Descriptions of the astral plane : comment on Ferreira (2013)

I've spent some time working with various spirit mediums, not that I'm a seer myself, or have any pretensions (or interest) to be one. I'm simply curious in their claims of interaction with invisible 'presences'. Just what these alleged presences are I'll never be sure, despite plenty of interesting events occurring when I've watched their work. I can only rely on the mediums' own descriptions of what they claim to see and their explanations for what these impressions are (that's why they are mediums, I guess). The mediums themselves describe their experiences using ordinary language. For example, they might convey something general and 'psychical', such as; "There's a lot of movement along the corridor" of an abandoned psychiatric hospital. Or they might make more specific statements such as; "I see an active male presence walking up and down the hospital corridor. They're a former patient.'