Psychological Bulletin
May 14, 2012
Peter Sedlmeier, Juliane Eberth, Marcus Schwarz et al.
910 citations
A meta-analysis of 163 studies on meditation in nonclinical adults found medium average effects (r = .28) on psychological variables, not explainable by relaxation or cognitive restructuring alone. Effects were strongest for emotionality and relationships (medium to large), medium for attention, and small to medium for cognitive measures. Results varied by meditation type (transcendental, mindfulness, other). Meditation experience only partially predicted long-term impact. Most of 595 initial studies were excluded due to methodological problems, and many lacked theoretical grounding. The authors call for more precise theories and measurement tools to understand how meditation works.
Psychological Bulletin
January 1, 2005
Dieter Vaitl, Niels Birbaumer, John Gruzelier et al.
446 citations
Altered states of consciousness (ASC) can occur spontaneously, be evoked by physical or physiological stimulation, induced by psychological means, or caused by diseases. Psychological and neurobiological approaches reveal four dimensions characterizing ASC: activation, awareness span, self-awareness, and sensory dynamics. Neurophysiologically, different states of consciousness arise from compromised brain structure, transient changes in brain dynamics (disconnectivity), and neurochemical and metabolic processes. Environmental stimuli, mental practices, and self-control techniques can also temporarily alter brain functioning and conscious experience.
Psychological Bulletin
March 1, 2010
Jonathan Smallwood
173 citations
When the mind wanders, conscious thoughts arise that are only loosely related to the current task, creating tension in cognitive science because such interfering thoughts seem at odds with the assumption that they serve functional purposes. The control-failure hypothesis suggests that lapses in executive control create conditions favoring mind wandering, questioning whether it consumes resources. However, mind wandering is always a conscious, reportable experience, indicating it is globally available to the system and therefore demands resources—specifically access to a global workspace that supports conscious experience.
Psychological Bulletin
March 1, 2014
Peter Sedlmeier, Juliane Eberth, Marcus Schwarz
The authors respond to methodological criticisms of their meta-analysis on meditation's psychological effects. They defend their approach to aggregating effects across variable categories and maintain that transcendental meditation (TM) studies show some upward bias, even using the critics' preferred method. They concede they missed some TM studies but argue this omission did not alter their conclusions. The piece concludes with suggestions for improving future meditation research.
Psychological Bulletin
March 1, 2014
David W. Orme-Johnson, Michael C. Dillbeck
Reanalysis of a prior meta-analysis on meditation found that the global index used to compare meditation types was confounded because it aggregated different sets of variables for each group. When composite indices were limited to variables for which each group had at least three studies, effect sizes for the Transcendental Meditation technique were significantly larger than those for mindfulness meditation or other meditations. Quantitative tests did not indicate publication bias for any meditation type, and effect sizes did not differ between studies from researchers affiliated with a TM organization and those from other universities. The reanalysis also identified 35 missed studies on TM and several unreviewed studies on job performance, substance abuse, and prison recidivism.
Psychological Bulletin
March 1, 2011
Jonathan W. Schooler
On the centennial of William James's death, the author considers how James might have responded to Fox, Ericsson, and Best's (2011) defense of think-aloud protocols for capturing the stream of consciousness. James would likely view the procedure as scientifically rigorous introspection but would caution that it captures substantive verbal thoughts while missing inchoate cognitions. The author also notes that the conclusion that verbal protocols are nonreactive does not speak to their validity and conflicts with findings that verbalization impairs performance on some tasks. James would be pleased that introspection is finally receiving scientific grounding.