Tele-Neuro-Ophthalmology During the Age of COVID-19.

Supplemental Digital Content is Available in the Text.

Colored floaters as a manifestation of digoxin toxicity.

Purpose: Since its report in one patient more than 70 years ago, digitalis-induced colored muscae volitantes have not surfaced again in the literature. We report here a case of digoxin induced colored floaters.

Observations: An 89-year-old man on 0.

Corollary Discharge and Oculomotor Proprioception: Cortical Mechanisms for Spatially Accurate Vision.

A classic problem in psychology is understanding how the brain creates a stable and accurate representation of space for perception and action despite a constantly moving eye. Two mechanisms have been proposed to solve this problem: Herman von Helmholtz's idea that the brain uses a corollary discharge of the motor command that moves the eye to adjust the visual representation, and Sir Charles Sherrington's idea that the brain measures eye position to calculate a spatial representation. Here, we discuss the cognitive, neuropsychological, and physiological mechanisms that support each of these ideas.

Hippocampal CA3 NMDA receptors are crucial for memory acquisition of one-time experience.

Lesion and pharmacological intervention studies have suggested that in both human patients and animals the hippocampus plays a crucial role in the rapid acquisition and storage of information from a novel one-time experience. However, how the hippocampus plays this role is poorly known. Here, we show that mice with NMDA receptor (NR) deletion restricted to CA3 pyramidal cells in adulthood are impaired in rapidly acquiring the memory of novel hidden platform locations in a delayed matching-to-place version of the Morris water maze task but are normal when tested with previously experienced platform locations.

Requirement for hippocampal CA3 NMDA receptors in associative memory recall.

Pattern completion, the ability to retrieve complete memories on the basis of incomplete sets of cues, is a crucial function of biological memory systems. The extensive recurrent connectivity of the CA3 area of hippocampus has led to suggestions that it might provide this function. We have tested this hypothesis by generating and analyzing a genetically engineered mouse strain in which the N-methyl-D-asparate (NMDA) receptor gene is ablated specifically in the CA3 pyramidal cells of adult mice.