With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: A 2011 prospective study by Roland R. Griffiths and colleagues suggests that a single high dosage of psilocybin can cause long-term changes in the personality of its users. About half of the study participants—described as healthy, "spiritually active", and many possessing postgraduate degrees—showed an increase in the personality dimension of openness (assessed using the Revised NEO Personality Inventory), and this positive effect was apparent more than a year after the psilocybin session. According to the study authors, the finding is significant because "no study has prospectively demonstrated personality change in healthy adults after an experimentally manipulated discrete event." A further study by Griffiths in 2017 found that doses of 20 to 30 mg/70 kg psilocybin inducing mystical-type experiences brought more lasting changes to traits including altruism, gratitude, forgiveness and feeling close to others when they were combined with a regular meditation practice and an extensive spiritual practice support programme. Although other researchers have described instances of psychedelic drug usage leading to new psychological understandings and personal insights, it is not known whether these experimental results can be generalized to larger populations.
text_B: Could a researcher cite the 2011 study as an example of the positive effects of psilocybin to personality changes?
YES.