The Temperamental Determinants of Stressors as Life Changes
A Genetic Analysis
Abstract
Behavioral genetic studies have demonstrated the heritability of many variables taken to be measures of environment and previously thought to be determined only by environment. It has been also shown that personal variables may determine the appearance of stressors understood as life changes (events). The hypothesis underlying this study predicted that the genetic factor does not contribute to the variance of subject-independent stressors, whereas in case of subject-dependent stressors the contribution of the genetic factor is essential. Further, it was hypothesized that temperamental traits that moderate the intensity of experienced stressors account for a considerable portion of the genetic variance of subject-dependent stressors. The study was conducted on 245 pairs of MZ and 219 pairs of DZ twins aged from 19 to 66. Stressors were assessed with the Polish adaptation of theRahe's Recent Life Changes Questionnaire. Based on two preliminary studies, life events were divided into three following categories: subject-independent life events, negative subject-dependent life events, and challenges. Temperament traits were measured by means of the Formal Characteristics of Behavior-Temperament Inventory. The data, based on structural equation models and multivariate genetic analysis, allowed for the following conclusions: (1) The variance of independent stressors can be explained by environment only, whereas the additive genetic model best fits the subject-dependent stressors. (2) Heritability of negative, subject-dependent stressors is lower than in case of challenges. (3) Temperament variables, among them especially activity, explain only one type of stressors challenges. (4) Additional analysis of data confirm the role of activity as a moderator that increases the risk of environmental effects and evokes challenges.
References
1989). Does emotionality predict stress? Findings from the normative aging study. Journal of Personality and Social Psychology , 56, 618– 624.
(1994). Genetic influences on job satisfaction and work values. Personal and Individual Differences , 17, 21– 33.
(1996). Life events and personality in late adolescence: Genetic and environmental relations. Behavior Genetics , 26, 543– 554.
(1985). Stress and bodily illness. In A. Monat, & R.S. Lazarus (Eds.), Stress and coping: An anthology (pp. 40-54). New York: Columbia University Press.
(1984). Invited review: Life events and physical illness. Journal of Psychosomatic Research , 29, 113– 123.
(1988). The impact of daily stress on health and mood: Psychological and social resources as mediators. Journal of Personality and Social Psychology , 54, 486– 495.
(1991). A Zigosity Questionnaire for young twins: A research note. Behavior Genetics , 21, 257– 269.
(1989). Personality, life events, and subjective well-being: Toward a dynamic equilibrium model. Journal of Personality and Social Psychology , 57, 731– 739.
(1967). The social readjustment rating scale. Journal of Psychosomatic Research , 11, 213– 218.
(1979). Life changes: Do people really remember. Archives of General Psychiatry , 36, 379– 384.
(1979). Moderator variables in life stress research. In I.G. Sarason & C.D. Spielberger (Eds.), Stress and anxiety (Vol. 6, pp. 151-167). New York: Hemisphere.
(1981). Comparison of two models of stress measurement: Daily hassles and uplifts vs. major life events. Journal of Behavioral Medicine , 4, 1– 39.
(1986). Models for the join effect of genotype and environment on liability to psychiatric illness. American Journal of Psychiatry , 143, 279– 289.
(1986). A twin study of recent life events and difficulties. Archives of General Psychiatry , 50, 789– 796.
(1992). Social support, depressed mood, and adjustment to stress: A genetic epidemiologic investigation. Journal of Personality and Social Psychology , 62, 257– 272.
(1996). Coping with multiple stressors in the environment. In M. Zeidner & N.S. Endler (Eds.), Handbook of coping: Theory, research, applications (pp. 322-349). New York: Wiley.
(1986). Transmission of social attitudes. Proceedings of the National Academy of Sciences USA , 83, 4364– 4368.
(1992). Methodology for genetic studies of twins and families . Dordrecht: Kluwer.
(1996). Diagnoza zygotyczności bliźniąt na podstawie Kwestionariusza Fizycznego Podobieństwa Bliźniąt [Diagnosis of twin zigosity on the basis of the questionnaire of the twins physical resemblance]. Przegląd Psychologiczny , 39, 161– 175.
(1979). Causal relationship between clinical depression and life events. In J.E. Barret (Eds.), Stress and mental disorders (pp. 71-86). New York: Raven.
(1994). Genetics end experience: The interplay between nature and nurture . Thousand Oaks, CA: Sage.
(1991). The nature of nurture: Genetic influence on “environmental” measures. Behavioral and Brain Sciences , 14, 373– 427.
(1977). Genotype-environment interaction and correlation in analysis of human behavior. Psychological Bulletin , 84, 309– 322.
(1990). Genetic influence on life events: During the last half of the life span. Psychology and Aging , 5, 25– 30.
(1994). Nature and nurture: Genetic contribution to measures of the family environment. Developmental Psychology , 30, 32– 43.
(1975). Epidemiological studies of life change and illness. International Journal of Psychiatry in Medicine , 6, 133– 146.
(1987). Recent life changes, emotions and behaviors in coronary heart disease. In A. Baum, & J.E. Singer (Eds.), Handbook of psychology and health (Vol. 5, pp. 229-254). Hillsdale, NJ: Erlbaum.
(1993). Acute versus chronic post-traumatic stress disorder. Integrative Physiological and Behavioral Science , 28, 46– 56.
(1978). Assessing the impact of live changes: Development of the Life Experience Survey. Journal of Consulting and Clinical Psychology , 46, 932– 946.
(1997). Can personality explain genetic influences on life events?. Journal of Personality and Social Psychology , 72, 196– 206.
(1980a). Differential weights in life change research: Useful or irrelevant?. Psychosomatic Medicine , 42, 367– 370.
(1980b). The multidimensional assessment of stressful life events. Journal of Nervous and Mental Disease , 168, 535– 541.
(1999). Kwestionariusz Zmian Życiowych (KZŻ): Polska adaptacja “Recent Life Changes Questionnaire” (RLCQ) R.H. Rahe'a. [Polish adaptation of R.H. Rahe's Recent Life Changes Questionnaire]. Przegląd Psychologiczny , 42, 27– 49.
(1995). Temperament and stress: Temperament as a moderator of stressors, emotional states, coping, and costs. In C.D. Spielberger, & I.G. Sarason (Eds.), Stress and emotion: Anxiety, anger, and curiosity (Vol. 15, pp. 207-229). Washington, DC: Hemisphere.
(1996). The regulative theory of temperament: Current status. Personality and Individual Differences , 20, 131– 142.
(1998). Temperament: A psychological perspective . New York: Plenum.
(1993). The Formal Characteristics of Behavior—Temperament Inventory (FCB-TI): Theoretical assumptions and scale construction. European Journal of Personality , 7, 313– 336.
(1981). Life events, perceived control and illness: The role of uncertainty. Journal of Human Stress , 30– 35.
(1993). Individual and cultural differences in adaptation to environmental risks. American Psychologist , 48, 673– 680.
(1987). Stress conceptions in life event research: Toward a person centered perspective. European Journal of Personality , 1, 123– 140.
(1983). Weighted vs. unweighted life event scores: Is there a difference?. Journal of Human Stress , 30– 35.
(