The ability to extract regularities from the environment is fundamental to both basic and higher-order cognitive functions. Previous findings showing that individuals are better able to remember emotional stimuli suggest that learning the regularities of emotional stimuli may be robust. Yet, little is known about how implicit learning is affected by emotional stimuli, and specifically by negative threatening stimuli. During the learning phase of a Visual Statistical Learning (VSL) task, participants viewed a stream of items with negative and neutral valence. They were unaware that the items recurred regularly as triplets. In a surprise recognition test followed the learning phase, participants were asked to judge which of two triplets—one real and the other a foil—was more familiar. The results of Experiment 1 indicated better statistical learning for negative triplets than for neutral triplets. Experiment 2 replicated this finding and showed that the negative triplet’s advantage was independent of the number of negative items comprising it, suggesting that the enhanced learning of negative triplets is not driven by a cumulative effect. Instead, we speculated that participants were able to use preceding items across repeating triplets to predict the appearance of negative items. Experiment 3 showed that the advantage for negative triplets is driven by individual items within the triplets. Together, these experiments offer valuable insights into how implicit learning such as VSL is affected by negative stimuli.
Extracting regularities and probabilities from the environment is a fundamental and critical ability in an ever-changing surrounding. Previous findings showed that people are highly efficient in learning these regularities and that emotional stimuli are better learned than neutral ones. Yet, the generality and the underlying mechanism of this benefit are poorly understood. Here, participants viewed a stream of images with negative and neutral valence. Unbeknownst, the items recurred in regularity as triplets. Then, to assess learning, a surprised familiarity test was conducted. The results of Experiment 1, using two sets of stimuli, found better statistical learning for negative triplets than for neutral triplets. Experiment 2 revealed similar benefits even when only a single negative item was in the triplet at the second or third position, suggesting the advantage is not cumulative. We speculated that the predictability of the negative items is driving the effect. Consequently, Experiment 3 confirmed that the memory for neutral items preceding negative items was better than for neutral items preceding neutral items. Together, these findings provide novel insights into the mechanism of how the learning of incidental temporal associations is influenced by negative stimuli and the role of predictability in the negative valence benefit.
Previous studies have indicated that socially-anxious individuals prefer to maintain a greater interpersonal distance from others, specifically from strangers. Notwithstanding, it has yet to be examined whether this preference for distance is associated with estimating the physical interpersonal distance in a distorted manner. In the current study, 100 participants performed a computerized task that measured estimated distance (Study 1). An additional sample of 75 participants performed the same task for the purpose of replication, and further took part in a new task that measured estimated distance from a stranger in a real-life setting (Study 2). In both studies social anxiety correlated with estimating the interpersonal distance from strangers as shorter. Furthermore, ones' preferred distance from a stranger was predicted by this distance estimation bias. Taken together, our findings are the first to reveal distance estimation bias in social anxiety, suggesting a role for distorted distance estimation in avoidance behavior.
Attention bias plays an important role in specific fears and phobias. Previous studies revealed that a-priori expectancies affect attention toward neutral stimuli (e.g., birds), but not threatening stimuli (e.g., spiders). The aim of the current study was to test whether this selective influence of expectancies on attention is specific to phylogenetic threat (i.e., spiders) or whether it can be generalized to ontogenetic threat (i.e., guns). Correspondingly, we directly compared expectancy effects on attentional allocation to phylogenetically vs. ontogenetically threatening stimuli. To this aim, expectancies were manipulated by presenting a cue indicating the likelihood of the appearance of a deviant picture in a visual search array. The array included eight distractors and one neutral (phone/bird) or threatening (gun/spider) deviant picture. In a comprehensive design, we examined the effects of stimulus type (phylogenetic/ontogenetic) and visual background (white and sterile/complex and ecological). Individual differences such intolerance of uncertainty and spider fear were also measured. Results showed that attention bias toward spiders does not extend to threatening ontogenetic stimuli (i.e., guns). Our previous findings on attention bias toward spiders were replicated and a correlation was found between attention bias toward spiders and pre-existing fear of spider levels. Additionally, a correlation was found between fear of spiders and intolerance of uncertainty. Together, these results suggest that expectancy and attentional processes may differ between ontogenetic and phylogenetic threat. Importantly, the effects of expectancy on attentional allocation depend on an interaction between the type of threat (ontogenetic/phylogenetic), visual factors, and individual differences.
Abstract Objective To test whether elevated blood pressure (BP) relates to grey matter volume (GMV) changes in young adults who had not previously been diagnosed as hypertensive (systolic BP (SBP)/diastolic BP (DBP)≥140/90 mmHg). Methods We associated BP with GMV from structural 3 Tesla T1-weighted MRI of 423 healthy adults between 19-40 years (mean age=27.7±5.3 years, 177 women, SBP/DBP=123.2/73.4±12.2/8.5 mmHg). Data originated from four previously unpublished cross-sectional studies conducted in Leipzig, Germany. We performed voxel-based morphometry on each study separately and combined results in image-based meta-analyses (IBMA) to assess cumulative effects across studies. Resting BP was assigned to one of four categories: (1) SBP<120 and DBP<80 mmHg, (2) SBP 120-129 or DBP 80-84 mmHg, (3) SBP 130-139 or DBP 85-89 mmHg, (4) SBP≥140 or DBP≥90 mmHg. Results IBMA yielded: (a) lower regional GMV was correlated with higher peripheral BP; (b) lower GMV with higher BP when comparing individuals in sub-hypertensive categories 3 and 2, respectively, to those in category 1; (c) lower BP-related GMV was found in regions including hippocampus, amygdala, thalamus, frontal and parietal structures (e.g. precuneus). Conclusions BP≥120/80 mmHg was associated with lower GMV in regions that have previously been related to GM decline in older individuals with manifest hypertension. Our study shows that BP-associated GM alterations emerge continuously across the range of BP and earlier in adulthood than previously assumed. This suggests that treating hypertension or maintaining lower BP in early adulthood might be essential for preventing the pathophysiological cascade of asymptomatic cerebrovascular disease to symptomatic end-organ damage, such as stroke or dementia.
