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Selpien, H.

Publications and source records attributed to Selpien, H..

3 recordsLinked to original sources

Multi-modal brain properties are associated with interindividual differences in fear acquisition and extinction

Interindividual differences in fear acquisition and extinction have been related to variation in specific brain correlates. However, variability in experimental setups complicates the integration of findings. Here, we present a combined fear acquisition (n = 101) and extinction (n = 88) experiment in which both phenomena were related to brain correlates obtained via functional magnetic resonance imaging in healthy, young participants. Correlates included regional brain volume, cortical surface area and thickness, neurite density and orientation dispersion, structural and functional connectivity. Fear responses were quantified as changes in skin conductance. Data from 376 brain areas and 70,500 network connections were used as independent variables in regularized regression models. Regression models of fear acquisition could be obtained for all modalities but regional brain volume. There were 284 predictors of which 77 appeared in exactly two models and 19 in exactly three. The latter primarily included brain areas from the somatosensory, insular, cingulate, and frontal cortices. Fear extinction yielded regression models based on neurite density, structural connectivity, and functional connectivity with 112 predictors in total. Two predictors, located in the dorsolateral prefrontal cortex, replicated across exactly two regression models (neurite density and structural connectivity). This study is the first to investigate the neural correlates of both fear acquisition and extinction in an explorative, multi-modal fMRI approach. Results show that numerous brain regions contribute to fear conditioning, some of them via more than one correlate. These findings call for further research to examine the potential interplay between brain correlates shaping fear conditioning.

neuroscience↗

Conditioned fear reactions are associated with gray matter density but not cortical microstructure

Research has shown that fear acquisition, in reaction to potentially harmful stimuli or situations, is characterized by pronounced interindividual differences. It is likely that such differences are evoked by variability in the macro- and microstructural properties of brain regions involved in the processing of threat or safety signals from the environment. Indeed, previous studies have shown that the strength of conditioned fear reactions is associated with the cortical thickness or volume of various brain regions. However, respective studies were exclusively targeted at single brain regions instead of whole brain networks. Here, we tested 60 young and healthy individuals in a differential fear conditioning paradigm while they underwent fMRI scanning. In addition, we acquired T1-weighted and multi-shell diffusion-weighted images prior to testing. We used task-based fMRI data to define global brain networks which exhibited increased BOLD responses towards CS+ or CS- presentations, respectively. From these networks, we obtained mean values of gray matter density, neurite density, and neurite orientation dispersion. We found that mean gray matter density averaged across the CS+ network was significantly correlated with the strength of conditioned fear reactions quantified via skin conductance response. Measures of neurite architecture were not associated with conditioned fear reaction in any of the two networks. Our results extend previous findings on the relationship between brain morphometry and fear learning. Most importantly, our study is the first to introduce neurite imaging to fear learning research and discusses how its implementation can be improved in future research.

neuroscience↗

Fear learning sculpts functional brain connectivity at rest beyond the traditional fear network in humans

Neuroscientific research has identified specific brain networks involved in the acquisition of fear memories. Using fMRI to assess changes in resting-state functional connectivity (RSFC) induced by fear acquisition, single brain regions from these networks have also been linked to fear memory consolidation. However, previous studies only examined RSFC changes within restricted sets of brain regions or without a proper control group, leaving our knowledge about fear consolidation outside of traditional fear networks incomplete. Here, we tested a group of 84 healthy participants in a differential fear conditioning paradigm and quantified RSFC changes between 358 cortical and 16 subcortical brain areas. Subsequent to fear learning, 21 functional connections exhibited significant RSFC changes. Importantly, these connections were not restricted to the traditional fear networks but also comprised various frontal and visual areas. Our findings indicate that fear memory consolidation is a complex process that integrates relevant information across the entire brain.

neuroscience↗