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Medical Approaches to Normality


Medical approaches to normality stress the idea of uniformity of physical and psychological functioning across individuals.

Limitations and disability

How did you define ‘normal’ eyesight? (see Definitions of Normality) The ability to see clearly without eye glasses? It is unlikely that you wrote down short- or long-sightedness as an example of ‘normal’ eyesight, even though they are very common. However, they are not seen as ‘normal’ because having to wear glasses is perceived as a limitation or even a form of disability. This relates to one of several so-called ‘medical models’ of normality, which centre on the idea of uniformity of physical and psychological functioning across individuals.

These models are often reductionist, proposing that disease or physical disorder of some kind can explain ‘abnormality’, although such explanations frequently acknowledge social and external factors that may trigger the physical ‘cause’ of a problem. Psychological conditions like depression can be viewed using medical approaches as the result of ‘abnormal’ functioning of the brain systems that govern mood and arousal. As a result, medical models often provide the rationale for many drug treatments (e.g. anti-depressants) aimed at correcting the presumed biochemical imbalances to restore ‘normal’ functioning.

Problems with medical approaches to ‘normality’

Regardless of the above, these simple reductionist approaches have proved unsuccessful because:

  1. The identification of many ‘disorders’ can be difficult in practice, because they appear to fall on a continuum with ‘normal’ functioning, so any clear distinction between ‘normal’ and ‘abnormal’ is frequently difficult to draw.
  2. Biochemical (drug) treatments often go hand-in-hand with a medical approach. However, there is still considerable uncertainty about the precise nature and origins of any biochemical abnormalities associated even with well-studied conditions like depression or schizophrenia, for which various drug treatments are in routine use. For others such as eating disorders, even less is known about possible biochemical contributions, if any exist at all.
  3. It is evident that many of our most common diseases are actually systemic – they arise from a breakdown of many complex interacting systems, and medical approaches acknowledge this. They should not be thought of as simple or reductionist explanations for physical or psychological disorders. For example, both heart disease and cancer arise from the interaction of genetic predisposition with environmental and lifestyle factors that include both biological and sociocultural influences. There is no reason to suppose that psychological disorders are any simpler.

The sheer complexity of the many interacting systems involved in human development and functioning means that even in physical disorders, realistic medical approaches are rarely simple or reductionist. In the same way that good medical models reflect complex interactions between different factors, so too should our models of psychology.

Several approaches

There are a number of approaches to defining ‘normality’:


  • Systemic: Belonging to or affecting the system or body as a whole. For example cardiovascular disease, with origins involving many interacting subsystems, is usually seen as systemic, whereas tuberculosis, caused by a single infectious agent, is not.


[Information last accessed: 27 July 2017]

This article draws on ‘Understanding dyslexia’. An OpenLearn ( chunk reworked by permission of The Open University copyright © 2016 – made available under the terms of the Creative Commons Licence v4.0 As such, it is also made available under the same licence agreement.