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 calcium sensor, synapto...

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 bilateral dorsal prefront...

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 plasticity in healthy young ...

Paying attention to a target talker in multitalker scenarios is associated with its more accurate neural tracking relative to competing non-target speech. This “neural bias” to target speech has largely been demonstrated in experimental setups where target and non-target speech are acoustically controlled and interchangeable. However, in real-life situations this is rarely the case. For example, listeners often look at the talker they are paying attention to while non-target speech is heard (but not seen) from peripheral locations. To enhance the ecological-relevance of attention research, here we studied whether neural bias toward target speech is observed in a spatially realistic audiovisual context and how this is affected by switching the identity of the target talker. Group-level results show robust neural bias toward target speech, an effect that persisted and generalized after switching the identity of the target talker. In line with previous studies, this supports the utility of the speech-tracking...

Dmrta2 (also designated Dmrt5) is a transcriptional regulator expressed in cortical progenitors in a caudomedialhigh/rostrolaterallow gradient with important roles at different steps of cortical development. Dmrta2 has been suggested to act in cortex development mainly by differential suppression of Pax6 and other homeobox transcription factors such as the ventral telencephalic regulator Gsx2 , which remains to be fully demonstrated. Here we have addressed the epistatic relation between Pax6 and Dmrta2 by comparing phenotypes in mutant embryos or embryos overexpressing both genes in various allelic combinations. We show that Dmrta2 cooperates with Pax6 in the maintenance of cortical identity in dorsal telencephalic progenitors and that it acts as a transcriptional repressor of Pax6 to control cortical patterning. Mechanistically, we show that in P19 cells, Dmrta2 acts as a DNA binding-dependent repressor on the Pax6 E60 enhancer and that a point mutation that affects its DNA binding properties identified i...

Savings refers to the gain in performance upon relearning. In sensorimotor adaptation, savings is tested by having participants adapt to perturbed feedback and, following a washout block during which the system resets to baseline, presenting the same perturbation again. While savings has been observed with these tasks, we have shown that the contribution from implicit adaptation, a process that uses errors to recalibrate the sensorimotor map, is attenuated upon relearning ( [Avraham et al., 2021][1]). Here, we test the hypothesis that this attenuation is due to interference arising from the different relationship between the movement and the feedback during washout. Removing the perturbation at the start of the washout block typically results in a salient error signal in the opposite direction to that observed during learning. We first replicated the finding that implicit adaptation is attenuated following a washout period that introduces salient opposite errors. When we eliminated feedback during washout,...

α-Synuclein is a synaptic protein that accumulates primarily in synucleinopathies and secondarily in certain lysosomal storage disorders. However, its physiological roles in health and disease are not fully understood. In part, this has been hampered by the inability to visualize α-synuclein and its cellular localization, due to the lack of specific antibodies and faithful reporters. Here, we used CRISPR/Cas9-based genome editing to generate human-induced pluripotent stem cell (iPSC) lines in which the α-synuclein ( SNCA ) gene has been tagged with the short HA peptide either at the N-terminus or C-terminus or with the fluorescent protein mCherry at the C-terminus of the protein. These diverse strategies revealed the C-terminus HA-tag as the best option. C-Terminus HA-tagged α-synuclein had unchanged protein expression and did not generate degradation by-products. Importantly, we show that following differentiation to neurons, the C-terminus HA-tagged iPSC line had unaffected electrophysiological propertie...

Glymphatic transport in rodents has primarily been studied using cisterna magna cannulation (CMC), a minimally invasive method for cerebrospinal fluid (CSF) tracers infusion. However, CMC is suboptimal due to the lack of bony structures to stabilize the cannula, leading to potential movement artifacts. Here, we present an alternative approach involving chronic cannulation of the lateral ventricles of mice for CSF tracer delivery. A direct comparison demonstrated that intraventricular cannulation (IVC) reproduces CMC results in vivo, including perivascular labeling of the middle cerebral artery, which was further confirmed by ex vivo analysis. IVC enables tracer infusion in awake mice, facilitating glymphatic transport studies in conjunction with behavioral assessments that were previously unattainable. Additionally, IVC supports repeated infusions in awake animals, offering the potential to reduce the number of experimental animals required. This study establishes IVC as a robust alternative for studying g...

The genetic role and specific effects of primary familial cerebral calcification (PFBC) are still unclear. We aim to analyze bibliometric features in studies related to PFBC, investigate variant detection rates in patients with brain calcifications, and examine the phenotypic characteristics of PFBC patients. A comprehensive search of studies on the genetic effects of PFBC up until December 31, 2024, was conducted across Web of Science, PubMed, Embase, and Scopus. A random-effects meta-analysis combined variant detection rates for genes SLC20A2 , PDGFRB , PDGFB , XPR1 , MYORG , JAM2 , CMPK2 , and NAA60 . Data on total calcification scores (TCS), age of onset, and the prevalence of various phenotypes in PFBC patients were also aggregated. Publication bias was assessed using Egger's linear regression, and a leave-one-out sensitivity analysis was performed. Of 1,267 records, 224 were included in the bibliometric analysis. Keywords “primary familial brain calcification” and “ SLC20A2 ” were most prominent. Eig...

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. Taken as a whole, the...