Methods for diagnosis and treatment of stimulus-correlated motion in generic brain activation studies using fMRI

Bullmore, Edward T.; Brammer, Michael; Rabe‐Hesketh, Sophia; Curtis, Vivienne; Morris, Robin G.; Williams, Steven; Sharma, Tonmoy; McGuire, Philip

doi:10.1002/(sici)1097-0193(1999)7:1<38::aid-hbm4>3.0.co;2-q

Cited by 426 publications

(187 citation statements)

References 9 publications

Supporting

Mentioning

184

Contrasting

Order By: Relevance

“…2c), a phenomenon previously described (Rombouts et al, 1998;Bullmore et al, 1999;Thacker et al, 1999). Other significant components were weighted heavily in occipital regions (overlapping with the component in Fig.…”

Section: Resultssupporting

confidence: 60%

Deterministic and stochastic features of fMRI data: implications for analysis of event-related experiments

McKeown

Varadarajan

Huettel

et al. 2002

Journal of Neuroscience Methods

View full text Add to dashboard Cite

As the limits of stimuli presentation rates are explored in event-related fMRI design, there is a greater need to assess the implications of averaging raw fMRI data. Selective averaging assumes that the fMRI signal consists of task-dependent signal, random noise, and non-task dependent brain signal that can be modeled as random noise so that it tends to zero when averaged over a practical number of trials. We recorded a total of four fMRI data series from two normal subjects (subject 1, axially acquired; subject 2, coronally acquired) performing a simple visual event-related task and a water phantom with the same fMRI scanner imaging parameters. To determine which fraction of the fMRI data was deterministic as opposed to random, we created different data subsets by taking the odd or even time points of the full data sets. All data sets were first dimension-reduced with principal component analysis (PCA) and separated into 100 spatially independent components with independent component analysis (ICA). The mutual information between best-matching pairs of components selected from full data set Á/subset comparisons was plotted for each data set. Visual inspection suggested that 45 Á/85 components were reproducible, and hence deterministic, accounting for 79 Á/ 97% of the variance, respectively, in the raw data. The reproducible components exhibited much less trial-to-trial variability than the raw data from even the most activated voxel. Many (22 Á/47) of reproducible components were significantly affected by stimulus presentation (P B/0.001). The most significantly-stimulus-correlated component was strongly time-locked to stimulus presentation and was directly stimulus correlated, corresponding to occipital brain regions. However, other spatially distinct task-related components demonstrated variable temporal relationships with the most significantly stimulus-correlated component. Our results suggest that the majority of the variance in fMRI data is in fact deterministic, and support the notion that the data consist of differing components with differing temporal relationships to visual stimulation. They further suggest roles for restricting interpretations of the spatial extent of activation from event-related designs to a specific region of interest (ROI) and/or first separating the data into spatially independent components. Averaging the time courses of spatially independent components timelocked to stimulus presentation may prevent possible biases in the estimates of the spatial and temporal extent of stimulus-correlated activation and of trial-to-trial variability. #

show abstract

Section: Resultssupporting

confidence: 60%

Deterministic and stochastic features of fMRI data: implications for analysis of event-related experiments

McKeown

Varadarajan

Huettel

et al. 2002

Journal of Neuroscience Methods

View full text Add to dashboard Cite

show abstract

“…Data were first corrected for subject motion 31 and then smoothed using a Gaussian filter (full-width at halfmaximum 7.2 mm) chosen to improve signal-to-noise ratio over the spatial neighborhood of each voxel. Responses to the experimental paradigms were then detected by time series analysis using a linear model in which each component of the experimental design was convolved separately with two g variate functions (peak responses at 4 and 8 s, respectively) to permit variability in the hemodynamic delay.…”

Section: Discussionmentioning

confidence: 99%

To discard or not to discard: the neural basis of hoarding symptoms in obsessive-compulsive disorder

et al. 2008

View full text Add to dashboard Cite

Preliminary neuroimaging studies suggest that patients with the 'compulsive hoarding syndrome' may be a neurobiologically distinct variant of obsessive-compulsive disorder (OCD) but further research is needed. A total of 29 OCD patients (13 with and 16 without prominent hoarding symptoms) and 21 healthy controls of both sexes participated in two functional magnetic resonance imaging experiments consisting of the provocation of hoarding-related and symptom-unrelated (aversive control) anxiety. In response to the hoarding-related (but not symptom-unrelated) anxiety provocation, OCD patients with prominent hoarding symptoms showed greater activation in bilateral anterior ventromedial prefrontal cortex (VMPFC) than patients without hoarding symptoms and healthy controls. In the entire patient group (n = 29), provoked anxiety was positively correlated with activation in a frontolimbic network that included the anterior VMPFC, medial temporal structures, thalamus and sensorimotor cortex. Negative correlations were observed in the left dorsal anterior cingulate gyrus, bilateral temporal cortex, bilateral dorsolateral/medial prefrontal regions, basal ganglia and parieto-occipital regions. These results were independent from the effects of age, sex, level of education, state anxiety, depression, comorbidity and use of medication. The findings are consistent with the animal and lesion literature and several landmark clinical features of compulsive hoarding, particularly decision-making difficulties. Whether the results are generalizable to hoarders who do not meet criteria for OCD remains to be investigated.

show abstract

“…Typically, psychosis begins in early adulthood and interferes with education, employment, and social functioning. A hereditary contribution has been established beyond doubt, and neuroimaging and neuropathological studies show subtle brain abnormalities (1)(2)(3). The dorsal prefrontal cortex has been particularly implicated in the pathophysiological dysfunction in schizophrenia (4,5).…”

mentioning

confidence: 99%

Gene expression analysis in schizophrenia: Reproducible up-regulation of several members of the apolipoprotein L family located in a high-susceptibility locus for schizophrenia on chromosome 22

Mimmack

Ryan

Baba

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

167

View full text Add to dashboard Cite

We screened a custom-made candidate gene cDNA array comprising 300 genes. Genes chosen have either been implicated in schizophrenia, make conceptual sense in the light of the current understanding of the disease, or are located on high-susceptibility chromosome locations. The array screen using prefrontal cortex tissue from 10 schizophrenia and 10 control brains revealed robust up-regulation of apolipoprotein L1 (apo L1) by 2.6-fold. The finding was cross-validated in a blinded quantitative PCR study using prefrontal cortex tissue from the Stanley Foundation brain collection, Bethesda, MD. This collection consists of 15 schizophrenia, 15 bipolar disorder, 15 major depression, and 15 control individuals, all 60 brains being well-matched on conventional parameters, with antipsychotic drug exposure in the schizophrenia and bipolar disorder groups. Significant up-regulation of apo L1 gene expression in schizophrenia was confirmed. Using quantitative PCR, expression profiles of other members of the apo L family (apo L2-L6) were investigated, showing that apo L2 and L4 were highly significantly up-regulated in schizophrenia. Results were then confirmed in an independent set of 20 schizophrenia and 20 control brains from Japan and New Zealand. Apo L proteins belong to the group of high density lipoproteins, with all six apo L genes located in close proximity to each other on chromosome 22q12, a confirmed high-susceptibility locus for schizophrenia and close to the region associated with velocardiofacial syndrome that includes symptoms of schizophrenia.

show abstract

Methods for diagnosis and treatment of stimulus-correlated motion in generic brain activation studies using fMRI

Cited by 426 publications

References 9 publications

Deterministic and stochastic features of fMRI data: implications for analysis of event-related experiments

Deterministic and stochastic features of fMRI data: implications for analysis of event-related experiments

To discard or not to discard: the neural basis of hoarding symptoms in obsessive-compulsive disorder

Gene expression analysis in schizophrenia: Reproducible up-regulation of several members of the apolipoprotein L family located in a high-susceptibility locus for schizophrenia on chromosome 22

Contact Info

Product

Resources

About