Biology subjects

van Reekum, C.

Publications and source records attributed to van Reekum, C..

4 recordsLinked to original sources

bioRxiv2022

Broad Brain Networks Support Curiosity-Motivated Incidental Learning Of Naturalistic Dynamic Stimuli With And Without Monetary Incentives

Curiosity - the intrinsic desire to know - is a concept central to the human mind and knowledge acquisition. Experimental studies on information-seeking have found that curiosity facilitates memory encoding and exhibits similar reward,ng properties as extrinsic rewards/incentives by eliciting a dopaminergic response. However, it is not clear whether these findings hold with more naturalistic dynamic stimuli and how the joint effect of curiosity and extrinsic incentive manifests in learning and neural activation patterns. Herein, we presented participants with videos of magic tricks across two behavioural (N1 = 77, N2 = 78) and one fMRI study (N = 50) and asked them to rate subjective feelings of curiosity, while also performing a judgement task that was incentivised for the half of participants. Incidental memory for the magic trick was tested a week later. The integrated results showed that both curiosity and availability of extrinsic incentives enhanced encoding but did not interact with each other. However, exploratory analyses showed that curiosity and monetary incentives were associated with recollection and familiarity differently, suggesting the involvement of different encoding mechanisms. Analysis of the fMRI data using the intersubject synchronisation framework showed that, while the effects of curiosity on memory were located in the hippocampus and dopaminergic brain areas, neither the effects of curiosity nor incentives themselves were found in the often-implicated reward network, but instead were associated with cortical areas involved in processing uncertainly and attention. These results suggest that curiosity recruits broader brain networks than what was implicated in the previous literature when investigated with dynamic stimuli.

neuroscience↗

bioRxiv2020

Intolerance of uncertainty is associated with heightened responding in the prefrontal cortex during instructed threat of shock

Heightened responding to uncertain threat is considered a hallmark of anxiety disorder pathology. Here, we sought to determine if individual differences in self-reported intolerance of uncertainty (IU), a key transdiagnostic dimension in anxiety-related pathology, underlies differential recruitment of neural circuitry during instructed outcome uncertainty of threat (n = 42). In an instructed threat of shock task, cues signalled uncertain threat of shock (50%) or certain safety from shock outcomes. Ratings of arousal and valence, skin conductance response (SCR) and functional magnetic resonance imaging were acquired. Overall, participants displayed greater ratings of arousal and negative valence, SCR, and amygdala activation to uncertain threat vs. safe cues. IU was not associated with greater arousal ratings, SCR or amygdala activation to uncertain threat vs. safe cues. However, we found that high IU was associated with greater ratings of negative valence and greater activity in the medial prefrontal cortex and dorsomedial rostral prefrontal cortex to uncertain threat vs safe cues. These findings suggest that during instructed outcome uncertainty of threat, individuals high in IU rate uncertain threat as aversive and engage prefrontal cortical regions known to be involved in safety-signalling and conscious threat appraisal. Taken together, these findings highlight the potential of IU in modulating safety-signalling and conscious appraisal mechanisms in situations with instructed outcome uncertainty of threat, which may be relevant to models of anxiety-related pathology.

neuroscience↗

bioRxiv2019

Longitudinal change in executive function is associated with impaired top-down frontolimbic regulation during reappraisal in older adults

Networks in the prefrontal cortex (PFC) that are important for executive function are also engaged in adaptive responding to negative events. These networks are particularly vulnerable to age-related structural atrophy and an associated loss of executive function, yet existing evidence suggests preserved emotion processing ability in aging. Using longitudinally acquired data from a battery of cognitive tasks, we defined a metric for the rate of decline of executive function. With this metric, we investigated relationships between changes in executive function and emotion reappraisal ability and brain structure, in older adults using functional and structural MRI. During task-based fMRI, participants were asked to cognitively reappraise negatively valenced images. We hypothesised one of two associations with decreasing executive function over time: 1) a decreased ability to reappraise reflected in decreased PFC and increased amygdala activation, or 2) a neural compensation mechanism characterised by increased PFC activation but no differential amygdala activation. Structurally, for a decreased reappraisal ability, we predicted a decrease in grey matter in PFC and/or a decrease of white matter integrity in amygdala-PFC pathways. Neither of the two hypotheses relating to brain function were completely supported, with the findings indicating a steeper decline in executive function associated with both increased PFC and increased left amygdala activity when reappraising negative stimuli. In addition, white matter integrity of the uncinate fasciculus, a primary white matter tract connecting the amygdala and ventromedial areas of PFC, was lower in those individuals who demonstrated a greater decrease in executive function. These findings highlight that when cognitive ability diminishes, active top-down emotional control is compromised.

neuroscience↗

bioRxiv2018

Knowledge is power: Contingency instruction promotes threat extinction in high intolerance of uncertainty individuals

Extinction-resistant threat is considered to be a central feature of pathological anxiety. Reduced threat extinction is observed in individuals with high intolerance of uncertainty (IU). Here we sought to determine whether contingency instructions could alter the course threat extinction for individuals high in IU. We tested this hypothesis in two identical experiments (Exp 1 n = 60, Exp 2 n = 82) where we recorded electrodermal activity during threat acquisition with partial reinforcement, and extinction. Participants were split into groups based on extinction instructions (instructed, uninstructed) and IU score (low, high). All groups displayed larger skin conductance responses to learned threat versus safety cues during threat acquisition, indicative of threat conditioning. In both experiments, only the uninstructed high IU groups displayed larger skin conductance responses to the learned threat versus safety cue during threat extinction. These findings suggest that uncertain threat during extinction maintains conditioned responding in individuals high in IU.

neuroscience↗