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Background: Individuals with binge eating disorder (BED) experience a loss of control (i.e., poor inhibitory control) during binge eating, where stress is a common antecedent for binge episodes. However, few studies examine acute stress in BED and, to date, psychosocial stress relationships with inhibitory control are unexamined. Purpose: The current study investigated acute psychosocial stress effects on inhibitory control in BED. Additionally, inhibitory control relationships with BED treatment outcome were explored. Methods: Thirty-three individuals with BED were randomized to a stress (n = 17) or no stress condition (n = 16). All completed self-report measures including the Profile of Mood States and the Binge Urge Scale. Following the stressor, individuals completed the Stop-Signal Task (SST), a well-validated measure of inhibitory control. Relationships between post-stress anxiety with inhibitory control and eating pathology were explored. Furthermore, treatment outcome relationships with levels of inhibitory control, and negative urgency (an impulsive personality trait) were explored. Results: In the stress condition, individuals reported increased state anxiety immediately following stress, but experienced a decrease back to baseline levels of anxiety by the end of the SST. Stress resulted in impaired inhibitory control performance on the SST. Binge urges increased across both conditions over time. Measures of inhibitory control and negative urgency did not relate to treatment outcome. Conclusion: This study is novel in directly examining psychosocial stress effects on inhibitory control, which has not been studied in BED. These results show subjective stress effects in BED are short-lived; however, behaviourally, stress has a lingering effect on inhibitory control. Increasing binge urges across the experimental session in the no stress condition suggests a role for generalized anxiety on this impulse. These findings have clinical implications for binge urges as a therapeutic target, and for informing individuals with BED about the implications of stress on their binge eating. / Thesis / Master of Science (MSc)

Shyness is highly related to internalizing problems. However, not all shy children develop serious internalizing problems (IP). The aim of the current study was to identify the endogenous factors that might contribute to the resilience process from a self-regulation perspective. Participants included 73 children (33 boys; 40girls) who visited the lab at 6 and 9 years of age. Shyness, attentional control (AC), inhibitory control (IC), frontal electroencephalogram (EEG) asymmetry were measured at both 6 and 9 years using age appropriate questionnaires and tasks. Results indicated that age 6 shyness did not directly predict age 9 IP; instead it indirectly predicted IP through age 9 shyness. Neither AC, IC, frontal EEG asymmetry, nor the stability of frontal EEG asymmetry moderated the association between age 6 shyness and age 9 IP. However, there was a positive concurrent association between shyness and IP at 9 years. In addition, AC and IC moderated the shyness-IP association at age 9. Shyness was significantly associated with IP only when children had low AC or IC, but not when children had high AC or IC. / Master of Science / Shyness is highly related to internalizing problems. However, not all shy children develop serious internalizing problems (IP). The aim of the current study was to identify the within-individual factors that might protect children away from having IP from a self-regulation perspective. Participants included 73 children (33 boys; 40girls) who visited the lab at 6 and 9 years of age. Shyness, attentional control (AC), inhibitory control (IC), frontal electroencephalogram (EEG) asymmetry were measured at both 6 and 9 years using age appropriate questionnaires and tasks. Results indicated that children who are shy at 6 years old may not have IP at 9 years old. Instead children who are shy at 6 years old tend to be shy at 9 years old. And those who are shy at 9 years old are more likely to have IP at the same period of time. Neither AC, IC, frontal EEG asymmetry, nor the stability of frontal EEG asymmetry affect the direction or degree of the association between age 6 shyness and age 9 IP. In addition, AC and IC affect the concurrent shyness-IP association at age 9. Shyness was significantly associated with IP only when children had low AC or IC, but not when children had high AC or IC.

As virtual experiences are rapidly substituting a significant proportion of in-person interactions during the COVID pandemic, it is critical to monitor the effect of screen exposure time on developing children’s behavior and nervous system. Screen use boosts information accessibility and, therefore, may delay the development of the inhibitory control networks in children, who are vulnerable to immediate reward-orientated tendencies and not yet capable of controlling their impulsivity. Therefore, it was hypothesized that as children become more exposed to screens, the development of the inhibitory control network would be delayed and their reward sensitivity will be augmented. Using the ABCD Study Data Repository, 8,334 children’s behavioral and neural data (aged 9-11) were included. Robust mediation analysis and correlation analysis were used to investigate how Screen Time interacts with children’s reward-orientated tendency (e.g. Behavioral approach system, BAS) and the brain's inhibitory network. Intrinsic Frontoparietal Network-Striatum (FPN-Striatum) connectivity strength was used as neural indices of the inhibitory control quality in children. Results showed that Screen Time significantly mediated the relationship between BAS and both waves of the intrinsic inhibitory process. A higher BAS was linked to a longer Screen Time and weaker inhibitory network connectivity. This complete/full mediation model indicates that Screen Time negatively influenced the strength of FPN-Striatum connectivity. In conclusion, the study revealed specific behavioral and neural correlates of screen exposure using a large database, and suggested that increasing screen exposure time may impair the inhibitory capability and increase impulsivity in children. / M.S. / The current study explored the effect of daily screen exposure in pre-adolescent children to provide an important springboard for future work in protecting developing children against the negative impacts of screen use, which has increased significantly during the COVID-19 pandemic. Over 8,000 children’s data from the Adolescent Brain Cognitive Development (ABCD) project was included and found that an increased daily screen exposure time is linked to an inefficient inhibitory control system in the brain. As children’s inhibitory control systems are still developing, this negative effect further hinder the maturation of inhibitory-control systems two years later. Given that the virtual movement is irreversible, the results provide scientific evidence that a balance between screen time and non-screen activities is required for developing children.

Fearful temperament represents one of the robust predictors of the development of child and adolescent anxiety. Not all children with fearful temperament unvaryingly develop anxiety, however. Diverse processes resulting from the interplay among attention, cognitive control, and motivational system drive the trajectories toward more adaptive or maladaptive directions. In this study, I examined various factors that underlie the association between fearful temperament at age 9 and adolescent anxiety symptoms including attention biases, different components of effortful control, and frontal EEG asymmetry. 78 children participated in this study. Results indicate that fearful temperament at age 9 significantly predicted adolescent anxiety symptoms. This association, however, was moderated by children's effortful control and frontal EEG asymmetry at age 9. Specifically, fear at 9 years predicted adolescent anxiety only when children had low attentional control, low inhibitory control, low activation control, and exhibited greater right activation from baseline to task. The associations between AB and fearful temperament as well as anxiety were not significant. The association between fear at 9 years and sustained AB during adolescence, however, was moderated by children's attentional control, inhibitory control, and frontal EEG asymmetry at age 9. Specifically, fear predicted attention biases away from threat when children had high attentional control, high inhibitory control, and showed greater left activation. The findings will be discussed in terms of the roles of attention biases in the development of anxiety and how different components of effortful control and frontal EEG asymmetry contribute to the resilience process. / Doctor of Philosophy / Anxiety disorders represent one of the most commonly occurring mental health problems in childhood and adolescence. Children who tend to show wariness and distress to negative stimuli are more likely to have anxiety. Not all children with fearful temperament develop anxiety, however. Certain individual characteristics can protect fearful children from having anxiety symptoms. In this study, I examined the roles of attentional biases toward threat (AB), different components of self-regulation (EC), and the asymmetrical frontal brain activation (FA) in changing the relation between fearful temperament and anxiety. 78 children participated in this study. Results indicated that adolescents were at higher risk for anxiety if they showed high fearful temperament at age 9. However, the risk could be attenuated if children were better able to control their attention and behaviors, and exhibited greater left activation from resting to a mildly stressful situation at age 9. In addition, fearful children were better able to direct attention away from threat during adolescence if they were better able to control their attention and behaviors, and exhibited greater left activation from resting to a mildly stressful situation at age 9. The findings provide suggestions for early identification and intervention of children who are more vulnerable to anxiety during adolescence.

Alcohol intoxication represents one situation an individual might increase their amount of risk taking when driving. This dissertation is comprised of three studies that investigate the mechanisms by which alcohol increases driver risk-taking. Study 1 examined the effect of alcohol on driver risk-taking using a proxemics approach. The study also tested whether alcohol-induced increases in risky driving co-occurred with pronounced impairment in the driver’s skill. The study also examined whether the most disinhibited drivers were also the riskiest. Indeed, alcohol increased driver risk-taking and impaired driving skill. The study also revealed risky driving can be dissociable from impairing effects on driver skill and that poor inhibitory control is selectively related to elevated risky driving. Studies 2 and 3 built on this work by addressing whether the apparent dissociation between behavioral measures of driver risk and skill was mediated by perceptions the drivers held. While maintaining the distinction between driver risk and skill, Study 2 tested the relationship between drivers’ BAC estimations and their tendency to take risks on the roadway. Drivers who estimated their BAC to be lower were the riskiest drivers following both alcohol and placebo. Study 3 addressed whether risky driving could be increased by environmental factors that shape perceptions the driver holds. There is evidence post-licensure training programs might inadvertently generate overconfidence in drivers’ perceived ability to operate a motor vehicle and thus fail to perceive dangers normally associated with risky driving behavior. To test this hypothesis, twenty-four drivers received either advanced skill training or no training in a driving simulator. Drivers who received skill training showed increased risky driving under alcohol whereas those who received no training tended to decrease their risk taking. Trained drivers also self-reported more confidence in their driving ability. Taken together, these studies represent a large step towards the betterment of laboratory-based models of driving behavior. The work highlights the importance of distinguishing between driver risk-taking and driving skill. The studies also identified that drivers’ personal beliefs influence alcohol-induced risky driving; this suggests training programs focused on correcting drivers’ misconceptions might be most efficacious in reducing their risk taking on the roadway.

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Made available in DSpace on 2016-03-22T17:27:34Z (GMT). No. of bitstreams: 1 Tese Marta Tessmann Bandeira.pdf: 1779478 bytes, checksum: 08ef43dde2abf1599e6caa409a3cc035 (MD5) Previous issue date: 2014-12-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The main aim of this dissertation is to investigate the cognitive differences, specially the executive functions: memory, inhibitory control and attention, among monolinguals and bilinguals in two different moments. The first moment happened in 2008 when, for the Master s thesis, the same questions were studied with children in the town of Arroio do Padre, located in the South of Brazil which was colonized by Pomeranians and which localization, with a very distinct geography, makes the access to the most common means of communication more difficult. This fact might help the language preservation that was brought by the immigrants by the end of the XIX century and still in use in this town today. In the present study, the research first done in 2008 is made wider, so the same participants that did the experiments in 2008 were contacted and did the experiments again in 2012, making this a longitudinal study. To complete the data, children and adolescents, monolinguals and bilinguals from Scotland, UK, also participated in this study doing the same experiments, making it possible to observe if bilinguals that have as their mother tongue a not written language, as the Pomeranian, and those who use their first language to do all kinds of tasks including reading and writing, as it happens with the German for the Scottish bilinguals, show any difference in the executive functions investigated in this study. So, the specific aims of this dissertation are briefly to compare children and teenagers, Brazilians and Scottish, monolinguals and bilinguals in tasks involving the general executive control. These tasks are divided in non-verbal (Simon Task) and verbal (Stroop Test). The results found in this dissertation can be divided into two big groups according to the tasks and their specifications. The Simon Task which is a non-verbal task, measures some executive functions, the inhibitory control and attention, in this task the bilingual participants show some advantage. When analyzed the results of the Stroop Test, which is a verbal task, we cannot affirm that there is advantage for the bilinguals, mainly because in this dissertation the language of the bilinguals that participated differ largely: one is written and one is not written. It is known that language and cognition walk together and, according to Bialystok et al. (2009) the advantages found in the tasks of executive functions happen because the mechanism used by the bilinguals inhibit one of his languages and use only the most convenient one are similar to other processes of general executive control / Esta tese tem por objetivo principal investigar as diferenças cognitivas, mais especificamente as funções executivas: memória, controle inibitório e atenção, em monolíngues e bilíngues, em dois momentos diferentes. O primeiro momento aconteceu em 2008 quando, para a Dissertação de Mestrado (2010), estudaram-se estas mesmas questões, com crianças na cidade de Arroio do Padre, situada ao sul do Rio Grande do Sul, cuja colonização é predominantemente pomerana e cuja localização, com geografia e relevo distintos, dificulta o acesso aos meios de comunicação mais comuns, o que facilita a preservação até hoje da língua trazida por seus imigrantes pomeranos no final do século XIX. No presente estudo, ampliando a pesquisa antes empreendida, os mesmos sujeitos participantes dos experimentos em 2008 foram contatados e refizeram-nos em 2012, passando a caracterizar a pesquisa como longitudinal. Alargando o escopo da investigação, crianças e adolescentes monolíngues e bilíngues da Escócia, Reino Unido, também participaram dos mesmos experimentos, possibilitando observar se bilíngues que têm, como sua língua-mãe, uma língua ágrafa, como é o caso do pomerano, e aqueles que usam sua L1 para todos os tipos de tarefas diárias incluindo a escrita e a leitura, como é o caso do alemão para os bilíngues escoceses, apresentam diferenças nas funções executivas aqui investigadas. Assim, os objetivos específicos desta tese resumem-se em comparar crianças e adolescentes, brasileiros e escoceses, monolíngues e bilíngues na realização de tarefas de controle executivo geral. Essas tarefas dividem-se em não verbais (Tarefa de Simon) e verbais (Teste de Stroop). Os resultados encontrados nesta tese devem ser divididos em dois grandes grupos, conforme as tarefas propostas e suas peculiaridades. Pode-se dizer que na tarefa de Simon, que é uma tarefa não-verbal, que mede algumas das funções executivas, o controle inibitório e a atenção, os participantes bilíngues parecem ter vantagens sobre os monolíngues investigados. Já quando analisados os resultados do Teste de Stroop, que é uma tarefa que avalia também as funções executivas, controle inibitório e atenção, entretanto é uma tarefa verbal, não se pode afirmar que há vantagem para os bilíngues, principalmente porque nesta tese as línguas dos participantes do grupo bilíngue são muito diferentes, sendo uma ágrafa e outra não. Sabe-se que linguagem e cognição andam juntas e, de acordo com Bialystok et al. (2009), as vantagens encontradas em tarefas de funções executivas em bilíngues se dão porque os mecanismos utilizados para que o bilíngue iniba uma de suas línguas e use apenas a mais conveniente são semelhantes a outros processamentos do controle executivo em geral