According to developmental psychology, it is impossible to pinpoint definite ages when certain changes take place. We are all different and grow at varying speeds. So what is meant by “age”? We have a chronological age but we also have several types of ages based on our physical and psychological development.
In a study of the aging process, Robert Kastenbaum examined these various ‘age groups’. In addition, he asked about the subjective age that we feel, which he found tended to be younger than our objective age, especially as we got older. He also found that our subjective age was often lower than our biological age, determined by the state of our body and face, either by ourselves or others, our functional age, based on our interests and activities, as well as our social status, which was judged by our position in society, and our cultural age, which was determined by our knowledge and understanding of culture. The study revealed that these age groups had a broad range, illustrating the truism that we’re only as old as we think.