Functional MR imaging of confounded hypofrontality
β Scribed by Edward Bullmore; Mick Brammer; Steve C.R. Williams; Vivienne Curtis; Philip McGuire; Robin Morris; Robin Murray; Tonmoy Sharma
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 164 KB
- Volume
- 8
- Category
- Article
- ISSN
- 1065-9471
No coin nor oath required. For personal study only.
β¦ Synopsis
Comparatively reduced blood flow to frontal brain regions in patients with schizophrenia (hypofrontality) has been frequently observed in the last 25 years. However, there is an inconstant quality to hypofrontality, suggesting either confounded observation of a static (trait-like) abnormality, or that it is a genuinely dynamic (state-like) phenomenon. Possible confounds in functional magnetic resonance imaging (fMRI) studies of hypofrontality are classified. Methods for assessment and correction of stimulus correlated motion (an extracerebral confound) are reviewed in the context of fMRI data acquired from five schizophrenic patients and five comparison subjects during performance of a verbal fluency task. Factorial analysis of these and other data, acquired from the same subjects during a semantic decision task, is used to exclude a number of possible intracerebral confounds. By analogy to the historical controversy concerning the appearance of the planet Saturn viewed through early telescopes, understanding the inconstancy of hypofrontality in schizophrenia is likely to progress more by theoretically driven experiments that exploit the repeatability of fMRI than by further technological development alone.
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