Genetic Basis of Behaviour

8 Key excerpts on "Genetic Basis of Behaviour"

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  eBook - ePub

  Theoretical Approaches in Psychology

  • Matt Jarvis(Author)
  • 2005(Publication Date)
  • Routledge

    (Publisher)

  8 Biological psychology 1: genetic influences on behaviour

  Key assumptions of the approach Behavioural genetics: the genetics of individual differences Evolutionary psychology: the genetics of human similarity Contemporary issue: does behavioural genetics pose a threat to other psychological approaches? Contributions and limitations of genetically based approaches Summary

  Key assumptions of the approach

  Have you ever wondered why a particular characteristic like high IQ or perhaps a bad temper seems to run in your family? Thinking about people more generally, have you ever considered why people prefer to go to the toilet alone, or why a young man going out with an older woman raises eyebrows whereas no one looks twice at an older man partnered with a young woman? Although there are many possible explanations for these patterns, there has recently been an upsurge of interest in biological explanations for these and many other psychological phenomena. Over the next two chapters we shall look at three major concepts from biology that have proved useful in explaining human psychology—genetics, evolution and neurophysiology.

  Genetics is the study of inheritance, and has been applied to psychology in looking at the extent to which psychological characteristics are affected by inheritance from parents. Evolution

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  AP® Psychology All Access Book + Online + Mobile

  • Nancy Fenton, Jessica Flitter(Authors)
  • 2015(Publication Date)
  • Research & Education Association

    (Publisher)

  Chapter 5 Biological Bases of Behavior

  Biological psychology can be traced to the beginnings of psychology because it has its roots in physiology. The field of biological psychology , also called neuroscience , focuses on how genes, the nervous system, and the endocrine system influence behaviors and mental processes. Technological advances have allowed biological psychologists to provide a more complete understanding of what occurs on a physiological level during a psychological experience such as thinking or memory.

  Heredity, Environment, and Evolution

  An important aspect of the study of psychology is the interplay among genetic, environmental, and evolutionary influences. Complex human traits, such as intelligence, aggression, altruism, and personality, are influenced by all of these factors. For instance, psychologists attempt to determine how an individual’s level of aggression is impacted by inheritance and exposure to violence, as well as why aggressive tendencies were naturally selected.

  Biologists and psychologists are both interested in the various influences of nature and nurture on human traits. Biologists study physical traits, such as height and eye color, or susceptibility to diseases, such as cancer. In contrast, psychologists are interested in behavioral traits and psychological illnesses. Behavioral traits include aggression, intelligence, personality, etc.; psychological illnesses include anxiety, schizophrenia, depression, etc. The scientific discipline of behavioral genetics attempts to integrate the influences of heredity, environment, and evolution in terms of their effect on human behavior.

  Heredity

  Biological psychologists are interested in the study of heredity, or how the traits of parents are transmitted biologically to offspring. The nucleus of each human cell contains forty-six chromosomes , twenty-three donated by each parent. Chromosomes that determine gender are known as the X and Y chromosomes . One X chromosome is donated by the mother, and either an X or Y chromosome is donated by the father. An XX individual is female; an XY person is male. Each chromosome contains genes , which are made up of a chainlike molecule called deoxyribonucleic acid (DNA) . Each individual gene can be either dominant or recessive. A dominant gene takes precedence over a recessive gene for that particular trait. For the gene that determines eye color in humans, brown is the dominant gene and blue is the recessive gene. If either parent donates a dominant gene for eye color, the child will have brown eyes. If both parents donate recessive genes for eye color, the child will have blue eyes. A Punnett square can be used to predict the outcome of various traits. The genotype is the genetic makeup for a trait in an individual, which may or may not be expressed, while the observable characteristics of genes are referred to as the phenotype

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  Growing Points in Developmental Science

  An Introduction

  • Willard W. Hartup, Rainer K. Silbereisen(Authors)
  • 2005(Publication Date)
  • Psychology Press

    (Publisher)

  3 Behavioural genetics in the 21st century

  Robert Plomin

  Institute of Psychiatry, London, UK

  The controversy that swirled around behavioural genetics research during the 1970s has largely faded. During the 1980s and especially the 1990s, the behavioural sciences became much more accepting of genetic influence, as can be seen in the growing number of behavioural genetic articles in mainstream behavioural journals and in research grants. In my view, this is one of the most dramatic shifts in the modern history of the behavioural sciences. The purpose of this chapter is to consider new directions for research in the field of behavioural genetics.

  Behavioural genetics is the genetic study of behaviour, which includes quantitative genetics (twin and adoption studies) as well as molecular genetics (DNA studies) of human and animal behaviour broadly defined to include responses of the organism, from responses measured in the brain, such as functional neuroimaging, to self-report questionnaires. Although animal models permit more powerful methods of analysis because both the genome and the environment can be manipulated, the present chapter focuses on genetic research that can be conducted in the human species.

  No crystal ball is needed to predict that the momentum of recent developments will carry the field of behavioural genetics well into the new millennium. This momentum is propelled by new findings, methods, and projects in quantitative genetics and especially in molecular genetics. The momentum will grow stronger as genetics continues to flow into the mainstream of behavioural research. Instead of only a hundred or so behavioural geneticists working on personality and cognition (and again as many in psychopathology), more behavioural scientists will incorporate these techniques in their research. This “giving away” of behavioural genetics is already happening, with some well-known behavioural scientists leading the way (Plomin, 1993). This is an important trend because the best behavioural genetic research will be done by behavioural scientists who are not primarily geneticists and who use these methods to address theory-driven issues in their speciality fields. For this reason, a major motivation for writing this piece is to entice other behavioural scientists, and especially the next generation of behavioural scientists, to incorporate genetics in their research.

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  Principles Of Comparative Psychology

  • Nicky Hayes(Author)
  • 2014(Publication Date)
  • Psychology Press

    (Publisher)

  2 The basis of behaviour

  I

  n this chapter, we will be looking at the some of the mechanisms that underlie behaviour. When we are looking at a particular behaviour shown by an animal, one of the first things we tend to ask is: where does this behaviour come from? How did it come to be like it is?

  Comparative psychology has addressed this question from a number of levels, ranging from that of the neurological factors controlling behaviour, to the influence of contexts and timing on whether the behaviour shows itself or not. Effectively, the origins of behaviour can be seen as coming from one of two sources, genetic transmission or learning—although it is important to remember that any behaviour that we actually observe an animal doing, at least in its natural environment, will almost always have been influenced by both factors. We will look first at how these different mechanisms work, before going on to see how they may combine together to influence what animals actually do.

  Genetic transmission

  Genetic transmission is the way that characteristics are passed on from one generation to another through inheritance. The way that it takes place is through a special kind of cell division. Each cell nucleus in the body contains long double strands of deoxyribonucleic acid, or DNA for short. These strands contain coded sequences of amino acids which form what we know as genes—units of heredity. Each gene has a pair, called an allele , on the opposite strand of DNA, and cross-links between the strands ensure that the two stay in place with respect to one another.

  A gene, when it becomes active, effectively issues an instruction to a particular cell that, at a given time, it should synthesise a particular protein. But the combined effects of millions of genes working together in a complex and ordered fashion, are such that this process can result in the development and growth of a whole living creature. The “genetic blueprint” in the coded strands of DNA contains the codes that will produce the individual, given the right environmental conditions and resources.

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  Genetic Diversity and Human Behavior

  • J.N. Spuhler(Author)
  • 2017(Publication Date)
  • Routledge

    (Publisher)

  Behavior Genetics as the Study of Mechanism-Specific Behavior Delbert D. Thiessen and David A. Rodgers

  BEHAVIOR GENETICS is rapidly gaining acceptance as a substantive discipline within psychology. In the 1965 Annual Review of Psychology, Bell observed that “the burgeoning and productive field of behavior genetics in animals hardly seems in need of advocacy” (p. 3). In the 1966 Annual Review, McClearn and Meredith called the growth “explosive.” The direction of growth of this vigorous infant is already a matter of concern and controversy. For example, Caspari (1963) comments that the most direct approach to behavior by genetic means will “not turn out to be very promising.” He is referring to the establishment of differences in behavioral characteristics between strains or sublines and subsequent analysis of their genetic behavior in crosses, a common paradigm of behavior genetics studies.

  Commenting on the same trend, Ginsburg (1958) observed that such an approach “brings us to the threshold of a locked door.” Notwithstanding these misgivings, the main emphasis of the behavior genetics movement still seems to be, as Meissner has recently expressed, “on the determination of the genotypes corresponding to the psychological phenotypes. The overriding concern [is] to identify the genetic factors to which the observed variance in psychological abilities and performance could be ascribed” (1965). These goals may be partly a reaction against past tendencies toward overgeneralizations that are based on genetically heterogeneous colonies of laboratory rats and that assume biological differences of behaving organisms are of little consequence. Commenting on such overgeneralization, Bitterman (1965) wrote, “It is difficult for the nonspecialist to appreciate quite how restricted has been the range of animals studied in experiments on animal learning because the restriction is so marked.”

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  Threats To Optimal Development

  Integrating Biological, Psychological, and Social Risk Factors: the Minnesota Symposia on Child Psychology, Volume 27

  • Charles A. Nelson(Author)
  • 2013(Publication Date)
  • Routledge

    (Publisher)

  Gottesman and Goldsmith make the important distinction between distal and proximal determinants of behavior. The proximal determinant of an aggressive act is the context in which it occurs. Genetic factors, to the extent they are relevant, necessarily, exert a remote and probabilistic influence either by affecting the likelihood an individual is exposed to a provocative situation or be affecting the likelihood the individual will respond when provoked. The challenge to the current generation of behavioral geneticists is not so much in proving the existence of that indirect effect, but rather in demonstrating how knowledge of these distal influences might help developmentalists characterize the mechanisms that underlie behavior.

  Stent (1981), in surveying progress in developmental neurogenetics, contrasted two broad approaches for characterizing the mechanisms of genetic influence. These same two approaches are represented in the Gottesman and Goldsmith chapter and serve to define current research strategies in behavioral genetics. Under an ideological approach, the establishment of a genetic influence provides sufficient justification for initiating attempts at identifying the specific gene, or more likely genes, involved. The goal in this “bottom-up” approach is to map the gene-to-behavior pathway by first identifying the primary gene product and then tracing the influence of that product through intermediate physiological and neurochemical systems until one reaches the behavioral level. Gottesman and Goldsmith review recent advances in molecular genetics that have greatly increased the feasibility of this approach. In particular the identification of highly polymorphic, noncoding segments of DNA (Botstein, White, Skolnick, & Davis, 1980) has allowed human geneticists to map much of the human genome; more than 2,000 structural genes have now been mapped. We are rapidly approaching the day when identifying the gene(s) that underlie expression of any inherited condition will be a matter of establishing a rich library of genetic probes, obtaining the cooperation of a sample of large families who are informative with respect to the condition, and persistence. Nonetheless, one need only consider current failures to produce replicable genetic linkages for alcoholism (Gelernter, Goldman, & Risch, 1993), schizophrenia (Sherrington et al., 1988), manic-depressive illness (Egeland, Gerhard, Pauls, Sussex, & Kidd, 1987), and reading disability (Smith, Kimberling, Pennington, & Lubs, 1983), to realize that progress with the application of molecular genetic methods to human behavior is likely to be much slower than that witnessed with classical genetic disorders like cystic fibrosis and Huntington Disease.

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  The SAGE Handbook of Evolutionary Psychology

  Integration of Evolutionary Psychology with Other Disciplines

  • Todd K. Shackelford, Todd K. Shackelford(Authors)
  • 2020(Publication Date)
  • SAGE Publications Ltd

    (Publisher)

  Behavioral genetic research is largely interested in determining the degree to which genetic variation accounts for phenotypic variation and the degree to which environmental variation accounts for phenotypic variation. For the most part, behavioral geneticists study the interplay of genetic and environmental influences on individual differences in phenotypes, whereas evolutionary psychologists tend to focus on the ultimate, universally adapted causes of behavior (Ferguson, 2010). While these directions may seem divergent, the two fields of study are more compatible than they initially appear. In the following paragraphs, we will present a brief overview of behavioral genetics, which should provide the necessary groundwork for understanding the key aims, methods, and findings of behavioral genetic research.

  Behavioral genetic designs allow for the estimation of genetic and environmental contributors to phenotypic variance. To do so, most behavioral genetic studies have analyzed data from family members (e.g., parent–offspring, siblings, cousins, etc.). The key reason for analyzing family members is that by comparing the degree of genetic relatedness among family members and then contrasting that genetic resemblance with phenotypic resemblance, it is possible to estimate the effect of genetic and environmental influences on a phenotype. These types of genetically sensitive research designs stand in stark contrast to the SSSM, which typically only employs samples that consist of one person per family. The result is that the SSSM is unable to estimate genetic and

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  Handbook of Developmental Science, Behavior, and Genetics

  • Kathryn E. Hood, Carolyn Tucker Halpern, Gary Greenberg, Richard M. Lerner(Authors)
  • 2011(Publication Date)
  • Wiley-Blackwell

    (Publisher)

  Behavior Genetics, and the founding of the Behavior Genetics Association with Ukranian-American geneticist Theodosius Dobzhansky as its first president.

  In later years, advances in molecular biology facilitated the investigation of the role that genes played in the development of a phenotype at the molecular level. When the focus was on humans, however, ethical considerations largely confined behavioral geneticists to traditional quantitative genetic methods. Thus, classic twin and adoption studies were employed to evaluate the relative contributions of different sources of variation, along with gene-hunting studies, which track the distribution ofgenetic markers in families (linkage studies) or populations (association studies) in an attempt to seek out candidate genes associated with behavioral traits (Kendler, 2005).

  While traditional, quantitative behavioral genetics is a clearly defined field, both intellectually and institutionally, developmental behavioral genetics is less a field than an aspiration. Understanding the role of genes in behavioral development is clearly amongst the most important desiderata for contemporary life and social science, but it is far from clear what kinds of studies will yield this understanding, whether this issue defines a single field with a distinctive set of methods, and how such a field would relate to traditional behavioral genetics. The most straightforward vision of a developmental behavioral genetics involves the application of the traditional behavioral genetic methods to developmental data, that is, to repeated observations of the same phenotype at different stages of development – the study of “distributions of individuals developing across time” as Sandra Scarr has characterized the field (Scarr, 1995, p. 158; see also Plomin, 1983). Scarr, following in the Fisherian tradition of focusing on the relative contributions of various sources of variation, argued that developmental behavioral genetics should seek the causes of phenotypic variation, rather than the causes of phenotypes, and ask how much phenotypes depend on certain causes, rather than how

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