Laboratory experimentation

Psychology has adapted the principles of positivist research to develop a wide range of laboratory-based approaches to research. Typically, such research seeks to test a hypothesis in controlled circumstances. In other words, all independent variables (causes) are controlled apart from a test variable to investigate the effect on a dependent variable (effect).

In the simplest model, two 'treatments' (independent variables) are compared: for example, subjects are exposed to two different sound stimuli such as tones of different frequencies, to compare the effects on heart rate (dependent variable). The heart rates observed are then analysed using inferential statistics such as the 't-test' which can evaluate whether the differences are due to chance or to the two treatments.

Psychologists have explored many aspects of human and animal behaviour using this kind of approach. Advantages are that the effects of confounding variables are controlled, including the influence of observation on behaviour; disadvantages are associated with the lack of relationship to the 'real world'.