Fear extinction is a learning process which reduces conditioned fear responses within an experimental setting. It follows the same methodology used for exposure therapy in treatment for anxiety...Show moreFear extinction is a learning process which reduces conditioned fear responses within an experimental setting. It follows the same methodology used for exposure therapy in treatment for anxiety disorders. The current study investigated the effectiveness of social fear extinction (observing a model extinguish fear) compared to direct fear extinction (repeated exposure to the feared stimulus) in adolescents (N = 39, aged 13-17). Additionally, we examined the influence of past stressful life events on fear extinction learning. Participants underwent a fear conditioning paradigm with acquisition, extinction, and reinstatement phases. Self-reported fear expectancy ratings served as the primary outcome measure. Past stressful experiences were assessed using The Childhood Trauma Questionnaire-Short Form (CTQ-SF). A repeated-measures ANOVA revealed distinctive variation for the CS by condition effect in the extinction phase. An independent sample t test highlighted that individuals in the direct condition showed stronger differential US-expectancy rating compared to the social condition. There was a significant trial by condition interaction followed in the reinstatement phase where while both groups exhibited a decline in US expectancy ratings, however, the direct group demonstrated a more advanced reduction in fear expectancy. Furthermore, past stress did not significantly impact fear extinction learning in the sample. These findings suggest that, in our sample, direct fear extinction yielded an advantage over the social extinction group in reducing fear in adolescents. Future research should aim at carefully examining the nuanced aspects that facilitate fear extinction learning. Factors like individual characteristics of the sample, model, or pre and post condition affects can be considered. Keywords: Fear extinction, social learning, adolescents, stress, anxiety disorderShow less
Background. This study is part of ‘RESIST’; a longitudinal study where the development of antisocial behaviour is studied from late childhood to early adulthood. All the participants have been in...Show moreBackground. This study is part of ‘RESIST’; a longitudinal study where the development of antisocial behaviour is studied from late childhood to early adulthood. All the participants have been in contact with the police, for committing an offence, before the age of twelve. Objective. The aim of this study is two- fold. Firstly, to investigate the development of antisocial behaviour from late childhood to early adulthood. Secondly, to investigate the social demographic characteristics whether they act as risk factors or protective factors to the desistance or persistence of antisocial behaviour. Methods. The main study consisted of five main time points. This thesis investigated three main time- points (TP): TP1; late childhood (N=298), TP4; adolescence (N=150), and TP5 early adulthood (N=73). Standard psychological instruments were used to investigate antisocial behaviour (DISC-IV, MINI and ASR) as well as the sociodemographic characteristics of the participants (SAHA). The desistance or persistence of antisocial behaviour from late childhood to early adulthood was statistically investigated using Repeated Measures ANOVA. Correlation and regression analysis are used to investigate whether there is a relationship and effect between these sociodemographic characteristics and the development of antisocial behaviour. Results. From late childhood (M=11.74) to adolescence (M=5.94) there is a statistically significant decrease of antisocial behaviour (F (1, 59) = 15.68, p < .001). Three main trajectories are outlined (1) the majority of the childhood- onset offenders desist from antisocial behaviour by the time they are adolescents, (2) only a small percentage persist up to their early adolescence and (3) a percentage persist up to their adulthood. Being associated with delinquent peers (β = 0.63, t = 0.36, p= 0.03) significantly predicts antisocial behaviour in adulthood. While, high parental supervision (β = 0.45, t = 2.8, p= 0.01) significantly predicts having an ASPD Diagnosis in adulthood. Additionally, a negative linear relationship between parental warmth and ASPD symptoms in adulthood was found. (r = -0.26, p= 0.04). Conclusion. These findings help to provide information on patterns of how early onset of delinquent behaviour progresses and develops over time. Furthermore, it also sheds light that delinquent peers and parental supervision act as a risk factor for persistence of antisocial behaviour. Whilst parental warmth acts as a protective factor for the desistance of antisocial behaviour. These findings aid interventions to be more specific and effective.Show less
Fear is a crucial defence mechanism that is aroused by an imminent threat and prepares an organism to take action. However, unnecessary fears that persist may lead to anxiety and stress-related...Show moreFear is a crucial defence mechanism that is aroused by an imminent threat and prepares an organism to take action. However, unnecessary fears that persist may lead to anxiety and stress-related disorders. Therefore, the extinction of a fear response is important. During the hormonal, brain and social changes in adolescence, the ability to extinct fears seems to decline. In this study we examined the role of pubertal development and peer attachment on fear extinction in 107 healthy participants between 9 and 12 years old. During this study, participants were shown natural looking faces. One of the faces (CS+) was presented together with an aversive unconditioned stimulus (A loud scream in combination with an anxious looking face (US)). The other natural looking face (CS-) was not presented with this aversive stimulus (US). During the fear extinction phase, both CS’s were shown without the US. Thereafter, the reinstatement phase took place, during which the fear reaction was first reignited again by showing the US three times again. This fear then was extinct again during the test phase by showing the CS’s without US. The fear acquisition seemed to have worked for girls only. However, boys were able to differentiate between the CS’s during fear extinction and might have learned slowly. During fear extinction, there was no decrease in CS differentiation, meaning that fear extinction did not work as expected. No effect of pubertal development nor peer attachment was found. The reinstatement phase seemed successful. During the test phase was found that pre-puberty boys show a general differential fear response, but boys in puberty do not show this general differential fear response. Thus, boys in puberty seem to show stronger recurrence of a differential fear response after reinstatement. This effect was not found in girls. Lastly, boys with high peer attachment seemed to have better fear extinction during the test phase compared to boys with low peer attachment, meaning that peer attachment may serve as a protective factor. This study might help develop research based on pubertal development or help future research based on peer support and social learning.Show less
