The study of executive functions in disorders of inhibitory control dysfunction: Autism spectrum disorder and neurofibromatosis type 1

Dissertação de mestrado apresentada no Ispa – Instituto Universitário para obtenção de grau de Mestre na especialidade de Psicologia ClínicaABSTRACT: Aim: Previous literature indicates that executive functioning is altered in both Autism Spectrum Disorder (ASD) and Neurofibromatosis Type 1 (NF), having an impact on response inhibition although it is not yet established to what extent. The primary aim of this dissertation is to study executive functions (EFs), with focus on response inhibition, in disorders with inhibitory dysfunction (ASD and NF1), allowing us to understand phenotype specificities. Method: A total of 60 participants, forming two experimental groups (ASD vs. NF1) and their respective control groups (CTASD vs. CTNF1) participated in the study. Participants were matched in age, sex and handedness with their respective control groups. A battery of 4 CANTAB tests, Trail Making (A and B) and Stroop tests were administered to fully evaluate EF in our groups. Results: Significant differences were found in the ASD group which take longer to react (latency is higher) to achieve a good performance (not making errors) in comparison to controls. In the NF1 vs. CTNF1 comparison, there were no significant differences, except on the screening test, where NF1 were faster than CTNF1, although this did not have a negative influence on performance. Conclusion: These findings reveal different patterns of performance in both ASD and NF1 groups although they predominantly indicate spared EF as they were measured in the current study. Further exploration of the results and practical implications are discussed, highlighting the need to conduct large-scale studies in adults using more ecological tasks that better represent the daily-life experiences of the participants.RESUMO: Objetivo: A literatura sugere que o funcionamento executivo está alterado na Perturbação do Espetro do Autismo (PEA) e na Neurofibromatose Tipo 1 (NF1), tendo um impacto na resposta inibitória, embora ainda não seja claro em que magnitude. O principal objetivo desta dissertação consiste em estudar as funções executivas (FEs), com incidência na inibição de resposta, em perturbações com disfunção inibitória, (PEA e NF1) permitindo-nos compreender as suas especificidades. Método: Um total de 60 participantes, formando dois grupos experimentais (PEA vs. NF1) e os seus respetivos grupos de controlo (CTPEA vs. CTNF1) participaram neste estudo. Os participantes tinham a mesma idade, lateralidade e sexo que os seus respetivos controlos. Foram administrados 4 testes da CANTAB, Trail Making Test (A e B) e o teste Stroop, a fim de avaliar as FEs nos grupos. Resultados: Foram encontradas diferenças significativas no grupo PEA que demorou mais tempo a reagir (maior latência) para alcançar um bom desempenho (sem erros) em comparação com o seu grupo de controlo. Na comparação NF1 vs. CTNF1, não houve diferenças significativas, exceto no teste de rastreio, onde NF1 foi mais rápido do que CTNF1, embora isto não tenha tido uma influência negativa no desempenho. Conclusão: Estes resultados revelam padrões diferentes de desempenho dos grupos PEA e NF1, embora indiquem FEs preservadas, tal como foram medidas neste estudo. São discutidos aprofundadamente os resultados e as implicações práticas, destacando-se a necessidade de estudos futuros, em adultos, utilizando tarefas mais ecológicas que representem melhor as experiências da vida quotidiana dos participantes

Queuing Network Modeling of Human Multitask Performance and its Application to Usability Testing of In-Vehicle Infotainment Systems.

Human performance of a primary continuous task (e.g., steering a vehicle) and a secondary discrete task (e.g., tuning radio stations) simultaneously is a common scenario in many domains. It is of great importance to have a good understanding of the mechanisms of human multitasking behavior in order to design the task environments and user interfaces (UIs) that facilitate human performance and minimize potential safety hazards. In this dissertation I investigated and modeled human multitask performance with a vehicle-steering task and several typical in-vehicle secondary tasks. Two experiments were conducted to investigate how various display designs and control modules affect the driver's eye glance behavior and performance. A computational model based on the cognitive architecture of Queuing Network-Model Human Processor (QN-MHP) was built to account for the experiment findings. In contrast to most existing studies that focus on visual search in single task situations, this dissertation employed experimental work that investigates visual search in multitask situations. A modeling mechanism for flexible task activation (rather than strict serial activations) was developed to allow the activation of a task component to be based on the completion status of other task components. A task switching scheme was built to model the time-sharing nature of multitasking. These extensions offer new theoretical insights into visual search in multitask situations and enable the model to simulate parallel processing both within one task and among multiple tasks. The validation results show that the model could account for the observed performance differences from the empirical data. Based on this model, a computer-aided engineering toolkit was developed that allows the UI designers to make quantitative prediction of the usability of design concepts and prototypes. Scientifically, the results of this dissertation research offer additional insights into the mechanisms of human multitask performance. From the engineering application and practical value perspective, the new modeling mechanism and the new toolkit have advantages over the traditional usability testing methods with human subjects by enabling the UI designers to explore a larger design space and address usability issues at the early design stages with lower cost both in time and manpower.PHDIndustrial and Operations EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113590/1/fredfeng_1.pd

Do you listen to music while studying? A portrait of how people use music to optimize their cognitive performance

Contains fulltext : 239174.pdf (Publisher’s version ) (Open Access)The effect of background music (BGM) on cognitive task performance is a popular topic. However, the evidence is not converging: experimental studies show mixed results depending on the task, the type of music used and individual characteristics. Here, we explored how people use BGM while optimally performing various cognitive tasks in everyday life, such as reading, writing, memorizing, and critical thinking. Specifically, the frequency of BGM usage, preferred music types, beliefs about the scientific evidence on BGM, and individual characteristics, such as age, extraversion and musical background were investigated. Although the results confirmed highly diverse strategies among individuals regarding when, how often, why and what type of BGM is used, we found several general tendencies: people tend to use less BGM when engaged in more difficult tasks, they become less critical about the type of BGM when engaged in easier tasks, and there is a negative correlation between the frequency of BGM and age, indicating that younger generations tend to use more BGM than older adults. The current and previous evidence are discussed in light of existing theories. Altogether, this study identifies essential variables to consider in future research and further forwards a theory-driven perspective in the field.11 p

Switch rates vary due to expected payoff but not due to individual risk tendency.

When switching between different tasks, the initiation of task switches may depend on task characteristics (difficulty, salient cues, etc.) or reasons within the person performing the task (decisions, behavioral variability, etc.). The reasons for variance in switching strategies, especially in paradigms where participants are free to choose the order of tasks and the amount of switching between tasks, are not well researched. In this study, we follow up the recent discussion that variance in switching strategies might be partly explained by the characteristics of the person fulfilling the task. We examined whether risk tendency and impulsiveness differentiate individuals in their response (i.e., switch rates and time spent on tasks) to different task characteristics on a tracking-while-typing paradigm. In detail, we manipulated two aspects of loss prospect (i.e., "payoff" as the amount of points that could be lost when tracking was unattended for too long, and "cursor speed" determining the likelihood of such a loss occurring). To account for between-subject variance and within-subject variability in the data, we employed linear mixed effect analyses following the model selection procedure (Bates, Kliegl, et al., 2015). Besides, we tested whether risk tendency can be transformed into a decision parameter which could predict switching strategies when being computationally modelled. We transferred decision parameters from the Decision Field Theory to model "switching thresholds" for each individual. Results show that neither risk tendency nor impulsiveness explain between-subject variance in the paradigm, nonetheless linear mixed-effects models confirmed that within-subject variability plays a significant role for interpreting dual-task data. Our computational model yielded a good model fit, suggesting that the use of a decision threshold parameter for switching may serve as an alternative means to classify different strategies in task switching. [Abstract copyright: Copyright © 2022. Published by Elsevier B.V.

Are Individual Differences in Media Multitasking Habits Associated with Changes in Brain Activation: An ERP Investigation of Multitasking and Cognitive Control

As the number of mobile phone users grows, understanding the impact of multiple streams of media on media multitasking and related neural correlates is especially pertinent. This research aims to understand the association between media multitasking tendencies on the neural correlates underlying cognitive control using event-related potentials (ERPs). Specifically, we were interested in the N2 and P3, ERPs that measure neural activation underlying aspects of cognitive control. Based on the literature, we predicted that participants who have high media multitasking scores would show more negative N2 activation and more positive P3 activation than their low media multitasking counterparts during an AX-CPT task, indicating less efficient neural processing. However, we did not find the expected pattern of results. It is possible that reactive and proactive control are not related to digital media multitasking or it may be that some potential design issues impacted our results. The current paper will explore these issues

Age-Based Differences in Task Switching Are Moderated by Executive Control Demands

OBJECTIVES: Recent work has identified different aspects of executive function that may underlie cognitive changes associated with age. The current study used a multifactorial design to investigate age sensitivity in the ability to shift between different task sets and the interaction of this ability with several specific aspects of executive control. METHOD: A large, well-characterized sample of younger (n = 40) and clinically healthy older (n = 51) adults completed a task switching paradigm in which 3 aspects of executive control were manipulated between subjects: a) sensorimotor demand (the number of distinct stimulus-response options); b) stimulus-level interference (i.e., flanker effects); and c) updating/monitoring (the frequency of task switches). RESULTS: Unique age-related deficits were observed for different aspects of local task switching performance costs and updating/monitoring, but not for interference. Sensorimotor demand was also an important additional factor that interacted with task switching performance. DISCUSSION: Our findings suggest that task switching, coupled with infrequent and unexpected transitions from one task set to another, in the context of high motoric demands, is particularly difficult for older adults