Thesis advisor: Lisa Feldman Barrett / The aim of the present study was to examine whether individual differences in Time Insensitivity are related to subjective experiences of emotion and cognitive performance. Sixty-five undergraduates (52% female) completed self-report measures of cognitive flexibility and provided subjective self-reports of emotions following two time pressured cognitive tasks. As predicted, Time Insensitivity was related to self-reported cognitive flexibility, better cognitive performance during a time pressured task, as well as less negative subjective experience in response to these tasks. The results of the present study suggest that Time Insensitivity may have some beneficial outcomes. Limitations and implications for future directions are discussed. / Thesis (BA) — Boston College, 2004. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Psychology. / Discipline: College Honors Program.

This diploma thesis deals with the pupil's solving of learning tasks from biology at grammar schools. Five components of learning tasks were compiled on the basis of the Tollinger taxonomy. Each file tests a different category of Tollinger learning tasks. The main aim of the thesis was to find out which types of learning tasks are preferred by students. The aim of the thesis was based on a questionnaire of pupils as well as on an interview with a biology teacher at the grammar school.

Large-scale scenarios such as search-and-rescue operations, agriculture, warehouse, surveillance, and construction consist of multiple tasks to be performed at the same time. These tasks have non-trivial spatial distributions. Robot swarms are envisioned to be efficient, robust, and flexible for such applications. We model this system such that each robot can service a single task at a time; each task requires a specific number of robots, which we refer to as 'quota'; task allocation is instantaneous; and tasks do not have inter- dependencies. This work focuses on distributing robots to spatially distributed tasks of known quotas in an efficient manner. Centralized solutions which guarantee optimality in terms of distance travelled by the swarm exist. Although potentially scalable, they require non-trivial coordination; could be computationally expensive; and may have poor response time when the number of robots, tasks and task quotas increase. For a swarm to efficiently complete tasks with a short response time, a decentralized approach provides better parallelism and scalability than a centralized one. In this work, we study the performance of a weight-based approach which is enhanced to include spatial aspects. In our approach, the robots share a common table that reports the task locations and quotas. Each robot, according to its relative position with respect to task locations, modifies weights for each task and randomly chooses a task to serve. Weights increase for tasks that are closer and have high quota as opposed to tasks which are far away and have low quota. Tasks with higher weights have a higher probability of being selected. This results in each robot having its own set of weights for all tasks. We introduce a distance- bias parameter, which determines how sensitive the system is to relative robot-task locations over task quotas. We focus on evaluating the distance covered by the swarm, number of inter- task switches, and time required to completely allocate all tasks and study the performance of our approach in several sets of simulated experiments.

Area exploration and information gathering are one of the fundamental problems in mobile robotics. Much of the current research in swarm robotics is aimed at developing practical solutions to this problem. Exploring large environments poses three main challenges. Firstly, there is the problem of limited connectivity among the robots. Secondly, each of the robots has a limited battery life which requires the robots to be recharged each time they are running out of charge. Lastly, the robots have limited memory to store data. In this work, we mainly focus on the memory and energy constraints of the robot swarm. The memory constraint forces the robots to travel to a centralized data collection center called sink, to deposit data each time their memory is full. The energy constraint forces the robots to travel to the charging station called dock to recharge when their battery level is low. However, this navigation plan is inefficient in terms of energy and time. There is additional energy dissipation in depositing data at the centralized sink. Moreover, ample amount of time is spent in traveling from one end of the arena to the sink owing to the memory constraint. The goal is that the robots perform data gathering in the least time possible with the optimal use of energy. Both the energy and time spent while depositing data at the sink act as an additional overhead cost to this goal. In this work, we propose to study an algorithm to tackle this scenario in a decentralized manner. We implement a dynamic task allocation algorithm which accomplishes the goal of exploration with data gathering by assigning roles to robots based on their memory buffer and energy levels. The algorithm assigns two sets of roles, to the entire group of robots, namely: Role A is the data gatherer, a robot which does the task of workspace exploration and data gathering, and Role B is data relayer, a robot which does the task of data transportation from data gatherers to the sink. By this division of labor, the robots dynamically decide which role to choose given the contradicting goals of maximizing data gathering and minimizing energy loss. The choice of a robot to perform the task of data gathering or data relaying is the key problem tackled in this work. We study the performance of the algorithm in terms of task distribution, time spent by the robots on each task and data throughput. We analyze the behavior of the robot swarm by varying the energy constraints, timeout parameter as well as strategies for relayer choice. We also test whether the algorithm is scalable.

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There has been a strong advocacy of Communicative Language Teaching (CLT) in China since the 1980s. One underlying assumption behind this approach is that acquisition is a process which depends on conversational interaction (Wagner-Gough & Hatch, 1975). A specific kind of interaction, meaning negotiation, which “includes routines or exchanges that involve indications of non-understandings and subsequent negotiations of meaning” (Gass & Varonis, 1991, p. 127) has long been considered to be a key factor in L2 development research. From the interactionist perspective, the facilitative role of meaning negotiation in L2 learning is that it provides comprehensible input, and elicits corrective feedback, helps learners to produce comprehensible output, and has the potential to draw learners’ attention to non-target-like aspects of language output. However, recognising the growing role of synchronous computer-medicated communication (SCMC) in language learning, how EFL learners negotiate meaning and whether the claim of the interactionist approach still holds true in this new medium needs further investigation. Moreover, considering the complexity of tasks used in eliciting meaning negotiation and the SCMC involved in negotiating meaning, the exclusively cognitive approach applied by previous studies seems insufficient to explain the meaning negotiation elaborated. For instance, considering the Chinese culture of learning, some Chinese students may be reluctant to produce negotiated interaction. Also, little research has been carried out to investigate the effect of social factors, such as the context and relationship between interlocutors, in generating meaning negotiation. Furthermore, there is little conclusive evidence in previous research regarding the effects of tasks on the quality and quantity of meaning negotiation. This case study investigated 48 EFL students studying mechanical engineering in a Chinese university. Using the variationist perspective on the interaction approach, this study aimed to investigate the features of learners’ negotiated interaction during task-based SCMC, and their similarities and differences with face-to-face negotiated interaction, based on the Varonis and Gass model. Moreover, it also investigates the relationship between task (i.e., task type and task content) and meaning negotiation (i.e., quality and quantity), and the perceived benefits and difficulties of the use of paired task-based SCMC interaction. Also, as previous studies have neglected the individual differences and social factors, the last aim was to investigate how the social and cognitive factors were inextricably intertwined by studying the participants’ perceptions and their actual performances. The main results of the study indicate a low ratio of negotiated turns in paired task-based SCMC interaction due both to linguistic and social factors. Moreover, task did have an influence on the meaning negotiation generated. However, the five-task typology (Pica et al., 1993) applied by most previous studies investigating meaning negotiation cannot fully explain the influence of task on meaning negotiation in peer-peer SCMC context. Apart from the two recurrent features in task definitions, “interactional activity” and “communication goal”, “task complexity” and “task difficulty” (Robinson, 2003) are also influential factors. Overall, this study argues that task, SCMC, the relationship between interlocutors and the learners themselves are all factors which can influence learners’ generation of meaning negotiation. Both personal information and learning contexts have the potential to shape not only the quantity and quality of meaning negotiation but also the attention to the interaction and further influence the production of learners’ language.

Människans förmåga att känna lukter samt känna igen ansikten är två aspekter som är viktiga för människor. I denna studie undersöktes det om obehagliga och behagliga lukter påverkar vilket emotionellt ansikte som kopplas samman med de två olika lukterna. Trettioåtta deltagare deltog i studien och experimentet genomfördes framför en dator i ett test med dot probe paradigmen. Deltagarna fick en lukt placerad under näsan och skattade sedan luktens positivitet/negativitet samt intensitet. Därefter gjordes testet med dot probe och slutligen skattades luktens intensitet ytterligare en gång samt att de skulle matchas ett emotionellt ansikte till lukten. Resultatet visade ingen signifikant skillnad mellan lukterna för dot probe, dock fanns en skillnad mellan skattningarna på lukterna före och efter dot probe.

This thesis aims to explore the role of executive functions in multitasking. Research has shown that severe performance decrements often arise in dual-task performance, also called multitasking, as compared to single task performance. This reflects a limitation in processing temporally overlapping information. Interference between tasks arises due to a bottleneck process limited to processing only one task at a time. It has been proposed that this interference is resolved by executive functions. However, the dual-task paradigm employed in this thesis, Psychological Refractory Period (PRP) paradigm, (Pashler, 1994) is typically investigated in the field of human action performance, and the exact concept of executive functions remains underspecified. However, while underspecified in the area of action performance, executive functions have been investigated in detail in the field of memory research, more specifically in the context of working memory (WM). Therefore, the aim of this thesis was to investigate whether the executive functions in PRP are related to the executive functions as discussed in the context of WM. To test this question, we combined the PRP paradigm with a WM task, creating a complex WM span task. If the executive functions of WM and PRP are indeed related, then an interaction between the two tasks should be evident. Participants were presented with a sequence of letters to remember, followed by a processing block in which they had to perform either a single task or a dual-task, and finally were asked to recall the letters. Results (Chapter 2) showed that recall performance decreased when performing a dual-task as compared to performing a single task. This supports the assumption that PRP dual-tasks demand executive functions of WM. Following this, two other experiments were performed each with a different parametric modulation of the processing demands of the PRP dual task; response order (fixed vs random; Chapter 3) and stimulus onset asynchrony (SOA, short vs long; Chapter 4) of the component tasks. Recall performance was lower after a more difficult dual-task compared to an easier dual-task, which again indicates that demands on executive functions are increased in the dual-task. While previous neuroscientific research indeed showed that dual-tasks as well as WM tasks rely on lateral-prefrontal cortices (LPFC), it remains unknown whether both tasks activate the same areas or different sub-areas of the LPFC. Therefore, this study (Chapter 6) investigated how the neuroanatomical correlates of both dual-task and WM compare to each other. The brain activation for the PRP and WM tasks showed considerable overlap as well as some differentiation. Both tasks activated, among other areas, the inferior frontal junction. With respect to differences, the PRP task activated more the inferior middle frontal gyrus (MFG) whilst the WM component activated more the superior MFG. Thus, results support the assumption that PRP dual-tasks demand the executive functions of WM. This will allow us to inform theoretical models of cognition and to get a better understanding of human cognition. Future studies can build on this in order to create a more consolidated conceptualisation of the relationship between WM and multitasking.

Background: Surgical checklists are in use as means to reduce errors for safer surgery. Checklists are infrequently applied during procedures and have been limited to lists of procedural steps as aid memoires. Aims: We aimed to formulate a performance based checklist and to study its effect on the surgical task performance of novice surgeons when applied during both, routine knot tying and simulated emergency laparoscopic tasks. We also aimed to study the effect of the performance based intra-procedural checklist in clinical environments during elective laparoscopic procedures as a way of error reduction mechanism and improvement of patient safety. Methods: The study was conducted in two settings, lab-based and clinical-based environments. The lab-based study was conducted during both routine and emergency tasks. Lab-based study- routine task: Twenty novices were randomised into two equal groups, those receiving paper feedback (control group), and those receiving paper feedback and the checklist that was applied at 20 seconds intervals (checklist group). The task involved performing laparoscopic double knots which were repeated over 5 separate stages. Human reliability assessment technique was used for error analysis on unedited video recordings of the tasks. Endpoints included number of errors, error probability (number of errors/number of knots), error types and number of completed knots. Non-parametric statistics were used for data analysis. Lab-based- emergency task: Thirty consented laparoscopic novices were exposed unexpectedly to a bleeding vessel in a laparoscopic virtual reality simulator as an emergency surgical scenario. The task consisted of using laparoscopic clips to achieve haemostasis. Subjects were randomly allocated into 2 equal groups; those using the checklist (checklist group) and those without (control group). The checklist was applied by the trainees in the checklist group at 20 seconds intervals. The surgical performance was computed on eight predetermined technical factors. Clinical-based study: Surgical trainees in the general surgery at Tayside NHS were included in this study and required the attendance of a trainer during the procedure as per routine practice. Record year of trainees and previous experience on laparoscopic cholecystectomy were noted. Two elective laparoscopic cholecystectomies for each trainee were video-recorded without the use of the checklist, directly followed by 2 further operations after the introduction of the checklist. The unedited videos were analysed for error detection using human reliability analysis technique. Total number of errors per time during each procedure, total number of errors per number of instrument movements, total number of instrument movements per time and number of trainer intervention while per time were noted as assessment points. Results: Lab-based- routine task: 2341 errors were detected in 141 tasks, 408 subtasks and 2249 steps during the 5 stages. During the first stage, the errors were not significantly different between groups. The checklist group committed significantly fewer errors as compared to the control group during all the later 4 stages (p < 0.01). The checklist group had an enhanced learning curve as the last 4 stages showed significant fewer errors compared to the first stage (p < 0.05), while the control group showed no improvement. Error probability was significantly higher in the control group compared to the checklist group: median [IQR] 32.6 [25.89] vs 11.7 [10.72] (p < 0.01). Individual error types during each step of the laparoscopic task were identified. The checklist group performed better with fewer errors for all the error types. While, there was no significant difference in each of 'the lack of supination', 'tissue bite' and 'out of vision'; the differences in all the rest of error types were highly statistically significant (p < 0.01). Number of completed knots was not statistically different between the 2 groups. Lab-based- emergency task: The checklist group performed significantly better in 6 out of 8 technical factors when compared to the control group median [IQR]: Right instrument path length (m) 1.44 [1.22] vs 2.06 [1.70] (p= 0.029), and right instrument angular path (degree) 312.10 [269.44] vs 541.80 [455.16] (p= 0.014), left instrument path length (m) 1.20 [0.60] vs 2.08 [2.02] (p= 0.004), left instrument angular path (degree) 277.62 [132.11] vs 385.88 [428.42] (p= 0.017). The checklist group committed significantly fewer number of errors in the number of badly placed clips (p= 0.035) and number of dropped clips (p= 0.012). Although statistically not significant, total blood loss (lit) decreased in the checklist group from 0.83 [1.23] to 0.78 [0.28] (p= 0.724), and total time (sec) from 186.51 [145.69] to 125.14 [101.46] (p=0.165). Clinical-based study: Participants performed statistically better with fewer number of errors per time with the application of the checklist compared to when no checklist was used respectively: Median [IQR] total number of errors 1.51 [0.80] vs 3.84 [1.42] (p=0.002), consequential errors 0.20 [0.12] vs 0.45 [0.42] (P=0.005), inconsequential errors 1.32 [0.75] vs 3.27 [1.48] (p=0.006) and total number of errors per number of instrument movements 0.16 [0.04] vs 0.29 [0.16] (p= 0.003). With the introduction of the checklist, the number of interventions by the trainer per time decreased from 2.79 [1.85] to 0.43 [1.208] (p=0.003) and the number of instrument movements per time decreased from 11.90 [5.34] to 10.38 [5.16] (p=0.04). Conclusions: We have developed standardised checklists to be applied during elective and emergency laparoscopic tasks. The performance based self-administered intra-procedural checklist had a significant accelerating effect on the acquisition of technical skills when applied by novices during a standardised laparoscopic lab-based routine task and improved the task performance during a simulated laparoscopic emergency scenario. The checklist enhanced the performance of surgical trainees and decreased the number of interventions of the trainer during laparoscopic cholecystectomy.

Real life decision-making depends on a complex interplay between cognitive and emotion-based processes. Damasio (1994) developed the Somatic Marker Hypothesis (SMH) arguing that emotion-based processes guide decision-making by directing individuals towards alternatives that have been previously ‘marked’ as positive or guide them away from the negative options. The primarily used test-bed of the emotion-based learning is Iowa Gambling Task (IGT, Bechara, Damasio, Damasio, & Anderson, 1994). The SMH makes three assumptions about the IGT behaviour: (a) somatic markers have a negative connotation and bias decision-making covertly in the absence of explicit knowledge, (b) there is a limited role for cognitive procesesing during IGT performance, especially during the initial stages of the task, and (c) anticipatory somatic markers guide decision-choices away from the bad options as participants are able to anticipate the good and the bad options. This thesis tested the SMH using a combination of psychophysiological methods (Eye-tracking, Pupillometry, Heart Rate and Blood Pressure measurements), behavioural measurements and psychometric measures of individual differences in combination with the IGT. The systematic review, meta-analyses and the experiments described in this Thesis explored the validity of these assumptions and found that they are not accurately manifested in behaviour during IGT performance. A novel methodology not previously employed was used to capture somatic markers through pupillary responses. Explicit learning was also assessed by the eye-tracking methodology in testing IGT performance in normal conditions and under stress. The results from the first two experiments indicated that explicit processing and knowledge about the task are more critical factors during the early stages of the game than previously suggested. Although there were some indicators of the existence of somatic markers, it was found that cognitive reflection, conscious awareness and increased cognitive processing occurred early in the game and guided behaviour on IGT. The results from the final experiment revealed that IGT performance in healthy individuals is not always optimal; stress levels impaired performance whereby a lack of, or insufficient cognitive processing early in the game may create a somatic signal that interferes with IGT performance. Furthermore, attentional processing, cognitive reflection and conscious awareness can be disrupted by stress resulting in non-optimal decision-making strategies that consequently interfere with performance on the IGT. Taken together, these results challenge the basic premises of the SMH and could be best explained within the dual-process framework (e.g., Brevers, Bechara, Cleeremans, & Noel, 2013). If somatic markers do not play a significant role in learning IGT than the task needs to be re-evaluated and caution is warranted when the IGT is used as a diagnostic tool to measure decision-making deficits in clinical populations.