Biology subjects

Lonsdorf, T. B.

Publications and source records attributed to Lonsdorf, T. B..

7 recordsLinked to original sources

bioRxiv2026

Anxiety-Related Traits Are Associated with Subjective Biases but not Altered Threat-Safety Discrimination

Anxiety-related traits (ARTs) have been linked to altered fear learning, but previous studies have typically examined different experimental phases and response systems, limiting the comparability of findings and the accumulation of consistent evidence. Here, we comprehensively examined associations between ARTs and fear conditioning across acquisition, extinction and renewal and across subjective, physiological and neural response systems in a well-powered sample (N = 267) using a two-day differential conditioning paradigm. ARTs were operationalized as a composite of trait anxiety, neuroticism, and intolerance of uncertainty and conditioned responding was assessed using skin conductance responses, fear-potentiated startle, US expectancy ratings, fear ratings, and functional magnetic resonance imaging. Higher ARTs were consistently associated with elevated subjective fear and US expectancy to both threat and safety cues during extinction and renewal, without corresponding elevations in physiological responding. At the same time, ARTs were not associated with threat-safety discrimination in subjective or physiological measures across phases, while neural associations were limited to reduced dorsal anterior cingulate cortex discrimination during early renewal. These findings suggest that ARTs are characterized by a CS unspecific cognitive bias toward heightened threat expectancy and evaluation rather than altered associative fear learning, highlighting the importance of distinguishing conditioned discrimination from general levels of responding across response systems.

neuroscience↗

bioRxiv2026

Recent Adversity Shapes Autonomic and Neural Threat Learning and Retrieval Under Imminent Threat: A Prospective Longitudinal Study

Recent adversity (RA) increases the risk of later mental health problems, but the mechanisms underlying this association remain largely unclear. Altered associative learning and specifically threat learning processes may constitute a potential pathway. Cross-sectional studies link RA to reduced threat-safety discrimination, a process crucial for adaptive functioning; however, longitudinal evidence allowing for more causal conclusions is lacking. In this prospective longitudinal study, 69 healthy participants completed fear acquisition, 24h-delayed extinction training and a reinstatement-test at two measurement time points six months apart (T0 and T1). We captured exposure to RA between T0 and T1 as well as autonomic and neural responses (SCRs and BOLD-fMRI), fear ratings, and salivary and hair cortisol at both assessments. During acquisition training, at the beginning of extinction (i.e., fear recall) and reinstatement-test at T1, RA-exposed individuals showed less autonomic threat-safety discrimination than unexposed individuals, mainly driven by blunted threat signal responding. These group differences predicted depression levels at the 1 and 1.5 year follow-ups and were mirrored by distinct activation in key fear-related brain regions, including striatal regions, thalamus, vmPFC, insula, and amygdala, whereas self-reported fear was unrelated to RA. In conclusion, across multiple outcomes, RA shapes threat learning and retrieval under conditions of (potential) imminent threat, with reduced autonomic threat discrimination prospectively predicting elevated depressive symptoms at 1- and 1.5-year follow-up. Overall, these findings implicate altered threat learning and retrieval processes as a potential mechanistic pathway through which RA becomes biologically embedded, potentially elevating psychopathological risk.

physiology↗

bioRxiv2024

Physiological Harmony or Discord? Unveiling the Correspondence Between Subjective Arousal, Valence and Physiological Responses

Affective experiences are inevitably accompanied by physiological changes, however it is still a matter of intense debate whether events evoking similar affective experiences produce comparable physiological responses (fingerprint hypothesis) or variation is the norm within individuals (population hypothesis). We reanalyzed data from two independent samples (N = 491; N = 64), using representational similarity analysis (RSA) to examine the trial-by-trial similarity patterns of subjective experience of valence and arousal and affect-related physiological measures (skin conductance [SCR] and startle blink responses). Across different affect-inducing (passive picture viewing, passive sound listening, imagery tasks) tasks and samples (Ns=491, 64), we observed strong-to-decisive evidence for a correspondence between SCR and startle responses and models of arousal and valence that assume variation, especially between trials generally evoking higher responses. Our results show that similar affective experiences are rather reflected by distinct physiological responses and emphasize the importance of considering intraindividual variability in future studies to better understand how physiological changes contribute to conscious affective experiences in humans.

neuroscience↗

bioRxiv2023

Reduced discrimination between signals of danger and safety but not overgeneralization is linked to exposure to childhood adversity in healthy adults

Childhood adversity is a strong predictor of developing psychopathological conditions. Multiple theories on the mechanisms underlying this association have been suggested which, however, differ in the operationalization of exposure. Altered (threat) learning mechanisms represent central mechanisms by which environmental inputs shape emotional and cognitive processes and ultimately behavior. 1402 healthy participants underwent a fear conditioning paradigm (acquisition training, generalization), while acquiring skin conductance responses (SCRs) and ratings (arousal, valence, and contingency). Childhood adversity was operationalized as (1) dichotomization, and following (2) the specificity model, (3) the cumulative risk model, and (4) the dimensional model. Individuals exposed to childhood adversity showed blunted physiological reactivity in SCRs, but not ratings, and reduced CS+/CS-discrimination during both phases, mainly driven by attenuated CS + responding. The latter was evident across different operationalizations of exposure following the different theories. None of the theories tested showed clear explanatory superiority. Notably, a remarkably different pattern of increased responding to the CS-is reported in the literature for anxiety patients, suggesting that individuals exposed to childhood adversity may represent a specific sub-sample. We highlight that theories linking childhood adversity to (vulnerability to) psychopathology need refinement.

neuroscience↗

bioRxiv2022

Robust group- but limited individual-level (longitudinal) reliability and insights into cross-phases response prediction of conditioned fear

Here we follow the call to target measurement reliability as a key prerequisite for individual-level predictions in translational neuroscience by investigating i) longitudinal reliability at the individual and ii) group level, iii) cross-sectional reliability and iv) response predictability across experimental phases. 120 individuals performed a fear conditioning paradigm twice six month apart. Analyses of skin conductance responses, fear ratings and BOLD-fMRI with different data transformations and included numbers of trials were conducted. While longitudinal reliability was generally poor to moderate at the individual level, it was good for acquisition but not extinction at the group-level. Cross-sectional reliability was satisfactory. Higher responding in preceding phases predicted higher responding in subsequent experimental phases at a weak to moderate level depending on data specifications. In sum, the results suggest the feasibility of individual-level predictions for (very) short time intervals (e.g., cross-phases) while predictions for longer time intervals may be problematic.

neuroscience↗

bioRxiv2019

The neurofunctional basis of affective startle modulation in humans - evidence from combined facial EMG-fMRI

The startle reflex, a protective response elicited by an immediate, unexpected sensory event, is potentiated when evoked during threat and inhibited during safety. In contrast to skin conductance responses or pupil dilation, modulation of the startle reflex is valence-specific and considered the cross-species translational tool for defensive responding.\n\nRodent models implicate a modulatory pathway centering on the brainstem (i.e., nucleus reticularis pontis caudalis, PnC) and the centromedial amygdala (CeM) as key hubs for flexibly integrating valence information into differential startle magnitude.\n\nWe employed innovative combined EMG-fMRI measurements in two independent experiments and samples and provide converging evidence for the involvement of these key regions in the modulatory acoustic startle reflex pathway in humans. Furthermore, we provide the crucial direct link between EMG startle eye-blink magnitude and neural response strength.\n\nWe argue that startle-evoked amygdala responding and its affective modulation may hold promise as an important novel tool for affective neuroscience.

neuroscience↗

bioRxiv2017

Individual differences in fear learning: Specificity to trait-anxiety beyond other measures of negative affect, and mediation via amygdala activation

Negative emotionality is a well-established and stable risk factor for affective disorders. Individual differences in negative emotionality have been linked to associative learning processes which can be captured experimentally in fear conditioning paradigms. Literature suffers from underpowered samples, suboptimal methods, and an isolated focus on single questionnaires and single outcome measures. Here, we apply multivariate and dimensional approaches for three commonly investigated questionnaires in the field (STAI-T, NEO-FFI Neuroticism, Intolerance of Uncertainty Scale) across multiple analysis units (ratings, skin conductance, startle, BOLD-fMRI) during fear acquisition-training in two large samples (NStudy1=356; NStudy2=113). We investigate whether the specific or shared variance of these questionnaires is linked with CS-discrimination in specific outcome measures (Study 1). We identify a significant negative association between STAI-T and CS-discrimination in SCRs and between Intolerance of Uncertainty and CS-discrimination in startle responding. Yet, correlation coefficients for all questionnaire-outcome measure combinations did not differ significantly from each other. In Study 2 the STAI-T score was positively associated with CS-discrimination in a number of brain areas linked to conditioned fear (amygdala, putamen, thalamus), but not to SCRs or ratings. Importantly, we replicate potential sampling biases between fMRI and behavioral studies regarding anxiety levels. We discuss the implications of these results.

neuroscience↗