Preventing the development of observationally learnt fears in children by devaluing the model's negative response

Vicarious learning has become an established indirect pathway to fear acquisition. It is generally accepted that associative learning processes underlie vicarious learning; however, whether this association is a form of conditioned stimulus-unconditioned stimulus (CS-US) learning or stimulus-response (CS-CR) learning remains unclear. Traditionally, these types of learning can be dissociated in a US revaluation procedure. The current study explored the effects of post-vicarious learning US revaluation on acquired fear responses. Ninety-four children (46 males and 48 females) aged 6 to 10 years first viewed either a fear vicarious learning video or a neutral vicarious learning video followed by random allocation to one of three US revaluation conditions: inflation; deflation; or control. Inflation group children were presented with still images of the adults in the video and told that the accompanying sound and image of a very fast heart rate monitor belonged to the adult. The deflation group were shown the same images but with the sound and image of a normal heart rate. The control group received no US revaluation. Results indicated that inflating how scared the models appeared to be did not result in significant increases in children's fear beliefs, avoidance preferences, avoidance behavior or heart rate for animals above increases caused by vicarious learning. In contrast, US devaluation resulted in significant decreases in fear beliefs and avoidance preferences. Thus, the findings provide evidence that CS-US associations underpin vicarious learning and suggest that US devaluation may be a successful method for preventing children from developing fear beliefs following a traumatic vicarious learning episode with a stimulus

Effect of vicarious fear learning on children's heart rate responses and attentional bias for novel animals

Research with children has shown that vicarious learning can result in changes to 2 of Lang's (1968) 3 anxiety response systems: subjective report and behavioral avoidance. The current study extended this research by exploring the effect of vicarious learning on physiological responses (Lang's final response system) and attentional bias. The study used Askew and Field's (2007) vicarious learning procedure and demonstrated fear-related increases in children's cognitive, behavioral, and physiological responses. Cognitive and behavioral changes were retested 1 week and 1 month later, and remained elevated. In addition, a visual search task demonstrated that fear-related vicarious learning creates an attentional bias for novel animals, which is moderated by increases in fear beliefs during learning. The findings demonstrate that vicarious learning leads to lasting changes in all 3 of Lang's anxiety response systems and is sufficient to create attentional bias to threat in children

Effects of vicarious disgust learning on the development of fear, disgust and attentional biases in children

Fear and disgust are defensive emotions that have evolved to protect us from harm. While fear is thought to elicit an instinctive response to deal with immediate threat, disgust elicits immediate sensory rejection to avoid contamination. One mechanism through which disgust and fear may be linked is via attentional bias towards threat. Attentional bias is a well-established feature of anxiety disorders and is known to increase following vicarious fear learning. However, the contribution of vicarious learning to the development of disgust-related attentional biases is currently unknown. Furthermore, the influence of individual differences in disgust propensity and disgust sensitivity on fear and disgust responses has not been investigated in the context of vicarious learning. Therefore, 53 children aged 7-9 years were randomly assigned to receive either fear vicarious learning or disgust vicarious learning. Children’s fear beliefs, disgust beliefs, avoidance preferences and attentional bias were measured at baseline and post-learning. Findings demonstrated increased fear and disgust responding to stimuli following disgust and fear vicarious learning. Crucially, the study provided the first evidence that disgust vicarious learning can create an attentional bias for threat in children similar to that created via fear vicarious learning. However, there was no relationship between disgust propensity and sensitivity and vicariously acquired increases in fear, disgust and attention. In conclusion, both fear and disgust vicarious learning can create attentional bias, allowing rapid detection of potentially harmful stimuli. This effect could contribute to fear development and is found even in children who are not particularly high in disgust proneness

Reductions in children's vicariously learnt avoidance and heart rate responses using positive modeling

Recent research has indicated that vicarious learning can lead to increases in children's fear beliefs and avoidance preferences for stimuli and that these fear responses can subsequently be reversed using positive modeling (counterconditioning). The current study investigated children's vicariously acquired avoidance behavior, physiological responses (heart rate), and attentional bias for stimuli and whether these could also be reduced via counterconditioning. Ninety-six (49 boys, 47 girls) 7- to 11-year-olds received vicarious fear learning for novel stimuli and were then randomly assigned to a counterconditioning, extinction, or control group. Fear beliefs and avoidance preferences were measured pre- and post-learning, whereas avoidance behavior, heart rate, and attentional bias were all measured post-learning. Control group children showed increases in fear beliefs and avoidance preferences for animals seen in vicarious fear learning trials. In addition, significantly greater avoidance behavior, heart rate responding, and attentional bias were observed for these animals compared to a control animal. In contrast, vicariously acquired avoidance preferences of children in the counterconditioning group were significantly reduced post-positive modeling, and these children also did not show the heightened heart rate responding to fear-paired animals. Children in the extinction group demonstrated comparable responses to the control group; thus the extinction procedure showed no effect on any fear measures. The findings suggest that counterconditioning with positive modelling can be used as an effective early intervention to reduce the behavioral and physiological effects of vicarious fear learning in childhood

Traumatic events and PTSD among Palestinian children and adolescents : the effect of demographic and socioeconomic factors

Background: This study investigates the prevalence of traumatic events and Posttraumatic Stress Disorder (PTSD) among Palestinian children and adolescents in the Gaza Strip. Methods: The sample consists of 1029 school pupils (11-17 years old): 533 (51.8%) were female and 496 (48.2%) were male. War-Traumatic Events Checklist (W-TECh) Post-Traumatic Stress Disorders Symptoms Scale (PTSDSS) were used. Results: 88.4% (N = 909) experienced personal trauma, 83.7% (N = 861) witnessed trauma to others, and 88.3% (N = 908) observed demolition of property during the war. Compared to girls, boys showed significantly more exposure to all three event types as well as overall traumatic events. Results also demonstrated that the prevalence of DSM-V PTSD diagnosis was 53.5% (N = 549). Further, children who had experienced personal trauma, trauma to others, and the demolition of property were significantly more likely to be diagnosed with PTSD compared to those who had not even when adjusting for demographic and socioeconomic factors

Inhibition of vicariously learned fear in children using positive modeling and prior exposure

One of the challenges to conditioning models of fear acquisition is to explain how different individuals can experience similar learning events and only some of them subsequently develop fear. Understanding factors moderating the impact of learning events on fear acquisition is key to understanding the etiology and prevention of fear in childhood. This study investigates these moderators in the context of vicarious (observational) learning. Two experiments tested predictions that the acquisition or inhibition of fear via vicarious learning is driven by associative learning mechanisms similar to direct conditioning. In Experiment 1, 3 groups of children aged 7 to 9 years received 1 of 3 inhibitive information interventions—psychoeducation, factual information, or no information (control)—prior to taking part in a vicarious fear learning procedure. In Experiment 2, 3 groups of children aged 7 to 10 years received 1 of 3 observational learning interventions—positive modeling (immunization), observational familiarity (latent inhibition), or no prevention (control)—before vicarious fear learning. Results indicated that observationally delivered manipulations inhibited vicarious fear learning, while preventions presented via written information did not. These findings confirm that vicarious learning shares some of the characteristics of direct conditioning and can explain why not all individuals will develop fear following a vicarious learning event. They also suggest that the modality of inhibitive learning is important and should match the fear learning pathway for increased chances of inhibition. Finally, the results demonstrate that positive modeling is likely to be a particularly effective method for preventing fear-related observational learning in childre

Vicarious learning of children’s social anxiety-related fear beliefs and emotional Stroop bias

Models of social anxiety suggest that negative social experiences contribute to the development of social anxiety, and this is supported by self-report research. However, there is relatively little experimental evidence for the effects of learning experiences on social cognitions. The current study examined the effect of observing a social performance situation with a negative outcome on children’s (8 to 11 years old) fear-related beliefs and cognitive processing. Two groups of children were each shown 1 of 2 animated films of a person trying to score in basketball while being observed by others; in 1 film, the outcome was negative, and in the other, it was neutral. Children’s fear-related beliefs about performing in front of others were measured before and after the film and children were asked to complete an emotional Stroop task. Results showed that social fear beliefs increased for children who saw the negative social performance film. In addition, these children showed an emotional Stroop bias for social-anxiety-related words compared to children who saw the neutral film. The findings have implications for our understanding of social anxiety disorder and suggest that vicarious learning experiences in childhood may contribute to the development of social anxiety

Stimulus fear relevance and the speed, magnitude, and robustness of vicariously learned fear

Superior learning for fear-relevant stimuli is typically indicated in the laboratory by faster acquisition of fear responses, greater learned fear, and enhanced resistance to extinction. Three experiments investigated the speed, magnitude, and robustness of UK children's (6-10 years; N = 290; 122 boys, 168 girls) vicariously learned fear responses for three types of stimuli. In two experiments, children were presented with pictures of novel animals (Australian marsupials) and flowers (fear-irrelevant stimuli) alone (control) or together with faces expressing fear or happiness. To determine learning speed the number of stimulus-face pairings seen by children was varied (1, 10, or 30 trials). Robustness of learning was examined via repeated extinction procedures over 3 weeks. A third experiment compared the magnitude and robustness of vicarious fear learning for snakes and marsupials. Significant increases in fear responses were found for snakes, marsupials and flowers. There was no indication that vicarious learning for marsupials was faster than for flowers. Moreover, vicariously learned fear was neither greater nor more robust for snakes compared to marsupials, or for marsupials compared to flowers. These findings suggest that for this age group stimulus fear relevance may have little influence on vicarious fear learning

Actuator and electronics packaging for extrinsic humanoid hand

The lower arm assembly for a humanoid robot includes an arm support having a first side and a second side, a plurality of wrist actuators mounted to the first side of the arm support, a plurality of finger actuators mounted to the second side of the arm support and a plurality of electronics also located on the first side of the arm support