Complex sentence: From the 1970s onwards some psychiatrists and psychologists accused cults of harming some of their own members: accusations sometimes based on observations on therapy, sometimes related with research regarding brainwashing or mind-control.
Split into simpler sentences: From the 1970s onwards some psychiatrists and psychologists accused cults of harming some of their members. These accusations were sometimes based on observations made during therapy, and sometimes were related to research regarding brainwashing or mind-control.