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 Table of Contents  
Year : 2015  |  Volume : 20  |  Issue : 2  |  Page : 65-70

Psychological health in the summer team of an Indian expedition to Antarctica

1 Department of Psychiatry, All India Institute of Medical Sciences, New Delhi, India
2 National Centre for Antarctic and Ocean Health, Goa, India

Date of Web Publication20-Jan-2016

Correspondence Address:
Abhijeet Bhatia
Department of ENT, NEIGRIHMS, Mawdiangdiang, Shillong - 793 018, Meghalaya
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0971-8990.174596

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Context: Number of scientific personnel traveling to Antarctica for short summer stay far outnumbers winter personnel. Hence, psychological issues confronting such personnel need to be analyzed in detail. This study aims to study changes in psychological health, cognitive functioning, changes in motivation levels, and tobacco and alcohol consumption during a summer in Antarctica. Aims: To study changes in psychological health, cognitive functioning, changes in motivation levels and tobacco and alcohol consumption during a summer in Antarctica. Setting and Design: This cohort study was conducted on 33 summer team members of 27 th Indian Scientific Expedition to Antarctica. Subjects and Methods: Seven instruments were administered to assess general health, alcohol and tobacco dependence, memory and cognitive functioning of the team members. Statistical Analysis Used: The data were analyzed for statistical significance using nonparametric Wilcoxon Signed Rank Sum Test. Results: Scores on social dysfunction, depression, and somatic symptoms increased. Tobacco consumption also increased concomitantly. However, memory and cognitive function were not impaired. Alcohol consumption did not change. None of the subjects needed medication or evacuation for psychological difficulties. Conclusion: Psychological issues might manifest themselves even during a short stay in Antarctica during the summer season.

Keywords: Antarctica, psychological impact, summer

How to cite this article:
Khandelwal S, Bhatia A, Mishra AK. Psychological health in the summer team of an Indian expedition to Antarctica. J Mental Health Hum Behav 2015;20:65-70

How to cite this URL:
Khandelwal S, Bhatia A, Mishra AK. Psychological health in the summer team of an Indian expedition to Antarctica. J Mental Health Hum Behav [serial online] 2015 [cited 2023 Mar 26];20:65-70. Available from: https://www.jmhhb.org/text.asp?2015/20/2/65/174596

  Introduction Top

Antarctica is the only continent with no native population. The human communities spread out around Antarctica are temporary and consist primarily of scientists and support staff. The winter teams once inducted have to spend about 1 year on the continent. They are housed in permanent and temporary national Antarctic bases, the purpose of which is to conduct scientific research for peaceful purposes as directed by the Antarctic treaty (India is signatory to this treaty) that governs human activities in Antarctica. [1] Since the conditions in Antarctica in terms of remoteness and extreme climate and terrain are unique to the continent, increasing human activities have necessitated a greater understanding of the impact of short-term and long-term stay in Antarctica on human health, mental and physical. Its environment is described as extreme because survival is impossible for the unprotected and ill-provisioned individual. [2] Its natural environment of extremely low temperatures is dangerous and not easily accessible makes it stressful. However, physical conditions may not be the strongest stressors in Antarctica. The psychological impact of prolonged residence in Antarctica is substantial. Three main factors have been implicated as most difficult to cope with prolonged isolation or separation from family and friends; confinement in small groups; and occupational, station maintenance, and leisurely activities which involve prolonged periods of underemployment with intervening periods of high workload. [2] Most common symptoms reported in the winter team are insomnia, irritability, headache, anxiety, depression, lack of motivation, and concentration. [3],[4],[5],[6],[7]

Though minor mental health problems are very common, they are temporary and cause only 4-5% of the total health-related morbidity. A number of studies have reported impact on psychological health among long-term residents doing winter-over (scientists and support staff staying over 1 year). Psychological reactions have been observed to occur in three stages in Antarctica: (a) Increased anxiety, (b) depression and settling down to routine and (c) emotional outbursts, aggressiveness, open conflicts, and decreased motivation and morale. This last and most critical stage occurs around the third quarter of the isolation period and has been termed the third quarter phenomenon. [8],[9],[10] However, studies on short-term visitors, who spend only summer time and far exceed the winterers numerically, are not well-documented.

Studies on psychological impact on Indian expeditioners are few but significant. One such study reported that June (mid-winter) was associated with insomnia and September (third quarter) was associated with poor interpersonal relationships. Interestingly, smoking was found to increase in March signifying the increase in stress at the beginning of the isolation period. Work dissatisfaction was reported with continued isolation (December/January). [6]

In view of the above information and research findings the current study attempted to carry out a structured and longitudinal assessment of members of Indian expedition to Antarctica in the summer team of 27 th Indian Scientific Expedition to Antarctica (ISEA). It attempted to study changes in psychological health, cognitive functioning, changes in motivation levels, and tobacco and alcohol consumption during a summer in Antarctica.

India has established a permanent scientific station, Maitri, at Antarctica in the year 1988, which is a well-equipped all-weather station to support scientific and logistic activities and research. Each year expedition starts in the month of November/December and continues for next 12-14 months. However, the summer team returns to India by March/April.

  Subjects and Methods Top

Study design and setting

This longitudinal observational cohort study was carried out on 33 members of the summer team of the 27 th ISEA. All the team members were selected from among a pool of volunteers by an interview followed by detailed Medical Examination. The team members comprised of scientific and logistics staff. Following team selection, the team members were sent to a high altitude location in the Indian Himalayas for acclimatization, orientation, and training in survival techniques in a hostile environment. The study was carried out on board the expedition vessel, MV Emerald Sea during its journey from Goa to Antarctic continent, and at the Indian Antarctic station, Maitri, from November 2007 to March 2008. The study period covered the duration from the induction of the first batch of summer team members from India in 1 st week of November 2007 by air, until the return of the expedition vessel to India in March 2008.

Study group

Thirty-three members of summer team of 27 th ISEA were included in the study. The investigators were excluded.

Instruments used

A battery of seven instruments was administered to the participants during the study:

  • PGI memory scale: [11],[12] This was developed as a short, simple, objective, and valid test of memory and cognitive function. It is administered in Hindi and has been designed for use by the Indian population. The instrument consists of 10 subsets, out of which eight have been used in the current study. These include remote memory, recent memory, mental balance, attention and concentration, delayed recall, immediate recall, verbal retention for a similar pair and verbal retention for the dissimilar pair. Visual retention and recognition were not included in our study because of logistical issues in a remote location

    The PGI memory scale has test-retest reliability over a period of 1 week from 0.69 to 0.85 and for the total test about 0.90 (test-retest and split-half). [13]
  • General Health Questionnaire (GHQ) (28 item Hindi version): [14] The 28 item version of the GHQ was designed primarily for research purposes and is also useful as a measure of psychological well-being. It consists of four subscales: Somatic symptoms (GHQ1), anxiety and insomnia (GHQ2), social dysfunction (GHQ3), and depression (GHQ4). Compared to the other versions of GHQ, the 28 item version has the advantage that analysis can be performed within each of the four subscales
  • Hindi Mental Scale Examination (HMSE): [15] This is the Hindi version of the Mini-Mental Scale Examination modified to enable the universal administration to literate as well as illiterate individuals. This scale measures cognitive functioning and can be used to screen for dementia. The scale has eleven subscales: Orientation to time, orientation to place, registration, attention, recall, naming, repetition, visual command, three step tasks, sentence, and copying a figure. All the subscales have been included in the current study
  • Well-being scale (WBS): A five- point Likert type WBS was used for self-assessment of motivation, confidence, efficiency, energy level, and mood. The parameters were measured on a scale of 1-10
  • Fagerstrom test for nicotine dependence (FTND): [16] This is a standard instrument used to assess the degree of tobacco addiction. The instrument consists of six questions, each of which has graded responses. A higher score indicates greater nicotine dependence. The Cronbach's alpha coefficient for FTND is reported as 0.86 [17]
  • Alcohol use disorder identification test (AUDIT): [18] This is an instrument designed by the world health organization to identify individuals with harmful and hazardous alcohol consumption pattern. The AUDIT consists of ten standardized questions with graded responses. Higher scores indicate higher alcohol dependence. The reliability of AUDIT questionnaire has been reported to be 0.70 or higher in diverse population settings [19]
  • CAGE questionnaire: [20] This is a brief, four-item instrument used for screening for alcoholism. A greater number of responses in the affirmative indicate greater alcohol dependence. The sensitivity and specificity for CAGE questionnaire has been documented as 93.8% and 85.5%, respectively. [21]

Data collection procedure

Informed consent was taken from all the participants, and they were assured of complete confidentiality. The questionnaires were first administered immediately after reaching Antarctica (November 2007) in the case of individuals being inducted by air (n = 5). Participants being inducted by sea were first administered the questionnaires on board the expedition vessel (n = 28) in December 2007. The questionnaires were next administered in February-March 2008 on board the expedition vessel after departure from Maitri. The minimum gap between two assessments for each member was 3 months. The data for the summer team were thus collected twice, at the beginning and toward the end of the expedition.

Statistical analysis

The data thus collected were recorded on excel worksheets. The data for the two spells were compared and analyzed for statistical significance using nonparametric Wilcoxon Signed Rank Sum Test. The change in each parameter was considered significant if P < 0.05. Each of the subscales for the GHQ was analyzed separately. For the rest of the instruments, the total score was considered for analysis.

  Results Top

A total of 33 summer team members, all males, were included in the study. Two members could not participate in the second assessment. The mean age of the group was 37.16 ± 10.16 years.

The results of the Wilcoxon Signed Rank Sum test [Table 1] revealed that among subscales of the GHQ, social dysfunction increased with the difference in the two readings being significant (P < 0.01). The degree of depression was observed to decrease with the progress of the expedition. Somatic symptoms also increased, but the increase was not so significant (P = 0.08). Anxiety and insomnia did not register a significant change.
Table 1: Results of non parametric Wilcoxon Signed Rank Sum Test (original)

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The tobacco addiction also increased significantly (P = 0.06), whereas the degree of alcohol use, as measured by AUDIT and CAGE questionnaires, did not register any significant change. The memory, cognitive function, and well-being as assessed by PGI, HMSE and WBS too did not change significantly.

  Discussion Top

The results of the current study reveal that over a short-term stay of the team in Antarctica, scores on social dysfunction, depression, and somatic symptoms increased as assessed by the GHQ-28. Tobacco consumption also increased concomitantly. However, memory and cognitive function were not impaired. Alcohol consumption did not change. None of the subjects needed medication or evacuation for psychological difficulties. Furthermore, none of the nonsmokers or nondrinkers was initiated into the habit during the expedition. On clinical assessment, none of the expedition members fulfilled criteria for any mental disorder.

The investigators have attempted to study the changes, if any, in psychological adaptation and cognitive functioning during the brief summer season in Antarctica. The summer season is a relatively less stressful period. The usual stress factors associated with winter residence in Antarctica are absent. The isolation is not complete, with limited flights and the expedition vessel replenishing the supplies, prolonged periods of daylight, a continuous stream of visitors to the continent, expeditioners from various nations and also tourists, relative ease of evacuation, fresh food, and prolonged periods of outdoor activity to name a few. However, the stress factors are still present in a subdued form relative to the winter expedition. The summer expedition might last for 4 months in the Indian context, from departure from India to return. The continent is barren, temperatures persist around or below freezing point, there is continuous sunshine for 2 months, spells of poor weather are frequent, communication facilities are relatively poor, and flights are infrequent. Even during the peak of the hectic summer season, Antarctica continues to be a desolate, inhospitable continent. Hence, it would not be surprising to find stress reactions in the team members, though severe psychiatric disturbances may be unusual.

For doing this study, the expedition members were assessed twice, first at the beginning of the expedition, and the second time on their return journey after they had spent at least 3 months in Antarctica.

Social dysfunction refers to the subject's assessment of his satisfaction with his performance in various social roles and activities during the expedition. [14] The subjects of the current study were not as satisfied with their fulfillment of social roles and responsibilities toward the end of the summer expedition as they were at the beginning. However, it did not affect their assignment or daily chores, and there was no apparent issue of indiscipline or open confrontation with any other member of the expedition. Similar trend in individual morale and teamwork life was observed during an Antarctic traverse by Wood et al. They also attributed this observation partially to a rise in interpersonal tensions, which are among the most common psychological afflictions in Antarctica and in other small, confined, and isolated communities, especially those residing in extreme conditions, including space travelers and submariners. Environmental factors and personality traits of individual team members play an important part in difficulties in interpersonal relationships. [22] The various social issues an individual may experience in Antarctica include withdrawal within oneself, fear of being misunderstood or underestimated, dependency on others, seeking the support of others, criticism, irritability, distrust, rigidity, strong rivalry with others, verbal or physical aggressiveness, self-centeredness, over-dramatization of incidents, cause of tension inside the group, and carelessness about basic social rules. [2] These traits were not assessed in the current study.

Somatic symptoms also increased in severity towards the end of the expedition in the current study. The somatic symptoms considered include headaches and heaviness in the head, the need for medication to feel healthy and fatigue. Fatigue, weight gain, gastrointestinal complaints, rheumatic aches and pains, headaches are the common reactions that might occur during polar expeditions. [23] Increased scores in depression too was observed during the current study. Severe depression indicates an inability to cope with stressors in the Antarctic environment and is usually associated with a prolonged stay on the continent. [2] In our sample, depressive scores seem to have increased at the end of 3 months of stay in Antarctica, but none of the members met criteria for a syndromal diagnosis on a personal clinical interview of each member by the first author. Depressive affect is among the most common afflictions on polar expeditions. Around 62% team members reported depressive affect in the US expedition in 1989. It is usually mild, transient and resolves without intervention. Such changes usually occur during the winter due to insomnia, psychosocial stress, and psychological effect of long-term exposure to cold and darkness. Other expeditions have reported an increase in depression during the summer, and still others have reported a decrease in depression during summer. [23] At the same time, many other studies have failed to demonstrate any clear-cut association between latitude and incidence of seasonal affective disorder (SAD). Though SAD usually occurs during the winter months, it is also known to occur during the summer season. [24]

Out of the four subscales of GHQ-28, only anxiety and insomnia were not observed to change significantly. It has also been reported that there was no change in anxiety levels during Antarctic expeditions. [25] Anxiety has typically been associated with the initial part of Antarctic residence or isolation. The first few months of stay in Antarctica represents the stage of adaptation to the polar environment when the team members are adapting to the Antarctic environment. This has often been described as more stressful than the winter part of the expedition. Anxiety might also increase prior to departure from Antarctica, in anticipation of a return to "normal" life. [2],[6],[26]

In an Indian study, no significant insomnia was reported during the summer months in Antarctica. [6] Insomnia is more common after the adaptive phase. It has been regarded as a somatic symptom. [2] It has been attributed to disruption of circadian rhythm, cold exposure, and psychosocial stress. All the sleep parameters, i.e., the total duration of sleep, a longest sleep event, time of sleep onset, and quality of sleep can be impaired. [23]

Memory and cognitive functioning were not affected in the current study. Similar results were obtained during a 100-day Antarctica traverses by Australian teams. However, these teams consisted of only six members each. Cognitive functioning and decrements in memory are related to depression. This can lead to judgmental errors and poor decision making in space personnel too. [22] Cognitive impairment may include impairment of memory, difficulty in concentration, reduced alertness, increased susceptibility to suggestions, and hypnosis and also increased susceptibility to the fugue. Fatigue, lack of environmental stimulation and psychological effects of cold may be implicated. [23] Cognition might be affected by physiological changes such as alterations in thyroid function. However, this is only during prolonged residence in Antarctica. [26]

Increased alcohol consumption was not observed in the summer team of the 27 th ISEA. Another Indian study too did not report any increased alcohol intake. However, this study was on the winter team. The alcohol consumption was observed to increase in American bases in the winter teams. The severity of the climate and extent and duration of isolation have a major bearing on the degree of alcohol abuse in Antarctic stations. [6] Alcohol is available in Indian as well as other Antarctic bases as a means to reduce stress and promote social interaction. However, it has been observed in Antarctica that alcohol is one of the factors that reduce individual performance and affects team cohesion. Individuals with a drinking problem are not allowed on Antarctic expeditions for this reason. [23],[27]

Smoking was observed to increase in this study. Bhargav et al. reported an increased incidence of smoking in the early part of an Indian winter expedition. They attributed it to an initial reaction to a challenging situation and considered it as a response to increased anxiety. [6] Smoking is restricted in Indian and other stations due to the fire hazard in a dry atmosphere. [27]

Antarctic living might also have salutogenic effects probably because of a greater effort to adapt to an unfamiliar and hostile environment during the early part of winter. [26] Thus, the current study reveals that psychological issues might manifest themselves even during a short stay in Antarctica during the summer season, though of the lesser magnitude than in the winter teams. Since most studies concentrate only on the psychological health of the winter teams, it is imperative that more broad-based studies be carried out on the summer teams as well to gain a better perspective into the psychological aspects of Antarctic expeditions, and extrapolate them to analogous situations such as space travel.

The midnight sun is one of the major factors influencing psychological behavior in Antarctica due to disruption of diurnal rhythm among residents. It has been found to lead to insomnia and mood and performance disturbances. Following a strict work schedule and daily routine is essential to minimize the effects of the midnight sun by maintaining the normal diurnal variation of serum cortisol levels. [28],[29] Extended periods of light during summer might also lead to increased impulsiveness and aggressiveness or depression. [30] Patients with a migraine are more likely to have a headache during the period of midnight sun than the polar night. [31]

A major limitation of the study sample was only 33 subjects. This limitation is unavoidable because of the small size of Antarctic expeditions. Currently, the trend is towards smaller and smaller expeditions being sent to the Antarctica in order to optimally utilize available resources. Hence, the only way to obtain more representative sample sizes is to conduct similar studies on multiple expeditions at the same station over a few years or to conduct similar studies at multiple Antarctic stations and vessels simultaneously.


The 27 th ISEA was organized and coordinated by National Centre for Antarctic and Ocean Research, Ministry of Earth Sciences, Government of India. The authors are grateful to all the team members of 27 th ISEA for their cooperation during the conduct of this study. This is NCAOR publication number 34/2015.

Financial support and sponsorship

National Centre for Antarctic and Ocean Research, Goa, India.

Conflicts of interest

There are no conflicts of interest.

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