According to Caroline Watt (2005), an eminent specialist, parapsychology has made a significant contribution to the fields of mainstream science and psychology. These have benefited for two main reasons.
Firstly, parapsychology has focused attention on aspects of the mind that have subsequently become the subject of conventional scientific research, such as consciousness, perception and memory. Another point is that the boundaries of psychology have been consistently expanded. For example, early experiments into mesmerism, now better known as hypnosis, were carried out by psychical researchers. Nowadays, hypnosis is a recognized mental phenomenon. Watt mentions, moreover, that recent parapsychological research into anomalous events like out-of-body experiences has led to greater understanding in the areas of conventional psychology.
Secondly, since paranormal phenomena are notoriously difficult to prove, over the years, investigators in this field have developed meticulous methods of research into mental processes. As a result, mainstream psychology has been able to widen its range of experimental procedures. One example of this is the popularization of blind testing which was used to reduce bias in early experiments on psychic ability. However, issues related to repeatability and methods of data analysis continue to challenge professionals in both parapsychology and mainstream psychology.