As the human mental activity takes a big variety of different forms, the "black box" system is adjusted to be capable to describe any kind of them. It is done through selecting different input/output systems, which supposes only the use of inputs/outputs carrying representational information and ignoring all other inputs/outputs. The famous reflex studies by I.P. Pavlov (carried on dogs because of the ethical principles) are considered to be one of the outstanding examples in experimental psychology (figure 4). 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, they may not take clinical equipment or a long learning period to proceed.
A term "psychological test" is commonly used to refer to some kind of task, which a person is supposed to do in order to estimate his/her abilities, mental health or personal qualities. This may result in a possible equalization of notions of psychological test and assessment. However in the reality a psychological test actually represents a constituent part of assessment, which may also include such components like interview, demographic and medical profile, personal history, etc. These components may be represented on their own and/or may influence the results calculation of a test or a group of tests. This point of view is one of the basic believes in the experimental psychology, what can be seen expressed in the following definitions, shared by most experts in the field of psychological assessment.
Psychological test — an objective and standardized measure of a sample of behavior — Anastasi, 1990.
Psychological assessment — an extremely complex process of solving problems (answering questions) in which psychological tests are often used as one of the methods of collecting relevant data — Maloney & Ward, 1976.
Ivan Tugoy, 2003