Criticisms

While most would agree that the birth of psychology as a science took place
in Leipzig, Germany, in 1879, whenWilhelmWundt established the first laboratory
for studying psychological phenomena, there is no clear record of
the first use of experimentation. Regardless, there is no disputing the attraction
that this method of research has had for many psychologists in the twentieth
century. Psychologists clearly recognize the usefulness of the experiment
in investigating potential causal relationships between variables.
Hence, experimentation is employed widely across the subfields of psychology,
including developmental, cognitive, physiological, clinical, industrial,
and social psychology.

This is not to say that all psychologists are completely satisfied with experimental
research. It has been argued that an insidious catch-22 exists in
some experimental research that limits its usefulness. The argument goes
like this: Experimenters are motivated to control rigorously the conditions
of their studies and the relevant extraneous variables. To gain such control,
they often conduct experiments in a laboratory setting. Therefore, subjects
are often observed in an artificial environment, engaged in behaviors that
are so controlled as to be unnatural, and they clearly know they are being
observed—which may further alter their behavior. Such research is said to
be lacking in ecological validity or applicability to “real-life” behavior. It may
show how subjects behave in a unique laboratory procedure, but it tells little
about psychological phenomena as displayed in everyday life. The catch-22, then, is that experimenters desire control in order to establish that the independent
variable is producing a change in the dependent variable, and the
more such control, the better; however, the more control, the more risk that
the research may be ecologically invalid.