Biology subjects

Madar, A.

Publications and source records attributed to Madar, A..

6 recordsLinked to original sources

bioRxiv2026

Musical training-induced plasticity reflects melodic rather than instrumental expertise

Musical training produces behavioral gains that extend beyond the practiced context. Yet, it is unclear whether such generalization is accompanied by broadly transferable neural changes or whether training-induced plasticity remains tied to the specific features of the learned material. In this study, 80 musically naive adults completed four piano-training sessions and underwent functional MRI before and after training. Twenty untrained participants served as passive controls. Participants performed a passive listening task in which they listened to the trained melody (Fur Elise) and an untrained melody (Ode to Joy), each played on a trained musical instrument (piano) and an untrained musical instrument (saxophone). Following training, participants demonstrated improved accuracy and rhythmic performance when playing an unfamiliar melody, indicating behavioral generalization. Training-induced neural changes, however, were predominantly associated with the learned melodic content. Listening to Fur Elise elicited increased activity in the intraparietal and supplementary motor cortex and in the cerebellum, as well as decreased activity in the superior temporal cortex. Consistently, pre- and post-training scans were most accurately classified based on brain activity to Fur Elise played on piano or saxophone, rather than brain response to Ode to Joy, suggesting that neural reorganization was driven more strongly by the practiced melody than by the trained instrumental timbre. Training also enhanced the neural separability of both melodic and instrumental information. Critically, pre-training responses to Fur Elise played on the piano predicted subsequent playing accuracy, whereas pre-training sensitivity to instrumental timbre predicted rhythmic performance in a novel melodic context. Together, these findings suggest that while acquired musical skills behaviorally transfer to novel material, practice-induced functional plasticity remains predominantly melody-specific. We conclude that musical skill acquisition reflects complementary contributions of pre-existing neural characteristics and learning-induced plasticity, with baseline auditory representations potentially supporting successful behavioral transfer.

neuroscience↗

bioRxiv2026

Altering facial preferences with context

Facial features are known to play a key role in how we judge a persons traits. However, in many scenarios people do not evaluate a person in isolation but are required to compare and choose between multiple candidates. Yet, the principles that govern these decisions remain unknown. In economic literature, decisions are known to be influenced by the context of available options, but it is unclear to what extent these principles apply to social decisions about naturalistic stimuli such as human faces. Here, we bridged between these two fields of research - face evaluations and economic decisions - to investigate whether facial preferences can be systematically shifted by context, exhibiting a well-known choice context effect, the "decoy effect". We asked participants to choose the person they think is more trustworthy from either a set of two ("target" and "competitor") or three faces (including a "decoy"). Based on economic theory, we carefully selected face sets using their trustworthiness rankings and perceptual similarity, and tested them across several exploratory samples (n=100-400) and one large, preregistered experiment (n=1099). We found that adding a decoy face to the choice set increased participants choices of the target option by up to 7%, while the decoy face was rarely selected, consistent with a typical decoy effect. These results provide direct evidence that social judgements are affected by the same context-dependent principles known from economic choices, and that the decoy effect can be generalized to complex naturalistic stimuli such as human faces, relevant to various real-world applications. Significance statementPeople often rely on facial judgements when choosing between candidates, like politicians or potential partners. These judgments are typically made in comparison to available alternatives rather than in isolation. In economic literature, decisions are known to depend on the context of alternatives, but it remains unclear whether social evaluations follow the same principles. Here, tested whether the "decoy effect", a well-known choice context effect, applies to social judgments. Participants were asked to choose the more trustworthy individual from either two (decoy-absent) or three faces (decoy-present). Adding a decoy face increased selection of the target face by up to 7%, while the decoy itself was rarely chosen, showing that social judgments are governed by the same context-dependent principles as economic choices.

neuroscience↗

bioRxiv2025

Latent dimensions in neural representations predict choice context effects

Choices are affected by the context of available alternatives, a phenomenon termed choice context effects. Current models of context effects require options to be described by two explicit numerical attributes. However, decision-makers might represent these options by additional latent attributes, which are hard to define a-priori. We propose to use participants neural representations to access the full attribute set they consider and predict context effects without modelling any explicit attributes. We first estimated the context effects elicited by lotteries using a behavioral sample. Then we recruited two fMRI samples with preregistered design to estimate the neural representations of each lottery without the context of choice. We predicted the context effects using only the similarity in neural representations between the individual lotteries, improving both out-of-sample and in-sample predictions compared to traditional methods. These neural representations encoded a mixture of explicit and latent attributes, previously inaccessible to researchers using only behavioral methods.

neuroscience↗

bioRxiv2022

The trembling hand unraveled: the motor dynamics and neural sources of choice inconsistency

Extensive evidence shows that humans are inconsistent with their choices. Yet, the neural mechanism underlying this type of choices remains unknown. Here, we aim to show that inconsistent choice is tied to the valuation process, but can also arise from motor errors during task execution. We report the results from three behavioral and neuroimaging studies. Subjects completed a risky-choice task to test their inconsistency levels, followed by two novel tasks, explicitly designed to examine motor output. We recorded mouse trajectories during task execution and designed 34 features to analyze motor dynamics in an exploratory manner. We show that motor dynamics predict inconsistency levels, even when motor output was absent any valuation elements. In the neuroimaging study, we show that inconsistency is associated with value brain circuits, but at the same time, is also related to activity in motor circuits. These findings suggest that (at least) two neural sources of noise contribute to inconsistent choice behavior.

neuroscience↗

bioRxiv2019

Release of stem cells from quiescence reveals multiple gliogenic domains in the adult brain

Quiescent neural stem cells (NSCs) in the adult ventricular-subventricular zone (V-SVZ) have a regional identity and undergo activation to generate neurons. The domains for gliogenesis are less explored. Here we show that Platelet-Derived Growth Factor Receptor beta (PDGFR{beta}) is expressed by adult V-SVZ NSCs that generate olfactory bulb interneurons and glia with slow baseline kinetics. Selective deletion of PDGFR{beta} in adult V-SVZ NSCs leads to their release from quiescence uncovering multiple domains in the septal wall for oligodendrocyte and astrocyte formation. Unexpectedly, we identify a novel intraventricular oligodendrocyte progenitor inside the brain ventricles. Together our findings reveal different NSC spatial domains for gliogenesis in the adult V-SVZ that are largely quiescent under homeostasis and may have key functions for brain plasticity.

neuroscience↗

bioRxiv2018

Leveraging chromatin accessibility for transcriptional regulatory network inference in T Helper 17 Cells

Transcriptional regulatory networks (TRNs) provide insight into cellular behavior by describing interactions between transcription factors (TFs) and their gene targets. The Assay for Transposase Accessible Chromatin (ATAC)-seq, coupled with transcription-factor motif analysis, provides indirect evidence of chromatin binding for hundreds of TFs genome-wide. Here, we propose methods for TRN inference in a mammalian setting, using ATAC-seq data to influence gene expression modeling. We rigorously test our methods in the context of T Helper Cell Type 17 (Th17) differentiation, generating new ATAC-seq data to complement existing Th17 genomic resources (plentiful gene expression data, TF knock-outs and ChIP-seq experiments). In this resource-rich mammalian setting, our extensive benchmarking provides quantitative, genome-scale evaluation of TRN inference combining ATAC-seq and RNA-seq data. We refine and extend our previous Th17 TRN, using our new TRN inference methods to integrate all Th17 data (gene expression, ATAC-seq, TF KO, ChIP-seq). We highlight new roles for individual TFs and groups of TFs (\"TF-TF modules\") in Th17 gene regulation. Given the popularity of ATAC-seq, which provides high-resolution with low sample input requirements, we anticipate that application of our methods will improve TRN inference in new mammalian systems, especially in vivo, for cells directly from humans and animal models.

systems biology↗