PREDICTORS OF IDEAS ABOUT SEASONAL PSYCHOLOGICAL

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Predictors of Ideas about Seasonal Psychological Fluctuations Tim Brennen, Catherine Hall, Bas Verplanken and Julia Nunn Environment and Behavior 2005; 37; 220 DOI: 10.1177/0013916504269648 The online version of this article can be found at: http://eab.sagepub.com/cgi/content/abstract/37/2/220

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ENVIRONMENT 10.1177/0013916504269648 Brennen et al. / SEASONAL AND BEHA PSYCHOLOGICAL VIOR / March 2005 FLUCTUATIONS

PREDICTORS OF IDEAS ABOUT SEASONAL PSYCHOLOGICAL FLUCTUATIONS TIM BRENNEN is professor of cognitive psychology at the University of Oslo, Norway. His studies of cognition over the annual cycle are an example of his interest in applied and theoretical aspects of cognitive psychology. CATHERINE HALL participated in this study as part of her psychology degree at Goldsmiths College, University of London. She is now studying for her degree in medicine at the University of Newcastle. BAS VERPLANKEN is professor of social psychology at the University of Tromsø, Norway. His main research interests are attitude-behavior relationships, consumer behavior, health behavior, and decision making. JULIA NUNN is senior lecturer in the Department of Psychology, Goldsmiths College, University of London. Her main research interest is the cognitive neuroscience of memory.

ABSTRACT: This article reports a study of attitudes and beliefs about seasonal psychological cycles in a sample of 160 people living in London. Participants rated their perceptions of seasonal fluctuations on cognitive, emotional, physical, and social functioning in themselves, in others at the same latitude, and in the Arctic population by means of the Seasonal Pattern Assessment Questionnaire and a specially designed questionnaire. They also completed a test of astronomical knowledge, a test of knowledge about seasonal affective disorder, and an instrument measuring the Big Five personality dimensions. Seasonal mood swings correlated positively with SAD knowledge and extraversion and negatively with the respondents’ emotional stability and knowledge of astronomy. Perception of seasonal change in others appeared to be mediated by their perceptions of their own seasonal fluctuations. Generally, participants did not have unwarranted negative predictions about the impact of the annual cycle on psychological swings in the Arctic. Keywords:

seasons; psychological functioning; seasonal affective disorder; Arctic; personality

ENVIRONMENT AND BEHAVIOR, Vol. 37 No. 2, March 2005 220-236 DOI: 10.1177/0013916504269648 © 2005 Sage Publications

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Brennen et al. / SEASONAL PSYCHOLOGICAL FLUCTUATIONS 221

First, some facts: The Earth makes a full revolution on its axis once a day, and the angle at which it rotates is tilted by 23.5 degrees relative to the perpendicular of its orbit around the sun. The Earth orbits the sun every 365.2422 days (Kaler, 1994). These facts in combination give rise to the different seasons on Earth by causing differences in day length over the annual cycle. Between the spring and the autumn equinox, places in the northern hemisphere have more day than night, whereas between the autumn and the spring equinox they have more night than day, and the converse is true for places in the southern hemisphere. Furthermore, the farther a place is from the equator the more extremely the light conditions vary over the annual cycle, culminating in the fact that at the North and South Poles, each annual cycle consists of 6 months of daylight followed by 6 months with the sun below the horizon. From March to September, there is daylight at the North Pole; from September to March, there is daylight at the South Pole. These astronomical facts are relevant to the present study in two ways, as will become evident below. First, the changes in day length are presumed to have effects on psychological functioning. Modern psychiatry describes a condition known as seasonal affective disorder (SAD). Individuals with SAD have recurrent episodes of depression occurring during winter, with complete remission of the symptoms in summer. The initial report from Rosenthal et al. (1984) aroused great interest, and there has since been published upwards of 1,000 articles on the topic. Much less research has investigated cognitive swings over the annual cycle (see Brennen, 2001; Brennen, Martinussen, Hansen, & Hjemdal, 1999; Taylor & Duncum, 1987). In the present study, a sample of participants living in London, at 51 degrees north, was asked about the seasonal fluctuations in psychological functioning that they themselves experience as well as about their intuitions about what other people living at the same latitude experience and about what people living north of the Arctic Circle (66.5 degrees north) experience. The study also investigated what other beliefs and knowledge states are associated with beliefs about seasonal psychological fluctuations. Specifically, a questionnaire was devised to test participants on their grasp of facts about the solar system.

PSYCHOLOGY AND THE SEASONS SAD

According to DSM-IV criteria, to qualify for a diagnosis of SAD, sufferers must demonstrate a clear association between the onset of major


222 ENVIRONMENT AND BEHAVIOR / March 2005

depression at a regular and particular time of year, show remission of symptoms at a characteristic time of year, have had at least two episodes that have occurred at the same time of year, and the seasonal depressive episodes must outnumber the nonseasonal episodes of depression that may have occurred in an individual’s lifetime. Although the majority report such episodes of depression occurring during the winter months, SAD is also reported to occur in the summer, but it is much less common. Since the discovery of SAD, a milder form has been identified. Labelled subsyndromal SAD (S-SAD) by Kasper, Rogers, et al. (1989) and winter blues by Rosenthal (1998), this milder form is diagnosed when individuals report seasonal changes in mood that cause mild dysfunction and vegetative symptoms similar to SAD but below the level of clinical significance. More generally, the tendency to experience seasonal swings in mood and behavior is called seasonality. Even people who do not qualify for the criteria for S-SAD report changes in mood in winter. For instance, Kasper, Wehr, Bartko, Gaist, and Rosenthal (1989) reported that in the United States, 92% of their sample reported seasonal fluctuations in mood and behavior. Therefore, seasonal mood fluctuations can be thought of as a dimension, with those suffering from SAD at one end and those experiencing no seasonal changes at the other end, with S-SAD between the two extremes (Kasper, Rogers, et al., 1989). PREVALENCE OF SAD

Estimates of SAD prevalence vary from 0% to 15% among studies, and this may be due to methodological differences between studies. The disorder appears less prevalent among 20-year-olds and 50-year-olds than among those at ages in between (Booker & Hellekson, 1992; Eagles et al., 1999). Women have a higher incidence of SAD (Hodges & Marks, 1998; Kane & Lowis, 1999; Lee & Chan, 1998; Magnusson & Stefansson, 1993; cf. Han et al., 2000). LATITUDE AND MOOD

The fact that human mood can fluctuate in response to the seasons has indicated that this specific affective disorder may have a biological etiology and could be a physiological response to the reduction in the amount of daylight, possibly by disturbing circadian rhythms in melatonin release (Schlager, 2001; Thompson & Isaacs, 1988). If light is the underlying cause of SAD, one would expect that higher latitudes, which get less daylight in winter, would be associated with higher prevalence of SAD. A large study by



Rosen et al. (1990) examined the relationship between prevalence of SAD and latitude in the United States. At four latitudes ranging from 27 degrees north to 42.5 degrees north, prevalence ranged from 1.4% to 9.7%, and the correlation between prevalence and latitude was .11. As the authors acknowledge, the sampling procedure may overestimate SAD incidence and, in any case, the association is weak. Recent reviews of the studies of the association between SAD prevalence and latitude show an overall correlation of .001 (Mersch, 2001; Mersch, Middendorp, Bouhuys, Beersma, & van den Hoofdakker, 1999b). Furthermore, Europe, most of which is north of the United States, has a significantly lower mean prevalence. However, within Europe and the United States separately, there were positive correlations of 0.54 and 0.9, respectively. This shows there must be many factors more important than latitude in determining SAD prevalence. Hansen, Jacobsen, and Husby (1991) showed that living at a very northerly latitude does not necessarily lead to a high prevalence of mood problems. They tested about 50% of the population living in Tromsø (69 degrees north), a sample of over 7,000 people, and found few problems with sleeping, mood, and coping in the middle of winter. Only 7% of participants reported more than one of these being a problem. Over the past 4 decades, the psychosocial well-being of scientists and support staff living for the winter months on research stations on Antarctica has been closely monitored (Suedfeld & Weiss, 2000). A simple interpretation of the latitude hypothesis would be that SAD symptoms should be widespread among these groups. This was only partially confirmed by Palinkas, Houseal, and Rosenthal (1996) who examined the relationship between mood fluctuations and latitude prospectively in a clinically normal group of 70 men and women with no history of SAD who spent the winter on Antarctica. The prevalence of S-SAD increased from 10% to 30% over the winter; however, only one case of SAD was reported. Furthermore, Palinkas and Houseal (2000) described the seasonal changes in mood of workers at Antarctic research stations in stages of challenge, accomplishment, and exhaustion, which has a qualitatively different feel to the symptomatology of SAD. There is evidence, however, that winters at high latitude cause a variety of sleep-related problems. Studies in the north of Norway and on Svalbard, at 80 degrees north, have demonstrated the occurrence of insomnia, an inability to fall asleep, repeated waking during the night, and the lack of feeling rested in the morning (Husby & Lingjærde, 1990; Nilssen et al., 1997). Similarly, for eating problems, the dark polar winter appears to cause eating disturbances in a significant proportion of the population at high latitude, with a common



symptom being overeating of carbohydrates (e.g., Perry, Silvera, Rosenvinge, Neilands, & Holte, 2001). LATITUDE AND COGNITION

There has been relatively little examination of the effects of the seasons on cognition in normal individuals. Taylor and Duncum (1987) reported that, among a sample spending the winter in Antarctica, there were no observed deficits on objective tests of cognitive performance, although there were selfreports of mental sluggishness. Brennen, Martinussen, Hansen, and Hjemdal (1999) investigated whether cognition was cyclical in a nonclinical sample living at 69 degrees north, testing participants both in summer and winter on a wide range of cognitive tasks that included verbal memory, attention, and reaction times. They found that people actually demonstrated winter advantages in four of the tests and a winter disadvantage in only one test. Also, Brennen (2001) showed that these results were independent of gender and the proportion of one’s life lived in northern Norway. Furthermore, the four winter advantages were for simple online attentional processing tasks, with very little memory load. Therefore, the best current conclusion is that memory processing does not have an annual rhythm in normal individuals, whereas attentional processing has a weak annual rhythm, with an advantage in winter. SEASONALITY AND PERSONALITY

Murray, Hay, and Armstrong (1995) were the first to look for steady internal individual differences that may be associated with seasonality. With a sample of 258 Australian female twins, they found that self-reports of seasonality correlated positively with neuroticism. On the other hand, Gordon, Keel, Hardin, and Rosenthal (1999) administered a personality questionnaire to a sample of 45 SAD patients and found that neuroticism did not correlate with seasonality. However, by testing SAD patients, they restricted the range of seasonality to the upper end of the scale, thereby reducing the chances of finding a link between neuroticism and seasonality. In the present study, we also administered a personality questionnaire to our respondents to shed some light on this issue. The present sample is not selected on the basis of seasonality, and so on the basis of Murray et al.’s (1995) results, we predicted a negative association between seasonality and emotional stability (a factor that, in the questionnaire used here, is the converse of neuroticism). In sum, research on the psychology of high latitudes has produced counterintuitive evidence. There is at best weak evidence for a correlation of SAD



with latitude, and the vast majority of people living in polar regions have no serious problems with mood in winter. In terms of cognitive performance, the little available evidence suggests that cognition may be sharper in winter. On the other hand, sleeplessness is a common problem in the winter months at high latitudes. THE PRESENT STUDY

Widespread incorrect negative intuitions about polar life can have pejorative economic consequences for the Arctic. Businesses may be less inclined to invest, tourists may be unduly reluctant to visit, and, because no capital cities are located in the polar regions, residents of the Arctic may suffer from underinvestment as a result of distorted, incorrect beliefs among decision makers. An inappropriate belief that latitude correlates strongly with SAD prevalence tends to give a clinical diagnosis to a whole region, which is nontrivial considering that it is estimated that, worldwide, over 2 million people live north of the Arctic Circle. Consequently, it would be interesting to explore individual beliefs and perceptions about the effects of the annual changes on human performance. The present study investigated participants’ experience of seasonal swings in a range of cognitive, mood-related, and everyday behaviors. It explored the concept of seasonality by asking participants also to estimate what sort of seasonal swings are experienced by other people at the same latitude (51 degrees north) and by people living in the Arctic Circle (north of 66.5 degrees north). Furthermore, and this is where we come to the second use we make of the astronomical facts in the opening paragraph, we have noted informally that many people do not possess knowledge of basic facts about the solar system. In the absence of a firm grasp of astronomical knowledge, seasonal changes may seem more capricious, and this study investigated astronomical knowledge to see what relationship, if any, it has with beliefs about the psychology of the seasons. It is known that during the first years of schooling, children tend to offer an explanation of the day-night cycle consistent with their knowledge derived through observation that the sun and moon are above the Earth, that their movements cause day and night, and that the Earth is flat. Later, as they are taught the Copernican model of the Earth rotating around the sun, children’s explanations seem to be based on a combination of their intuitive model and the scientific one, and this occurs by the age of 11 or before (Diakidoy, Vosniadou, & Hawks, 1997; Roald & Mikalsen, 2001; Vosniadou & Brewer, 1992, 1994). The present study tested adults’ grasp of the implications of the Copernican model for Earth in conjunction with the Earth’s axis being at an angle to the path of the orbit.



METHOD PARTICIPANTS

One hundred and sixty people participated in this study, which was conducted between October and December, 2000. Participants were drawn from among undergraduate psychology students at Goldsmiths College, University of London, who took part to gain credits as part of their first-year undergraduate course requirements. Participants were also recruited from the general population of London. Their age ranged from 18 to 87, with a mean age of 31.9 (SD = 15.3); 47 were male (mean age = 39.4, SD = 17.1), and 113 were female (mean age = 28.7, SD = 13.3). PROCEDURE

The undergraduate psychology students were recruited using posters advertising the study on the university campus. The posters provided basic details about the study, including that it was an investigation of mood and cognition, and invited interested participants to sign up for one of the available time slots and to meet the researcher in a quiet room situated on the university campus. Before being asked for written consent, all participants were then told that the study would take about 45 minutes in total, that all information would be treated confidentially, and that they could withdraw from the study at any stage. They were then instructed to complete the battery of tests in the following order: Seasonal Pattern Assessment Questionnaire, followed by the Cognition, SAD, and Astronomy Questionnaire, and then the personality questionnaire. On completion of the questionnaires, participants were fully debriefed and given an information sheet giving an outline of the study, background information, and references for further information on the topic area. The remaining participants were recruited in public places in London, and questionnaires were either distributed by hand or sent out in packs with instructions on the order in which to complete them. Most of these questionnaires were not filled in immediately but were handed back later in person or sent back in the post. On receipt of the questionnaires, these participants were either debriefed in person or via e-mail. PSYCHOMETRICS

The battery of tests consisted of the Seasonal Pattern Assessment Questionnaire, a personality questionnaire, and two questionnaires developed for



this study that were specifically designed to look at annual seasonal psychological rhythms in self and others and to tap basic knowledge about the solar system. Seasonal Pattern Assessment Questionnaire. The Seasonal Pattern Assessment Questionnaire (Rosenthal et al., 1984) is a widely used instrument that can be self-administered and that retrospectively evaluates over the course of a year at what time people feel at their worst and best, the degree to which such changes are perceived a problem, changes in dietary and sleep patterns, and the extent of seasonal variation in mood, appetite, weight, sleep, energy, and socialization. These six latter scales provide the Global Seasonality Score (GSS), ranging from 0 to 24: the higher the score, the greater the degree of seasonal change. Rosenthal’s (1998) version of the Seasonal Pattern Assessment Questionnaire was used in this study. Seasonal psychological changes in self and others. We compiled a questionnaire to examine seasonal psychological changes in the sample in domains such as cognitive, emotional, physical, and social functioning. It also examined beliefs about the effect of the seasons on the functioning of others living in London and of people living in the Arctic. For each attribute, participants were asked whether they noticed any seasonal changes (no change, slight change, moderate change, marked change, extremely marked change), at what time of the year the change occurred, and if it was a positive or negative change. Knowledge of SAD. The next part of the questionnaire consisted of multiple-choice questions and assessed participants’ knowledge of SAD. SAD knowledge was calculated by the number of correct responses to these questions, and each respondent was given a score out of five. Knowledge of astronomy. The final part of the questionnaire consisted of 10 multiple-choice questions about astronomical knowledge, with the correct answer and three distracters. More specifically, the questions tested knowledge of the relationship between the Earth, the sun, and the seasons. Astronomical score was calculated by the number of correct responses out of ten. The Five Factor Personality Inventory (FFPI). The FFPI consists of 100 questions shown to measure five personality dimensions: extraversion, agreeableness, conscientiousness, emotional stability, and autonomy. Each scale appears to be stable, valid, and internally consistent (Goldberg, 1990;



Hendriks, Hofstee, & de Raad, 1999). This instrument consists of 100 items. Respondents rate on 5-point scales the degree to which each is applicable to them, and each of the five personality dimensions is measured by 20 items.

RESULTS DEMOGRAPHIC CHARACTERISTICS

The sample’s education level and occupation status are presented in Table 1. PREVALENCE OF SAD, S-SAD, AND GSS

Using Kasper, Rogers, et al.’s (1989) and Kasper, Wehr, et al.’s (1989) criteria, the proportion of participants with SAD was 4.4%, made up of 6 females and 1 male. A further 24 (15%) had S-SAD, a group that was composed of 4 males (9%) and 20 females (18%). The remaining 129 (81%) did not report problematic seasonal changes, and there was no report of summer SAD. Diagnosis by questionnaire may well lead to overestimation of SAD rates, and on the basis of these prevalence data, we wish only to claim that this sample is within normal range of what might be expected in a general population. Although seasonality appeared stronger in women, a chi-square test revealed no significant gender differences in SAD status, χ2(2) = 3.27, p = .195. Of those qualifying for a diagnosis of SAD, the mean age was 37.86 (SD = 13.2), and the mean age for S-SAD was 28.33 (SD = 9.2). The mean overall GSS was 9.23 (Range = 1-24, SD = 5.1). This figure is higher than previous studies in Britain and similar latitudes (e.g., Eagles, Mercer, Boshier, & Jamieson, 1996; Mersch, Middendorp, Bouhuys, Beersma, & van den Hoofdakker, 1999a), where the mean GSSs were just under 6. As found previously (e.g., Eagles et al., 1996), females (M = 10.5, SD = 4.7) scored significantly higher than did males (M = 6.3, SD = 4.8, t(158) = 5.06, p < .001). KNOWLEDGE OF SAD

Affirmative responses were received from 134 (84%) of respondents to the following question: “Seasonal Affective Disorder (SAD) may be a subtype of depression in which individuals feel depressed in the winter, but


Brennen et al. / SEASONAL PSYCHOLOGICAL FLUCTUATIONS 229 TABLE 1 Participant Demographics

Demographic Education level No formal qualifications Left school at 16 Left school at 18 University graduate Postgraduate degree Occupation status Unemployed Retired Student Housewife Semiskilled Skilled Intermediate Professional

% 2 8 47 38 6 0.6 4 44 4 9 6 8 23

recover in the spring and summer. Have you heard of this disorder?” Females (88%) were more likely to have heard of the disorder than were males (72%), t(158) = 2.2, p < .029. There was general uncertainty about the underlying etiology of the disorder. Of the 26 people who had not heard of the disorder, half did not hazard a guess at the possible cause of SAD, and only 6 (23%) said it might be to do with light. Among those who had heard of it, 86 (64%) mentioned changes in the amount of sunlight and only 15 (11%) did not speculate about a cause. In line with the (limited) support for the latitude hypothesis, the majority of the sample identified that winter SAD would be less of a problem for those living at the equator (78%) and a greater problem for people living close to the North Pole (70%). Most of the sample correctly reported that women were more likely to suffer from the disorder (60%), with 36% guessing no difference between the sexes and with 4% guessing that men suffered more. Only 28% of the sample thought that people under 40 would suffer most from SAD, which is what the scientific literature in fact suggests, whereas 41% of the sample incorrectly believed that SAD was equally prevalent among all age groups. Finally, whereas 43% thought that SAD was a medical disorder, a fairly large proportion (30%) believed it was a social construction. Individuals’ SAD knowledge was calculated on their correct response to the five questions about SAD. The mean score for SAD knowledge was 3.02



(SD = 1.2). Females (M = 3.2, SD = 1.1) were more knowledgeable of the basic facts of SAD than were males (M = 2.7, SD = 1.3, t[158] = 2.23, p < .027). KNOWLEDGE OF ASTRONOMY

Individuals’ astronomical scores were calculated on their correct responses to the 10 remaining questions. The mean astronomical score, with chance giving an expected score of 2.5 out of 10, was 6.82 (SD = 2.3, range 110), with females (M = 6.32, SD = 2.2) demonstrating less knowledge of astronomy than males (M = 8.02, SD = 2.0, t[158] = 4.59, p < .001). The majority of participants correctly identified that (a) in England the length of days and nights are roughly the same during spring and autumn (71%); (b) the Earth rotating on its axis is responsible for day and night (67%); (c) it takes a year for the Earth to revolve around the sun (70%); (d) in summer the North Pole receives daylight 24 hours a day (64%); (e) the 21st of June is the shortest day in Australia (71%); (f) Australia is in the southern hemisphere (93%); (g) London is 51 degrees north rather than east, south, or west (60%); (h) midnight sun would mean there would be daylight 24 hours a day (71%); and during the two winter months in northern Norway there would be some daylight around noon (64%). Only 51% correctly identified that days and nights at the equator are of approximately the same length. RELATIONSHIP BETWEEN GSS, ASTRONOMICAL KNOWLEDGE, SAD KNOWLEDGE, PERSONALITY, AND EDUCATIONAL LEVEL

Knowledge of SAD was positively correlated with GSS (r = 0.21, p < .007), and this relationship remained significant when controlling for education (r = 0.19, p < .014). The Pearson correlation coefficient revealed a small but significant association between SAD knowledge and SAD status (r = 0.158, p < .047). Furthermore, the level of educational attainment was positively correlated with SAD knowledge, indicating that those with greater educational attainments had a greater knowledge of SAD (r = 0.157, p < .047). The amount of astronomical knowledge was positively correlated with educational achievements (r = .21, p < .001). There was no significant relationship between SAD status per se and astronomical knowledge (r = 0.07, p > .1), but GSS was negatively correlated with level of astronomical knowledge (r = –0.16, p < .038). The mean GSS for the 20 people who got all the astronomical questions correct was 7.2 (SD = 4.5). The mean GSS for the 14 people scoring 1, 2, or 3 on the test was 11.1 (SD = 2.9). Correct answers on 9



out of the 10 astronomical questions correlated negatively with GSS, whereas the other only correlated +0.02. There was no relationship between GSS and educational level (r = –0.11, p = 0.181). SAD knowledge and astronomical knowledge were positively correlated (r = 0.22, p < .02). Controlling for education, the relationship remained significant (r = 0.19, p < .05). To further explore the relationship among astronomical knowledge, SAD knowledge, and GSS, a multiple regression analysis was conducted. With education held constant, SAD knowledge was a significant predictor of GSS, t(2, 157) = 2.74, p < .01, explaining 4% of the variance in GSS. Adding astronomical knowledge increased the variance explained to 7%, F(3, 156) = 2.48, p < .05. For each participant, a score on the five personality dimensions measured by the FFPI (extraversion, agreeableness, conscientiousness, emotional stability, and autonomy) were calculated and then correlated with GSS. There was a significant negative correlation between emotional stability and GSS (r = –.19, p < .02) and a positive correlation between extraversion and GSS (r = .19, p < .02). PERCEPTION OF CHANGE IN PSYCHOLOGICAL FUNCTION IN SELF, OTHERS IN ENGLAND, AND OTHERS IN THE ARCTIC CIRCLE

Very few times did a participant claim annual variation in any attribute was other than slight or moderate. Separately for SAD-related attributes and cognitive attributes, Figure 1 presents a summary of the proportion of participants reporting no change and winter or summer advantages for themselves, for other Londoners, and for Arctic dwellers, collapsing over slight and moderate responses. For each of the three scales, alpha coefficients were calculated. To use scales of sufficient reliability, three items (general appetite, consumption of alcohol, and consumption of drugs) were excluded. The alpha coefficients for the resulting three scales were as follows: self = 0.72, other Londoners = 0.70, Arctic = 0.76. Correlations were calculated between perceptions of change in oneself and perceptions of change in other people living in London and the Arctic. Pearson correlation coefficients revealed significant relationships between self and others in England (r = 0.412, p < .001), between self and those in the Arctic (r = 0.312, p < .001), and between others in England and the Arctic (r = 0.475, p < .001). The three conditions for mediation were satisfied (Baron & Kenny, 1986), and so a mediation analysis was conducted to gain a more precise picture of



100

80

60

% of sample

40 No change

20

Summer advantage Winter advantage

0

ic ct Ar D s er SA on nd Lo D SA lf se D tic SA rc A s ve er iti on gn nd co Lo ve iti gn co lf se ve iti gn co

Figure 1: The Percentages of Participants Rating No Change or a Seasonal Advantage on Cognitive and SAD-Related Dimensions in Themselves, Other Londoners, and People Living in the Arctic

the relationship of self perceptions and perceptions of others on the perception of Arctic people. We hypothesized that perception of others would mediate the relation between self-perception and perception of Arctic people. There were significant relationships between self-perception and perception of Arctic people (the criterion) and self-perception and perception of others (the mediator). Regressing perception of Arctic people on both selfperceptions and perception of others yielded a nonsignificant beta for selfperceptions (β =.14, t = 1.8, p > .05) and a significant beta for perceptions of others, (β =.42, t = 5.4, p < .05). Therefore, in this sample, respondents based their ideas about those in the Arctic primarily on how they think other people in England are affected by the seasons, which is again based on how they themselves are affected.

DISCUSSION

This study explored participants’ reports of seasonal psychological fluctuations and their personality, their knowledge of SAD, and their knowledge of basic astronomy. The results demonstrated links among seasonality,



personality, and knowledge of SAD and astronomy. They also showed that people retain inaccurate beliefs about the physical environment and its potential effect on human functioning. Performance on the test of astronomical knowledge correlated negatively with GSS, which raises the interesting possibility that knowledge of the Earth-sun system in some way protects against seasonal mood swings, perhaps by providing an explanation for winter’s relatively dark and cold environment as well as assurance that it will soon be replaced by spring. Knowledge about SAD, unlike astronomical knowledge, correlated positively with GSS. Possibly, greater knowledge of SAD assists people in the identification and classification of symptoms, which increases the likelihood of report. Alternatively, learning more about SAD may actually cause people to be more likely to experience and report the symptoms, or experiencing strong seasonality may lead people to seek out more information about SAD. Our data are consistent with Murray et al.’s (1995) report of a link between neuroticism and the tendency to worse emotional functioning in winter. The question of causality remains open, and two possibilities suggest themselves to us. Firstly, it may be that high scorers on neuroticism have a tendency toward more self-report of winter mood swings, possibly as part of a tendency to report more of both ailments. Secondly, and not mutually exclusively, Gordon et al. (1999) point out that there is a genetic locus that has been implicated in both SAD and neuroticism, which opens the possibility that the two measures are linked by a common cause. This will be an interesting topic for future research. In this context, it is interesting to note that staff who are selected to winter over on polar research stations are significantly lower on neuroticism than are control participants (Steel, Suedfeld, Peri, & Palinkas, 1997). Furthermore, in our data, GSS also correlated positively with extraversion. This builds up a picture of high GSS scorers as emotionally labile extroverts who know less than average about the physical causes of the annual cycle on Earth but more than average about the condition of SAD. There were some interesting patterns in perceived swings in psychological functioning in oneself compared to those perceived in others and those assumed in Arctic dwellers. The mediation analysis suggested that people base their predictions of how the behavior of others at the same latitude varies over the annual cycle on the ratings of their own swings and in turn base the predictions about life in the Arctic on their predictions of others. On the cognitive attributes, there was very little difference between the seasonal swings participants reported for themselves and those they predicted for others, even those living in the Arctic Circle. This is consistent with



the available evidence from cognitive psychology that suggests there is little seasonal variation in cognitive performance. For the SAD-related attributes, few thought mood would be better in winter, and the most frequent response was that there would be no general seasonal change in mood, consistent with the growing consensus in the scientific literature that season does not have a big effect on mood. On the other hand, inconsistent with the literature on seasonal eating patterns in the Arctic, although almost half the participants thought there was an increase in appetite in winter for themselves and others in London, only 7% thought there was a similar increase for Arctic dwellers. Another misunderstanding of the effect of the Arctic environment on humans was found in the questions on sleep. During the polar winter, there is evidence that sleep patterns become disturbed: People sleep longer, and the sleep is of lower perceived quality. However more participants predicted this pattern for Londoners than for Arctic people. Generally, however, our sample did not have unduly pessimistic ideas about mental life north of the Arctic Circle, which from the Arctic perspective is an uplifting conclusion. Consistent with the scientific evidence, the modal response was for no seasonal variation in cognition or mood. Indeed, just under half the sample said that there would not even be mood swings over the annual cycle for people living in the Arctic. Other behaviors were assumed to have similar sorts of swings in the Arctic as at London’s latitude. Conversely, the sample as a whole failed to predict the well-established disturbances of sleep and eating during the Arctic winter. The study also strengthened the link between personality and seasonality: Highly seasonal people were low on emotional stability and high on extraversion. Furthermore, seasonality correlated negatively with astronomical knowledge and positively with SAD knowledge.

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