International trends in the education of students with special educational needs

21.4 A Comprehensive Ecological Model

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  Families comprise systems which are, in turn, embedded in a series of other systems –schools, communities, social, health, justice, recreational, political, environmental…
  
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  Such systems should be ‘joined up’, which involves both horizontal and vertical integration. Horizontal integration requires linking systems at the same level to ensure consistency and compatibility of approach. Vertical integration requires linking more immediate, or proximal, systems with the more distal systems in which they are embedded.
  
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  The whole is greater than the sum of its parts, a principle that requires that systems within different levels work together cohesively and with common purpose.
  

The model draws upon general systems theory (von Bertalanffy, 1962) and Bronfenbrenner’s ecological model of child development (Bronfenbrenner, 1979).

Anderson et al. (1999) have presented a useful definition of systems as being organised wholes comprising component parts that interact in a distinct way and endure over time.

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  a social system can be studied as a network of unique, interlocking relationships with discernible structural and communication patterns;
  

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  all systems are subsystems of other, larger systems;
  

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  boundaries of varying degrees of permeability give a social system its identity and focus as a system, distinguishing it from other social systems with which it may interact;
  

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  there is an interdependency and mutual interaction between and among social systems;
  

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  a change in any one member of the social system affects the nature of the social system as a whole;
  

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  social systems vary in the extent to which they are purposive, goal-directed and in constant states of interchange with their environments;
  

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  change within or from without a social system that moves the system to an imbalance in structure will result in an attempt by the system to re-establish that balance;
  

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  systems may be open or closed, depending on the degree to which they engage in exchanges with their environment (both receiving inputs and delivering outputs);
  

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  systems reach a ‘steady state’, or equilibrium, with respect to their exchanges with the environment;
  

Bronfenbrenner’s ecological model. Bronfenbrenner’s ecological model is well known and has been very influential in conceptualising the influences on child development (Bronfenbrenner, 1979). As will be seen below, this model forms a special case of the general systems theory. In an adapted form, it will form the basis of the present chapter.

In essence, Bronfenbrenner argues that child development takes place through processes of progressively more complex interactions between an active child and the persons, objects, and symbols in its immediate environment over an extended period of time (Bronfenbrenner, 1998). In these processes, the child affects as well as being affected by the settings in which it spends time. In other words, ‘there is reciprocal causation between the individual and the environment.’ (McElroy et al., 1988, p.354)

Bronfenbrenner identifies four levels of settings, which are nested rather like Russian dolls: the microsystem (the family or classroom), the mesosystem (two microsystems in interaction), the exosystem (external environments that indirectly influence development, e.g., parental workplace), and the macrosystem (the larger socio-cultural context, such as the individual’s ethnicity, culture and belief systems). Figure 21.1 presents his original ecological model of human development, but note it does not directly portray the mesosystem. In his later writings he added a fifth system, which he called the chromosystem, which referred to the evolution of the external systems over time. Note, too, that in his later writings, Bronfenbrenner (1988) acknowledged that he had neglected to place the individual child at the centre of its own ecological world; the figure below takes this into account.

In keeping with the joined-up philosophy adopted in this review, a more appropriate portrayal of the ecological model would be in the form of a spiral (Figure 21.2). This has the advantage of removing the barriers between each level of the system as portrayed in Figure 21.1, making for more fluid connections among the various levels of the system.