A possible mechanism of temporal lobe epilepsy is insufficient inhibition of hippocampal dentate granule cells. Precipitating injuries that kill interneurons in the dentate gyrus might result in fewer inhibitory synapses with granule cells. To test this hypothesis, previous studies evaluated numbers or densities of interneurons, γ-amino butyric acid (GABA)ergic boutons, and inhibitory synapses in tissue from human patients with temporal lobe epilepsy and rodent models. However, those studies have limitations. Some of those limitations can be addressed by a large animal model. Sea lions ( Zalophus californianus ) can develop temporal lobe epilepsy naturally. Like humans, epileptic sea lions exhibit bilateral or unilateral hippocampal sclerosis (neuron loss) with granule cell vulnerability, but sea lions permit optimal tissue preservation and sampling, and good control subjects. To label interneuron cell bodies and GABAergic synaptic boutons, sea lion hippocampal tissue from both sexes was processed with imm...

The current treatment for drug-resistant epilepsy is surgical intervention, which relies on accurate identification of the seizure onset zone (SOZ) using intracranial electroencephalography (iEEG) data. iEEG analysis with computational epileptogenic zone identification algorithms (CEZIAs) is a promising step toward better SOZ localization and surgical outcomes. A key step in validation and adoption of CEZIAs is to allow for widespread shared development and validation of code and data. To achieve this, we developed an ecosystem of seizure localization methods that includes a straightforward analysis pipeline, standardized data formatting and storage, and completely documented and open-source code. The TableContainer package provides standardized storage of tabular data and serves as a foundational data structure for the ecosystem. Building on this, the Epoch package enables cropping, resampling, and visualization of iEEG data and provides publicly downloadable datasets for reproducibility. The public iEEG ...

Social media (SM) use is typically regarded as a technological tool which might negatively impact physical fitness and cognitive function, especially in critical developmental stages. In this opinion paper, we argue that specific forms of SM content might be beneficial for promoting motor skill acquisition and function. Furthermore, we suggest that SM use might be a promising innovative tool for educational purposes in optimizing skills not only in sports but also in academia. As a prerequisite, future research is needed to clarify the optimal type of content, its use, and how these parameters are affected by age. Therefore, longitudinal studies across the lifespan are necessary for a thorough understanding of the potential beneficial effects of SM use. The use of social media (SM) has rapidly accelerated due to technological progress and the release of the first SM platforms such as Facebook in the early 2000s. During the Covid-19 pandemic, lockdowns and social distancing acted as catalysts, contributing...

Science education is traditionally framed as a driver of scientific literacy and economic growth. However, emerging evidence suggests that it may also function as a contributor to public health by shaping brain health across the lifespan. In this invited commentary, I synthesize findings from human and animal studies to examine how enriched, inquiry-based educational experiences intersect with neural processes underlying cognitive development, stress regulation, executive function, and social-emotional well-being. This synthesis is guided by the principle of cognitive compassion, which emphasizes the design of learning environments that support both cognitive and emotional needs. Research on neuroplasticity, stress biology, and motivation indicates that learning contexts characterized by curiosity, emotional safety, and active engagement are associated with adaptive neural function and long-term cognitive resilience. Drawing on empirical literature and illustrative translational observations from education...

Repeated restraint stress (RRS) in rats impairs cognitive flexibility, particularly when faced with additional mild acute stress (AS). We tested the hypothesis that this impairment is associated with altered dopaminergic activity in the dorsal striatum (DS) driven by corticotropin-releasing-factor receptor type 1 (CRFR1) in the substantia nigra pars compacta (SNpc). Sixty-two male rats received RRS or handling for 14 d, before training on a two-action, two-outcome instrumental conditioning task. Initial learning was assessed using an outcome devaluation test. Cognitive flexibility was assessed by reversing the outcome identities and a second outcome devaluation test, with half the rats in each group receiving AS before reversal training. Dopamine and metabolites were quantified in the DS, and CRFR1 mRNA was quantified in the SNpc. In Experiment 2, SNpc CRFR1 was pharmacologically blocked unilaterally before AS and reversal training in 32 male and 32 female rats. Increased dopaminergic activity in the DS an...

Accurate time estimation is essential for optimizing our perception and actions. Previous neuroimaging and transcranial magnetic stimulation (TMS) studies have suggested that the right inferior parietal lobule (IPL) and supplementary motor area (SMA) are involved in time perception. However, it remains inconclusive whether the activity in these regions is crucial for time perception, partly due to the possible spread of TMS effects across anatomically connected brain regions. Such a remote effect is less likely to happen with transcranial static magnetic stimulation (tSMS), as the static magnetic field is expected to modulate the firing threshold of neurons rather than directly triggering an action potential. In this study, we aimed to determine the causal relevance of local activities in the right IPL and the SMA for temporal processing using tSMS. Forty-eight human volunteers (26 males and 22 females) participated in the study. We measured duration discrimination thresholds, along with orientation discri...

Consumption varies across the stages (metestrus, diestrus, proestrus, estrus) of a rat's estrous cycle, changing in ways that might be expected to reflect, in part, a direct impact of hormones on taste palatability. Evidence regarding this hypothesis has been mixed, however, and critical within-subject experiments comparing consumption of multiple tastes with distinct valences across all estrous phases have been few. Here, we assayed female rats' licking of palatable (saccharin, sucrose, NaCl) and aversive (quinine-HCl, citric acid) tastes in brief-access trials, while tracking their estrous cycles through vaginal cytology. We observed sucrose palatability to be high at metestrus, the same phase at which the palatability of the aversive citric acid was low. These patterns were consistent across tastes of similar palatability, despite vast differences between the substances' receptor mechanisms and central impacts. Together, these results reveal a general (i.e., independent of particular tastant identity) m...

Harmonicity is a property of complex sounds such as vocalizations or music, but it remains unclear how harmonicity is processed in the auditory cortex (ACtx). Subregions of ACtx are thought to process harmonic stimuli differently. Selective responses to sound features in ACtx emerge hierarchically from primary ACtx (A1) L4 and secondary ACtx (A2) layer (L)2/3, which is believed to be the most responsive to harmonic sounds. Since harmonic stacks can range from 2 to >10 components, being more similar to naturalistic vocalizations, harmonic sensitivity might also arise hierarchically across layers and areas. We studied responses to harmonic stacks of 2–10 frequencies across A1 L4, A1 L2/3, and A2 L2/3 in adult male and female mice using in vivo two-photon microscopy. We found harmonic-sensitive neurons (HNs) responding only to harmonic stacks but not to individual frequencies in all areas at similar proportions. HNs showed highly nonlinear spectral integration of harmonic frequencies that decreased as the har...

Bridging integrator 1 ( BIN1 ) is one of the strongest genetic risk factors for Alzheimer’s disease (AD), yet its function in the brain and role in AD remain unclear. Neuronal BIN1 isoform levels are decreased in AD, and recent data show an important role of BIN1 in inhibitory neurons. Inhibitory neurons are key regulators of cognition and network excitability, with parvalbumin-expressing (PV) neurons as the most abundant subtype. We tested the hypothesis that loss of BIN1 from PV neurons contributes to AD-related cognitive dysfunction and network hyperexcitability. We generated a cell type–specific conditional knock-out mouse line, Bin1- pvKO, and examined mice of both sexes. These mice showed few behavioral differences when assessed with traditional or machine learning–based behavioral tests, with only a slight reduction in exploratory behavior in aged cohorts. Bin1- pvKO mice showed no significant differences in network excitability on measures of induced seizure susceptibility and spiking on cortical e...

Sparse labeling techniques are essential for morphological analysis of the central nervous system. Various sophisticated strategies have been developed, but conventional methods, such as Golgi–Cox staining and biocytin injection, remain widely used. Recent advances in adeno-associated virus (AAV) technology have enabled sparse neuronal labeling in rodents, either through postnatal AAV injection or by coinjecting a dilute Cre recombinase-expressing driver with a Cre-dependent amplifier. However, postnatal AAV injection requires prior preparation, and Cre-dependent systems are incompatible with Cre-expressing or floxed genetic backgrounds. Here, we present a Cre-orthogonal AAV–based sparse labeling method that utilizes Supernova technology in male and female mice. We employed Flpe recombinase to achieve Cre-independent labeling. A retro-orbital injection of PHP.eB AAVs failed to label neurons, whereas local injection enabled the bright and sparse labeling of multiple neuronal types, including cerebellar neur...