Local field potential phase modulates the evoked response to electrical stimulation in visual cortex.

Development of cortical visual prostheses requires optimization of evoked responses to electrical stimulation to reduce charge requirements and improve safety, efficiency, and efficacy. One promising approach is timing stimulation to the local field potential (LFP), where action potentials have been found to occur preferentially at specific phases. To assess the relationship between electrical stimulation and the phase of the LFP, we recorded action potentials from primary (V1) and secondary (V2) visual cortex in marmosets while delivering single-pulse electrical microstimulation at different phases of the local field potential.

Modeling PET Data Acquired During Nonsteady Conditions: What If Brain Conditions Change During the Scan?

Researchers use dynamic PET imaging with target-selective tracer molecules to probe molecular processes. Kinetic models have been developed to describe these processes. The models are typically fitted to the measured PET data with the assumption that the brain is in a steady-state condition for the duration of the scan.

A deep neural network for positioning and inter-crystal scatter identification in multiplexed PET detectors: a simulation study.

High-resolution positron emission tomography (PET) relies on the accurate positioning of annihilation photons impinging the crystal array. However, conventional positioning algorithms in light-sharing PET detectors are often limited due to edge effects and/or the absence of additional information for identifying and correcting scattering within the crystal array (known as inter-crystal scattering). This study explores the feasibility of deep neural network (DNN) techniques for more precise event positioning in finely segmented and highly multiplexed PET detectors with light-sharing.

Virtual cylindrical PET for efficient DOI image reconstruction with sub-millimetre resolution.

Image reconstruction in high resolution, narrow bore PET scanners with depth of interaction (DOI) capability presents a substantial computational challenge due to the very high sampling in detector and image space. The aim of this study is to evaluate the use of a virtual cylinder in reducing the number of lines of response (LOR) for DOI-based reconstruction in high resolution PET systems while maintaining uniform sub-millimetre spatial resolution.Virtual geometry was investigated using the awake animal mousePET as a high resolution test case.