The present study aimed at examining the validity of the use of the psychological distance map (PDM) for assessing the interpersonal psychological distances, and also examined whether subject's interpersonal environment would be organized through a microgenetic developmental course during the critical transition, i.e. admissions to a university (NE). Assessments were made 18 times after admissions by (1) the PDM, (2) a rating scale for psychological distance, and (3) personal interviews. Results showed that psychological distances on the PDM correlated significantly with those of the rating scale, and that the specific spatial layout on the PDM related to those interpersonal relationships on the PDM. It was also found that, while the number of persons in the NE increased, the number of persons from the old environment (OE) decreased. NE entries came significantly close to the center of the PDM, but no significant change was observed among those in the OE. Both the numbers of connections among persons in the NE and of those between persons in the NE and the OE increased over trials. These results were discussed from a microgenetic developmental view point.
