Biology subjects

Friedmann, R.

Publications and source records attributed to Friedmann, R..

3 recordsLinked to original sources

bioRxiv2026

Engaging Visual Media Shifts Taste-Related Neural Processing: An fMRI Study on Distracted Eating

BackgroundDistracted eating is prevalent in modern environments. While behavioral research consistently shows that distraction attenuates taste perception and increases food intake, the underlying neural mechanisms appear to be more complex. ObjectiveThis functional magnetic resonance imaging (fMRI) study investigated whether naturalistic distraction modulates gustatory processing via sensory suppression or reallocation of neural resources, as observed in more controlled cognitive load paradigms. MethodsThirty-eight healthy participants received sweet and umami taste stimuli of low and high concentration during fMRI scanning. Attentional state was manipulated using short food-related (low-distraction) versus film-related (high-distraction) video clips. After each video, participants rated perceived intensity and pleasantness. Group-level analyses included covariates for sex, body mass index (BMI), and hunger level. ResultsHigh distraction attenuated perceived intensity (p < 0.001, d = -0.28) and pleasantness (p < 0.01, d = -0.21), independent of taste category or concentration. No significant attenuation by distraction was observed in core gustatory regions (insula, orbitofrontal cortex). Instead, distraction increased activation in occipital, thalamic, and cerebellar regions, indicating a redistribution of processing resources toward visual and attentional systems. ConclusionDistraction reduced taste salience without lowering gustatory cortex activity, supporting resource-competition models rather than active sensory suppression. These results reinforce that the impact of distracted eating is behaviorally robust yet neurally subtle, highlighting the need for personalized stimuli and ecologically valid methods to capture real-world eating behavior. The study demonstrates that video-based paradigms work reliably in fMRI and capture how naturalistic distraction alters taste experience.

neuroscience↗

bioRxiv2025

Wavelet analysis of dual-fMRI-hyperscanning reveals cooperation and communication dependent effects on inter-brain neuronal coherence.

Hyperscanning has allowed neuroscience to expand investigations into neuronal activation during social interactions. Rather than analyzing how a single brain responds, we can compare interactions and even synchronization between multiple actors in varying situations. This technique is commonly employed using functional near infrared spectroscopy (fNIRS). Specifically, social cooperation and competition have been thoroughly investigated using this approach. While functional magnetic resonance imaging (fMRI)-based hyperscanning is becoming more prevalent, a link to this fNIRS-based foundation is missing. We here use a dual-fMRI-hyperscanning setup and an established task to investigate neuronal coherence during social cooperative and competitive tasks. Wavelet transform coherence (WTC) allows us to explore task-specific frequency bands of interest of non-stationary neuronal activation signals of paired participants (n=60). We show that cooperation, compared to a control task, increases inter-brain neuronal coherence in regions associated with social interaction and the theory of mind (ToM) network. Verbal communication prior to the task expands this coherence to different regions of this network, including middle and superior temporal gyrus. This spatial shift suggests additional implementations of the ToM network depending on the cooperation approach taken by the participants. Our findings both support and expand on results by previous fNIRS-based studies and show that WTC is an effective way to model fMRI-based neuronal synchronization; thereby closing the gap between two popular hyperscanning methodologies. Significance StatementWithin social neuroscience a strong basis exists for fNIRS-based hyperscanning. In the past years fMRI-based hyperscanning has increased in popularity, yet the basis for these projects seems to develop independent of the existing background. The current study aims to connect these previous findings to the possibilities offered by fMRI, allowing both fields to benefit from the others advantages when determining optimal research paradigms or analyses.

neuroscience↗

bioRxiv2023

New paradigms in actomyosin energy transduction: critical evaluation of non-traditional models for orthophosphate release

Release of the ATP hydrolysis product inorganic phosphate (Pi) from the active site of myosin is central in chemo-mechanical energy transduction and closely associated with the main force-generating structural change, the power-stroke. Despite intense investigations, the relative timing between Pi-release and the power-stroke remains poorly understood. This hampers in depth understanding of the production of force and motion by myosin in health and disease and also our understanding of myosin-active drugs. From the 1990s and up to today, models with the Pi-release either distinctly before or after the power-stroke, in unbranched kinetic schemes, have dominated the literature. However, in recent years, alternative models have emerged to explain apparently contradictory findings. Here, we first compare and critically analyze, three influential alternative models, either characterized by a branched kinetic scheme or by partial uncoupling of Pi-release and the power-stroke. Finally, we suggest critical tests of the models aiming for a unified picture.

biophysics↗