Transgenic mice provide unprecedented access to manipulate and visualize neural circuits; however, those on a C57BL/6 background develop progressive hearing loss, significantly confounding systems-level and behavioral analysis. While outbreeding can limit hearing loss, it introduces strain variability and complicates the generation of complex genotypes. Here, we propose an approach to preserve hearing by crossing transgenic mice with congenic B6.CAST- Cdh23Ahl + mice, which maintain low-threshold hearing into adulthood. Widefield and two-photon imaging of the auditory cortex revealed that 2.5-month-old C57BL/6 mice exhibit elevated thresholds to high-frequency tones and widespread cortical reorganization, with most neurons responding best to lower frequencies. In contrast, Ahl+ C57BL/6 mice exhibited robust neural responses across tested frequencies and sound levels (4–64 kHz, 30–90 dB SPL) and retained low thresholds into adulthood. Our approach offers a cost-effective solution for generating complex geno...

Growth hormone (GH) is a neuromodulator that binds to receptors in the hippocampus and alters synaptic plasticity. A decline in GH levels is associated with normal aging, stress, and disease, and the mechanisms proposed involve the hippocampal circuit plasticity. To see how GH affects the hippocampal neural code, we recorded single neurons in the CA1 region of male Long–Evans rats with locally altered GH levels. Rats received injections of adeno-associated viruses into the hippocampus to make the cells overexpress either GH or an antagonizing mutated GH (aGH). Place cells were recorded in both familiar and novel environments to allow the assessment of pattern separation in the neural representations termed remapping. All the animals showed intact and stable place fields in the familiar environment. In the novel environment, aGH transfection increased the average firing rate, peak rate, and information density of the CA1 place fields. The tendency of global remapping increased in the GH animals compared wit...

Axons in the mammalian brain show significant diversity in myelination motifs, displaying spatial heterogeneity in sheathing along individual axons and across brain regions. However, its impact on neural signaling and susceptibility to injury remains poorly understood. To address this, we leveraged cable theory and developed model axons replicating the myelin sheath distributions observed experimentally in different regions of the mouse central nervous system. We examined how the spatial arrangement of myelin affects propagation and predisposition to conduction failure in axons with cortical versus callosal myelination motifs. Our results indicate that regional differences in myelination significantly influence conduction timing and signaling reliability. Sensitivity of action potential propagation to the specific positioning, lengths, and ordering of myelinated and exposed segments reveals non-linear and path-dependent conduction. Furthermore, myelination motifs impact signaling vulnerability to demyelina...

Extended performance of cognitively demanding tasks induces cognitive fatigue manifested with an overall deterioration of behavioral performance. In particular, long practice with tasks requiring impulse control is typically followed by a decrease in self-control efficiency, leading to performance instability. Here, we show that this is due to changes in activation modalities of key task-related areas occurring if these areas previously underwent intensive use. We investigated in 25 healthy adults the effects of extended practice with high cognitive demand (HCD) tasks on a Go-No Go task and the underlying electroencephalographic (EEG) activity. We compared these effects with those induced by practice with similar, but low cognitive demand (LCD) tasks. HCD tasks were followed by an increase in response inhibition failures. These were correlated with the appearance of a distinct neural signature on fast response trials, characterized by lower levels of beta ([13–30] Hz) EEG activity in the prestimulus period...

Hearing impairment (HI) disrupts social interaction by hindering the ability to follow conversations in noisy environments. While hearing aids (HAs) with noise reduction (NR) partially address this, the “cocktail-party problem” persists, where individuals struggle to attend to specific voices amidst background noise. This study investigated how NR and an advanced signal processing method for compensating for nonlinearities in Electroencephalography (EEG) signals can improve neural speech processing in HI listeners. Participants wore HAs with NR, either activated or deactivated, while focusing on target speech amidst competing masker speech and background noise. Analysis focused on temporal response functions to assess neural tracking of relevant target and masker speech. Results revealed enhanced neural responses (N1 and P2) to target speech, particularly in frontal and central scalp regions, when NR was activated. Additionally, a novel method compensated for nonlinearities in EEG data, leading to improved...

Breathing is a complex neuromuscular process vital to sustain life. In pre-clinical animal models, the study of respiratory motor control is primarily accomplished through neurophysiologic recordings and functional measurements of respiratory output. Neurophysiologic recordings that target neural or muscular output via direct nerve recordings or respiratory muscle electromyography (EMG) are commonly collected during anesthetized conditions. While offering tight control of experimental preparations, the use of anesthesia results in respiratory depression, may impact cardiovascular control, eliminates the potential to record volitional non-ventilatory behaviors, and can limit translation. Since the diaphragm is a unique muscle which is rhythmically active and difficult to access, placing diaphragm EMGs to collect chronic recordings in awake animals is technically challenging. Here, we describe methods for fabricating and implanting indwelling diaphragm EMG electrodes to enable recordings from awake rodents f...

The amygdala is believed to make invaluable contributions to visual emotion processing. Yet how this subcortical body contributes to emotion perception across time is contended. Here, we measured differences in the perceptual processing of emotional stimuli after unilateral temporal lobe and amygdala resection (TLR) in humans, using EEG. Through mass univariate analysis of brain activity, we compared responses to fearful and neutral faces (left TLR N = 8, right TLR N = 8, control N = 8), and fearful and neutral bodies (left TLR N = 9, right TLR N = 9, control N = 9). We found that TLR impaired the early-stage perceptual processing of emotional stimuli seen in the control group. Indeed, in controls a heightened responses to fearful faces was found in the 140-170 ms time window, over temporo-parietal electrodes. This effect was also present in the left TLR group but disappeared in the right TLR group. For emotional bodies, brain activity was differentially sensitive to fearful stimuli at 90-120 ms in the con...

This webinar will provide scientists with information about how to develop precise and effective significance statements to accompany their work. These statements are increasingly being used by agencies reviewing science for funding opportunities, editorial reviewers for publication in scientific journals, and the media. The goal of this webinar is to inform the neuroscience community about the benefits of creating a significance statement in a way that peaks the interest of others in the field, as well as laypersons, which can lead to opportunities for published research and/or funding.

As my research in graduate school has developed, it has become clear how important federal and state funding is to my future.

Public support of science can be instrumental in influencing congressional support of research funding. While public support for science is strong, few Americans understand our nation’s scientific enterprise.