Journal of Cognitive Neuroscience
Functional Changes in Brain Activity During Priming in Alzheimer’s Disease
Journal of Cognitive Neuroscience
Journal of Cognitive Neuroscience
Learning class-discriminative dynamic Bayesian networks
ICML '05 Proceedings of the 22nd international conference on Machine learning
Age-related Changes in Brain Activity across the Adult Lifespan
Journal of Cognitive Neuroscience
The BOLD Hemodynamic Response in Healthy Aging
Journal of Cognitive Neuroscience
Working Memory for Complex Scenes: Age Differences in Frontal and Hippocampal Activations
Journal of Cognitive Neuroscience
Age-related Changes in Object Processing and Contextual Binding Revealed Using fMR Adaptation
Journal of Cognitive Neuroscience
Age Differences in Deactivation: A Link to Cognitive Control?
Journal of Cognitive Neuroscience
Journal of Biomedical Imaging - Recent Advances in Neuroimaging Methodology
Shrinkage Estimator for Bayesian Network Parameters
ECML '07 Proceedings of the 18th European conference on Machine Learning
A six stage approach for the diagnosis of the Alzheimer's disease based on fMRI data
Journal of Biomedical Informatics
Journal of Cognitive Neuroscience
Artificial Intelligence in Medicine
Improving bayesian network structure search with random variable aggregation hierarchies
ECML'06 Proceedings of the 17th European conference on Machine Learning
ICONIP'11 Proceedings of the 18th international conference on Neural Information Processing - Volume Part I
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Brain imaging based on functional MRI (fMRI) provides a powerful tool for characterizing age-related changes in functional anatomy. However, between-population comparisons confront potential differences in measurement properties. The present experiment explores the feasibility of conducting fMRI studies in nondemented and demented older adults by measuring hemodynamic response properties in an event-related design. A paradigm involving repeated presentation of sensory-motor response trials was administered to 41 participants (14 young adults, 14 nondemented older adults, and 13 demented older adults). For half of the trials a single sensory-motor event was presented in isolation and in the other half in pairs. Hemodynamic response characteristics to the isolated events allowed basic response properties (e.g., amplitude and variance) between subject groups to be contrasted. The paired events further allowed the summation properties of the hemodynamic response to be characterized. Robust and qualitatively similar activation maps were produced for all subject groups. Quantitative results showed that for certain regions, such as in the visual cortex, there were marked reductions in the amplitude of the hemodynamic response in older adults. In other regions, such as in the motor cortex, relatively intact response characteristics were observed. These results suggest caution should be exhibited in interpreting simple main effects in response amplitude between subject groups. However, across all regions examined, the summation of the hemodynamic response over trials was highly similar between groups. This latter finding suggests that, even if absolute measurement differences do exist between subject groups, relative activation change should be preserved. Designs that rely on group interactions between task conditions, parametric manipulations, or group interactions between regions should provide valuable data for making inferences about functional-anatomic changes between different populations.