Mindscape Collective is now The Consciousness Library. Same library, new name. You may need to sign in again. About the change
Skip to content

Machteld Marcelis

2 papers in the library · 2 citations · publishing 2007-2025

Papers

Imagery-Focused Cognitive Behavioral Therapy Techniques for Auditory Verbal Hallucinations in Psychosis Spectrum Disorders: Four Experimental Case Series

Schizophrenia Bulletin February 21, 2025 Hella Janssen, K.C. van den Berg, Ger P. J. Keijsers et al. 2 citations

In people with psychosis spectrum disorders, maladaptive mental imagery is linked to auditory verbal hallucinations (AVHs). Four imagery techniques were tested in a single-case series: Imagery Rescripting (ImRs), Promoting positive Imagery de novo (Pos-Im), Metacognitive Imagery techniques (Meta-Im), and playing Tetris. Mental imagery severity significantly decreased after ImRs and Pos-Im, but not after Meta-Im or Tetris. AVHs decreased with all conditions, with the largest effects for ImRs and Pos-Im. Secondary measures showed reductions in AVH severity, mood, anxiety, imagery frequency, and appraisals. The authors conclude imagery techniques are feasible and acceptable and may be valuable additions to AVH treatment.

Does normal developmental expression of psychosis combine with environmental risk to cause persistence of psychosis? A psychosis proneness–persistence model

Psychological Medicine April 1, 2007 Audrey Cougnard, Machteld Marcelis, Inez Myin-Germeys et al.

Psychotic experiences (like mild hallucinations or delusions) are common and often temporary in the general population. This study tested whether they become abnormally persistent when combined with environmental factors such as cannabis use, childhood trauma, and urban living. Using two large Dutch and German population samples, the authors found that persistence rates were low overall (26% and 31%) but increased progressively with more environmental exposures. Among those exposed to both environmental risks and baseline psychotic experiences, 21%-83% (Dutch sample) and 29%-51% (German sample) had persistent symptoms due to the synergistic interaction of these factors. The authors argue that environmental risks combine additively and synergistically with non-clinical psychotic experiences to drive persistence and eventual need for care.