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De-mixing Decision Representations in Rodent DMPFC to Investigate Strategy Change During Delay Discounting
No full textSeveral pathological disorders are characterized by maladaptive decision-making (Dalley & Robbins, 2017). Decision-making tasks, such as Delay Discounting (DD), are used to assess the behavioral manifestations of maladaptive decision-making in both clinical and preclinical settings (de Wit, Flory, Acheson, Mccloskey, & Manuck, 2007). DD measures cognitive impulsivity and broadly refers to the inability to delay gratification (Hamilton et al., 2015). How decisions are made in tasks that measure DD can be understood by assessing patterns of behavior that are observable in the sequences of choices or the statistics that accompany each choice (e.g. response latency). These measures have led to insights that suggest strategies that are used by the agent to facilitate the decision (Linsenbardt, Smoker, Janetsian-Fritz, & Lapish, 2016).The current set of analyses aims to use individual trial data to identify the neural underpinnings associated with strategy transition during DD. A greater understanding of how strategy change occurs at a neural level will be useful for developing cognitive and behavioral strategies aimed at reducing impulsive choice. The rat dorso-medial prefrontal cortex (dmPFC) has been implicated as an important brain region for recognizing the need to change strategy during DD (Powell & Redish, 2016).Using advanced statistical techniques, such as demixed principal component analysis (dPCA), we can then begin to understand how decision representations evolve over the decisionmaking process to impact behaviors such as strategy change. This study was the first known attempt at using dPCA applied to individual sessions to accurately model how decision representations evolve across individual trials. Evidence exists that representations follow a breakdown and remapping at the individual trial level (Karlsson, Tervo, & Karpova, 2012; Powell & Redish, 2016). Furthermore, these representational changes across individual trials have previously been proposed to act as a signal to change strategies (Powell & Redish, 2016). This study aimed to test the hypothesis that a ‘breakdown’ followed by a ‘remapping’ of the decision representation would act as a signal to change strategy that is observable in the behavior of the animal.To investigate the relationship between trials surrounding the breakdown and/or subsequent remapping of the decision representation and trials surrounding strategy changes, sequences of trials surrounding the breakdown and/or remappingwere compared to sequences of trials surrounding the strategy-change trial. Strategy types consisted of either exploiting the immediate lever (IM-Exploit), delay lever (DEL-Exploit), or exploring between the two lever options (Explore). Contrary to the hypothesis, an overall relationship between breakdown and remapping trial sequences were not associated with change-trial sequences. In partial support of the hypothesis however, at the 4-sec delay when the subjective value of the immediate reward was high, a relationship between breakdown sequence and strategy change sequence was detected for when the animal was exploiting the delay lever (e.g. DEL-Exploit strategy). This result suggests that a breakdown in decision representation may act as a signal to prompt strategy change under certain contexts.One notable finding of this study was that the decision representation was much more robust at the 4-sec delay compared to the 8-sec delay, suggesting that decisions at the 4-sec delay contain more context that differentiate the two choice options (immediate or delay). In other words, the encoding of the two choice options was more dissociable at the 4-sec delay compared to the 8-sec delay, which was quantified by measuring the average distance between the two representations (immediate and delay) on a given trial. Given that Wistar rats are equally likely to choose between the immediate and delay choice alternatives at the 8-sec delay (Linsenbardt et al., 2016), this finding provides further support for current prevalent theories of how animals use a cognitive search process to mentally imagine choice alternatives during deliberation. If context which differentiates choice options at the 8-sec delay is less dissociable, it is likely that the cognitive search process would be equally likely to find either choice option. If the choice options are equally likely to be found, it would be assumed that the choice alternatives would also be equally likely to be chosen, which is what has been observed in Wistar rats at the 8-sec delay
Critical Zone Calculation for Automated Vehicles Using Model Predictive Control
No full textThis thesis studies critical zones of automated vehicles. The goal is for the automated vehicle to complete a car-following or lane change maneuver without collision. For instance, the automated vehicle should be able to indicate its interest in changing lanes and plan how the maneuver will occur by using model predictive control theory, in addition to the autonomous vehicle toolbox in Matlab. A test bench (that includes a scenario creator, motion logic and planner, sensors, and radars) is created and used to calculate the parameters of a critical zone. After a trajectory has been planned, the automated vehicle then attempts the car following or lane change while constantly ensuring its safety to continue on this path. If at any point, the lead vehicle brakes or a trailing vehicle accelerates, the automated vehicle makes the decision to either brake, accelerate, or abandon the lane change
Implementation of Enhanced Probe Data (CANBUS) for Tactical Workzone and Winter Operations Management
Get PDFFor over a decade, segment-based probe data has been extensively used by transportation stakeholders for monitoring mobility on Indiana roadways. However, enhanced probe data from connected vehicles includes a richer dataset that can provide more detailed real-time and after-action reviews. This enhanced data includes detailed vehicle trajectories, at 3s resolution, and “event data.” This event data is near real-time and includes hard-braking events, hard-acceleration events, weather-related data, including wiper activations and some seat belt usage data. This project developed a set of methodologies and resulting visualizations that enables the use of emerging connected vehicle data in operational decision-making on work zone management and winter operations activities. Each month approximately 13 billion connected vehicle records are ingested for Indiana. During peak periods, approximately 625,000 records per minute are ingested. Without substantial processing, this large data set is “data-rich, information-poor.” This study developed techniques to rapidly assign relevant data to interstate segments so that visual graphics could be efficiently generated. This provided the ability for both real-time monitoring as well as after action assessment to identify opportunities to improve both work zone operations and winter operation activities. The summaries derived from these datasets have helped promote effective actionable dialog among agencies, contractors, and public safety colleagues towards the overarching goal of improving interstate safety and mobility
Student Information Use During the COVID-19 Pandemic
Get PDFSince early 2020, life for students has changed tremendously. It has been a time of stress, turmoil, and trauma for students. Researchers from a large Midwestern university wanted to determine how student information use has changed during the COVID-19 pandemic. This paper examines the results of a mixed-methods study undertaken in 2021 using surveys and follow-up focus groups to determine if and how student information use has changed. To answer this, we explored student use of news sources, social media sources, political affiliations, and information responses, coupled with to what extent these factors demonstrate or impact potential changes in information use. We also addressed changes in the frequency of use, as well as the types of resources consulted, pertaining to information use of traditional and social media sources
U.S. Government Information Resources for Accountability on U.S. Assistance to Ukraine
No full textProvides detailed coverage of U.S. Government information resources documenting accountability for U.S. civilian and military assistance to Ukraine. Includes U.S. laws, agencies involved in U.S. arms export policy, Defense Department resources and data, Defense Dept. Inspector General reports, Government Accountability Office reports, congressional committee hearings, a letter from a congressional committee to the Secretaries of Defense and State and U.S. Agency for International Development administrator, congressional debate, and congressional recorded votes
Project Evolution: From Tactical Urbanism to Permanent Infrastructure
Get PDFThe public has lots of ideas for traffic calming projects, but it can be quite the undertaking to determine what ideas are feasible, have serious community backing, and are adaptable. Learn how the City of Fort Wayne has partnered with community organizations on quick-build projects that have evolved into long-term and permanent changes. Participants will learn of Fort Wayne’s program guidelines for community-led demonstration projects, such as the types of projects, locations, materials used, and funding resources
Are Professional Societies Worth It?
Get PDFAttendees will discuss the benefits of joining a professional organization. Learn how to boost your career as a young professional, expand your professional network, and stay up to date on the latest trends
Unique pavement maintenance solutions for agencies facing a limited workforce
Get PDFCome explore cutting-edge pavement maintenance materials and applications that agencies can implement with smaller crews and less equipment. We discuss how this new technology requires less labor, can extend pavement life, will reduce worker exposure to traffic, and increase ride quality. Join us as we explore where and how these new materials can be applied and investigate how antiquated pavement maintenance repair methods require a high redundancy of various treatments, which leads to higher mobilization, labor, and material costs
Traffic Signal Preemption Near Active Railroad Crossings Revisited
Get PDFThis session is an updated version of “Traffic Signal Advance Pre-emption Design within 200’ of Active Railroad Crossings,”—a 2012 Purdue Road School presentation. The issue of Traffic Signal Preemption has changed, positively and negatively, for INDOT and the railroads. A review of the updated traffic signal preemption material will benefit designers, operations staff, and local agencies
How to Prepare Meaningful Crash Analysis
Get PDFMany people outside of traffic engineering are required to conduct a crash history analysis as part of their scoping efforts for non-safety funded projects. Some engineers may not have much experience working with crash data or may not know how best to manipulate it to arrive at meaningful results. Using real-world examples, this presentation will walk through each step in requesting, filtering, diagramming, and interpreting crash data