Hibernating animals can show neuroplasticity throughout the hibernation season. In ground squirrels, decreased dendritic arborization in the hippocampus, somatosensory cortex, and thalamus during deep hibernation (“torpor”) suggests that this neuroplasticity is a brain-wide phenomenon. However, the degree to which neuroplasticity occurs in the visual system is not clear. While transient retinal changes have been reported during torpor, neuroplasticity beyond the retina remains unknown. Here, we characterized hibernation-related neuroplasticity in the primary visual cortex (V1), the first cortical area to receive visual information, in the thirteen-lined ground squirrel (Ictidomys tridecemlineatus). We compared neuronal morphology in Golgi-stained samples from male and female hibernating or non-hibernating squirrels. For the hibernating squirrels, brain tissue was sampled during two different epochs: torpor and inter-torpor arousal. Dendritic arborization decreased during torpor in V1 layer 2/3 pyramidal neurons, manifesting as decreases in dendritic length, number, and complexity. These changes fully reversed during inter-torpor arousal, indicating that on average dendritic arbors grew by 0.75 mm (65%) over ∼1.5 hours. No morphological differences between hibernating and non-hibernating squirrels were apparent when compared 6 months after the hibernation season. We also found no neuroplastic changes in V1 layer 4 spiny stellate neurons, unlike in this cell type the somatosensory cortex. Together, this revealed, for the first time, hibernation-related neuroplasticity in V1 in support of a brain-wide mechanism but with area-specific differences. The speed and magnitude of this naturally occurring neuroplasticity could make ground squirrel V1 a powerful translational model system for conditions requiring neuroplasticity, such as recovery from stroke.

Significance Statement This study is the first demonstration of pronounced hibernation-related neuroplasticity in the primary visual cortex of ground squirrels. Layer 2/3 pyramidal neurons in the primary visual cortex (V1) reduced arborization during torpor. Within 1.5 hours after arousal from torpor, the arborization reversed to non-hibernation levels. The extent and speed of this naturally occurring neuroplasticity could make the relatively well-understood V1 of ground squirrels a powerful translational model system. Complementing insights on neuroplasticity in V1 during development, it has the potential to be leveraged for the study of treatment mechanisms and conditions requiring neuroplasticity, ranging from neurodegeneration to recovery after stroke.

Scientists at the Max Planck Florida Institute for Neuroscience (MPFI), in collaboration with ZEISS and MetaCell, have developed a powerful new imaging pipeline called Neuroplex. As described in a paper published in eLife, the technique allows simultaneous monitoring of the activity of up to nine distinct neuronal populations in freely moving mice, dramatically accelerating the pace of scientific exploration into how the brain controls behavior.

For years, neuroscientists linking brain activity to behavior have faced a fundamental limitation: Miniscopes, the tiny head-mounted microscopes used to observe neural activity in behaving animals, could capture neural activity, but couldn’t reliably distinguish more than two different types of brain cells at a time.

“To understand the brain, we need to link patterns of activity in specific neurons to behavior,” stated lead author Dr. Mary Phillips. “We can readily use labels to color-code different populations of neurons, but when using miniscopes to correlate neural activity to behavior, we couldn’t distinguish more than two of these populations. This made it difficult to compare the activity across multiple cell types and circuits to understand how specific circuits regulate behavior.”

Communication begins long before children learn to speak. Researchers at National Yang Ming Chiao Tung University (NYCU) in Taiwan have now uncovered how early brain activity helps build developing communication circuits via regulating FOXP2/Foxp2, a gene linked to human speech and communication disorders.

Published in EMBO Reports, the study presents an integrated framework linking neural activity, vocal circuit development, and activity-dependent regulation of Foxp2 in early life. The researchers studied neonatal mice, which emit ultrasonic vocalizations when separated from their mothers. These vocalizations are widely used to study early social communication and neurodevelopmental disorders.

Using advanced activity tagging, live neural recording, and circuit manipulation techniques, the NYCU team identified a previously underappreciated communication circuit linking the ventromedial prefrontal cortex (vmPFC) and the striatum.

A new technology called LinCx allows scientists to create custom electrical connections between neurons with high precision. Researchers say it may help treat disorders caused by damaged brain circuits. Damage to brain circuits plays a major role in many neurological disorders. Researchers at Duk