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Singer, N.

Publications and source records attributed to Singer, N..

3 recordsLinked to original sources

Amygdala Self-Neuromodulation Capacity as a Window for Process-Related Network Recruitment

Neurofeedback (NF) has emerged as a promising avenue for demonstrating process-related neuroplasticity, enabling self-regulation of brain function. NF targeting the amygdala has drawn attention for therapeutic potential in psychiatry, by potentially harnessing emotion-regulation processes. However, not all individuals respond equally to NF training, possibly due to varying self-regulation abilities. This underscores the importance of understanding the mechanisms behind successful neuromodulation (i.e. capacity). This study aimed to investigate the establishment and neural correlates of neuromodulation capacity by using data from repeated sessions of Amygdala Electrical Finger Print (EFP)-NF and post-training fMRI-NF session. Results from 97 psychiatric patients and healthy participants revealed increased amygdala-EFP neuromodulation capacity over training, associated with post-training amygdala fMRI modulation-capacity and improvements in alexithymia. Individual differences in this capacity were associated with pre-training amygdala reactivity and initial neuromodulation success. Additionally, amygdala down-regulation during fMRI-NF co-modulated with other regions such as the posterior-insula and parahippocampal gyrus. This combined modulation better explained EFP-modulation capacity and improvement in alexithymia than the amygdala modulation alone, suggesting the relevance of this broader network to the gained capacity. These findings support a network-based approach for NF and highlight the need to consider individual differences in brain function and modulation capacity to optimize NF interventions.

neuroscience↗

Molecular Photoswitches Regulating the Activity of the Human Serotonin Transporter

Serotonin is an essential mediator regulating diverse neural processes, and its deregulation is related to debilitating neurological diseases. In particular, the human serotonin transporter (hSERT) is fundamental in completing the synaptic neural cycle by allowing the reuptake of serotonin. Its inhibition is particularly attractive, especially as a pharmacological target against depressive syndrome. Here, we analyze, by using long-range molecular dynamic simulations, the behavior of a molecular photoswitch whose cis- and trans-isomers inhibit the hSERT differently. In particular, we evidence the structural and molecular basis behind the higher inhibiting capacity of the cis-isomer, which blocks more efficiently the hSERT conformational cycle leading to serotonin uptake. TOC Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/558680v1_ufig1.gif" ALT="Figure 1"> View larger version (98K): org.highwire.dtl.DTLVardef@75d82dorg.highwire.dtl.DTLVardef@c38d43org.highwire.dtl.DTLVardef@6f3c90org.highwire.dtl.DTLVardef@f12399_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

Development and validation of an fMRI-informed EEG model of reward-related ventral striatum activation

Reward processing is essential for our mental-health and well-being. Here, we present the development and validation of a scalable fMRI-informed EEG model related to reward processing in the ventral-striatum (VS); a central reward circuit node. Simultaneous EEG/fMRI data were acquired from 17 healthy individuals listening to pleasurable music, and used to construct a one-class regression model for predicting the reward-related VS-BOLD signal using spectro-temporal features from the EEG. Validation analyses, applied on EEG/fMRI data from a different group (N=14), revealed that the EEG model predicted VS-BOLD activation from the simultaneous EEG to a greater extent than a model derived from another anatomical region. The VS-EEG-model was also modulated by musical pleasure and predictive of the VS-BOLD during a monetary reward task, further indicating it functional relevance. These findings provide compelling evidence for the use of a scalable yet precise EEG-only probe of VS-originated reward processing, which could serve for process specific neruo-monitoring and -modulation.

neuroscience↗