J Psychiatry Neurosci 2011;36(6):366-74
Nadine Donata Wolf, MD; Fabio Sambataro, MD, PhD; Nenad Vasic, MD; Karel Frasch, MD; Markus Schmid, MD; Carlos Schönfeldt-Lecuona, MD; Philipp Arthur Thomann, MD; Robert Christian Wolf, MD
N.D. Wolf — Central Institute of Mental Health, Department of Addictive Behavior and Addiction Medicine, Mannheim, Germany; Sambataro — Brain Center for Motor and Social Cognition, Italian Institute of Technology, Parma, Italy; Vasic, Schmid, Schönfeldt-Lecuona, R.C. Wolf — Department of Psychiatry and Psychotherapy III, University of Ulm, Germany; Frasch — Department of Psychiatry and Psychotherapy II, University of Ulm, Germany; Thomann, R.C. Wolf — Center of Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Germany
Background: Functional neuroimaging studies on schizophrenia have suggested abnormal task-related functional connectivity in patients with schizophrenia who have auditory verbal hallucinations (AVHs). However, little is known about intrinsic functional connectivity in these patients.
Methods: Between January 2009 and February 2010, we studied patients with schizophrenia who had persistent and treatment-refractory AVHs in comparison with healthy controls. Using functional magnetic resonance imaging, we studied the functional connectivity of multiple resting state networks (RSNs) and their relation to symptom severity. We analyzed the data using a spatial group independent component analysis, and we used random-effects t tests to compare spatial components between groups.
Results: There were 10 patients and 14 controls enrolled in this study. In total, 16 RSNs were identified, from which we selected 4 networks of interest for further analyses. Within a speech-related network, patients showed increased connectivity in bilateral temporal regions and decreased connectivity in the cingulate cortex. Within 2 additional RSNs associated with attention and executive control, respectively, patients exhibited abnormal connectivity in the precuneus and right lateral prefrontal areas. We found correlations between measures of AVH severity and functional connectivity of the left anterior cingulate, left superior temporal gyrus and right lateral prefrontal cortex.
Limitations: The relatively small sample size, the patients’ use of antipsychotic medication and the lack of a clinical control group have to be considered as potential limitations.
Conclusion: Our findings indicate that disrupted intrinsic connectivity of a speech-related network could underlie persistent AVHs in patients with schizophrenia. In addition, the occurrence of hallucinatory symptoms seems to modulate RSNs associated with attention and executive control.
Submitted Jan. 26, 2011; Revised Mar. 27, Apr. 17, 2011; Accepted Apr. 19, 2011.
Acknowledgments: This work was supported by a research grant from the University of Ulm, Germany (principal investigator R.C.W.). The authors thank all participants and their families for their time and interest in this study. The authors are grateful to Miriam Ott and Petra Neumann for their assistance with data collection.
Competing interests: None declared from Drs. N.D. Wolf, Sambataro, Vasic, Schmid, Schönfeldt-Lecuona, Thomann and R.C. Wolf. Dr. Frasch declares having received grant support from AstraZeneca, lecture fees from Janssen and travel support from AstraZeneca, Janssen, Lilly and Pfizer; and holds stock in STADA.
Contributors: Drs. N.D. Wolf, Sambataro, R.C. Wolf, Vasic and Schönfeldt-Lecuona designed the study. Drs. N.D. Wolf, R.C. Wolf, Vasic, Frasch and Schmid acquired the data. Drs. N.D. Wolf, Sambataro, R.C. Wolf and Thomann analyzed the data. Drs. N.D. Wolf and R.C. Wolf wrote the article, which Drs. N.D. Wolf, Sambataro, R.C. Wolf, Vasic, Frasch, Schmid, Schönfeldt-Lecuona and Thomann reviewed. All authors approved publication.
Correspondence to: Dr. R.C. Wolf, Center of Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Germany, Voßstraße 4, 69115 Heidelberg, Germany; firstname.lastname@example.org