In a dark time: Development, validation, and correlates of the Durham hypnagogic and hypnopompic hallucinations questionnaire
January 1, 2009 Simon R. Jones, C. Fernyhough, D. Meads
A new questionnaire, the Durham Hypnagogic and Hypnopompic Hallucinations Questionnaire (DHQ), was developed to measure auditory, visual, and felt-presence hallucinations that occur in the transition between wakefulness and sleep. In a sample of 365 adults aged 18–29, the scale showed satisfactory psychometric properties. Among 293 participants who also completed other measures, intrusive thoughts and the conscious desire to suppress thoughts correlated only with auditory H&H hallucinations, not visual or felt-presence. Transliminality—a tendency for mental material to cross thresholds—correlated with all three subscales, but more strongly with felt-presence than visual experiences.