Much, almost all psychological research has been conducted on students. It is for university professors the easiest way: students are at hand, no travelling required, students are cheap and available at convenient times, etc.
I have never seen psychological research of elderly other than research related to mental problems of elderly. I never came across standard psychological research (about perception, mental functions, cognition and behavior) among scientists, plumbers, shop owners, nurses, train drivers or in general people older than 25 years. If there were any, I bet that the research was conducted by written surveys, a not all too reliable method of gathering scientific insights because people tend to respond what is social acceptable. Also, there is quiet a difference between what people say about themselves as what they actually do. Students can be observed without much effort.
Of course, there are many research papers on therapeutic issues that involve non-students, but the majority of general knowledge in the field of psychology is derived from students at universities.
Students come mostly from middle class families, with a moderate income. They are between 18 and 24 year, at age the brain is yet not matured. They might act much more impulsive than people in another life phase. In Erikson’s stages of psychosocial development they are still wrestling with existential questions as Who Am I and What Can I Be and Can I Love? It seems to me that those issues as identity or role confusion and intimacy versus isolation must influence research outcomes and therefore can not be generalized to a whole population.
Students have not reached the phase of Grihastha, the second phase of an individual’s life in the Hindu ashram system. It is often called ‘the householders life’ revolving as it does around the duties of maintaining a household and leading a family centred life. In Erikson’s ideas middle-adults have transcended the wish to blend their identities with friends and wanting to fit in. They have another attitude about life. They want to contribute.
Students have already been in a school system. School systems are by itself total institutions. A total institution is a place of work and residence where a great number of similarly situated people, cut off from the wider community for a considerable time, together lead an enclosed, formally administered round of life. In order to function schools have a need to homogenizing behavior. By the time they are locked up in schools for more than 12 years that behavior will undoubtedly be internalized, and as such will influence any psychological research that is conducted with young adults.
We need to be very careful with psychological research, and thus with psychologists who claim to work scientifically. It is better to say: psychological research has shown that young students tend to behave in circumstances like… etc. There is a huge bias in psychological research. Many psychologists operate in a young-adult logic bubble.
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