The experimental approach in psychology has certain differences in comparison with the other sciences, which is probably caused by the peculiarity of the subject of investigation. In the most general view, psychology is considered as a science of "mind and behavior" and it studies the whole variety of aspects of human mental activity, including those that determine behavior. That is why, the lack of knowledge about the human mind is probably one of the reasons why the practice of experiment originated so late in psychology. Before they could start to bring actual results, the researches had to solve the following problems:
- To develop adequate research methods for studying the mind as a substance neither being exposed to a direct observation nor interacting with any object of such kind.
- To learn how to formulate the correct questions, which is crucial for experiments that are usually developed in order to answer some particular question, e.g. if some hypothesis is correct or not.
Starting with the first of these points, we may try to discover the common features of the human mental research methods. These features originate from the fact that it is still known so little about the subject. Of course, it is clear that the mental processing is carried out in the nervous system, which consists of the brain, spinal cord and the sympathetic nerves, but this kind of information has more value for neurophysiology then psychology. That's why one of the common features of the experimental psychology methods is the necessity to consider the incertitude of the mind organizational principles, still being able to answer the particular research question concerning some aspects of its activity.
In such a way, most methods represent the mind or the whole human being as an abstract "black box" and do not try to rely on any knowledge concerning its inner functional structure. This system also has certain inputs and outputs and the evaluation is carried out, providing a certain stimulation of inputs and comparing them to the output values, which the system gives in respond.
Ivan Tugoy, 2003
A thought experiment on a "black box" model
Let's carry out a thought experiment, featuring the valiant fortune hunter, who undertakes a safari into the heart of Africa to hunt a lion. Unfortunately the lion appears to have more lucky day and somehow takes an adventurer...
These studies also constitute the "black-box" research, with the taste and audio receptors as inputs and the saliva secretion as the output. Of course, the usual types of psychological assessment on humans are much simpler then Pavlov's experiments...
Types of psychological assessment
The first claim that my personal mind sets up at this point is to define the personality and cognitive functions in such a way, that all the possible psychological tests would clearly fall into either of these categories.