Running speed and REM sleep control two distinct modes of rapid interhemispheric communication.

Rhythmic gamma-band communication within and across cortical hemispheres is critical for optimal perception, navigation, and memory. Here, using multisite recordings in both rats and mice, we show that even faster ∼140 Hz rhythms are robustly anti-phase across cortical hemispheres, visually resembling splines, the interlocking teeth on mechanical gears. Splines are strongest in superficial granular retrosplenial cortex, a region important for spatial navigation and memory.

Pan-Genotypic Direct-Acting Antiviral Agents for Undetermined or Mixed-Genotype Hepatitis C Infection: A Real-World Multi-Center Effectiveness Analysis.

Although the pan-genotypic direct-acting antiviral regimen was approved for treating chronic hepatitis C infection regardless of the hepatitis C virus (HCV) genotype, real-world data on its effectiveness against mixed-genotype or genotype-undetermined HCV infection are scarce. We evaluated the real-world safety and efficacy of two pan-genotypic regimens (Glecaprevir/Pibrentasvir and Sofosbuvir/Velpatasvir) for HCV-infected patients with mixed or undetermined HCV genotypes from the five hospitals in the Changhua Christian Care System that commenced treatment between August 2018 and December 2020. This retrospective study evaluated the efficacy and safety of pan-genotypic direct-acting antiviral (DAA) treatment in adults with HCV infection.

Functional Differentiation of Dorsal and Ventral Posterior Parietal Cortex of the Rat: Implications for Controlled and Stimulus-Driven Attention.

The posterior parietal cortex (PPC) is important for visuospatial attention. The primate PPC shows functional differentiation such that dorsal areas are implicated in top-down, controlled attention, and ventral areas are implicated in bottom-up, stimulus-driven attention. Whether the rat PPC also shows such functional differentiation is unknown.

Neuronal Activity in the Rat Pulvinar Correlates with Multiple Higher-Order Cognitive Functions.

The pulvinar, also called the lateral posterior nucleus of the thalamus in rodents, is one of the higher-order thalamic relays and the main visual extrageniculate thalamic nucleus in rodents and primates. Although primate studies report the pulvinar is engaged under attentional demands, there are open questions about the detailed role of the pulvinar in visuospatial attention. The pulvinar provides the primary thalamic input to the posterior parietal cortex (PPC).

Single neuron activity and theta modulation in the posterior parietal cortex in a visuospatial attention task.

The posterior parietal cortex (PPC) is implicated in directing and maintaining visual attention to locations in space. We hypothesized that the PPC also engages other cognitive processes in the transformation of behaviorally relevant visual inputs into appropriate actions, for example, monitoring of multiple locations, selection of responses to locations in space, and monitoring the outcome of response selections. We recorded single cells and local field potentials in the rat PPC during performance on a novel visuospatial attention (VSA) task that requires visually monitoring locations in space in order to make appropriate stimulus-guided locomotor responses.

Automated visual cognitive tasks for recording neural activity using a floor projection maze.

Neuropsychological tasks used in primates to investigate mechanisms of learning and memory are typically visually guided cognitive tasks. We have developed visual cognitive tasks for rats using the Floor Projection Maze(1,2) that are optimized for visual abilities of rats permitting stronger comparisons of experimental findings with other species. In order to investigate neural correlates of learning and memory, we have integrated electrophysiological recordings into fully automated cognitive tasks on the Floor Projection Maze(1,2).

Interactions of the dorsal hippocampus, medial prefrontal cortex and nucleus accumbens in formation of fear memory: difference in inhibitory avoidance learning and contextual fear conditioning.

Learning active or reactive responses to fear involves different brain circuitry. This study examined how the nuclus accumbens (NAc), dorsal hippocampus (DH) and medial prefrontal cortex (mPFC) may interact in memory processing for these two kinds of responses. Male Wistar rats with cannulae implanted in these areas were trained on a contextual fear conditioning or inhibitory avoidance task that respectively engaged a reactive or active response to fear in the test.