Introduction to developmental psychology

Developmental psychology is the scientific study of progressive psychological changes that occur in human beings as they age. Originally concerned with infants and children, and later other periods of great change such as adolescence and aging, it now encompasses the entire life span. This field examines change across a broad range of topics including: motor skills and other psycho-physiological processes, problem solving abilities, conceptual understanding, acquisition of language, moral understanding, and identity formation.

Some examples of questions addressed by developmental psychologists include the following:
 * Are children qualitatively different from adults or do they simply lack the experience that adults draw upon?
 * Does development occur through the gradual accumulation of knowledge or through shifts from one stage of thinking to another?
 * Are children born with innate knowledge or do they figure things out through experience?
 * Is development driven by the social context or by something inside each child?

Developmental psychology informs several applied fields, including: educational/school psychology, child psychopathology and developmental forensics. Developmental psychology complements several other basic research fields in psychology including social psychology, cognitive psychology, and comparative psychology.

Theory
Many theoretical perspectives attempt to explain development, among the most prominent are: Jean Piaget's Stage Theory, Lev Vygotsky's Social Contextualism (and its heir, the Development in Context or Human Ecology theory of Urie Bronfenbrenner), and especially the information processing framework employed by cognitive psychology.

Historical theories continue to provide a basis for additional research, among them are Erik Erikson's eight stages of psychosocial development and John B. Watson's and B. F. Skinner's Behaviorism. Many other theories are prominent for their contributions to particular aspects of development. For example, Attachment theory describes kinds of interpersonal relationships and Lawrence Kohlberg describes stages in moral reasoning.

Role of experience
A significant question in developmental psychology is the relation between innateness and environmental influence in regard to any particular aspect of development. This is often referred to as "nature versus nurture" or nativism versus empiricism. A nativist account of development would argue that the processes in question are innate, that is, they are specified by the organism's genes. An empiricist perspective would argue that those processes are aquired in interaction with the environment. Today developmental psychologists rarely take such extreme positions with regard to most aspects of development; rather they investigate (among many other things) the relationship between innate and environmental influences.

One area where this innateness debate has been prominently portrayed is in research on language acquisition. A major question in this area is whether or not certain properties of human language are specified genetically or can be acquired through learning. The nativist position argues that the input from language is too impoverished for infants and children to acquire the structure of language. Linguist Noam Chomsky asserts that, evidenced by the lack of sufficient information in the language input, there is a universal grammar that applies to all human languages and is pre-specified. This has led to the idea that there is a special cognitive module suited for learning language, often called the language acquisition device.

The empiricist position on the issue of language acqusition suggests that the language input does provide the necessary information required for learning the structure of language and that infants acquire language through a process of statistical learning. From this perspective, language can be acquired via general learning methods that also apply to other aspects of development, such as perceptual learning. There is a great deal of evidence for components of both the nativist and empiricist position, and this is a hotly debated research topic in developmental psychology.

On the other hand, Chomsky's critique of a specific nativist position on this issue, radical behaviorist B. F. Skinner's Verbal Behavior (1957), is widely considered among developmental psychologists to have sparked the decline in influence of behaviorism and signaled the beginning of the cognitive revolution in psychology.

Mechanisms of development
Developmental psychology is concerned not only with describing the characteristics of psychological change over time, but also seeks to explain the principles and internal workings underlying these changes. Understanding these factors is aided by the use of models. Developmental models are often computational, but they do not necessarily need to be. A model must simply account for the means by which a process takes place. This is sometimes done in reference to changes in the brain that may correspond to changes in behavior over the course of the development. Computational accounts of development often use either symbolic, connectionist (neural network), or dynamical systems models to explain the mechanisms of development.

History of Developmental Psychology
The modern form of developmental psychology has its roots in the rich psychological tradition represented by Heraclitus, Aristotle and Descartes. In the late nineteenth century, psychologists familiar with the evolutionary theory of Darwin began seeking an evolutionary description of psychological development; prominent here was G. Stanley Hall, who attempted to correlate ages of childhood with previous ages of mankind. A more scientific approach was initiated by James Mark Baldwin, who wrote essays on topics that included Imitation: A Chapter in the Natural History of Consciousness and Mental Development in the Child and the Race: Methods and Processes. By the early to mid-twentieth century, the work of Vygotsky and Piaget, mentioned above, had established a strong empirical tradition in the field.

Developmental psychology made an early appearance in a more literary form, however. William Shakespeare had his melancholy character Jacques (in As You Like It) articulate the seven ages of man: these included three stages of childhood and four of adulthood. In the mid-eighteenth century Jean Jacques Rousseau described three stages of childhood: infans (infancy), puer (childhood) and adolescence in Emile: Or, On Education. Rousseau's ideas were taken up strongly by educators at the time. In the twentieth century, Rudolf Steiner also articulated ages of psychological development, three of which lay in childhood, beginning with his essay The Education of the Child (1911); his descriptions have also been taken up by educators (in the Waldorf Schools) and psychologists (in biographical therapy; see the works of Bernard Lievegoed).

Aspects of development
Developmental psychology is concerned with many different components of human psychology and how they change over time. These different aspects of development complement many other areas of psychology, including cognitive psychology and social psychology.

Cognitive development
Main article: Cognitive psychology.

Cognitive development is primarily concerned with the ways in which infants and children acquire cognitive abilities. Major topics in cognitive development are the study of language acquisiton and the development of perceptual and motor skills. Piaget was one of the influential early psychologists to study the development of cognitive abilities. His theory suggest that development proceeds through a set of stages from infancy to adulthood. Other accounts, however, have suggested that development does not progress through stages that are as clearly defined as those of Piaget's. Rather, from this viewpoint, developmental processes proceed more continuously, but often give rise to apparent stages of change in mental structures as Piaget described.

Social development
Main article: Social psychology.

Social psychology is the study of the nature and causes of human social behavior, with an emphasis on how people think towards each other and how they relate to each other. As the mind is the axis around which social behavior pivots, social psychologists tend to study the relationship between mind(s) and social behaviors. In early-modern social science theory, John Stuart Mill, Comte, and others, laid the foundation for social psychology by asserting that human social cognition and behavior could and should be studied scientifically like any other natural science.

Research methods
Developmental psychology employs many of the research methods used in other areas of psychology. However, infants and children cannot always be tested in the same ways as adults, so different methods are often used to study development.

Infant research methods. When studying infants, the habituation methodology is an example of a method often used to assess their performance. This method allows researchers to obtain information about what types of stimuli an infant is able to discriminate. In this paradigm, infants are habituated to a particular stimulus and are then tested using different stimuli to evaluate discrimination. The critical measure in habituation is the infants' level of interest. Typically, infants prefer stimuli that are novel relative to those they have encountered previously. Several methods are used to measure infants' preference. These include the high-amplitude sucking procedure, in which infants suck on a pacifier more or less depending on their level of interest, the conditioned foot-kick procedure, in which infants move their legs to indicate preference, and the head-turn preference procedure, in which infants level of interest is measured by the amount of time spent looking in a particular direction. A key feature of all these methods is that, in each situation, the infant controls the stimuli being presented. This gives researchers a means of measuring discrimination. If an infant is able to discriminate between the habituated stimulus and a novel stimulus, they will show a preference for the novel stimulus. If, however, the infant cannot discriminate between the two stimuli, they will not show a preference for one over the other.

Child research methods. When studying older children, especially adolescents, adult measurements of behavior can often be used, but they may need to be simplified to allow children to perform certain tasks.

Related pages

 * Annotated Bibliography: a list of prominent works in developmental psychology

Theory
Many theoretical perspectives attempt to explain development, among the most prominent are: Jean Piaget's Stage Theory, Lev Vygotsky's Social Contextualism (and its heir, the Development in Context or Human Ecology theory of Urie Bronfenbrenner), and especially the information processing framework employed by cognitive psychology.

Historical theories continue to provide a basis for additional research, among them are Erik Erikson's eight stages of psychosocial development and John B. Watson's and B. F. Skinner's Behaviorism. Many other theories are prominent for their contributions to particular aspects of development. For example, Attachment theory describes kinds of interpersonal relationships and Lawrence Kohlberg describes stages in moral reasoning.

Role of experience
A significant question in developmental psychology is the relation between innateness and environmental influence in regard to any particular aspect of development. This is often referred to as "nature versus nurture" or nativism versus empiricism. A nativist account of development would argue that the processes in question are innate, that is, they are specified by the organism's genes. An empiricist perspective would argue that those processes are aquired in interaction with the environment. Today developmental psychologists rarely take such extreme positions with regard to most aspects of development; rather they investigate (among many other things) the relationship between innate and environmental influences.

One area where this innateness debate has been prominently portrayed is in research on language acquisition. A major question in this area is whether or not certain properties of human language are specified genetically or can be acquired through learning. The nativist position argues that the input from language is too impoverished for infants and children to acquire the structure of language. Linguist Noam Chomsky asserts that, evidenced by the lack of sufficient information in the language input, there is a universal grammar that applies to all human languages and is pre-specified. This has led to the idea that there is a special cognitive module suited for learning language, often called the language acquisition device.

The empiricist position on the issue of language acqusition suggests that the language input does provide the necessary information required for learning the structure of language and that infants acquire language through a process of statistical learning. From this perspective, language can be acquired via general learning methods that also apply to other aspects of development, such as perceptual learning. There is a great deal of evidence for components of both the nativist and empiricist position, and this is a hotly debated research topic in developmental psychology.

On the other hand, Chomsky's critique of a specific nativist position on this issue, radical behaviorist B. F. Skinner's Verbal Behavior (1957), is widely considered among developmental psychologists to have sparked the decline in influence of behaviorism and signaled the beginning of the cognitive revolution in psychology.

Mechanisms of development
Developmental psychology is concerned not only with describing the characteristics of psychological change over time, but also seeks to explain the principles and internal workings underlying these changes. Understanding these factors is aided by the use of models. Developmental models are often computational, but they do not necessarily need to be. A model must simply account for the means by which a process takes place. This is sometimes done in reference to changes in the brain that may correspond to changes in behavior over the course of the development. Computational accounts of development often use either symbolic, connectionist (neural network), or dynamical systems models to explain the mechanisms of development.

History of Developmental Psychology
The modern form of developmental psychology has its roots in the rich psychological tradition represented by Heraclitus, Aristotle and Descartes. In the late nineteenth century, psychologists familiar with the evolutionary theory of Darwin began seeking an evolutionary description of psychological development; prominent here was G. Stanley Hall, who attempted to correlate ages of childhood with previous ages of mankind. A more scientific approach was initiated by James Mark Baldwin, who wrote essays on topics that included Imitation: A Chapter in the Natural History of Consciousness and Mental Development in the Child and the Race: Methods and Processes. By the early to mid-twentieth century, the work of Vygotsky and Piaget, mentioned above, had established a strong empirical tradition in the field.

Developmental psychology made an early appearance in a more literary form, however. William Shakespeare had his melancholy character Jacques (in As You Like It) articulate the seven ages of man: these included three stages of childhood and four of adulthood. In the mid-eighteenth century Jean Jacques Rousseau described three stages of childhood: infans (infancy), puer (childhood) and adolescence in Emile: Or, On Education. Rousseau's ideas were taken up strongly by educators at the time. In the twentieth century, Rudolf Steiner also articulated ages of psychological development, three of which lay in childhood, beginning with his essay The Education of the Child (1911); his descriptions have also been taken up by educators (in the Waldorf Schools) and psychologists (in biographical therapy; see the works of Bernard Lievegoed).

Aspects of development
Developmental psychology is concerned with many different components of human psychology and how they change over time. These different aspects of development complement many other areas of psychology, including cognitive psychology and social psychology.

Cognitive development
Main article: Cognitive psychology.

Cognitive development is primarily concerned with the ways in which infants and children acquire cognitive abilities. Major topics in cognitive development are the study of language acquisiton and the development of perceptual and motor skills. Piaget was one of the influential early psychologists to study the development of cognitive abilities. His theory suggest that development proceeds through a set of stages from infancy to adulthood. Other accounts, however, have suggested that development does not progress through stages that are as clearly defined as those of Piaget's. Rather, from this viewpoint, developmental processes proceed more continuously, but often give rise to apparent stages of change in mental structures as Piaget described.

Social development
Main article: Social psychology.

Social psychology is the study of the nature and causes of human social behavior, with an emphasis on how people think towards each other and how they relate to each other. As the mind is the axis around which social behavior pivots, social psychologists tend to study the relationship between mind(s) and social behaviors. In early-modern social science theory, John Stuart Mill, Comte, and others, laid the foundation for social psychology by asserting that human social cognition and behavior could and should be studied scientifically like any other natural science.

Research methods
Developmental psychology employs many of the research methods used in other areas of psychology. However, infants and children cannot always be tested in the same ways as adults, so different methods are often used to study development.

Infant research methods. When studying infants, the habituation methodology is an example of a method often used to assess their performance. This method allows researchers to obtain information about what types of stimuli an infant is able to discriminate. In this paradigm, infants are habituated to a particular stimulus and are then tested using different stimuli to evaluate discrimination. The critical measure in habituation is the infants' level of interest. Typically, infants prefer stimuli that are novel relative to those they have encountered previously. Several methods are used to measure infants' preference. These include the high-amplitude sucking procedure, in which infants suck on a pacifier more or less depending on their level of interest, the conditioned foot-kick procedure, in which infants move their legs to indicate preference, and the head-turn preference procedure, in which infants level of interest is measured by the amount of time spent looking in a particular direction. A key feature of all these methods is that, in each situation, the infant controls the stimuli being presented. This gives researchers a means of measuring discrimination. If an infant is able to discriminate between the habituated stimulus and a novel stimulus, they will show a preference for the novel stimulus. If, however, the infant cannot discriminate between the two stimuli, they will not show a preference for one over the other.

Child research methods. When studying older children, especially adolescents, adult measurements of behavior can often be used, but they may need to be simplified to allow children to perform certain tasks.

Related pages

 * Annotated Bibliography: a list of prominent works in developmental psychology

Theory
Many theoretical perspectives attempt to explain development, among the most prominent are: Jean Piaget's Stage Theory, Lev Vygotsky's Social Contextualism (and its heir, the Development in Context or Human Ecology theory of Urie Bronfenbrenner), and especially the information processing framework employed by cognitive psychology.

Historical theories continue to provide a basis for additional research, among them are Erik Erikson's eight stages of psychosocial development and John B. Watson's and B. F. Skinner's Behaviorism. Many other theories are prominent for their contributions to particular aspects of development. For example, Attachment theory describes kinds of interpersonal relationships and Lawrence Kohlberg describes stages in moral reasoning.

Role of experience
A significant question in developmental psychology is the relation between innateness and environmental influence in regard to any particular aspect of development. This is often referred to as "nature versus nurture" or nativism versus empiricism. A nativist account of development would argue that the processes in question are innate, that is, they are specified by the organism's genes. An empiricist perspective would argue that those processes are aquired in interaction with the environment. Today developmental psychologists rarely take such extreme positions with regard to most aspects of development; rather they investigate (among many other things) the relationship between innate and environmental influences.

One area where this innateness debate has been prominently portrayed is in research on language acquisition. A major question in this area is whether or not certain properties of human language are specified genetically or can be acquired through learning. The nativist position argues that the input from language is too impoverished for infants and children to acquire the structure of language. Linguist Noam Chomsky asserts that, evidenced by the lack of sufficient information in the language input, there is a universal grammar that applies to all human languages and is pre-specified. This has led to the idea that there is a special cognitive module suited for learning language, often called the language acquisition device.

The empiricist position on the issue of language acqusition suggests that the language input does provide the necessary information required for learning the structure of language and that infants acquire language through a process of statistical learning. From this perspective, language can be acquired via general learning methods that also apply to other aspects of development, such as perceptual learning. There is a great deal of evidence for components of both the nativist and empiricist position, and this is a hotly debated research topic in developmental psychology.

On the other hand, Chomsky's critique of a specific nativist position on this issue, radical behaviorist B. F. Skinner's Verbal Behavior (1957), is widely considered among developmental psychologists to have sparked the decline in influence of behaviorism and signaled the beginning of the cognitive revolution in psychology.

Mechanisms of development
Developmental psychology is concerned not only with describing the characteristics of psychological change over time, but also seeks to explain the principles and internal workings underlying these changes. Understanding these factors is aided by the use of models. Developmental models are often computational, but they do not necessarily need to be. A model must simply account for the means by which a process takes place. This is sometimes done in reference to changes in the brain that may correspond to changes in behavior over the course of the development. Computational accounts of development often use either symbolic, connectionist (neural network), or dynamical systems models to explain the mechanisms of development.

History of Developmental Psychology
The modern form of developmental psychology has its roots in the rich psychological tradition represented by Heraclitus, Aristotle and Descartes. In the late nineteenth century, psychologists familiar with the evolutionary theory of Darwin began seeking an evolutionary description of psychological development; prominent here was G. Stanley Hall, who attempted to correlate ages of childhood with previous ages of mankind. A more scientific approach was initiated by James Mark Baldwin, who wrote essays on topics that included Imitation: A Chapter in the Natural History of Consciousness and Mental Development in the Child and the Race: Methods and Processes. By the early to mid-twentieth century, the work of Vygotsky and Piaget, mentioned above, had established a strong empirical tradition in the field.

Developmental psychology made an early appearance in a more literary form, however. William Shakespeare had his melancholy character Jacques (in As You Like It) articulate the seven ages of man: these included three stages of childhood and four of adulthood. In the mid-eighteenth century Jean Jacques Rousseau described three stages of childhood: infans (infancy), puer (childhood) and adolescence in Emile: Or, On Education. Rousseau's ideas were taken up strongly by educators at the time. In the twentieth century, Rudolf Steiner also articulated ages of psychological development, three of which lay in childhood, beginning with his essay The Education of the Child (1911); his descriptions have also been taken up by educators (in the Waldorf Schools) and psychologists (in biographical therapy; see the works of Bernard Lievegoed).

Aspects of development
Developmental psychology is concerned with many different components of human psychology and how they change over time. These different aspects of development complement many other areas of psychology, including cognitive psychology and social psychology.

Cognitive development
Main article: Cognitive psychology.

Cognitive development is primarily concerned with the ways in which infants and children acquire cognitive abilities. Major topics in cognitive development are the study of language acquisiton and the development of perceptual and motor skills. Piaget was one of the influential early psychologists to study the development of cognitive abilities. His theory suggest that development proceeds through a set of stages from infancy to adulthood. Other accounts, however, have suggested that development does not progress through stages that are as clearly defined as those of Piaget's. Rather, from this viewpoint, developmental processes proceed more continuously, but often give rise to apparent stages of change in mental structures as Piaget described.

Social development
Main article: Social psychology.

Social psychology is the study of the nature and causes of human social behavior, with an emphasis on how people think towards each other and how they relate to each other. As the mind is the axis around which social behavior pivots, social psychologists tend to study the relationship between mind(s) and social behaviors. In early-modern social science theory, John Stuart Mill, Comte, and others, laid the foundation for social psychology by asserting that human social cognition and behavior could and should be studied scientifically like any other natural science.

Research methods
Developmental psychology employs many of the research methods used in other areas of psychology. However, infants and children cannot always be tested in the same ways as adults, so different methods are often used to study development.

Infant research methods. When studying infants, the habituation methodology is an example of a method often used to assess their performance. This method allows researchers to obtain information about what types of stimuli an infant is able to discriminate. In this paradigm, infants are habituated to a particular stimulus and are then tested using different stimuli to evaluate discrimination. The critical measure in habituation is the infants' level of interest. Typically, infants prefer stimuli that are novel relative to those they have encountered previously. Several methods are used to measure infants' preference. These include the high-amplitude sucking procedure, in which infants suck on a pacifier more or less depending on their level of interest, the conditioned foot-kick procedure, in which infants move their legs to indicate preference, and the head-turn preference procedure, in which infants level of interest is measured by the amount of time spent looking in a particular direction. A key feature of all these methods is that, in each situation, the infant controls the stimuli being presented. This gives researchers a means of measuring discrimination. If an infant is able to discriminate between the habituated stimulus and a novel stimulus, they will show a preference for the novel stimulus. If, however, the infant cannot discriminate between the two stimuli, they will not show a preference for one over the other.

Child research methods. When studying older children, especially adolescents, adult measurements of behavior can often be used, but they may need to be simplified to allow children to perform certain tasks.

Related pages

 * Annotated Bibliography: a list of prominent works in developmental psychology