov 2005), with the search terms “polar regions”,
“polar expeditions”, ”Arctic”, “Antarctic”, in combination with
the terms “behavior”, “performance”, and “mental health”.
We also searched reference lists of articles identified by this
search and selected those describing original research that
included a specific focus on psychological or social
dimensions of behaviour, performance, stress, and coping.
The quality of the research described in these articles varied,
from well-designed observational studies and randomised
controlled trials of large groups of residents of polar research
stations obtained over several years, to retrospective study of
a single polar trek of two or three individuals using data
collection techniques with poor reliability and validity. In each
instance, the strengths and weaknesses of the research
methodology was factored into our assessment of the
usefulness of information derived from the study. Several
review articles, book chapters, and earlier key publications
known to us were also included.
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the tables, in the laboratory, and in the forecastle, men
are sitting about sad and dejected, lost in dreams of
melancholy from which, now and then, one arouses with
an empty attempt at enthusiasm.”7 Cook tried to treat
these symptoms by having crew members sit in front of
large blazing fires. This baking treatment, as he called it,
could be the first recorded attempt to use light therapy to
treat symptoms of winter depression or seasonal affective
disorder.8 Other expeditions, such as the Greely expedition
of 1881–84, met a far worse fate than the Belgica
exploration. In their attempt to establish a scientific base
on Ellsmere Island in the Arctic, the crew of the Greely
expedition was driven to mutiny, madness, suicide, and
cannibalism, leaving six survivors of a crew of 25 men.9
No systematic attempt was made to understand and
prevent these behaviours until the late 1950’s. These
efforts were precipitated in Antarctica by a case of
schizoaffective disorder at one station,10 and widespread
interpersonal conflict precipitated by poor leadership at
another11 during the International Geophysical
Year (1957–58). These studies assessed the risk of
psychological disturbances in people undertaking polar
expeditions, and tried to identify interventions for their
prevention, accounting for the logistical difficulty of
treatment or evacuation of people who exhibit such
disturbances. Gunderson,12 for instance, documented a
three times increased risk of psychiatric disorders in US
Navy personnel in Antarctica. Early studies by investigators
such as Rivolier,3 Law,13 Mullin,14 Nardini and colleagues,10
and Palmai15 identified several risk factors rooted in
sociodemographic characteristics such as age, education,
and occupational status, and in personality traits such as
extraversion and neuroticism. Subsequent investigations
by Taylor16 and Natani and Shurley17 focused on the
interpersonal dimension of psychological disturbances.
Present day polar expeditions
Three main types of polar expeditions take place today,
and they entail a range of exposures to cold, danger,
deprivation, and physical demands. The first type is the
modern-day equivalent of the polar trek of the heroic era.
Usually done in spring or summer months when weather
conditions are most favourable, these expeditions are
intended to recreate the experiences of the early polar
explorers, or set new records for speed and distance.
Other reasons for treks include drawing attention to the
plight of Native peoples separated by the Cold War, such
as the Bering Bridge Expedition in 1989, or to the effects
of global warming on Native populations and polar bears,
and transport of supplies and equipment to remote
locations. Although some expeditions use traditional
modes of travel (eg, sled dogs, skis, snowshoes), others
use modern methods of transport (eg, snowmobiles,
tractors, tracked vehicles). Ocean voyages in small sailing
craft are also included in this category. Polar treks are
usually the most challenging type of polar expedition
because the team size is small, they entail the greatest
exposure to the elements, the least access to the comforts
of civilisation, and the highest physical demands.
The second type of expedition is the summer camp.
Such camps are usually for scientific (eg, glaciology,
geology, marine biology) or commercial (eg, mineral or
oil exploration) purposes. Camps range in size from
three to 300 individuals who reside in tents, Quonset
huts, or other temporary shelters. This category includes
ocean voyages in large scientific research or commercial
exploration vessels. The duration of such expeditions
ranges from 2 weeks to 3 months.
The third type of expedition is a period at a polar
research station. In Antarctica, for example, 20 nations
operate 47 permanent stations for the entire year. The
population of these stations in the summer months
(October–February) ranges from 14 to 1100 men and
women, and from 10 to 250 during the winter months
(March–September). Most of these residents are aged
between 18 and 60 years. In the Arctic, comparable
stations exist and are operated by the nations that border
the circumpolar north (USA, Canada, Russia, Iceland,
Sweden, and Norway). People on these expeditions are
usually researchers in disciplines such as marine biology,
astronomy, upper-atmosphere physics, meteorology,
seismology, geology, and glaciology. Most of their time is
spent indoors, especially in winter, and they usually have
all the conveniences of modern life, including warm
shelter, good food, communications with the outside
world, and opportunities for leisure activity.
Expedition stressors
Irrespective of the type of expedition, people face many
stressors from the physical and psychosocial environment
of high latitudes. These stressors were aptly summarised
in Mear and Swan’s18 account of the Footsteps of Scott
expedition in the Antarctic: “With each day that passed
our isolation increased and the fatigue grew. There was
minimal time for sleep in the cramped tent. There was
also a gnawing hunger and doubts that perhaps what we
were attempting was impossible. No one had ever made
such a journey without support, and if things were hard
now, soon they would be harder, and all this added to the
stress.”
Participants of polar treks and traverses and, to a
smaller extent, polar camps, must contend with periods
of great physical exertion, fatigue, and exhaustion.19 Polar
environments are filled with hazards such as crevasses,
blizzards, slippery ice, frozen lakes, and open leads (ie, a
channel of water through a field or flow of ice), which
increase the likelihood of accidental injury and death.20,21
Cold temperatures are characteristic of polar
environments, especially for people on treks or those
who spend a substantial amount of time outdoors. Cycles
of daylight and darkness become longer with increasing
latitude, culminating in 6 months of light, or 6 months of
dark at the poles. The polar regions are also characterised
by low humidity and, depending on location, high altitude
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(eg, south pole). Physiological responses to these
environmental conditions include light-related changes
in circadian rhythms;22,23 altitude-related cardiopulmonary
symptoms;24 and cold-related changes in peripheral
circulation,25,26 hypothermia and frostbite,27–29 suppression
of the immune system,30,31 and hormonal changes.29,32,33
The psychosocial environment of polar expeditions is
characterised by isolation and confinement. Depending
on the location and time of year, expeditions are usually
physically isolated from the outside world, with darkness
and weather conditions exerting severe restrictions on
travel. People on such expeditions are separated from
their family and friends and consequently feel degrees of
emotional deprivation. Personal crises such as the death
of a family member, financial difficulties, or deterioration
of marital relations become magnified by the separation.
At the same time, people experience social confinement
within the expedition itself. Absence of privacy and
constant gossip are frequent on polar expeditions and
have a negative effect on social relations, especially
relations between men and women.34
Little separation between work and leisure can exist
because living and working spaces are close to one another,
and each person interacts with the same group of
individuals in both sets of activities. This constant
interaction can also create increased social conflict between
workers and supervisors, co-workers, cliques, or people
with conflicting personalities. Removing oneself from
tense social situations during the winter is not a viable
option. Travel for even brief periods to escape this
confinement is hampered by the extreme cold, darkness,
fatigue, and by policies promoting safety and reduction of
the risk of accidental injuries. Such a dilemma is illustrated
by an account of the Steger International polar expedition
in 1986: “Sitting there cold and hungry as the wind snapped
the tent walls like a whip, we grumbled among ourselves,
certain that the other group was hoarding more than its
share of the additional supply we had gotten from Drep
Camp. With a storm raging outside, another one was about
to erupt inside our tents. As our suspicions evolved into
anger, we shouted over to the other tent group, demanding
our full share of the soup.”35 However, the authors further
note: “As the accusations shot back and forth like darts, it
slowly became apparent to all of us that, in our state of
perpetual stress, hunger, and exhaustion, it was impossible
for us to look at the issue objectively. When the smoke
cleared, it proved to be an innocent matter with a simple
explanation.”35 The psychological effects experienced by
people on polar expeditions can be categorised as
symptoms, syndromes, disorders, and positive effects.
Symptoms
Several symptoms are repeatedly reported by people on
polar expeditions (panel 1), including headaches, boredom,
fatigue, inattention to personal hygiene, reduced motivation
with intellectual inertia, and increased appetite resulting
in weight gain. Gastrointestinal complaints, rheumatic
aches and pains, and increased sensitivity to physical and
social stimuli are also common symptoms.14,52 However,
the most common symptoms of people undertaking polar
expeditions include sleep disruption, impaired cognitive
performance, negative affect, and interpersonal tension
and conflict.
Sleep disruption
Difficulty falling or staying asleep, or both (popularly
known as big eye) are characteristic of people on polar
expeditions, especially at midwinter.15,37–40 A survey by
Palinkas34 recorded that 64·1% of people at McMurdo
Station in Antarctica reported some difficulty with sleep
in winter. Similarly, a summer expedition to the Antarctic
noted poor sleep in two of every three participants.41 In a
study of Russian miners in Svalbard, Norway, 81% of men
and 77% of women reported sleeping problems lasting for
at least 2 weeks.42 Other sleep-related studies recorded
sizable reductions in the amount of slow-wave and
rapid-eye-movement (REM) sleep in Antarctica44,45 and a
significant reduction in REM sleep in men working and
sleeping in the Arctic.46 These problems can mostly be
attributed to disruption of circadian rhythms in both
summer41,53 and winter,23 cold exposure,46 and psychosocial
stress.15,54 However, other studies noted no change in sleep
in people on expiditions in the Antarctic.55,56 Palinkas and
Panel 1: Psychological symptoms experienced by people
on polar expeditions
Somatic symptoms
Fatigue14,17,36
Weight gain17,34
Gastrointestinal complaints13,17
Rheumatic aches and pains13,17
Headaches10,13,14,24
Disturbed sleep (big eye)
Difficulty falling asleep15,17,24,37–43
Difficulty staying asleep15,17,24,37–43
Loss of slow-wave sleep44
Loss of rapid eye movement (REM) sleep44,45
Impaired cognition
Reduced accuracy and increased response time for cognitive
tasks of memory, vigilance, attention, and reasoning13–15,17,34,43,46,47
Easily hypnotised and susceptible to suggestion48,49
Intellectual inertia14,17,34
Spontaneous fugue states (Antarctic stare)17,34
Negative affect
Depressed mood12,13,15,17,34,43
Anger and irritability12,13,15,17,34,43
Anxiety12,13,17
Interpersonal tension and conflict
Toward group members12,17,18,34,35,50,51
Toward people not in the group8,17,34
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colleagues54 reported that total hours of sleep over 24 hr,
duration of longest (ie, night-time) sleep event, number of
sleep events, time of sleep onset, and quality of sleep
remained unchanged over the course of the austral winter
(March to October) in Antarctica. However, increasing
exposure to total darkness calculated on the basis of station
latitude was significantly associated with fewer total hours
of sleep, shorter duration of longest sleep event, later time
of sleep onset, and reduced quality of sleep.
Cognition impairment
Many people on polar expeditions in the Antarctic and
Arctic report impairment of memory, difficulty in
concentrating, and reduced alertness, seen as reductions
in accuracy and increases in response time in standardised
tests.14,46,47 During the 1989 winter season at McMurdo,
51·5% of residents reported difficulties with concentration
or memory.34 Other studies reported increased sus-
ceptibility to suggestion and hypnosis,48,49 and the incidence
of spontaneous fugue states.14 These symptoms have been
attributed to fatigue,14 absence of environmental
stimulation,57 and neurobehavioural effects of exposure to
cold.46 However, other studies recorded no reduction in
cognitive performance,58 reductions in some elements of
performance (eg, accuracy on a memory search task) but
not in others (eg, code substitution, reaction time, pattern
recognition),59 and a few studies have noted increases in
performance after a winter in the Antarctic.60,61
Negative affect
Depressed affect is one of the most common symptoms
people have on polar expeditions, closely followed by
anxiety and irritability. Accounts of polar treks frequently
cite instances of people who undergo periods of doubt
about their performance or sadness that they are unable
to meet personal or group expectations.18,35 Such feelings
are also pervasive in the polar research station, despite its
greater comfort than shelters used in traditional treks. In
the 1989 winter season at McMurdo, 62·1% of residents
reported feeling depressed and 47·6% reported feeling
more irritable than usual.34
Negative affect is generally transient and resolves without
clinical intervention. Yet clinically and statistically
significant increases in depressive symptoms are noted
during winter in Antarctica.62–64 These symptoms are
attributed to poor sleep,47 psychosocial stress15,34,57 and
neurobehavioural effects of long-term exposure to cold and
darkness.47,64,65 However, other polar expeditions note no
increase in depressed affect;66–68 increases in depression or
anxiety at the beginning of an expedition that subsequently
abate;69 more positive than negative affect;70,71 or decreases
in depression either in summer72 or winter.73–75
Interpersonal tension and conflict
Although people on polar expeditions often have great
social cohesion because of undergoing a common
experience,34 interpersonal conflict and tension is the
greatest source of stress in polar expeditions.17,18,50 An
illustration of such tension is provided in an account of a
polar trek: “Adding to the physical misery of scouting was
that it often proved to be a thankless job. Team members
who were thoroughly exasperated with the horrendous
workload of chopping ice and prying, pushing, and
pulling the thousand pound sled loads inch by inch for
endless hours each day, often thought the scout had the
easier job. Minor grumbling erupted from time to time
when day after day I was often out of sight of our caravan.
Some felt I was copping out of the brunt of the work.”35
Tension or conflict within an expedition can be
attributed to social comparisons that are inevitable in
every newly formed group,17,34 ostracism of crewmembers
who do not adhere to group norms,17,34,76 group
heterogeneity characterised by differences in gender77,78or
occupation,15,34,52 poor or ineffective leadership,76,79,80 and
competition between leaders18,68 or between leaders and
followers. Polar expeditions also frequently have some
degree of tension or conflict with external organisations.
Much of this external tension results from displacement
of intragroup tension and conflict.17,34 However, it might
also be a response to interference with established
routines, delays in arrival of relief parties or supplies, or
problems with communication.17,34 Other studies recorded
little or no tension between expedition members.67,70–72
Syndromes
Explorers in both the Antarctic and Arctic have long noted
the occurrence of seasonal variations in the aforementioned
symptoms.81 For instance, Americans resident in six
Antartic research stations for whole winters between 1963
and 1974 had significant increases in symptoms as the
season progressed.82 Members of the 11th Indian Antarctic
scientific expedition reported significant increases in
tobacco smoking in March and sleep disturbances in June,
reductions in rapport with fellow crewmembers in
September, and satisfaction with work and life situations
in December and January.39 An analogous pattern of
seasonal variation in mood and somatic complaints was
reported in Japanese residents at Asuka Station in
Antarctica.36 Another study of Japanese residents in the
Antarctic noted a decrease in hardiness at the end of the
winter.66 These seasonal changes can also be regarded as
three distinct syndromes or clusters of symptoms.
Winter-over syndrome
The cluster of symptoms consisting of sleep disturbance,
impaired cognition, negative affect, and interpersonal
tension and conflict experienced by people on polar
expeditions in the Antarctic was first referred to as the
winter-over syndrome by Strange and Youngman.43 Despite
its name, the winter-over syndrome is not a clinical entity,
and the severity and duration of symptoms are usually not
sufficient to warrant a DSM-IV diagnosis. Rather, it can be
more appropriately described as a subclinical condition
similar to subclinical depression.83 Several studies have
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noted that the symptoms of the winter-over syndrome
seem to increase after the midpoint of an expedition, with
some reduction in symptoms toward the end.50,82,84
This pattern is known as third-quarter phenomenon,85
and seems to be due to psychosocial factors, rather than
environmental ones, and is independent of expedition
duration. This syndrome results from the realisation that
the mission is only half completed, and that a period of
isolation and confinement equal to the first half remains.
However, this situation has not affected all expeditions,
especially polar treks in which the greatest stress occurs
around the point of no return (ie, the point at which
available supplies are insufficient to allow a return to the
point of origin), after which stress seems to diminish, as
seen during the Footsteps of Scott expedition in
Antarctica: “Our days on the glacier were some of the
most pleasant of the journey. The stress we felt on the
Barrier was perhaps due as much to the deprivation of
the landscape as it was to the uncertainty of what lay
ahead. Now we were past half-way and making excellent
progress.”18
Polar T3 syndrome
A second seasonal pattern of symptoms was seen in a
cohort of 22 men and women participating in a study of
cold-related changes in thyroid function and their effects
on mood. Profile of Mood States86 total mood disturbance
scores showed an effect over the 12 months of Antarctic
residence, with a sine distribution and two peak values
above the mesor, one in November and one in July, and a
trough below the mesor in March.65 This cyclic pattern is
almost identical to the seasonal variation in serum
thyrotropin-stimulating hormone concentrations seen at
the polar regions.47 Furthermore, the change in thyroid
function in people on polar expeditions is significantly
correlated with performance at cognitive tests and mood
symptoms.47,65
These changes are known as the polar T3 syndrome,
and share many characteristics with subclinical hypo-
thyroidism, including raised thyrotropin-stimulating
hormone concentrations and enhanced effects of
thyrotropin-releasing hormone.33,87,88 Furthermore, re-
ductions in cognitive performance and increases in
negative affect have been effectively treated with low
doses of thyroid supplements.47 The cognitive and
affective symptoms characteristic of polar T3 syndrome
are believed to represent a state of CNS hypothyroidism
accompanied by systemic euthyroidism.47,65
Subsyndromal seasonal affective disorder
A third pattern of seasonal changes in polar expeditions
seems to be related to variations in patterns of daylight
and darkness.89 A review of data collated from people
who spent an austral winter at Palmer, McMurdo, and
South Pole Stations in 1991 showed a significant increase
in prevalence of subsyndromal seasonal affective
disorder from late austral summer to mid-winter.64 The
association between depressive symptoms and time of
year is consistent with studies of individuals in the
general population that suggest an increased risk of
seasonal affective disorder and subsyndromal seasonal
affective disorder with decreased exposure to bright light
during the winter months.90,91 Light intensity has been
associated with suppression of melatonin;92–94
light-dependent modulation of circulating melatonin
concentrations conveys information about the
photoperiod.95 The melatonin rhythm is an important
transducer of photoperiod information for the timing of
many circadian and circannual physiological rhythms,96
including rhythms of energetic arousal, mood, and
cognitive performance.97,98
Psychiatric disorders
Although these syndromes can be commonplace in
people on polar expeditions, they rarely lead to a clinical
intervention. Generally, psychiatric disorders have
traditionally accounted for 1–5% of all station sick-calls or
outpatient visits at research stations in the Antarctic,5
although evidence suggests that this proportion is
decreasing.8 Psychiatric debriefings of 313 men and
women done at McMurdo and South Pole between 1994
and 1997 revealed that 5·2% of people fulfilled DSM-IV
criteria for at least one psychiatric disorder.99 The table
shows details of specific disorders.
Diagnosis DSM-IV
Code
Number
of cases
Rate per 100
debriefed
Weighted
Rate per 100
Mood disorders 13 4·2 1·7
Major depressive disorder, single episode 296.2 6 1·9 0·8
Major depressive disorder, recurrent 296.3 2 0·6 0·3
Dysthymic disorder 300.4 1 0·3 0·1
Depressive disorder not otherwise specified 311.0 4 1·3 0·5
Personality disorders 5 1·6 0·5
Schizoid personality disorder 301.2 2 0·6 0·3
Dependent personality disorder 301.6 2 0·6 0·3
Personality disorder not otherwise specified 301.9 1 0·3 0·1
Substance-related disorders 4 1·3 0·5
Alcohol dependence 303.9 2 0·6 0·3
Cannabis abuse 304.3 1 0·3 0·1
Alcohol abuse 305.0 1 0·3 0·1
Sleep disorders 9 2·9 1·1
Circadian rhythm sleep disorder 307.45 9 2·9 1·1
Adjustment disorders 12 3·8 1·6
Adjustment disorder with depressed mood 309.0 6 1·9 0·8
Adjustment disorder with anxiety 309.24 2 0·6 0·3
Adjustment disorder with mixed emotion or conduct 309.4 2 0·6 0·3
Adjustment disorder unspecified 309.9 2 0·6 0·3
Total DSM-IV Disorders 39 12·5 5·2
† Adjusted for differences between military or civilian status, age, and sex of participants in debriefing and all
expedition members.
Table: Unadjusted and weighted† prevalence (per 100 people debriefed) of DSM-IV disorders in people
on the United States Antarctic Program at end of an austral winter95
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Although these rates are lower than what might be
seen in the general population in the USA,100 they are
noteworthy because these men and women underwent
medical and psychiatric screening before the winter.
Norman101 reported a similar prevalence in crewmembers
of British Antarctic Survey stations who did not have
psychiatric screening. In the Arctic, Rosen, et al102
reported that 5·2% of men and 8·9% of women stationed
at an army installation in Alaska met the criteria for
seasonal affective disorder. However, the rates in this
largely non-indigenous population are comparable with
the 6·3% prevalence of seasonal affective disorder in a
group of Inuit living in the Canadian Arctic.103
Positive effects
Although people on polar expeditions might experience
symptoms, syndromes, and disorders in varying degrees,
they will probably also have positive effects. These effects
can be divided into two major categories, each of which
can be further subdivided. The two main categories are
(a) the inherently enjoyable characteristics of the situation,
and (b) the positive reactions to challenges of the
environment and having encountered and successfully
surmounted these challenges. Although very little
research has focused on either of these positive effects,
especially when compared with work that emphasises
negative effects and consequences, some research and a
substantial body of anecdotal evidence (autobiographies,
logbooks, letters, diaries, and interviews) document their
importance.
One point to remember is that positive and negative
reactions are not mutually exclusive. People can enjoy
and benefit from an experience even though they also
show signs of discomfort or psychological symptoms,
and vice versa. Studying positive aspects is not intended
to deny the existence of negative ones, but assessment of
either alone results in an incomplete and therefore
inaccurate picture of polar service.
Even amidst the acknowledged dangers and deprivations
of the early polar explorations, expeditioners frequently
referred to the beauty and grandeur of the land, ice, and
sea, the camaraderie and mutual support of the team, the
admirable qualities of their leader, and the thrill of facing
and overcoming the challenges of the environment.81
Those who study present-day polar sojourners report
very similar positive reactions.104 Many studies have
reported high emotional adjustment and positive feelings
in expedition members in both summer68,72 and winter.66,105
One study of French stations noted predominantly
favourable ratings of the recreational and leisure facilities
of stations, the quality of the food, and the individual’s
success in adjusting to the polar situation.50 An Australian
survey of 104 Antarctic residents reported that although a
greater range of negative reactions was listed, most of
them were infrequent; positive events were much more
frequent.105 A study of three Norwegian physicians who
crossed the inland glacier of Greenland on skis reported
a significant increase in subjective wellbeing in the
second half of the trip.106
One important piece of evidence of the overall benefit
of the polar experience is that so many people volunteer
for repeated assignments and are perturbed when asked
to consider never going back;105,107 as one researcher noted,
“Almost every member of the winter party considered his
Antarctic stay as one of the best experiences of his life.”108
Some frequently mentioned sources of polar enjoyment
are listed in panel 2. As in other extreme and unusual
environments, several kinds of positive reactions and
consequences are seen in people on polar expeditions.
Resilience and coping take place while in the environment;
salutogenesis and post-return growth refer to the
long-term effects of the experience.
Evidence of successful coping strategies for the physical
and psychosocial environmental conditions of polar
expeditions was obtained from investigations of mood
disturbances during early and late winter in 657 navy-
enlisted men who spent winter in Antarctica between 1963
and 1974. These studies recorded that symptoms of the
winter-over syndrome were inversely associated with the
altitude, latitude, and mean yearly temperature of the
research stations.82,110 An increase in symptom scores
from early to late winter was seen in 63·0% of these
individuals; no change in symptom scores was noted in
8·5%; and 28·4% had a decrease in symptom scores.
People who had a decrease in symptoms had less need
for social interaction (eg, low need to include others, low
need to be included by others, and low need to express
affection to others) than those whose symptoms
increased.82
Coping strategies, whether transferred from normal
life to the polar regions or developed in these regions, are
a source of pride and self-esteem because they help the
crew surmount challenges. Early sailors in the polar seas,
and both Arctic and Antarctic explorers of the heroic age,
Panel 2: Positive characteristics of the polar environment109
Natural grandeur, vastness, and beauty; feeling small and
insignificant and (paradoxically) strength
Excitement of encountering and learning about unknown
and unusual terrain, weather, and fauna
Efficiency; most needed facilities easily accessible
Coziness; cocooning inside the comfortable station
Balance of novelty and familiarity: sufficient novelty in
routines and in natural environment, with sufficiently
familiar capsule environment
Improvisation: trying new ways of working without
accustomed restrictions
Free time; for recreation, self-improvement, hobbies,
exercise, thinking
Time out from daily hassles and other negative aspects of
home-life
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used a range of tactics to increase enjoyment and
knowledge, including amateur theatricals, musicals,
ship’s or expedition’s newspapers, and lectures on topics
including the polar science of the day.111 Present-day
crews, at sea and on the ice, engage in similar activities,
and additionally have access to television, video,
telephones, and the internet. These activities seem to
effectively facilitate coping, stress reduction and pleasure
enhancement.108
Salutogenesis and post-return growth are related to
the ideas of eustress, based on Selye’s112 notion of stress
that has positive effects (as opposed to distress): they
are also related to the positive psychology movement.113
The important distinction between salutogenesis and
post-return growth on the one hand and resilience and
coping on the other is that resilience and coping refer
to ways of avoiding or warding off negative effects,
whereas the salutogenesis and post-return growth refer
to improvements in psychological characteristics or
processes.
Salutogenesis is a term coined by the late Israeli
sociologist, Aaron Antonovsky,114 who contrasted it with
the word pathogenesis. Salutogenic experiences therefore
are those that lead to heightened strength, depth of insight,
improved relations with others, increased self-confidence
and humane values, and many other favourable changes.
Such experiences are, as the term implies, health-
generating; pathogenic experiences have the opposite
effect, they are illness-generating. Comparable events or
experiences can be pathogenic or salutogenic for different
people, or for one person at different times.
Post-return growth is a paraphrase of the label, post-
traumatic growth, originated by Tedeschi and Calhoun.115
The basic idea is that traumatic experiences can lead to
positive changes in characteristics such as coping skills
and resilience, self-esteem, self-confidence, changes in
perspective and values, and increased self-awareness. If
positive changes happen to people who survive extreme
trauma, such as military service, persecution, violent
crime, or child abuse, they might also happen to those who
return from challenging but not traumatic situations, such
as time spent in an extreme or unusual environment.109,116
The best evidence of salutogenesis or post-return growth
thus far is the finding that American naval crew who spent
winter in the Antarctic had better health records after their
return and more successful careers than a control group
who had volunteered for Antarctic assignments and passed
the screening tests, but had never been deployed.117 As a
group, those stationed in Antarctica had 20% fewer first
hospital admissions in the remainder of their time in the
military (5–13 years). A salutogenic outcome could also
result from achievement of the polar expedition’s goals. An
example of such an outcome is detailed in a study, by Atlis,
et al,118 of two women who successfully traversed the length
of the Antarctic continent. Their main motivations for the
expedition were not only the challenge of the environment,
but also to be role models to girls and women, and to
provide an educational curriculum to schools after the
expedition. Panel 3 shows other psychosocial states that
might result from salutogenic experiences and post-return
growth.
Prevention and promotion
Expedition leaders have tried several different techniques,
including many leisure activities, for prevention of
psychological distress and poor performance, and
promotion of team member wellbeing. Occasionally,
measures intended to reduce stress and improve
wellbeing, such as availability of alcohol during the polar
winter, in fact reduced individual performance and
increased social tension and conflict.57 Engaging in
training, both individually35 and as a crew34 also facilitates
psychological adaptation to the expedition through
enhanced self-confidence. Availability of information and
support to family members, as is provided to members of
the Australian National Antarctic Research Expedition119
also can enable coping in people on polar expeditions by
improvement of access to social support and reductions in
the stress associated with separation from family.
Perhaps the most effective method for prevention of
psychogenic effects during polar expeditions is a
programme of psychological screening and selection of
participants. Such programmes are rarely, if ever,
adopted for treks and camps. Several nations operating
research stations in the Antarctic have such programmes
for individuals who expect to stay for 12 months or
longer, including the austral winter when medical
evacuation is exceedingly difficult if not impossible.
These programmes typically consist of structured
interviews by psychiatrists or clinical psychologists,
standardised psychometric instruments such as the
Minnesota Multiphasic Personality Inventory120 and the
Michigan Alcoholism Screening Test,121 and reviews of
medical and employment records. People on expeditions
generally have low prevalence of psychiatric disorders
Panel 3: Salutogenic after effects of polar expeditions109
Affiliation, intimacy with fellow crewmembers
Sense of personal acheivement
Cooperativeness in work and play
Striving toward important goals
Courage, resoluteness, indomitability
Excitement, curiosity
Increased self-esteem and self-efficacy from challenges
sought deliberately
Hardiness, resiliency, coping
Improved health
Group solidarity, cohesiveness, shared values
Increased individuality, reduced conformity
Reflection, contemplation
Ability to set and achieve higher goals, and changes in thinking
Increased sense of humanity
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and low proportion of total outpatient visits, thus these
programmes are generally considered to be successful
at detecting individuals who would have trouble coping
with polar life.
Screening and selection procedures including pre-
expedition psychiatric evaluations to select out people who
could have psychiatric disorders are but one element of the
psychological support provided for people on polar
expeditions. Other elements include; psychiatrists and
clinical psychologists consulting with expedition physicians
and crewmembers via telecommunications networks, both
in response to disasters and emergencies affecting the
entire expedition and in response to individual symptoms;
training of crewmembers in personal coping strategies,
teamwork, leadership; and giving psychological support to
trauma victims;122 medical evacuation by air if necessary and
possible (usually restricted to the summer months); and
debriefings by clinicians after the expedition to intervene in
crises and give reassurance before the return home.
Additionally, a long tradition of research has identified
individual characteristics that predict for optimum per-
formance and adaptation in polar expeditions
(panel 4).16,52,126,130 Several of the individual traits are
associated with high emotional stability, task ability, and
social compatibility in long-term (ie, station)51,82,127,129,131 and
short-term (ie, treks and field camp)123–125 expeditions.
Characteristics of effective groups include appropriate and
effective leadership, similarities in approach to
problem-solving, respect for each other’s opinions, and
shared decisionmaking.51,129,132,133
Nevertheless, in addition to individuals being selected-
out of some types of expedition, personality traits generally
have little ability to predict behaviour and performance on
polar expeditions because people who want do go on
expedition are generally highly motivated volunteers who
show smaller variation in personality traits than typically
seen in the general population.3,16,128 Baseline measures of
personality, stress, and coping are weak prospective
predictors of behaviour and performance during the winter
because such performance is affected more by the
situational characteristics of isolation, confinement, and
extreme environments than by stable traits of
individuals.134,135 These characteristics include the stressors
(eg, isolation, confinement), and the scarcity of resources
necessary to cope with these stressors.
Conclusion
Over the past century, we have learned much about the
psychological changes experienced by polar
expeditioners. These changes range from the harmful
or pathogenic to the beneficial or salutogenic. For most
expeditioners, the rewards have far outweighed the
risks. Nevertheless, continued research on the
psychological effects of polar expeditions is important
because it helps us to better understand some of the
underlying principles of behaviour in any environment
and in particular, behaviour in isolated and confined
environments. This understanding is seen as especially
important in situations like long-duration missions in
space where the opportunities for doing similar
investigations is limited by logistical constraints and
small numbers of participants. This research will also
be increasingly important as more and more people, old
and young, seek out the challenge and beauty of the
circumpolar regions.
Improvement of select-out procedures can
reduce the frequency and operational effects of psychiatric
disorders and other pathogenic changes, although
improvement of select-in procedures can improve quality
of life, enhance task performance, and increase the
likelihood of beneficial or salutogenic changes. Such
improvements would include the development of
guidelines for the screening and selection of individuals
for various types of polar expeditions. Assessment and
classification of adaptive and maladaptive forms of
behaviour that are specific to polar expeditions,
developing protocols and resources necessary to provide
psychological support, and training polar expeditioners
to cope with the stress of isolation, confinement, and
harsh physical environments is also recommended.
Such procedures should be designed to predict for as
well as promote the three essential components of
successful polar expeditions: task ability, emotional
stability, and social compatibility.
Conflict of interest statement
We declare that we have no conflict of interest.
Acknowledgments
This work was supported by the US National Science Foundation
(OPP-00-90343).
Panel 4: Characteristics of the ideal person for polar
expeditions
Short expeditions
High motivation to achieve16,52,70,123
High sense of adventure123,124
Low susceptibility to anxiety71,125
Long expeditions
Aged older than 30 years51,52,124
Emotionally stable52
Few symptoms of depression62,126,127
Low neuroticism127,128
Introverted but socially adept15,127
Satisfied with social support16,62
Not greatly extraverted or assertive43,127
No great need for social interaction82,127
Low demands for social support10,82,127
Sensitive to needs of others10,34,82,127
Desire for optimistic friends127
High tolerance of little mental stimulation129
Does not become bored easily10,82,127
High tolerance to lack of achievement82,127
Low need of order127
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