Highlighted Research Paper: [[M. Dusing, C. L. LaSarge, A. White, L. G. Jerow, C. Gross and S. C. Danzer, “Neurovascular Development in Pten and Tsc2 Mouse Mutants.”][2]][2] []: /lookup/doi/10.1523/ENEURO.0340-22.2023

The brain interprets sensory inputs to guide behavior, but behavior itself disrupts sensory inputs. Perceiving a coherent world while acting in it constitutes active perception. For example, saccadic eye movements displace visual images on the retina and yet the brain perceives visual stability. Because this percept of visual stability has been shown to be influenced by prior expectations, we tested the hypothesis that it is Bayesian. The key prediction was that priors would be used more as sensory uncertainty increases. Humans and rhesus macaques reported whether an image moved during saccades. We manipulated both prior expectations and levels of sensory uncertainty. All psychophysical data were compared with the predictions of Bayesian ideal observer models. We found that humans were Bayesian for continuous judgments. For categorical judgments, however, they were anti-Bayesian: they used their priors less with greater uncertainty. We studied this categorical result further in macaques. The animals’ judgm...

About one-third of individuals living with epilepsy have treatment-resistant seizures. Alternative therapeutic strategies are thus urgently needed. One potential novel treatment target is miRNA-induced silencing, which is differentially regulated in epilepsy. Inhibitors (antagomirs) of specific microRNAs (miRNAs) have shown therapeutic promise in preclinical epilepsy studies; however, these studies were mainly conducted in male rodent models, and research into miRNA regulation in females and by female hormones in epilepsy is scarce. This is problematic because female sex and the menstrual cycle can affect the disease course of epilepsy and may, therefore, also alter the efficacy of potential miRNA-targeted treatments. Here, we used the proconvulsant miRNA miR-324-5p and its target, the potassium channel Kv4.2, as an example to test how miRNA-induced silencing and the efficacy of antagomirs in epilepsy are altered in female mice. We showed that Kv4.2 protein is reduced after seizures in female mice similar ...

Previous diagnostic systems precluded the co-existence of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in one person; but, after many clinical reports, the diagnostic criteria were updated to allow their co-occurrence. Despite such a clinical change, the neurobiological bases underpinning the comorbidity remain poorly understood, and whether the ASD+ADHD condition is a simple overlap of the two disorders is unknown. Here, to answer this question, we compared the brain dynamics of high-functioning ASD+ADHD children with age-/sex-/IQ-matched pure ASD, pure ADHD, and typically developing (TD) children. Regarding autistic traits, the socio-communicational symptom of the ASD+ADHD children was explained by the same overstable brain dynamics as seen in pure ASD. In contrast, their ADHD-like traits were grounded on a unique neural mechanism that was unseen in pure ADHD: the core symptoms of pure ADHD were associated with the overly flexible whole-brain dynamics that were trigg...

After corticospinal tract damage, reticulospinal connections to motoneurons strengthen preferentially to flexor muscles. This could contribute to the disproportionately poor recovery of extensors often seen after spinal cord injury (SCI) and stroke. In this study, we paired electrical stimulation over the triceps muscle with auditory clicks, using a wearable device to deliver stimuli over a prolonged period of time. Healthy human volunteers wore the stimulation device for ∼6 h and a variety of electrophysiological assessments were used to measure changes in triceps motor output. In contrast to previous results in the biceps muscle, paired stimulation: (1) did not increase the StartReact effect; (2) did not decrease the suppression of responses to transcranial magnetic brain stimulation (TMS) following a loud sound; (3) did not enhance muscle responses elicited by a TMS coil oriented to induce anterior-posterior current. In a second study, chronic cervical SCI survivors wore the stimulation device for ∼4 h ...

Network plasticity in the medial perforant path (MPP) of adult (five to nine months) and aged (18–20 months) urethane-anesthetized male and female Sprague Dawley rats was characterized. Paired pulses probed recurrent networks before and after a moderate tetanic protocol. Adult females exhibited greater EPSP-spike coupling suggesting greater intrinsic excitability than adult males. Aged rats did not differ in EPSP-spike coupling but aged females had larger spikes at high currents than males. Paired pulses suggested lower GABA-B inhibition in females. Absolute population spike (PS) measures were larger post-tetani in female rats than male rats. Relative population spike increases were greatest in adult males relative to females and to aged males. EPSP slope potentiation was detected with normalization in some post-tetanic intervals for all groups except aged males. Tetani shortened spike latency across groups. Tetani-associated NMDA-mediated burst depolarizations were larger for the first two trains in each ...

Responding rapidly to visual stimuli is fundamental for many animals. For example, predatory birds and insects alike have amazing target detection abilities, with incredibly short neural and behavioral delays, enabling efficient prey capture. Similarly, looming objects need to be rapidly avoided to ensure immediate survival, as these could represent approaching predators. Male Eristalis tenax hoverflies are nonpredatory, highly territorial insects that perform high-speed pursuits of conspecifics and other territorial intruders. During the initial stages of the pursuit, the retinal projection of the target is very small, but this grows to a larger object before physical interaction. Supporting such behaviors, E. tenax and other insects have both target-tuned and loom-sensitive neurons in the optic lobes and the descending pathways. We here show that these visual stimuli are not necessarily encoded in parallel. Indeed, we describe a class of descending neurons that respond to small targets, to looming and to...

In the article “3D-Printed Pacifier-Shaped Mouthpiece for fMRI-Compatible Gustometers,” by David Munoz Tord, Géraldine Coppin, Eva R. Pool, Christophe Mermoud, Zoltan Pataky, David Sander, and Sylvain …

Neuroplasticity is maximal during development and declines in adulthood, especially for sensory cortices. On the other hand, the motor and prefrontal cortices retain plasticity throughout the lifespan. This difference has led to a modular view of plasticity in which different brain regions have their own plasticity mechanisms that do not depend or translate on others. Recent evidence shows that visual and motor plasticity share common neural mechanisms (e.g. GABAergic inhibition), indicating a possible link between these different forms of plasticity, however, the interaction between visual and motor plasticity has never been tested directly. Here we show that when visual and motor plasticity are elicited at the same time in adult humans, visual plasticity is impaired, while motor plasticity is spared. Moreover, simultaneous activation of working memory and visual plasticity also leads to impairment in visual plasticity. These unilateral interactions between visual, working memory and motor plasticity demo...

The balance between the degeneration and regeneration of damaged neurons depends on intrinsic and environmental variables. In nematodes, neuronal degeneration can be reversed by intestinal GABA and lactate-producing bacteria, or by hibernation driven by food deprivation. However, it is not known whether these neuroprotective interventions share common pathways to drive regenerative outcomes. Using a well-established neuronal degeneration model in the touch circuit of the bacterivore nematode Caenorhabditis elegans, we investigate the mechanistic commonalities between neuroprotection offered by the gut microbiota and hunger-induced diapause. Using transcriptomics approaches coupled to reverse genetics, we identify genes that are necessary for neuroprotection conferred by the microbiota. Some of these genes establish links between the microbiota and calcium homeostasis, diapause entry, and neuronal function and development. We find that extracellular calcium as well as mitochondrial MCU-1 and reticular SCA-1...