According to the study , almost 39 % of the people reported hallucinatory experiences . 27 % of the people reported daytime hallucinations , mostly outside the context of illness or drug use . A 1996-1999 survey of over 13,000 people reported a much higher figure , with almost 39 % of people reporting hallucinatory experiences , 27 % of which were daytime hallucinations , mostly outside the context of illness or drug use .