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Tactile Cues in the Control of Action: An Emphasis on Movement InitiationDiamond, Jonathan 14 January 2010 (has links)
The ability to detect a tactile stimulus during movement is markedly decreased (e.g., tactile gating), yet it is unknown whether the stimulus influences motor output. In the present study, participants moved a mechanical slider as quickly and as accurately as possible to a target. Participants received low-level electrical stimulation on the index finger of the reaching limb at various offsets relative to movement initiation. Participants reported whether they perceived the tactile cue. It was hypothesized that the detection of the stimulus would be reduced and the stimulus would influence motor output. First, a typical time course and magnitude of sensory gating was found, supporting previous observations (e.g., Chapman & Beauchamp, 2006). Second, no influence of the stimulation on motor output was observed. It was concluded that the detection of tactile cues during a goal-directed reaching task is attenuated and this stimulation does not influence motor output.
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Tactile Cues in the Control of Action: An Emphasis on Movement InitiationDiamond, Jonathan 14 January 2010 (has links)
The ability to detect a tactile stimulus during movement is markedly decreased (e.g., tactile gating), yet it is unknown whether the stimulus influences motor output. In the present study, participants moved a mechanical slider as quickly and as accurately as possible to a target. Participants received low-level electrical stimulation on the index finger of the reaching limb at various offsets relative to movement initiation. Participants reported whether they perceived the tactile cue. It was hypothesized that the detection of the stimulus would be reduced and the stimulus would influence motor output. First, a typical time course and magnitude of sensory gating was found, supporting previous observations (e.g., Chapman & Beauchamp, 2006). Second, no influence of the stimulation on motor output was observed. It was concluded that the detection of tactile cues during a goal-directed reaching task is attenuated and this stimulation does not influence motor output.
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Impairments in higher cognitive functions following frontal lobe lesions in manSwain, Sharon Ann January 1996 (has links)
No description available.
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On the Analysis of Mouse BehaviorMurdaugh, Laura Bethany 16 January 2024 (has links)
Accurate and high throughput methods of measuring animal behavior are critical for many branches of neuroscience, allowing for mechanistic studies and preclinical drug testing. Methodological limitations contribute to narrow investigations, which may overlook the interplay between distinct but related behaviors, like affective behaviors and executive function (EF). To prevent such oversight, researchers can perform test batteries, or multiple assessments in one study. However, test batteries often exclude cognitive behaviors due to their lengthy testing period. This dissertation first reviews current evidence related to the investigation and relation of affective, pain-like, and operant behaviors in rodent models. Then, I demonstrate the use of traditional and novel test batteries to investigate these behavioral changes in multiple mouse models.
First, I investigated affective and pain-like behavior in mice lacking Nape-pld, a key enzyme that synthesizes lipid mediators which activate receptors in the endocannabinoid system. I found that these mice displayed reduced sucrose preference, but otherwise normal anxiety- and depression-like behavior, and had baseline differences in thermal nociception and inflammation response. Then, I investigated the affective, pain-like, and operant effects of chronic vapor exposure (CVE) to vehicle or nicotine (NIC). Regardless of NIC content, acute abstinence from CVE increased mechanical sensitivity and self-grooming, while chronic abstinence from NIC CVE resulted in motor stimulation. Other traditional anxiety- and depression-like behaviors were unchanged by CVE. In an operant test battery, acute abstinence from NIC CVE impaired acquisition, decreased sucrose motivation, and impaired the response to aversive rewards. Finally, I developed a protocol for the high throughput analysis of six operant tests which can be completed in as few as nineteen sessions, significantly fewer sessions than traditional operant tests. This battery investigates multiple aspects of goal-directed behavior and EF including operant acquisition, cognitive flexibility, reward devaluation, motivation via response to increased instrumental effort, cue devaluation or the extinction of learned behavior, and reacquisition. I validated several of these tests by demonstrating that lesions to specific subregions of the orbitofrontal cortex impaired cognitive flexibility and altered response to instrumental effort as observed in traditional operant tests. I then used this battery to investigate the effects of the P129T mutation, which results in a mutated version of the Fatty Acid Amide Hydrolase (FAAH) enzyme that is associated with addiction, in male and female mice. Knock-in animals displayed reduced activity in response to increasing instrumental effort, and reduced activity on the first day of an extinction test. Then, to encourage others to use this new operant battery I outlined how to efficiently collect data, shared a database for customizable analysis, and described common issues and how to solve them. This protocol has potential implications for many aspects of neuroscience including the investigation of novel therapeutics and the neural circuitry underlying behaviors.
Together, the information in this dissertation demonstrates the utility of multi-faceted behavioral assays and the combination of traditional and novel approaches to collect more comprehensive behavioral data, which will allow researchers to better investigate neural circuitry underlying behaviors or the behavioral changes associated with novel therapeutics. / Doctor of Philosophy / By measuring animal behavior researchers can gain insight into how specific brain regions interact to influence choice and action. Limitations in testing methods mean that researchers may fail to investigate the relationship between distinct aspects of behavior, like the influence of emotional state or pain on cognition. To prevent such oversight researchers can perform a test battery, a specific series of multiple tests that measures several different aspects of behavior. Traditional test batteries often overlook cognitive or operant (learning to perform an action for reward) behaviors due to time constraints, which limits their translational potential. This dissertation provides a brief overview of the ways that researchers investigate affective (emotional), pain-like (physical discomfort), and goal-directed behaviors. It further has a broad focus on mouse models related to addiction or the endocannabinoid system (ECS), which is shown to play a role in mood, pain (e.g., perception, relief, and inflammation), and cognition. Using a traditional test battery, we demonstrate that mice lacking a key enzyme in the ECS have altered responses to sugar, heat, and inflammation, but display otherwise normal performance in anxiety-, depression-, and pain-like tests. Next, we used a combined traditional and operant battery to investigate the effects of chronic vapor exposure (CVE) and nicotine in mice. We found that regardless of nicotine content, acute abstinence from CVE increased physical sensitivity and self-grooming but spared other anxiety- and depression-like behaviors. Acute abstinence from nicotine CVE resulted in motor stimulation, impaired operant learning, lower motivation for sucrose reward, and an impaired ability to withhold responding when presented with a bitter reward. Finally, I outline a novel operant test battery that addresses the limitations of current operant chamber- or place-based batteries. Using this battery, I first demonstrate that it captures similar behavioral changes to those seen in traditional operant chambers. Then, I demonstrate that mice containing an ECS mutation associated with problem drug use in humans display less motivation for food reward in response to increased effort, and more quickly inhibit a learned behavior when reward delivery is interrupted. I also found that in response to increased effort for reward or bitter rewards, male mice are more likely to alter their behavioral strategy. To encourage others to use this new operant battery I outlined how to efficiently collect data, shared a database for customizable analysis, and described common issues and how to solve them. This protocol has the potential to improve upon traditional tasks while opening cognitive research to more scientists. This has implications for many fields of neuroscience, especially the investigation of novel therapeutics and investigation of the neural circuitry underlying various disorders.
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The Influence of Money on Goal Pursuit and Decision-Making: Understanding Money's Unique Impact on Goal PursuitMoran, Nora 07 May 2015 (has links)
Previous research suggests that activating concepts of money and wealth can increase motivation to achieve personal goals. In this dissertation, I investigate how money affects pursuit of important personal goals, and how this motivation may be affected by goal attainability. In eight studies, I show that priming concepts of money and wealth leads individuals to pursue important personal goals to a greater degree than control groups, but only when a goal is more attainable. In contrast, when a goal is less attainable, those primed with money will be less likely to work towards goals relative to control groups. Furthermore, I examine why money may have a detrimental effect on motivation when individuals are faced with less attainable but important goals, and argue those primed with money become more concerned with maintaining a sense of efficacy, and thus disengage from pursuit when success is less certain. Thus, this research identifies the needs made salient by activating money-"validating one's abilities. Finally, I show the relevance of these findings for consumer behavior, and discuss the additional implications of this work, as well as future research directions. / Ph. D.
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Moving & feeling : the modulation of tactile perception during goal-directed movements : evidence from reaching, grasping, catching, & throwingJuravle, Georgiana January 2012 (has links)
This thesis focuses on tactile perception and aims at a comprehensive analysis of its characteristics over the time-course of various goal-directed movements. Tactile perception is assessed by means of discrimination and detection paradigms, as well as event-related potentials (ERPs). The main question investigated throughout the thesis is: ‘What changes in tactile perception, if any, take place over the time course of a goal-directed movement?’ In Chapter 2, the mechanisms related to such identified changes are examined: a facilitatory one – attention, and an inhibitory one – suppression. The experiment in Chapter 3 tests, at a brain level, amongst several explanations of the experimental results outlined in Chapter 2: timing-based, effector-based, and modality-based attentional/suppressive influences. In Chapter 4, other naturalistic movements are investigated (i.e., the movements involved in juggling and throwing/catching a basketball). The results indicate a lack of facilitation in the processing of tactile information during the preparatory phase of the movement. Furthermore, differential changes are identified in tactile perception over the execution phase of the movement: At a behavioural level, tactile sensitivity significantly declines over the execution phase of the movement (though the detection of incoming tactile stimulation is enhanced), while at a neuronal level the same period exhibits significantly enhanced responses to somatosensory stimulation. The experiments reported here thus bring evidence in favour of a dissociation between detecting and discriminating what is felt while moving. These results suggest that the quality of what is felt while moving may not be important for movement and, at the same time, that different pathways in the brain may be responsible for detecting and discriminating what is felt over the time course of a goal-directed movement. Based on these findings, in Chapter 5, the implications of these results are discussed and directions for further research are outlined.
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Moving Evidence into Practice: Early Sepsis Identification and Timely Intervention in the Emergency Department (Project Code Sepsis)Macalintal, Jonjon 01 January 2016 (has links)
Sepsis is the leading cause of death among hospitalized patients in the United States, is responsible for more than 200,000 deaths annually, and has as high as a 50% mortality rate. Sepsis requires prompt identification so that early goal-directed therapy can be instituted to lead to better outcomes. The purpose of this quality improvement project was to determine if implementing an evidence-based identification and intervention program, Project Code Sepsis, in the emergency department can increase the number of patients who receive antibiotics within the first hour of triage and decrease the length of hospital stay. Specifically, the primary project goals were: (a) to administer initial antibiotic treatments within 1 hour of triage to more than 75% of patients, and (b) to reduce length of hospital stay to an average of less than 7 days. The project was developed from the Donabedian Healthcare Quality Triad and guided by the Six Sigma DMAIC method. A total of 306 patients were included in this project conducted from May to October 2015. The sepsis-screening tool was fully implemented during August when more than 75% of patients received their initial antibiotic within one hour of triage time. However, this accomplishment was not sustained during the next two months. Interestingly, August was also the month with the highest length of hospital stay (7.49 days) among sepsis patients. This quality improvement project did not show that the provision of antibiotic therapy within the first hour of triage time decreases the length of hospital stay among sepsis patients. Multiple factors including administration of intravenous fluids and vasopressors for hypotension, nurse and physician experiences, patient acuity, and local sepsis bacteria profile should be considered together in future studies and quality improvement projects.
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Goal pursuit is more than planning: the moderating role of regulatory fitTam, Wing Yin Leona 30 October 2006 (has links)
Research indicates that planning helps consumers in their goal pursuit, but little is
known about how and when such beneficial effects change with regulatory fit â fit
between consumersâ regulatory orientation and goal pursuit means. Results of three
studies show that 1) the benefits of forming implementation intentions, or planning
details such as when, where, how, and how long to perform goal-directed actions and
attain consumer goals are stronger in regulatory nonfit situations (study 1), and 2)
implementation intentions can be viewed as goal pursuit means and be part of the
regulatory fit formulation to show the âÂÂvalue from fitâ effect on instrumental behavior
and goal attainment (studies 2 and 3). Specifically, study 1 showed that consumers in
regulatory nonfit situations are more likely to perform instrumental behavior and have
higher goal attainment by forming implementation intentions than consumers in
regulatory fit situations. This research also provides empirical evidence of the notion of
âÂÂvalue from fitâ to the regulatory fit literature, that is, the mediating role of motivation
intensity in the regulatory fit-instrumental behavior and regulatory fit-goal attainment
linkages in studies 2 and 3.
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Impacts of goal setting on engagement and rehabilitation outcomes following aquired brain injury : A systematic reviewPaloniemi, Katri January 2018 (has links)
Purpose: To appraise and synthesize the available evidence from previous systematic reviews concerning the impacts of goal setting on engagement in the rehabilitation process and on outcomes of participation and occupational performance for individuals with acquired brain injury (ABI). Material and method: Systematic review of systematic reviews. From a total of 175 hits in the search which was conducted in two parts, 16 full text articles were assessed for eligibility, from which four were selected to be included in the review. Results: Four systematic reviews of moderate quality consisting of variety of methodologies were included. The empirical evidence was limited but supportive that goal directed interventions may contribute to better engagement in rehabilitation and better outcomes of occupational performance. Limited evidence suggested that goal setting improved adherence to the treatment regimens and that patient’s active participation in goal setting had positive impact on patients and their engagement in the process. Findings suggested that goal-directed interventions, particularly in outpatient rehabilitation, may improve patients’ occupational performance. Findings related to participation outcomes were minimal. Conclusion: Goal setting is a complex and multidimensional process. Goal setting may contribute to improved engagement in rehabilitation and occupational performance outcomes for patients with ABI. / <p>Presentation was completed via Adobe Connect</p>
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Informational constraints and organisation of behaviourvan Dijk, Sander Gerrit January 2014 (has links)
Based on the view of an agent as an information processing system, and the premise that for such a system it is evolutionary advantageous to be parsimonious with respect to informational burden, an information-theoretical framework is set up to study behaviour under information minimisation pressures. This framework is based on the existing method of relevant information, which is adopted and adapted to the study of a range of cognitive aspects. Firstly, the model of a simple reactive actor is extended to include layered decision making and a minimal memory, in which it is shown that these aspects can decrease some form of bandwidth requirements in an agent, but at the cost of an increase at a different stage or moment in time, or for the system as a whole. However, when combined, they do make it possible to operate with smaller bandwidths at each part of the cognitive system, without increasing the bandwidth of the whole or lowering performance. These results motivate the development of the concept of look-ahead information, which extends the relevant information method to include time, and future informational effects of immediate actions in a more principled way. It is shown that this concept can give rise to intrinsic drives to avoid uncertainty, simplify the environment, and develop a predictive memory. Next, the framework is extended to incorporate a set of goals, rather than deal with just a single task. This introduces the task description as a new source of relevant information, and with that the concept of relevant goal information. Studying this quantity results in several observations: minimising goal information bandwidth results in ritualised behaviour; relevant goal and state information may to some point be exchanged for one another without affecting the agent’s performance; the dynamics of goal information give rise to a natural notion of sub-goals; bottlenecks on goal memory, and a measure of efficiency on the use of these bottlenecks, provide natural abstractions of the environment, and a global reference frame that supersedes local features of the environment. Finally, it is shown how an agent or species could actually arrive at having a large repertoire of goals and accompanying optimal sensors and behaviour, while under a strong information-minimisation pressure. This is done by introducing an informational model of sensory evolution, which indicates that a fundamental information-theoretical law may underpin an important evolutionary catalyst; namely, even a fully minimal sensor can carry additional information, dubbed here concomitant information, that is required to unlock the actual relevant information, which enables a minimal agent to still explore, enter and acquire different niches, accelerating a possible evolution to higher acuity and behavioural abilities.
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