Models of experience-dependent neuroplasticity predict that the acquisition and extensive use of a new skill trigger a nonlinear trajectory of neurostructural modifications, where initial expansion of relevant brain areas subsequently (once the skill is acquired) gives way to volumetric renormalization. Such predictions also apply in the domain of language during learning and/or simultaneous management of two (or more) linguistic systems. In a sample of 69 young adult Russian–English bilinguals, we tested the hypothesis that individual differences in bilingual engagement nonlinearly correlate with normalized volume of the hippocampus—a key learning-related brain region particularly amenable to experience-dependent plasticity. Results revealed an inverted U-shape association between second language engagement and left hippocampal gray matter volume. The present results replicate and expand the findings from aging populations, showing a nonlinear pattern of structural hippocampal plastic

Regardless of discipline, quantitative literacy is a critical component of any scientist’s skill set. A recent push from the NINDS has focused on enhancing and maintaining this expertise in trainees to enhance scientific fluency and to combat the reproducibility crisis. T32-funded programs often include off-campus retreats, providing opportunities to integrate a quantitative literacy component, or thematic focus. Here we will discuss the lessons and considerations learned from organizing a retreat focused on quantitative aspects of diagnostics for spinal cord injury. Survey results regarding retreat events and workshops reveal elements that were perceived to be successful by attendees. Events developed with active learning that focused on collaborative problem-solving and cross-discipline quantitative measures were well received by trainees. On the other hand, lectures and panel discussions were found to be less effective in boosting long-lasting improvements in quantitative literacy.

The annual Society for Neuroscience (SfN) meeting is a bonanza of scientific achievement: famous keynote speakers, beautiful scientific results, and award ceremonies. This focus is exciting and invigorating but glosses over the many failures, mistakes, and rejections that typically lead to scientific success. Our goal has been to create a space within the annual SfN meeting for open conversation about scientific failure and, by doing so, increase transparency, resilience, and mental well-being within our community. In this article, we share the materials that we have used at SfN during the past 4 years (2021–2024) to promote discussions of scientific failure, including formal storytelling, individual and interactive games, and confessionals. For each activity, we provide the rationale and practical guidance regarding logistics and usage. We hope this will aid scientists interested in adapting the activities for their own communities or local events. We end with a call for scientific in

Rod and cone photoreceptor cells selectively contact different compartments of axon-bearing retinal horizontal cells in the mammalian retina. Cones synapse exclusively on the soma whereas rods synapse exclusively on a large axon terminal compartment. The possibility that rod signals can travel down the axon from terminal to soma has been proposed as a means of producing spectrally opponent interactions between rods and cones, but there is conflicting data about whether this actually occurs. The spectral overlap between rods and cones in mouse makes it difficult to stimulate rod and cone pigments separately. We therefore used optogenetic techniques to analyze photoreceptor inputs into horizontal somas by selectively expressing channelrhodopsin in rods and/or cones. Optogenetic stimulation of rods and cones both evoked large fast inward currents in horizontal cell somas. Cone-driven responses were abolished by eliminating synaptic release in a cone-specific knock-out of the exocytotic ca

Understanding the ability to self-evaluate decisions is an active area of research. This research has primarily focused on the neural correlates of self-evaluation during visual tasks and whether neural correlates before or after the primary decision contribute to self-reported confidence. This focus has been useful, yet the reliance on subjective confidence reports may confound our understanding of key everyday features of metacognitive self-evaluation: that decisions must be rapidly evaluated without explicit feedback and unfold in a multisensory world. These considerations led us to hypothesize that an automatic domain-general metacognitive signal may be shared between sensory modalities, which we tested in the present study with multivariate decoding of electroencephalographic (EEG) data. Participants ( N  = 21, 12 female) first performed a visual task with no request for self-evaluations of performance, prior to an auditory task that included rating decision confidence on each tri

Lifelong premature ejaculation (LPE) is associated with abnormal brain function, as evidenced by functional MRI (fMRI) studies. This study investigates the stability of brain network architectures in resting-state conditions following perturbation by erotic tasks in individuals with LPE. We assessed the resting-state fMRI in the task-free and task-modulated dataset in the 28 right-hand LPE and 17 age-matched normal controls (NCs). The dynamic functional connectome based on the phase-locking algorithm and ROI-wise gradient mapping was compared. The stability of dynamic functional gradient mapping was measure by linear mixed effects across the two datasets in the LPE and NCs. In both groups, the brain functional gradient exhibited a clear transition from unimodal to transmodal in the principal gradient. Additionally, there was a segregation of primary networks observed in the secondary gradient, either before or after the task. In LPE patients, we observed increased stability in the bila

The rodent brain contains 70,000,000+ neurons interconnected via complex axonal circuits with varying architectures. Neural pathologies are often associated with anatomical changes in these axonal projections and synaptic connections. Notably, axonal density variations of local and long-range projections increase or decrease as a function of the strengthening or weakening, respectively, of the information flow between brain regions. Traditionally, histological quantification of axonal inputs relied on assessing the fluorescence intensity in the brain region of interest. Despite yielding valuable insights, this conventional method is notably susceptible to background fluorescence, postacquisition adjustments, and inter-researcher variability. Additionally, it fails to account for nonuniform innervation across brain regions, thus overlooking critical data such as innervation percentages and axonal distribution patterns. In response to these challenges, we introduce AxoDen, an open-source

Lactate plays an important role in brain energy metabolism. It contributes to normal brain development and to neuroprotection in diabetic hypoglycemia, but its role in neonatal hypoglycemia is unclear. Moreover, lactate can work as a signaling substance via the lactate receptor HCAR1 (Hydroxycarboxylic acid receptor 1). Recent studies indicate that HCAR1 is protective in mouse models of neonatal hypoxic ischemia and has a role in metabolic regulation in glial cells during hypoglycemia. Here we have studied potential impacts of HCAR1 on axonal and myelin development in the cerebral cortex and corpus callosum of young (P21) wild-type (WT) mice and HCAR1 KO mice and in cortical organotypic brain slice cultures. The HCAR1 KO mice showed lower axonal area relative to WT in both cortex and corpus callosum. However, the myelin area was unaffected by HCAR1 KO. Using particle and colocalization analysis, we show that HCAR1 KO predominantly reduces axonal size in unmyelinated axons. Using an org