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“In earlier papers I reported findings of anthropological fieldwork in India, in which I found highly experienced yogis who had dual personalities, religious auditory and visual hallucinations, and beliefs in their own spiritual powers such as the ability to control the weather, or walk on water (Castillo 1991a, 1991b, 1995, 1997b, 2001). These findings were based on extended observations and interactions with six yogis, brief interviews with twenty-one, and casual observations of a few hundred yogis in the Himalayan region of Uttar Pradesh, India, where I lived among them for a period of 10 months.”

“In these individuals, many years of meditative trance seems to have produced a state of permanently altered consciousness characterized by divided consciousness and recurrent religious visions and beliefs that would be considered delusional in a modern Western culture. All of these yogis had been practicing meditation for at least 10 years, and some for decades. I suggested that it was the extensive meditation and the Hindu cultural context that was responsible for these altered states of consciousness and religious beliefs.”

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“In my studies of meditative trance (Castillo 1990, 1991a), I found that meditation practice intensively can result in states of consciousness that in psychiatric setting might be considered experiences of negative psychotic symptoms. These included affective flattening, reduction in the amount of thought and speech (alogia), and reduction in goal directed activity (avolition).”