Alpha rhythm (8 to 12 Hz) observed in EEG over human posterior cortex is prominent during eyes-closed (EC) resting and attenuates eyes-open (EO) resting. Research shows that the degree of EC-to-EO alpha blocking or desynchronization, termed reactivity here, a neural marker cognitive health. We tested role acetylcholine by applying multimodal neuroimaging approach cohort young adults older adults. In cohort, simultaneous EEG-fMRI was recorded from twenty-one both EO EC functional MRI forty...

Abstract Attention can be attracted reflexively by sensory signals, biased learning or reward, focused voluntarily based on momentary goals. When voluntary attention is purely internal decision processes (will), rather than instructions via external cues, we call this “willed attention.” In prior work, reported ERP and fMRI correlates of willed spatial in trial-by-trial cuing tasks. Here further investigated the oscillatory mechanisms contrasting event-related EEG spectrogram between...

BackgroundPremature ventricular contraction (PVC) burden is a clinically important metric in the context of PVC-induced cardiomyopathy and commonly obtained via ambulatory ECG monitoring.ObjectiveThe purpose this analysis to characterize performance novel PVC detection algorithm capable identifying single PVCs sequences (couplets triplets) for estimation 24-hour an insertable cardiac monitor (ICM).MethodsPerformance ICM detecting was validated by replaying 748 patient-triggered ICM-recorded...

In models of visual spatial attention control, it is commonly held that top-down control signals originate in the dorsal network, propagating to cortex modulate baseline neural activity and bias sensory processing. However, precise distribution these influences across different levels hierarchy debated. addition, unclear whether changes directly translate into improved performance. We analyzed attention-related during anticipatory period a trial-by-trial voluntary task, using two independent...

Abstract The top–down control of attention involves command signals arising chiefly in the dorsal network (DAN) frontal and parietal cortex propagating to sensory enable selective processing incoming stimuli based on their behavioral relevance. Consistent with this view, DAN is active during preparatory (anticipatory) for relevant events objects, which, vision, may be defined by different stimulus attributes including spatial location, color, motion, or form. How organized support forms...

Feature-based visual attention refers to preferential selection and processing of stimuli based on their nonspatial attributes, such as color or shape. Recent studies have highlighted the inferior frontal junction (IFJ) a control region for feature but not spatial attention. However, extent which IFJ contributes versus remains topic debate. We investigated in humans both sexes role cued (attend-left attend-right) (attend-red attend-green) task using fMRI. Analyzing cue-related fMRI...

Working memory capacity (WMC) measures the amount of information that can be maintained online in face distraction. Past work has shown efficiency with which frontostriatal circuit filters out task-irrelevant distracting is positively correlated WMC. Recent demonstrated a role posterior alpha oscillations (8-13 Hz) providing sensory gating mechanism. We investigated relationship between load modulation power and WMC two verbal working experiments. In both experiments, we found increased...

A left visual field (LVF) bias in perceptual judgments, response speed, and discrimination accuracy has been reported humans. Cognitive factors, such as spatial attention, are known to modulate or even eliminate this bias. We investigated problem by recording pupillometry together with functional magnetic resonance imaging (fMRI) a cued attention task. observed that (i) the pupil was significantly more dilated following attend-right than attend-left cues, (ii) task performance (e.g. reaction...

Superior longitudinal fasciculus (SLF) is a major white matter tract connecting frontal and parietal cortices. Here we examined the role of SLF in control visual spatial attention. Diffusion MRI data were recorded from 19 subjects; same subjects, simultaneous EEG-fMRI also while they performed cued attention task. In task, each trial started with an auditory cue, directing subjects to attend left or right field. For validly trials, following random cue-target interval (CTI), two rectangles...

Top-down attention plays a vital role in selecting relevant stimuli and suppressing distracting information. During top-down visual-spatial attention, control signals from the dorsal network modulate baseline neuronal activity visual cortex favor of task-relevant stimuli. While several studies have demonstrated that shift during anticipatory occurs multiple areas, such effects not been systematically investigated across hierarchy, especially when different conditions are matched for stimulus...

ABSTRACT Feature-based attention refers to preferential selection and processing of items objects based on their non-spatial attributes such as color or shape. While it is intuitively an easier form relate in our day lives, the neural mechanisms feature-based are not well understood. Studies have long implicated dorsal network a key control system for voluntary spatial, feature object-based attention. Recent studies expanded this model by focusing inferior frontal junction (IFJ), region...

Abstract A left visual field (LVF) bias in perceptual judgements, response speed and discrimination accuracy are well documented humans. However, LVF can be modulated by task demands. For example, cuing spatial attention reduce or eliminate the bias, suggesting that attentional control compensate for bias. We investigated this possibility directly recording pupillometry together with fMRI a cued task. Prior to onset of task-relevant target stimulus, we observed pupil was significantly more...

The right hemisphere plays a dominant role in spatial cognition. Studies have shown that targets appearing the left visual field are more effectively processed than field, an effect known as bias. It is not known, however, whether such bias exists covert attention which subjects direct their voluntary to either or anticipation of target processing. We addressed this problem by measuring pupil dilation, physiological index effort, from performing cued task where they covertly focused based on...

Deploying anticipatory visual spatial attention in advance of stimulus onset enhances the processing task-relevant stimuli and suppresses distraction. In this study, we investigated neural representations control signals cortex by analyzing two fMRI datasets, one recorded at University Florida (n=13) other California, Davis (n=18), using machine learning techniques. both participants performed a cued task, which each trial began with cue, instructing subject to either attend left or right...