A chemogenetic tool was applied to macaque monkeys, and activity in the subthalamic nucleus, a part of the basal ganglia, was suppressed. During suppression, monkeys’ reaching movements became unstable, and involuntary movements were induced. In the output nucleus of the basal ganglia, the internal pallidum, neurons showed no firing rate change, but their spike train became variable. The subthalamic nucleus may stabilize neural activity in the basal ganglia for smooth movements.

Deep brain stimulation (DBS), applying electric stimulation to the subthalamic nucleus, can effectively treat advanced Parkinson’s disease. Both adaptive DBS (aDBS) driven by primary motor cortical activity and conventional constant DBS (cDBS) significantly decreased reaction and movement times in parkinsonian monkeys. The electric charge delivered with aDBS was lower than that with cDBS. aDBS is an effective therapeutic approach with lower electrical requirements.

Researchers from Osaka University discovered a small group of brain cells in the claustrum of mice that bidirectionally controls stress-induced anxiety behaviors. Deactivation of these cells made mice more resilient against chronic stress. These findings could be the key to understanding the cause of stress-related disorders.

Tau present in the extracellular fluids has a critical role in the pathogenesis of tauopathies. The authors describe that glymphatic clearance of extracellular tau impacts tau accumulation and neurodegeneration. The study implicates glymphatic system in the pathophysiology of tauopathies.

The researchers developed a Rosa26 knockin mouse that expresses a green calcium indicator (G-CaMP9a) with fast kinetics and a high signal-to-noise ratio. This reporter mouse allows for the investigation of neuronal activity in defined cell populations and will facilitate dissecting complex dynamics of neural networks in vivo.

The researchers have extended the applicability of tissue clearing techniques to EM. For this, they developed an ultrastructurally-preserved tissue clearing method, ScaleSF, and LM/EM dual labeling stable in the clearing protocol. Their imaging pipeline allows for deciphering brain-wide connectivity by simultaneous interrogation of the neural circuit structure and synaptic connectivity.