Detection of Leak From Left Atrial Appendage Occlusion Using Dielectric Imaging.

Background: Peri-device leak (PDL) following left atrial appendage occlusion (LAAO) may lead to an increased risk of thrombosis. However, current modalities for PDL detection, such as trans-esophageal echo (TEE) and cardiac CT do not provide quantitative measures of PDL.

Objective: to use dielectric imaging (DI) to measure PDL from a Watchman (WM) LAAO device.

Visual detection of time-varying signals: Opposing biases and their timescales.

Human visual perception is a complex, dynamic and fluctuating process. In addition to the incoming visual stimulus, it is affected by many other factors including temporal context, both external and internal to the observer. In this study we investigate the dynamic properties of psychophysical responses to a continuous stream of visual near-threshold detection tasks.

Plasticity compartments in basal dendrites of neocortical pyramidal neurons.

Synaptic plasticity rules widely determine how cortical networks develop and store information. Using confocal imaging and dual site focal synaptic stimulation, we show that basal dendrites, which receive the majority of synapses innervating neocortical pyramidal neurons, contain two compartments with respect to plasticity rules. Synapses innervating the proximal basal tree are easily modified when paired with the global activity of the neuron.