We used event-related fMRI to test the hypothesis that preparatory attention modulations occur in higher-order motion-processing regions when subjects deploy attention to internally driven representations in a complex motion-processing task. Using a cued attention-to-motion task, we found preparatory increases in fMRI activity in visual motion regions in the absence of visual motion stimulation. The cue, a brief enlargement of the fixation cross, directed subjects to prepare for a complex motion discrimination task. This preparation activated higher-order and lower-order motion regions. The motion regions activated included temporal regions consistent with V5/MT+, occipital regions consistent with V3+, parietal-occipital junction regions, ventral and dorsal intraparietal sulcus, superior temporal sulcus (STS), posterior insular cortex (PIC), and a region of BA 39/40 superior to V5/MT+ involving the angular gyrus and supramarginal gyrus (A-SM). Consistent with our hypothesis that these motion sensory activations are under top-down control, we also found activation of an extensive frontal network during the cue period, including anterior cingulate and multiple prefrontal regions. These results support the hypothesis that anticipatory deployment of attention to internally driven representations is achieved via top-down modulation of activity in task-relevant processing areas.
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http://dx.doi.org/10.1016/j.neuroimage.2004.04.008 | DOI Listing |
Alzheimers Dement
December 2024
University of Toronto, Toronto, ON, Canada.
Background: Commercially available exercise video games ('exergames') can be used by people with dementia with the right (human) prompting and support. However, more information is needed about what makes these systems and games technologically accessible for this population, considering their cognitive difficulties. This study explores what works and doesn't work for people with dementia when introducing new exergame systems and games to broaden opportunities for physical activity.
View Article and Find Full Text PDFHum Brain Mapp
January 2025
The Mind Research Network/Lovelace Biomedical Research Institute, Albuquerque, New Mexico, USA.
Evaluation of mechanisms of action of EEG neurofeedback (EEG-nf) using simultaneous fMRI is highly desirable to ensure its effective application for clinical rehabilitation and therapy. Counterbalancing training runs with active neurofeedback and sham (neuro)feedback for each participant is a promising approach to demonstrate specificity of training effects to the active neurofeedback. We report the first study in which EEG-nf procedure is both evaluated using simultaneous fMRI and controlled via the counterbalanced active-sham study design.
View Article and Find Full Text PDFRespir Res
January 2025
Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Department of Biomedical Engineering, Air Force Medical University, Xi'an, 710032, China.
Background: Acute pulmonary embolism represents the third most prevalent cardiovascular pathology, following coronary heart disease and hypertension. Its untreated mortality rate is as high as 20-30%, which represents a significant threat to patient survival. In view of the current lack of real-time monitoring techniques for acute pulmonary embolism, this study primarily investigates the potential of the pulsatility electrical impedance tomography (EIT) technique for the detection and real-time monitoring of acute pulmonary embolism through the collection and imaging of the pulsatile signal of pulmonary blood flow.
View Article and Find Full Text PDFJ Neurosci
January 2025
Wellcome Centre for Integrative Neuroimaging; Nuffield Department of Clinical Neuroscience, University of Oxford.
Damage to the primary visual cortex (V1) results in visual field deficits on the contralateral side of the world corresponding to the damaged region. Patients with such loss nonetheless show varying residual vision within this apparently blind region, with the neural mechanisms underlying this ability obscured by small study populations. We identified lesions on structural scans from 39 patients (12 female) with hemianopia and occipital lobe damage.
View Article and Find Full Text PDFSaudi Med J
January 2025
From the Physiotherapy Department (R. Alfaifi, Juraybi, Alrashed, Alghidani) Al-Rass General Hospital, Al-Rass; from the Neurosurgery Department (H. Alfaifi), Abha Maternity and Child Hospital, Abha, Kingdom of Saudi Arabia.
Objectives: To investigate the long-term effects of Extracorporeal shockwave therapy (ESWT) and ultrasound (US) in treating the trigger finger. Trigger finger, also known as stenosing tenosynovitis, is a common type of tenosynovitis affecting the flexor sheath of any finger. Extracorporeal shockwave therapy and therapeutic US are conservative treatments that use waves of varied frequency to target damaged regions and improve function.
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