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Wang MQ, Hao Y, Wang RR, Guo H, He J, Wang ZR. Is being born in spring significantly associated with early-onset bipolar affective disorder? A case-control study. Chronobiol Int 2021; 37:1644-1649. [PMID: 33297785 DOI: 10.1080/07420528.2020.1764013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Few studies have investigated relationships between birth season and early-onset bipolar affective disorder (BAD) in young adults. In the current study, birth season was compared in patients with early-onset BAD and in sex-matched and age-matched controls. A total of 957 patients aged <25 years of age from three hospitals in the North China Plain region were enrolled in the study. Sex-matched and age-matched control group data were collected in universities and schools via questionnaires. The R*C chi-square test was used to assess distributional differences in season of birth both in the patient and control group. A binary logistic regression model adjusted for age and sex was used to evaluate associations between season of birth and BAD. Using spring as the reference season, BAD patients showed significantly lower odds ratios of being born in any other season. There were associations between birth season and early-onset BAD, and early-onset BAD patients were more likely to have been born in spring. These data have implications for future disease prevention strategies and future research.
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Affiliation(s)
- Meng-Qi Wang
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine , Beijing, China
| | - Yu Hao
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine , Beijing, China
| | - Ran-Ran Wang
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine , Beijing, China
| | - Hua Guo
- Department of psychiatry, The Psychiatric Hospital of Zhumadian , Zhumadian City, Henan province, China
| | - Juan He
- School of Traditional Chinese Medicine, Beijing University of Chinese Medicine , Beijing, China
| | - Zhi-Ren Wang
- Psychiatry research center, Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School , Beijing, China
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Lee H, Lee HK, Lee K. Is personality linked to season of birth? PLoS One 2021; 16:e0253815. [PMID: 34170954 PMCID: PMC8232405 DOI: 10.1371/journal.pone.0253815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 06/11/2021] [Indexed: 11/19/2022] Open
Abstract
The environment is a very significant factor in early childhood development. Season of birth (SOB) is a proxy viable for the environment to which the babies are exposed, thus also significant in early development. This study investigates the association between SOB and personality. A total 2,962 college students were included as study participants. The participants were classified into four seasonal groups based on their birth month and underwent a personality assessment using the Temperament and Character Inventory (TCI). Statistical analysis was performed using one-way analysis of variance (ANOVA) and multinomial logistic regression analysis. The male participants born in autumn scored high on the Disorderliness (NS4) subscale (β = 0.055, P = 0.042) and the male participants born in summer and winter scored high on the Extravagance (NS3) subscale (summer: β = 0.072, P = 0.01, winter: β = 0.078, P = 0.003). The difference observed indicates a relationship between the SOB and temperament, especially NS. Our findings suggest that environmental factors may affect temperament in early development, although further research is likely needed to clarify the causality between them.
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Affiliation(s)
- Hoseon Lee
- Seodaemoonbom Psychiatric Clinic, Seoul, Republic of Korea
- Department of Psychiatry, College of Medicine, Hanyang University, Seoul, Republic of Korea
| | - Hye-Kyung Lee
- Department of Nursing, College of Nursing and Health, Kongju National University, Gongju, Republic of Korea
| | - Kounseok Lee
- Department of Psychiatry, College of Medicine, Hanyang University, Seoul, Republic of Korea
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Chotai J, Jonasson M, Hägglöf B, Adolfsson R. Adolescent attachment styles and their relation to the temperament and character traits of personality in a general population. Eur Psychiatry 2020; 20:251-9. [PMID: 15935425 DOI: 10.1016/j.eurpsy.2004.11.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2004] [Accepted: 11/01/2004] [Indexed: 11/23/2022] Open
Abstract
AbstractAttachment styles as well as personality traits in adolescents and adults have been found to be associated with their health outcomes and with their personality pathology. In this cross-sectional exploratory study, we study the relationship between attachment styles that derive from our data employing the items of Feeney et al. (1994) self-report attachment style questionnaire (ASQ), and personality traits given by the junior version of Cloninger et al. (1993) self-report temperament and character inventory (TCI), in a sample of 426 adolescents (54% females) from a general population. The secure attachment style was correlated significantly negatively with the personality trait harm avoidance (HA), but significantly positively with the personality traits novelty seeking (NS), reward dependence (RD), cooperativeness (CO) and self-transcendence (ST). The preoccupied (anxious/ambivalent) attachment style was correlated significantly positively with HA and NS, but significantly negatively with self-directedness (SD). The fearful-avoidant category was correlated significantly negatively with NS. Our five-factor solution of the attachment styles and their relation to the TCI point towards a need for a modification of the two-axis, four-category attachment model of Bartholomew (1990) and Bartholomew and Horowitz (1991), with their category dismissing-avoidant replaced by the two categories defined here as dismissing relations (correlated significantly negatively with CO) and dismissing others (correlated significantly negatively with RD and significantly positively with SD).
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Affiliation(s)
- Jayanti Chotai
- Division of Psychiatry, Department of Clinical Sciences, University Hospital, University of Umeå, 901 85 Umeå, Sweden.
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Alfimova MV, Golimbet VE, Korovaitseva GI, Lezheiko TV, Kondrat'ev NV, Gabaeva MV. [Effect of cytokine genes and season of birth on personality]. Zh Nevrol Psikhiatr Im S S Korsakova 2018; 117:82-87. [PMID: 29053126 DOI: 10.17116/jnevro20171179182-87] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
AIM To evaluate the interaction effects of season of birth and immune system genes on the personality traits 'Novelty seeking' (NS) and 'Self-directedness' (SD). Based on results on an influence of the immune system on the brain processes, the authors hypothesized that the interaction of immune system genes and season of birth, which is relevant for immune phenotype, can contribute to the development of personality traits. MATERIAL AND METHODS NS and SD were measured in 336 healthy volunteers, aged from 16 to 67 years, using the Temperament and Character Inventory (TCI-125). IL1B C3954T, IL4 C-589T, IL13 C1112T and TNFA G-308A polymorphisms were genotyped. RESULTS An interaction effect of IL4 C-589T and season of birth on the personality traits was found (F2,322=6.03, pcorr=0.011, η2=0.04). Carriers of the minor allele T, who were born in winter, had lower NS and higher SD. There was a nominal main effect of genotype on SD (F=5.44, p=0.020) as well, with higher SD scores in carriers of the allele T compared to the CC genotype. CONCLUSION The results suggest that the etiology of personality and immune characteristics can share common genetic elements including IL-4.
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Affiliation(s)
| | | | | | | | | | - M V Gabaeva
- Mental Health Research Center, Moscow, Russia
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5
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Asano R, Tsuchiya KJ, Harada T, Kugizaki Y, Nakahara R, Nakayasu C, Okumura A, Suzuki Y, Takagai S, Mori N, Takei N. Season of Birth Predicts Emotional and Behavioral Regulation in 18-Month-Old Infants: Hamamatsu Birth Cohort for Mothers and Children (HBC Study). Front Public Health 2016; 4:152. [PMID: 27504441 PMCID: PMC4958653 DOI: 10.3389/fpubh.2016.00152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 07/08/2016] [Indexed: 12/04/2022] Open
Abstract
Background Previous research has demonstrated that the season of birth may predict development of emotional and behavioral regulation during childhood or adolescence. This study examined whether the season of birth predicts effortful control (i.e., the ability to voluntarily choose course of actions during conflict and to plan for the future) and aggression (i.e., the use of physical force and expression of anger toward others) in 18-month-old infants. Methods Participants included 885 infants who were enrolled in the Hamamatsu Birth Cohort for Mothers and Children in Hamamatsu, Japan. Seasons of birth were categorized into winter (December, January, and February), spring (March, April, and May), summer (June, July, and August), and autumn (September, October, and November). At 18 months of age, effortful control was assessed using the Early Childhood Behavior Questionnaire, and aggression was measured using the Cardiff Infant Contentiousness Scale. Structural equation modeling analysis with measurement and structural equations was conducted to test our prediction. Results Effortful control was higher in infants born in spring [B = 0.095, 95% CI (0.014 to 0.175), p = 0.021, β = 0.146] and summer [B = 0.078, 95% CI (0.001 to 0.156), p = 0.049, β = 0.118] than in those born in winter. In addition, aggression was lower in those born in spring [B = −0.286, 95% CI (−0.551 to −0.021), p = 0.035, β = −0.135] than those born in winter, even after controlling for seven covariates. Conclusion The findings suggest that season of birth may determine development of emotional and behavioral regulation skills during early infancy. Future research should pay more attention to the underlying mechanisms of the effects of birth season on development of emotional and behavioral regulation during infancy.
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Affiliation(s)
- Ryosuke Asano
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan
| | - Kenji J Tsuchiya
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan
| | - Taeko Harada
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Yumeno Kugizaki
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Ryuji Nakahara
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Chikako Nakayasu
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Akemi Okumura
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Yukiko Suzuki
- Research Center for Child Mental Development, Hamamatsu University School of Medicine , Hamamatsu , Japan
| | - Shu Takagai
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan
| | - Norio Mori
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan; Department of Psychiatry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Nori Takei
- Research Center for Child Mental Development, Hamamatsu University School of Medicine, Hamamatsu, Japan; Department of Child Development, United Graduate School of Child Development, Osaka University, Kanazawa University, Hamamatsu University School of Medicine, Chiba University and University of Fukui, Hamamatsu, Japan; Division of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK
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6
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Abstract
Humans exhibit seasonal variation in a wide variety of behavioral and physiological processes, and numerous investigators have suggested that this might be because we are sensitive to seasonal variation in day length. The evidence supporting this hypothesis is inconsistent. A new hypothesis is offered here—namely, that some humans indeed are seasonally photoresponsive, but others are not, and that individual variation may be the cause of the inconsistencies that have plagued the study of responsiveness to photoperiod in the past. This hypothesis is examined in relation to seasonal changes in the reproductive activity of humans, and it is developed by reviewing and combining five bodies of knowledge: correlations of human birthrates with photoperiod; seasonal changes in the activity of the neuroendocrine pathway that could link photoperiod to gonadal steroid secretion in humans; what is known about photoperiod, latitude, and reproduction of nonhuman primates; documentation of individual variation in photoresponsiveness in rodents and humans; and what is known about the evolutionary ecology of humans.
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Affiliation(s)
- F H Bronson
- Center for Behavioral Neuroendocrinology, University of Texas at Austin, 78712, USA.
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7
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Kulendran M, Vlaev I, Sugden C, King D, Ashrafian H, Gately P, Darzi A. Neuropsychological assessment as a predictor of weight loss in obese adolescents. Int J Obes (Lond) 2013; 38:507-12. [PMID: 24166064 DOI: 10.1038/ijo.2013.198] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 09/28/2013] [Accepted: 10/15/2013] [Indexed: 01/10/2023]
Abstract
BACKGROUND Obese individuals are known to be more impulsive than their normal-weight counterparts. Impulsivity has been postulated to be a predictor of weight loss. DESIGN A pre-post study was designed to determine for the first time whether impulsivity changed with weight loss during a lifestyle and physical activity intervention programme lasting 2-8 weeks. SUBJECTS Fifty-three obese adolescents with a body mass index (BMI) of 33.75 ± 7.9 attending a residential camp were tested and compared at baseline with 50 non-obese adolescents with a mean BMI of 20.6 ± 2.3. MEASUREMENTS Inhibitory control was measured with the CANTAB (Cambridge Cognition, Cambridge, UK) Stop Signal Task. MATLAB (The Mathswork Inc., Natick, MA, USA) was used to measure the temporal discounting constant. RESULTS The obese group was more impulsive than the normal weight adolescents. BMI reduced significantly from 33.76 kg m(-2) to 30.93 kg m(-2) after completing camp. The stop signal reaction time (SSRT) decreased from 225.38 ± 94.22 to 173.76 ± 107.05 ms (n=47, P=0.0001). A reduction in inhibitory control during camp was predictive of those who showed the greatest reduction in BMI (Wilks' Lambda=0.9, F(1,50)=4.85, P=0.034). The number of weeks in camp (Wilks' Lambda=0.83, F(1,50)=9.826, P=0.003) and the age of the adolescents (Wilks' Lambda=0.87, F(1,50)=5.98, P=0.02) were significantly associated with a reduction in inhibitory control as measured by the SSRT. A longer stay in camp was associated with a greater reduction in SSRT (B=25.45, t=2.02, P=0.05). Increasing age had a significant moderating role in the reduction of inhibitory control (B=-0.3, t=-0.034, P=0.05). Temporal discounting for monetary reward also fell significantly during camp. CONCLUSION This study highlights the potential to identify those who are obese by using an easy-to-measure psychometric test. Furthermore, it is the first study to report a reduction in impulsivity and an improvement in well-being as part of a government-approved residential camp for obese adolescents. The potential mechanisms for change in impulsivity with weight are discussed.
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Affiliation(s)
- M Kulendran
- Centre for Health Policy, Imperial College London, London, UK
| | - I Vlaev
- Centre for Health Policy, Imperial College London, London, UK
| | - C Sugden
- Centre for Health Policy, Imperial College London, London, UK
| | - D King
- Centre for Health Policy, Imperial College London, London, UK
| | - H Ashrafian
- Centre for Health Policy, Imperial College London, London, UK
| | - P Gately
- 1] Centre for Health Policy, Imperial College London, London, UK [2] Department of Exercise and Obesity, Leeds Metropolitan University, Leeds, UK
| | - A Darzi
- Centre for Health Policy, Imperial College London, London, UK
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8
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Winje E, Torgalsbøen AK, Brunborg C, Lask B. Season of birth bias and anorexia nervosa: results from an international collaboration. Int J Eat Disord 2013; 46:340-5. [PMID: 23070973 DOI: 10.1002/eat.22060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/08/2012] [Indexed: 01/21/2023]
Abstract
OBJECTIVE Based on inconsistent findings in the literature, this study tested the hypothesis that "there is a season of birth bias for females with anorexia nervosa (AN)." METHOD Females with AN, born in 1975 to 1996, were compared to females born in the same years and geographical regions by chi-square test for contingency tables with known population parameter testing for monthly deviations. Five groups were based on a priori power calculation and geographical location: Iceland, Norway and Sweden (N = 847), United Kingdom (N = 706), Oregon, USA (N = 394), Argentina and Brazil (N = 486), and Australia (N = 381). RESULTS The hypothesis was not supported in any of the groups. The associations (Cramér's V) between month of birth and the differences in distributions of births ranged from 0.05 to 0.08, none of which were statistically significant. DISCUSSION The main implication of these findings is that season of birth may not play a significant part in the aetiology of AN.
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Affiliation(s)
- Eirin Winje
- Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.
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9
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Winje E, Torgalsbøen AK, Brunborg C, Lask B. Season of Birth Bias and Bulimia Nervosa-Results from a Multi-centre Collaboration. EUROPEAN EATING DISORDERS REVIEW 2013; 21:170-4. [DOI: 10.1002/erv.2217] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Eirin Winje
- Oslo University Hospital; Regional Department for Eating Disorders; Oslo; Norway
| | | | - Cathrine Brunborg
- Oslo University Hospital; Unit for Biostatistics and Epidemiology; Oslo; Norway
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Gonda X, Fountoulakis KN, Csukly G, Dome P, Sarchiapone M, Laszik A, Bedi K, Juhasz G, Siamouli M, Rudisch T, Molnar E, Pap D, Bagdy G, Rihmer Z. Star-crossed? The association of the 5-HTTLPR s allele with season of birth in a healthy female population, and possible consequences for temperament, depression and suicide. J Affect Disord 2012; 143:75-83. [PMID: 22840619 DOI: 10.1016/j.jad.2012.05.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 05/29/2012] [Accepted: 05/29/2012] [Indexed: 12/20/2022]
Abstract
BACKGROUND Birth season has well-known effects on neuropsychiatric disorders, and may also influence genotype distribution by possibly influencing chance of conception via parental idiosyncratic conception patterns or survival of foetuses or infants. The 5-HTTLPR is associated with phenomena including affective temperaments or suicide which are also associated with birth season. Our aim was to investigate the association of 5-HTTLPR genotype and birth season in a healthy female population. METHODS Birth date and 5-HTTLPR genotype was determined for 327 psychiatrically healthy women. The association between presence of s allele and time of birth was analysed using generalized linear models. RESULTS A significant association between s allele frequency and time of birth was detected. S allele carrier frequency was marginally significantly higher in July borns and significantly lower in autumn borns. LIMITATIONS We investigated an adult sample so genotype frequency data do not reflect birth frequencies. Our sample consisted exclusively of females. CONCLUSIONS There is no clear explanation for the observed association, although idiosyncratic parental conception patterns, the association of 5-HTTLPR with sudden infant/intrauterine death, or other s allele-mediated behaviours may play a role. Our results are strikingly parallel with earlier data reporting a higher risk of completed suicide in July borns, and higher scores of July borns and lower scores of autumn borns on certain affective temperament scales, both of which are also associated with the s allele of 5-HTTLPR. Thus our results may add to the growing body of evidence regarding the etiological background of affective disorders.
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Affiliation(s)
- Xenia Gonda
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University, Budapest, Hungary.
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11
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Hori H, Teraishi T, Sasayama D, Matsuo J, Kawamoto Y, Kinoshita Y, Kunugi H. Relationships between season of birth, schizotypy, temperament, character and neurocognition in a non-clinical population. Psychiatry Res 2012; 195:69-75. [PMID: 21824667 DOI: 10.1016/j.psychres.2011.07.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 07/13/2011] [Accepted: 07/16/2011] [Indexed: 10/17/2022]
Abstract
While schizophrenia has been associated with a slight excess of winter/early spring birth, it is unclear whether there is such an association in relation to schizotypal personality traits. Season of birth has also been reported to relate to temperament and character personality dimensions and cognitive functioning. Moreover, non-clinical schizotypy has been shown to be associated with mild cognitive impairment, although its precise nature is yet to be elucidated. Here we examined the relationships between season of birth, schizotypal traits, temperament and character, and cognitive function. Four hundred and fifty-one healthy adults completed the Schizotypal Personality Questionnaire (SPQ). The Temperament and Character Inventory (TCI) and a neuropsychological test battery consisting of full versions of the Wechsler Memory Scale-Revised and the Wechsler Adult Intelligence Scale-Revised, and the Wisconsin Card Sorting Test, were also administered to most of the participants. The total SPQ score of those born in winter was significantly higher than that of the remaining participants. Season of birth was not significantly associated with any of the TCI dimensions or cognitive test results. Significant but mild relationships between higher SPQ scores and lower scores on some aspects of IQ were observed. These results support the notion that schizotypy and schizophrenia are neurodevelopmental conditions on the same continuum.
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Affiliation(s)
- Hiroaki Hori
- Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan.
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12
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Rihmer Z, Erdos P, Ormos M, Fountoulakis KN, Vazquez G, Pompili M, Gonda X. Association between affective temperaments and season of birth in a general student population. J Affect Disord 2011; 132:64-70. [PMID: 21334071 DOI: 10.1016/j.jad.2011.01.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Revised: 01/25/2011] [Accepted: 01/25/2011] [Indexed: 10/18/2022]
Abstract
BACKGROUND Several studies indicate a significant association between birth season and personality and neuropsychiatric disorders. The aim of our present study was to investigate the association between affective temperaments and season of birth in a nonclinical sample. METHODS 366 university students completed the standardized Hungarian version of the Temperament Evaluation of Memphis, Pisa, Paris and San Diego-Auto-questionnaire (TEMPS-A). Ordinary Least Squares regression was applied to explain the relationship between TEMPS-A subscale and birth season of the respondents. RESULTS We found a significant association between temperament scores and birth season in the case of the Hyperthymic, Cyclothymic, Irritable and Depressive temperaments, while no significant results emerged for the Anxious temperament. LIMITATIONS The relatively small sample size, especially in the case of seasonal and monthly subsamples limits generalization of our results. CONCLUSIONS Our results support the evidence that there is a strong association between season of birth and personality, extending the results to affective temperaments as well. Furthermore, our results are in line with clinical observations concerning the seasonal variation of onset and hospitalization due to affective episodes. This is especially important, since affective temperaments are conceived as the subaffective and subclinical manifestations of major and minor affective disorders indicating a risk for the development of these disorders and also exerting a possible pathoplastic effect, thus our results also have clinical significance.
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Affiliation(s)
- Zoltan Rihmer
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University; Kutvolgyi ut 4., 1125 Budapest, Hungary.
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Roussos P, Giakoumaki SG, Bitsios P. Cognitive and emotional processing associated with the Season of Birth and dopamine D4 receptor gene. Neuropsychologia 2010; 48:3926-33. [PMID: 20875435 DOI: 10.1016/j.neuropsychologia.2010.09.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 09/14/2010] [Accepted: 09/17/2010] [Indexed: 01/16/2023]
Abstract
The 7-repeats variant of the dopamine D4 receptor (7R) VNTR polymorphism has been associated with higher novelty seeking (NS) and disadvantageous decision making in the Iowa Gambling Task (IGT). Season of Birth (SOB) is a significant determinant of NS. SOB and L-DRD4 genetic polymorphism may independently and interactively influence similar behaviors through their common effects on the dopaminergic system. Two hundred and twenty-seven healthy males grouped in summer-born/4-repeats (4R) (n=75), winter-born/4R (n=90), summer-born/7R (n=31) and winter-born/7R (n=31) groups, completed multimodal assessment for personality, planning for problem solving and decision making. Winter-born/7R subjects had significantly worse IGT performance throughout the task compared to 4R individuals, while summer-born 7R subjects had intermediate, although not significantly different performance. Moreover, winter-born/7R subjects had increased behavioral approach to reward without parallel reduction in sensitivity to fear or to social approval cues. The DRD4-by-SOB groups did not differ in planning for problem solving. These results suggest that a DRD4-by-SOB interaction is associated with increased behavioral approach to reward and risk taking but efficient problem solving. In addition, these results further support the hypothesis that SOB modifies the behavioral expression of dopaminergic genetic polymorphism. SOB should be included in future studies of risky behaviors and behavioral genetic studies of the dopamine system.
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Affiliation(s)
- Panos Roussos
- Department of Psychiatry and Behavioral Sciences, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece
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14
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Chotai J, Joukamaa M, Taanila A, Lichtermann D, Miettunen J. Novelty seeking among adult women is lower for the winter borns compared to the summer borns: replication in a large Finnish birth cohort. Compr Psychiatry 2009; 50:562-6. [PMID: 19840595 DOI: 10.1016/j.comppsych.2008.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2008] [Revised: 11/06/2008] [Accepted: 11/16/2008] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Earlier general population studies have shown that novelty seeking (NS) of the Temperament and Character Inventory (TCI) of personality is lower for persons born in winter compared to those born in summer, particularly for women. Here, we investigate if this result can be replicated in another population. METHOD The Northern Finland 1966 Birth Cohort, comprising 4968 subjects (2725 women, 2243 men), was investigated with regard to the temperament dimensions of the TCI and the season of birth. RESULTS Novelty seeking and reward dependence (RD) showed significant variations according to the month of birth. We found that women born during winter have significantly lower levels of NS compared to women born during summer, with a minimum for the birth month November and maximum for May. These results are similar to those found in a previous Swedish study. Furthermore, our study showed that men born during spring had significantly lower mean scores of RD compared to men born during autumn, with a minimum for birth month March. This was in contrast to the Swedish study, where the minimum of RD was obtained for the birth month December. CONCLUSION Women born in winter have lower NS as adults compared to women born in summer. Because NS is modulated by dopamine, this study gives further support to the studies in the literature that show that dopamine turnover for those born in winter is higher than for those born in summer.
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Affiliation(s)
- Jayanti Chotai
- Division of Psychiatry, Department of Clinical Sciences, University of Umeå, 901 85 Umeå, Sweden.
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15
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Season of birth and personality in healthy young adults. Neurosci Lett 2009; 452:185-8. [DOI: 10.1016/j.neulet.2009.01.055] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 01/09/2009] [Accepted: 01/23/2009] [Indexed: 11/20/2022]
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Asch M, Cortese S, Perez Diaz F, Pelissolo A, Aubron V, Orejarena S, Acquaviva E, Mouren MC, Michel G, Gorwood P, Purper-Ouakil D. Psychometric properties of a French version of the junior temperament and character inventory. Eur Child Adolesc Psychiatry 2009; 18:144-53. [PMID: 19198924 DOI: 10.1007/s00787-008-0713-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Accepted: 06/18/2008] [Indexed: 11/24/2022]
Abstract
The junior temperament and character inventory (JTCI) has been developed for the assessment of temperament and character dimensions in childhood based on Cloninger's model of personality. We evaluated the psychometric proprieties of a French child and parent-rated version of the JTCI based on a previous German version, and assessed the correlations between the JTCI dimension scores and the scores on the child behavior checklist (CBCL) in a community sample of French children and adolescents aged 10-16 years. We used data from 452 child-rated and 233 -parent-rated JCTI. The psychometric properties (internal consistency and external validity in relation to the emotionality activity sociability (EAS) questionnaire) of the French JTCI were adequate in the parent-rated version. The parent-rated JTCI had overall better psychometric qualities than the child-rated version, but for both versions of the JTCI the confirmatory factor analysis showed low fit between the observed data and the original model. Dimensions of the EAS model were significantly correlated with the temperament scales of the JTCI. Further studies are required to improve the psychometric properties of the child-rated JTCI, and to provide insight about lacking fit of our data with the theoretical model.
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Affiliation(s)
- M Asch
- AP-HP, Service de Psychopathologie de l'Enfant et de l'Adolescent, Hôpital Robert Debré, Paris, France
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17
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Kamata M, Suzuki A, Matsumoto Y, Togashi H, Otani K. Effect of month of birth on personality traits of healthy Japanese. Eur Psychiatry 2008; 24:86-90. [PMID: 19070993 DOI: 10.1016/j.eurpsy.2008.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Revised: 10/22/2008] [Accepted: 10/24/2008] [Indexed: 10/21/2022] Open
Abstract
The effect of month of birth on personality traits was investigated in 595 healthy Japanese. Personality traits were evaluated by the Temperament and Character Inventory (TCI). Statistical analyses were conducted in two steps. Firstly, months of the year were divided according to ambient temperature or photoperiod, and TCI scores were compared between month groups by analysis of covariance (ANCOVA) with age as a covariate. Secondly, multiple regression analysis was performed with TCI scores as dependent variables and ambient temperature and photoperiod at birth month and age as independent variables. Both analyses showed that higher ambient temperature at birth month was related to higher scores of self-directedness and persistence in females. Also, higher ambient temperature at birth month was related to lower body mass index (BMI) in females. These results suggest that month of birth affects self-directedness and persistence in healthy Japanese females, and these effects may be mediated by BMI changes associated with ambient temperature at birth month.
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Affiliation(s)
- Mitsuhiro Kamata
- Health Administration Center, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan.
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Abdel-Khalek AM. Month and Season of Birth are Not Associated with Extraversion and Neuroticism in an Egyptian Sample. Psychol Rep 2008; 102:870-2. [DOI: 10.2466/pr0.102.3.870-872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In a sample of 828 (383 men and 445 women) Egyptian undergraduates ( M age = 19.6 yr., SD=1.7), scores on Extraversion and Neuroticism scales of the Eysenck Personality Questionnaire were neither associated with the month nor the season of birth.
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19
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Eisenberg DTA, Campbell B, Mackillop J, Lum JK, Wilson DS. Season of birth and dopamine receptor gene associations with impulsivity, sensation seeking and reproductive behaviors. PLoS One 2007; 2:e1216. [PMID: 18030347 PMCID: PMC2075470 DOI: 10.1371/journal.pone.0001216] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Accepted: 09/14/2007] [Indexed: 12/02/2022] Open
Abstract
Background Season of birth (SOB) has been associated with many physiological and psychological traits including novelty seeking and sensation seeking. Similar traits have been associated with genetic polymorphisms in the dopamine system. SOB and dopamine receptor genetic polymorphisms may independently and interactively influence similar behaviors through their common effects on the dopaminergic system. Methodology/Principal Findings Based on a sample of 195 subjects, we examined whether SOB was associated with impulsivity, sensation seeking and reproductive behaviors. Additionally we examined potential interactions of dopamine receptor genes with SOB for the same set of traits. Phenotypes were evaluated using the Sociosexual Orientation Inventory, the Barratt Impulsivity Scale, the Eysenck Impulsivity Questionnaire, the Sensation Seeking Scale, and the Delay Discounting Task. Subjects were also asked about their age at first sex as well as their desired age at the birth of their first child. The dopamine gene polymorphisms examined were Dopamine Receptor D2 (DRD2) TaqI A and D4 (DRD4) 48 bp VNTR. Primary analyses included factorial gender×SOB ANOVAs or binary logistic regression models for each dependent trait. Secondary analysis extended the factorial models by also including DRD2 and DRD4 genotypes as independent variables. Winter-born males were more sensation seeking than non-winter born males. In factorial models including both genotype and season of birth as variables, two previously unobserved effects were discovered: (1) a SOB×DRD4 interaction effect on venturesomeness and (2) a DRD2×DRD4 interaction effect on sensation seeking. Conclusion These results are consistent with past findings that SOB is related to sensation seeking. Additionally, these results provide tentative support for the hypothesis that SOB modifies the behavioral expression of dopaminergic genetic polymorphism. These findings suggest that SOB should be included in future studies of risky behaviors and behavioral genetic studies of the dopamine system.
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Affiliation(s)
- Dan T A Eisenberg
- Department of Anthropology, Northwestern University, Evanston, Illinois, United States of America.
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20
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Mandel Y, Grotto I, El-Yaniv R, Belkin M, Israeli E, Polat U, Bartov E. Season of birth, natural light, and myopia. Ophthalmology 2007; 115:686-92. [PMID: 17698195 DOI: 10.1016/j.ophtha.2007.05.040] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 05/21/2007] [Accepted: 05/21/2007] [Indexed: 11/30/2022] Open
Abstract
PURPOSE To investigate the possible roles of season of birth and perinatal duration of daylight hours (photoperiod) in the development of myopia. DESIGN Retrospective, population-based, epidemiological study. PARTICIPANTS A total of 276 911 adolescents (157 663 male, 119 248 female) 16 to 22 years old. All were Israeli-born conscripts to the Israeli Defense Forces who were examined during the 5-year period 2000 through 2004. METHODS Noncycloplegic refraction was determined by autorefractometer and validated by qualified optometrists. Myopia, defined on the basis of right eye spherical equivalence, was classified as mild (-0.75 to -2.99 diopters [D]), moderate (-3.0 to -5.99 D), or severe (-6.0 D or worse). The photoperiod was recorded from astronomical tables and classified into 4 categories. Using multivariate logistic regression models, we calculated odds ratios (ORs) for several risk factors of myopia including season of birth. MAIN OUTCOME MEASURE The OR for photoperiod categories as risk factors for myopia. RESULTS Overall prevalences of mild, moderate, and severe myopia were 18.8%, 8.7%, and 2.4%, respectively. There were seasonal variations in moderate and severe myopia according to birth month, with prevalence highest for June/July births and lowest for December/January. On multivariate logistic regression, the ORs of photoperiod categories for moderate and severe myopia were highly significant and demonstrated a dose-response pattern. Odds ratios for severe myopia were highest for the shortest versus the longest photoperiods (1.24; 95% confidence interval, 1.15-1.33; P<0.001). Mild myopia was not associated with season of birth or perinatal light exposure. Other risk factors were gender (1.14 for female), education level (1.32 for age above 12), and father's origin (1.31 for Eastern vs. Israeli origin). CONCLUSION Myopia in this population is associated with birth during summer months. The exact associating mechanism is not known but might be related to exposure to natural light during the early perinatal period.
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Affiliation(s)
- Yossi Mandel
- Israel Defense Force Medical Corps, Ramat-Gan, Israel.
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21
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Chotai J, Murphy DL, Constantino JN. Cerebrospinal fluid monoamine metabolite levels in human newborn infants born in winter differ from those born in summer. Psychiatry Res 2006; 145:189-97. [PMID: 17074397 DOI: 10.1016/j.psychres.2005.11.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Revised: 09/25/2005] [Accepted: 11/16/2005] [Indexed: 01/06/2023]
Abstract
An earlier study has shown significant differences in the CSF monoamine metabolite levels in adults born during different seasons of the year. We study here the relationship between season of birth and CSF monoamine metabolite levels in 283 newborn febrile infants without neurological abnormalities, with an age distribution ranging from birth to about 3 months, adjusting for the confounding variables age and time at lumbar puncture, weight at birth, estimated gestational age at birth, gender, race, and medicaid status. Each of the three metabolite levels as well as their ratios HVA/5-HIAA and 5-HIAA/MHPG showed significant month-of-birth variations, but not the ratio HVA/MHPG. For HVA and MHPG levels, the maximum was obtained around the winter birth months November-December, whereas for 5-HIAA level, the maximum was obtained around the summer birth months June-July. The correlations between HVA and 5-HIAA were, in general, significantly positive within the different birth seasons and races. Among summer-born Caucasian infants, MHPG was significantly positively correlated with HVA and with 5-HIAA, whereas among winter-born Black infants, MHPG was significantly positively correlated with HVA. Season of birth is an unspecific environmental factor that may be proxy for several possible seasonally varying environmental circumstances such as the length of photoperiod, temperature, infections, nutrition, stress and lifestyle. Studies relating season of birth to monoaminergic turnover at different stages of life may yield important clues about the gestational and perinatal origins of neurodevelopment.
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Affiliation(s)
- Jayanti Chotai
- Division of Psychiatry, Department of Clinical Sciences, University of Umeå, SE-901 85 Umeå, Sweden.
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22
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The relationship between date of birth and individual differences in personality and general intelligence: A large-scale study. PERSONALITY AND INDIVIDUAL DIFFERENCES 2006. [DOI: 10.1016/j.paid.2005.11.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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23
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24
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Joinson C, Nettle D. Season of birth variation in sensation seeking in an adult population. PERSONALITY AND INDIVIDUAL DIFFERENCES 2005. [DOI: 10.1016/j.paid.2004.06.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Seeger G, Schloss P, Schmidt MH, Rüter-Jungfleisch A, Henn FA. Gene-environment interaction in hyperkinetic conduct disorder (HD + CD) as indicated by season of birth variations in dopamine receptor (DRD4) gene polymorphism. Neurosci Lett 2004; 366:282-6. [PMID: 15288435 DOI: 10.1016/j.neulet.2004.05.049] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2004] [Revised: 05/15/2004] [Accepted: 05/19/2004] [Indexed: 11/26/2022]
Abstract
Recently, an interaction between season of birth and the expression of candidate genes has been suggested. Season of birth variations in tryptophan hydroxylase (TPH), the serotonin transporter (5-HTTLPR) and the dopamine D4 receptor (DRD4) gene polymorphisms are different for affective disorders and schizophrenia. The DRD4 gene has been postulated as a candidate gene for attention-deficit-hyperactivity disorder (ADHD), equivalent to hyperkinetic disorder (HD). The seven-repeat long variant of this gene (DRD4*7) in comparison to the short repeat variants of the DRD4 gene polymorphism, has been found to be associated with ADHD. A seasonal pattern of birth has also been proposed for different subtypes of ADHD. Therefore, in a subgroup of children with HD and conduct disorder (CD) and in healthy controls, we investigated a possible association between the DRD4*7 allele and HD + CD in association with the season of birth. Supporting this hypothesis, we found an interaction between the seasons of birth and the expression of the DRD4 candidate gene in children with HD + CD as well as in controls, which differ significantly from each other. Depending on the season of birth, children carrying the DRD4*7R allele showed different relative risks for developing HD + CD.
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Affiliation(s)
- Gert Seeger
- Department of Child and Adolescent Psychiatry, Central Institute of Mental Health Mannheim, P.O. Box 122120, D-68072 Mannheim, Germany.
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26
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Tochigi M, Marumo K, Hibino H, Otowa T, Kato C, Marui T, Araki T, Otani T, Umekage T, Kato N, Sasaki T. Season of birth effect on personality in a general population. Neurosci Lett 2004; 365:120-3. [PMID: 15245791 DOI: 10.1016/j.neulet.2004.04.064] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Revised: 04/23/2004] [Accepted: 04/27/2004] [Indexed: 10/26/2022]
Abstract
Seasonality of births in schizophrenia and other mental disorders has been consistently observed. This may be through effects of unknown environmental factors that seasonally fluctuate on the brain development. The effects may affect cognitive function of the brain and behavioral characteristics that might be correlated with the development of personality not only in patients with mental disorders but also in healthy subjects. We, therefore, investigated the effects of season of birth on personality traits in healthy Japanese adults (n = 397). Personality traits were evaluated using the NEO Personality Inventory-Revised (NEO PI-R). A trend for lower Agreeableness in subjects born during winter (December to February) than other subjects was observed (P = 0.036, after correction for the multiple testing, multiple regression analysis adjusting for age and sex). Other major factors of the NEO PI-R, including Neuroticism, Extraversion, Openness and Conscientiousness, were not affected by season of birth. Further studies may be recommended to confirm the results, considering the relatively limited sample size. Evaluation of cognitive functions and behaviors using other measures including event-related potentials and functional MRI may also help the interpretation of the present result.
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Affiliation(s)
- Mamoru Tochigi
- Department of Neuropsychiatry, Graduate School of Medicine, University of Tokyo, Japan
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Abstract
For centuries, scientists are intrigued by the differences in personality between individuals. As early as in the ancient Greek civilization, people tried to formulate theories to systematize this diversity. With the increased interest in behavior genetics, personality was also considered a challenging phenotype. From the early start, studies suggested a heritable component in personality. After the successes of molecular genetic studies in unraveling the genetic basis of (mostly) monogenic diseases, the focus shifted towards complex traits, including psychiatric disorders. It was observed in several studies that personality measures differed between patients with psychiatric disorders and healthy controls. Therefore, normal personality was considered a viable endophenotype in the search for genes involved in psychiatric disorders such as affective disorders, ADHD and substance dependence. Genes that were to be found in studies on personality could be candidate genes for particular psychiatric disorders. In the course of time, however the study of genes for personality turned out to be at least as hard as the search for genes involved in other complex disorders. In this review, past studies, present problems and future directions concerning the study of personality genetics are discussed.
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Affiliation(s)
- S Van Gestel
- Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB8), University of Antwerp (UIA), Antwerpen, Belgium
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28
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Chotai J, Lundberg M, Adolfsson R. Variations in personality traits among adolescents and adults according to their season of birth in the general population: further evidence. PERSONALITY AND INDIVIDUAL DIFFERENCES 2003. [DOI: 10.1016/s0191-8869(02)00306-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chotai J, Serretti A, Lattuada E, Lorenzi C, Lilli R. Gene-environment interaction in psychiatric disorders as indicated by season of birth variations in tryptophan hydroxylase (TPH), serotonin transporter (5-HTTLPR) and dopamine receptor (DRD4) gene polymorphisms. Psychiatry Res 2003; 119:99-111. [PMID: 12860364 DOI: 10.1016/s0165-1781(03)00112-4] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Genetic and environmental factors, as well as their interactions, are likely to be involved in psychiatric disorders. Considerable progress has been made in association and linkage studies with various candidate genes, at times with conflicting or ambiguous results. An environmental factor that has persistently shown associations with several psychiatric and neurological disorders is the season of birth. If it is the interaction of a specific gene allele with a specific season of birth that constitutes an increased (or decreased) risk for a disorder, then the individuals with this disorder are likely to have a season of birth variation in this gene allele. We investigated the variations in TPH, 5-HTTLPR and DRD4 gene polymorphisms according to seasonality of birth in 954 patients with unipolar affective disorder, bipolar affective disorder, and schizophrenia, respectively, and in 395 controls. We first analyzed season of birth variations in the gene alleles with one cycle or two cycles per year, and then compared specified birth seasons with each other. We found season of birth variations in these gene alleles that were different for different psychiatric disorders. Significant differences between cases and controls could be obtained when restricting the analysis within certain birth seasons but not within others. Our results thus suggest an interaction between the seasons of birth and the expression of the candidate genes, and that season of birth is a confounding variable when investigating the role of the candidate genes in susceptibility to psychiatric disorders.
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Affiliation(s)
- Jayanti Chotai
- Division of Psychiatry, Department of Clinical Sciences, University of Umeå, 901 85, Umeå, Sweden.
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