Developmental Perspectives on Behavior

Part A

Bronfenbrenner’s bioecological model

Bronfenbrenner’s bioecological model is important in the study of human development over time, and the gene-environment interactions. Bronfenbrenner held the view that the surrounding environment had a profound and pervasive impact on an individual’s development. Bronfenbrenner’s bioecological model has four distinct dimensions that are an improvement from the earlier ecological systems theory. These dimensions include: process, person, context, and lastly time (Freudenberg, Klitzman, & Saegert, 2009). The process dimension involves the interaction between an organism and the environment, and the energy exchanges that occur between them. The person is the individual who shows distinct characteristics. The context in which events occur and time are also crucial in the model.

Bronfenbrenner’s bioecological model also highlights the importance of various levels of the environment which he referred to as systems namely microsystem, mesosystem, exosystem, macrosystem, and chronosystem. The microsystem represents the direct environment that individuals come into contact with on daily basis (In Cicchetti & In Cohen, 2006). This includes the family, school, friends, neighbors and others who are in close contact. The mesosystem refers to the interrelations that exist between two or more microsystems, for example, peer groups, homes and schools.

The exosystem refers to the interactions between microsystems for which the individuals are not part of but which has certain implications upon their lives (Munhall & Fitzsimons, 2001). For instance, the impact of work environment on parents may in one way or another affect children who are not directly linked to the work environment. The macrosystem represents the culture in which all other systems occur for instance the social class, economic climate, subcultures, and others. The chronosystem is the last level. In this level, changes such as biological changes that occur due to aging may lead to a change in emotional relationships in children

Part B

Impact of genetic and environmental factors on pro-social attitudes in individuals

Rushton (2004) examined the impact of genetic and environmental factors on pro-social attitudes in individuals. In order to get accurate results, twin studies were conducted. Only a few studies had earlier tried to examine the impact of genetic factors on pro-social attitudes in individuals. The study would thus help shed light in the area. A few studies conducted on the subject indicated that genes were partly responsible to particular behaviors in individuals such as acts of violence, self-report altruism, empathy, aggression, and nurturance. The studies also reveal that environmental factors have a profound impact on pro-social behaviors of individuals. By examining monozygotic and dizygotic twins, the study addresses the question on how genetic and environmental factors influence pro-social behaviors among individuals.

Name the dependent variables. How do the authors measure the behavior/attitude/preference under investigation?

The dependent variables in the study are genetic factors and the environmental factors that are thought to have an impact on pro-social attitudes. The behavior/attitude under investigation are measured by close observation of monozygotic and dizygotic twins. Monozygotic twins have similar genes while dizygotic twins share 50% of their genes. By examining pairs of monozygotic and dizygotic twins, the author was able to develop a fair estimate of the variance resulting from genetic factors. A standardized social responsibility questionnaire bearing 22 items was used to obtained information from the respondents over a period of time. The questions prompted participants to agree on a scale of 1 to 5, with both positively keyed and negatively keyed items. Participants completed the questionnaires at their own discretion and mailed them back to the researchers. Data from participants was then analyzed based on age, sex, and the nature of twins. Attitudes and behaviors were thus measured based on self-reporting of participants.

Specific factors that were important predictions of the behavior

The author outlines certain factors as predictors of behavior. There was significant correlation among items in the social responsibility questionnaire indicating the items were evaluating the same construct. The study found that twin correlations were significantly higher among the 174 monozygotic pairs of twins. The observed correlation coefficient for this group was (r = 0.45). Twin correlations among dizygotic twins was slightly lower with a correlation coefficient of 0.32. This was among the 148 dizygotic pairs of twins who completed the study. This indicates that there is a high correlation of behaviors/attitudes among monozygotic twins. The differences were however greater in men with a correlation coefficient of 0.50 and 0.21 (monozygotic & dizygotic respectively) than in women who recorded a correlation coefficient of o.44 and 0.34 (monozygotic & dizygotic respectively). The difference between monozygotic and dizygotic correlations indicated that women are 26% likely to inherit behaviors while men are 58% likely to inherit behaviors.

The results were further analyzed to establish the impacts of additive genetic effects, common environment, and non-shared or unique environment. Phenotypic variances for the three factors were analyzed. The results indicated that genetic effects contributed by 42%, common environment by up to 23%, and non-shared environment by 35%.

Where would these influential factors fit in Bronfenbrenner’s model?

The genetic effects, common environment, and non-shared environmental factors can be fit into Bronfenbrenner’s model. The microsystem is the environment that individuals come into contact with on a daily basis. For instance the family members, neighbors, school, and others who are in close contact. Among young individuals, the microsystem primarily consists of the immediate family. The microsystem becomes complex as children advance in age. Twins who share the same environment may thus be categorized in the microsystem. The genetic factors can also be classified under the microsystem. Factors in the non-shared environment can be categorized in the macrosystem. The macrosystem is the culture in which other systems can be found. The macrosystem comprises of the economic climate, culture, subculture, and the social class of an individual. The macrosystem may impact twins in different ways. For instance, the social class and culture in which the twins are brought up may lead to significant differences in their behavior (In Cicchetti & In Cohen, 2006).

How might this behavior be influenced by other levels of the model?

The second level of the model, the mesosystems may also influence behavior. This level represents interactions between two or more microsystems, for instance, different families, peer groups, and schools. According to Bronfenbrenner, a child’s development is based on the type of links that exist between the ecosystems. When the links are strong and positive, children develop positive relationships within the microsystems (In Cicchetti & In Cohen, 2006). For example, a strong link between school and parents can help instill positive behavior in learners.

The exosystem level refers to interactions between microsystems for which individuals are not part of but may have particular implications on their lives. An example of this is the work environment. The parents’ work environment may indirectly influence the behavior of an individual. If parents work in a stressful environment, they may transfer the stress to their children at home affecting their emotional relationships. This may affect the children’s behavior in the long-run. Other factors in the exosystem include social support systems, health care systems, and educational systems. The last level in the model is chronosystem. In this level, changes such as biological changes that occur due to aging may lead to a change in emotional relationships among individuals. Although twins may bear similar behaviors during childhood, these behaviors may change as a result of personal choices and context.

References

Freudenberg, N., Klitzman, S., & Saegert, S. (2009). Urban health and society: Interdisciplinary approaches to research and practice. San Francisco, CA: Jossey-Bass.

In Cicchetti, D., & In Cohen, D. J. (2006). Developmental Psychopathology: Volume One. Hoboken, NJ: John Wiley & Sons.

Munhall, P. L., & Fitzsimons, V. M. (2001). The emergence of family into the 21st century. Boston: Jones and Bartlett Publishers.

Rushton, J.P. (2004). Genetic and environmental contributions to pro-social attitudes: A twin study of social responsibility. Proceedings from the Royal Society of London, 271, 2583- 2585.