Schizophrenia Bulletin Advance Access originally published online on June 7, 2007
Schizophrenia Bulletin 2007 33(4):1004-1012; doi:10.1093/schbul/sbm052
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Spontaneous Low-Frequency Fluctuations in the BOLD Signal in Schizophrenic Patients: Anomalies in the Default Network
2 Department of Psychiatry
3 Department of Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Canada
4 Hotel Dieu, Kingston, Canada
5 Department of Psychology, University of Western Ontario, London, Canada
1 To whom correspondence should be addressed; Tanna Schulich Chair in Neuroscience & Mental Health, University Campus—LHSC, 339 Windermere Road, London, Canada N6A 5A5, tel: 519-663-3032, fax: 519-663-3935, e-mail: williams{at}uwo.ca.
Spontaneous low-frequency fluctuations in the blood oxygen level–dependent (BOLD) functional magnetic resonance imaging (MRI) signal have been shown to reflect neural synchrony between brain regions. A "default network" of spontaneous low-frequency fluctuations has been described in healthy volunteers during stimulus-independent thought. Negatively correlated with this network are regions activated during attention-demanding tasks. Both these networks involve brain regions and functions that have been linked with schizophrenia in previous research. The present study examined spontaneous slow fluctuations in the BOLD signal at rest, as measured by correlation with low-frequency oscillations in the posterior cingulate, in 17 schizophrenic patients, and 17 comparable healthy volunteers. Healthy volunteers demonstrated correlation between spontaneous low-frequency fluctuations of the BOLD signal in the posterior cingulate and fluctuations in the lateral parietal, medial prefrontal, and cerebellar regions, similar to previous reports. Schizophrenic patients had significantly less correlation between spontaneous slow activity in the posterior cingulate and that in the lateral parietal, medial prefrontal, and cerebellar regions. Connectivity of the posterior cingulate was found to vary with both positive and negative symptoms in schizophrenic patients. Because these data suggest significant abnormalities in resting-state neural networks in schizophrenia, further investigations of spontaneous slow fluctuations of the BOLD signal seem warranted in this population.
Keywords: anticorrelated networksdefault network / schizophrenia / functional MRI / spontaneous slow fluctuations / posterior cingulate / medial prefrontal cortex
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  Y. Liu, M. Liang, Y. Zhou, Y. He, Y. Hao, M. Song, C. Yu, H. Liu, Z. Liu, and T. Jiang Disrupted small-world networks in schizophrenia Brain, April 1, 2008; 131(4): 945 - 961. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. L. BUCKNER, J. R. ANDREWS-HANNA, and D. L. SCHACTER The Brain's Default Network: Anatomy, Function, and Relevance to Disease Ann. N.Y. Acad. Sci., March 1, 2008; 1124(1): 1 - 38. [Abstract] [Full Text] [PDF]
|
|