Over the past ten years, an in situ chemical synthesis approach to biological systems has emerged, in which functional materials are assembled within tissues such as the brain – either constructed throughout the intact tissue (hydrogel-tissue chemistry/HTC), or genetically targeted to cell types (genetically-targeted chemical assembly/GTCA). Resulting hybrid materials are endowed with diverse capabilities, including anchoring and labeling of RNA and protein, in situ sequencing, transparency, reversible size changes, and electrical insulation or conduction.

Speech in everyday life is often masked by background noise, making comprehension effortful. Characterizing brain activity patterns when individuals listen to masked speech can help clarify the mechanisms underlying such effort. In the current study, we used functional magnetic resonance imaging (fMRI) in humans of either sex to investigate how neural signatures of story listening change in the presence of masking noise. We show that, as speech masking increases, spatial and temporal activation patterns in auditory regions become more idiosyncratic to each listener. In contrast, spatial activity patterns in brain networks linked to effort (e.g. cinguloopercular network) are more similar across listeners when speech is highly masked and less intelligible, suggesting shared neural processes. Moreover, at times during stories when one meaningful event ended and another began, neural activation increased in frontal, parietal, and medial cortices. This event-boundary response appeared little affected by backgro...

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Felix Schneider discusses his paper, “Neuron Replating, a Powerful and Versatile Approach to Study Early Aspects of Neuron Differentiation,” published in Vol. 8, Issue 3 of eNeuro, with Editor-in-Chief Christophe Bernard. 

Neuronline is a benefit of SfN membership. Renew your membership now to make sure you don’t lose access.

Neuronline is a benefit of SfN membership. Renew your membership now to make sure you don’t lose access.

Felix Schneider discusses his paper, “Neuron Replating, a Powerful and Versatile Approach to Study Early Aspects of Neuron Differentiation,” published in Vol. 8, Issue 3 of eNeuro, with Editor-in-Chief Christophe Bernard. 

Investigations into the neural basis of behavior frequently employ calcium imaging to measure neuronal activity. Across studies, however, seemingly reasonable but highly diverse methodological choices are typically made to assess the selectivity of individual neurons to task states. Here, we examine systematically the effect of parameter choices, along the pipeline from data acquisition through statistical testing, on the inferred encoding preferences of individual neurons. We use, as an experimental testbed, calcium imaging in the medial prefrontal cortex of freely behaving mice engaged in a classic exploration-avoidance task with animal-controlled state transitions, namely, navigation in the elevated zero maze. We report that most of the key parameters in the pipeline substantially impact the inferred selectivity of neurons and do so in distinct ways. Using novel accuracy and robustness metrics, we directly compare the quality of inference across combinations of parameter levels and discover an optimal c...

Repetitive mild traumatic brain injury (rmTBI) is a major contributor to long-term neurological dysfunction, yet many preclinical models lack precise control and quantification of biomechanical forces across impacts. We developed a reproducible, closed-skull mouse model of rmTBI using a custom-built weight–drop apparatus featuring a solenoid-based rebound arrest system, integrated high-speed videography, and accelerometry to track head kinematics during impact. Adult male and female mice received either a single impact or nine daily impacts. Linear and angular acceleration data were analyzed alongside behavioral and histological outcomes. Our apparatus delivered consistent impact and velocity forces with minimal intersubject variability. Additionally, the animals experienced consistent linear and angular acceleration as measured using high-speed video capture. These impacts did not cause skull fracture or acute vascular hemorrhage, but impacted animals had increased return of righting reflex time, consiste...

The growing therapeutic promise of repeated, low-dose ketamine treatment across various psychopathologies—including depression and drug addiction—warrants clarity on its potential addictive properties and their associated mechanisms in both sexes. Accordingly, the present work examined the effects of intermittent low-dose ketamine in male and female rats on behavioral sensitization to the locomotor-activating effects of ketamine, as well as associated molecular profiles in dopamine D1- and D2-receptor-expressing medium spiny neurons (D1- and D2-MSNs) of the nucleus accumbens (NAc). Following intra-NAc infusion of a Cre-inducible RiboTag virus, locomotor activity was measured in adult Drd1a-iCre and Drd2-iCre male and female rats in either diestrus or proestrus following repeated administration of ketamine (0, 10, or 20 mg/kg, i.p.) to evaluate the development of locomotor sensitization. Female—but not male—rats developed sensitization to the locomotor-activating effects of ketamine, occurring more rapidly ...