Synaptic modulation of glutamate in striatum of the YAC128 mouse model of Huntington disease.

Background: Altered balance between striatal direct and indirect pathways contributes to early motor, cognitive and psychiatric symptoms in Huntington disease (HD). While degeneration of striatal D2-type dopamine receptor (D2)-expressing indirect pathway medium spiny neurons (iMSNs) occurs prior to that of D1-type dopamine receptor (D1)-expressing direct pathway neurons, altered corticostriatal synaptic function precedes degeneration. D2-mediated signaling on iMSNs reduces their excitability and promotes endocannabinoid (eCB) synthesis, suppressing glutamate release from cortical afferents.

An optical brain-machine interface reveals a causal role of posterior parietal cortex in goal-directed navigation.

Cortical circuits contain diverse sensory, motor, and cognitive signals, and form densely recurrent networks. This creates challenges for identifying causal relationships between neural populations and behavior. We developed a calcium imaging-based brain-machine interface (BMI) to study the role of posterior parietal cortex (PPC) in controlling navigation in virtual reality.

Hormonal Contraceptive Use and Physical Performance, Body Composition, and Musculoskeletal Injuries during Military Training.

Purpose: To investigate associations between hormonal contraceptive use and physical performance, body composition, and musculoskeletal injuries in basic military training.Methods: Female British Army recruits (n = 450) were grouped as non-users (n = 182), combined oral contraceptive users (COCP; n = 184), or progestin-only users (POC; n = 144). Physical performance (2.