Browsing by Subject "Behavior and Behavior Mechanisms"
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Item A Path Analysis of Body Mass Index, Body Image, and Unhealthy Dietary Behavior as Contributors to Suicidal Behavior in Female Adolescents(2004-05-01) Rorie, Michele Taylor; Balcazar, Hector; Lurie, Sue; ReneRorie, Michele Taylor, A Path Analysis of Body Mass Index, Body Image and Unhealthy Dietary Behavior as Contributors to Suicidal Behavior in Female Adolescents. Doctor of Public Health (Social and Behavioral Sciences), May 2004, 120 pp., 17 tables, 6 illustrations, references, 106 titles. Objectives- This study examined the pattern and magnitude of relationships between body mass index, body image, unhealthy dietary behaviors, and suicidal behavior among a sample of White, African American, and Hispanic adolescent females. Methods-This study employed secondary analysis of the 2001 Youth Risk Behavior Survey public-use dataset to provide quantitative estimates of the causal connections between body mass index, body image, dietary behaviors, and suicidal behavior. A sample (n=5,218) of White, African American, and Hispanic adolescent females aged 14-17 were selected for analysis. This cross-sectional study involved public high school students in grades 9-12. The variables/constructs BMI, Body Image, and Dietary Behavior were examined using a path analysis to determine the magnitude of effects on Suicidal Behavior in adolescent females. Results- The path coefficients were obtained for the path model using multiple regression equations, which took direct and indirect effects into account. The Female Adolescent Model (n= 5,218) yielded an R2 = .27. This meant that 27% of the variance in Suicidal Behavior was explained by BMI, Body Image, and Dietary Behavior. When race/ethnicity was analyzed separately, different values were observed. The White Adolescent Female Model (n=2,768) had an R2=.32. The Black or African American Model (n=1,206) had an R2=.23, and the Hispanic or Latino Model (n=1,224) had an R2=.27. Conclusion- The basic state of what is an actual fact about a person (i.e. weight) does not cause an increase of harmful or destructive behavior. The person’s beliefs drive intention as it was demonstrated through the immergence of significant indirect pathways from BMI through Body Image and Dietary Behavior to Suicidal Behavior. The path analyses for the three racial groups suggest that there are varying degrees of influence among BMI, Body Image, Dietary Behaviors, and Suicidal Behaviors.Item Advance Directives Planning Among Mexican-Americans in Dallas-Fort Worth(2005-05-01) Santiago, Carmen; Lurie, Sue; Gonzalez, Adela; Rene, AntonioSantiago, Carmen C., Advance Directives Planning Among Mexican-American in Dallas Fort Worth. Doctor of Public Health (Social and Behavioral Sciences), May 2005, 133 pp., bibliography, 33 titles. This qualitative study explored the knowledge base of advance directives planning among Mexican-Americans in the Dallas-Fort Worth area. In addition, the study explored areas that influenced their willingness to engage in advance directives and their preferences related to family collective decision-making. Two focus groups, representing two different populations were conducted. One focus group represented second generation Mexican-Americans, 65 years old and older, both men and women that were hospitalized or participated in home health care programs between January 2004 and January 2005. The second focus group consisted of Mexican-Americans, 18 years and older who were family members or caregivers of sick elders in the same time frame. Questions utilized to gather the knowledge and beliefs of the focus group participants, were based on a previous study by Dr. Morrison and Dr. Meir conducted in New York. Participant’s responses were analyzed using NVIVO software. Findings indicated a lack of knowledge of advance directives and confusion about state wills and living wills among Mexian-Americans in Dallas-Fort Worth. A majority of the focus group participants expressed a preference for their older children to make the decisions of their end of life care. This was due to a belief that their child is better educated and could make the right decision. Participants also revealed the importance of a family collective decision. This belief in family unity kept them from excluding members from the decision of end of life care. Another interesting finding from this study was a majority of the participants had already made funeral plans such as arranging for the lot to be buried in and funeral service pre-paid, but had not considered advance care directives. According to both groups of participants, arranging for their funeral service gave them a peace of mind and dignity since they had established where they will be interred. These findings suggested that the Mexican-American population needs to be informed about this legal process. Mexican-Americans need to be aware that the State provides ways to obtain this documentation at no cost. Health care providers should be involved in the education about advance directives and encourage their patients to learn more and consider obtaining one. Further research studying Mexican American knowledge and beliefs, at state level and a comparison among states should be explored. Keywords; advance directives, decision making, end of life, ethical issuesItem Benefits, Challenges, and Future Directions: Making the Case for eTMF in Clinical Research(2016-12-01) Beckham, Amber C.; Patricia A. Gwirtz; Stephen O. MathewIn clinical research there are many documents that must be retained in order to evaluate a trial, known as essential documents and collectively held in a trial master file. A trial master file can show if a trial was conducted according to regulatory standards. Traditionally this file has contained all paper documents, but with the advancement of technology, an electronic trial master file is now available. Although the technology of electronic trial master files exists, some organizations are still reluctant to make the switch from paper to electronic. This practicum aims to measure current opinions about the use of an electronic trial master file, as well as determine what benefits and challenges are associated with using an electronic trial master file. Finally, this project aims to show the promising future and usefulness of an electronic trial master file in order to make the case for using an electronic trial master file in clinical research. This project will use a survey of clinical research professionals working at a CRO and an illustrative comparison in order to support the hypothesis that the benefits of using an electronic trial master file compared to a paper trial master file outweigh the challenges. Participants of this project are generally in favor of using an electronic trial master file over a paper one, and they believe that using and electronic trial master file has positively impacted the role they have in clinical research. Although respondents view electronic trial master files as a good investment, they are also aware that there is room for improvement and have used their industry knowledge and experience to suggest future directions for the continued adoption and use of electronic trial master files.Item Corticotropin-Releasing Factor and Corticosterone Modulate the Anxiogenic-Like Effects of mCPP(1998-06-01) Jenkins, Jennifer A.; Michael Forster; Robert Luedtke; Patricia GwirtzJenkins, Jennifer A., Corticotropin-Releasing Factor and Corticosterone Modulate the Anxiogenic-Like Effects of mCPP. Doctor of Philosophy (Pharmacology), June 1998, 119 pp., 2 tables, 29 figures, bibliography, 100 titles. The administration of PTZ or mCPP produces anxiety-like behavior as measured by an increase in the percentage of entries into the open arms and the time spent on the open arms of the elevated plus maze (Prunell et al., 1994). Reportedly, PTZ and mCPP substitute for each other in the drug discrimination paradigm (Wallis and Laz, 1998). It is therefore suggested that commonality exists among anxiogenic drugs as perceived by trained animals. Andrews and Stephen (1990) suggested that this overall parallelism is an indication that anxiogenic agents may possess similar properties. Therefore, the question posed is as follows: Is there a common denominator anxiety? The global hypothesis is that the core component of anxiety produced by anxiogenic agents or processes involves stimulation of the HPA axis to release CRF, ACTH and/or CORT. Long Evans rats were trained to discriminate either mCPP (1.4 mg/kg) or PTZ (16mg/kg) from saline in a two-lever choice procedure (FR10) which is food reinforced. Animals were pretreated with CRF, α-helical CRF (a CRF antagonist), two steroid synthesis inhibitors (ketoconazole, KETZ and aminoglutethimide, AMG), CORT or underwent an adrenalectomy prior to behavioral testing in order to test the hypothesis that the release of CRF and/or CORT are components of the discriminate stimulus of the mCPP and/or PTZ. Pretreatment with CRF, KETZ, AMG and an adrenalectomy facilitated mCPP level selection. However in the absence of mCPP neither drug nor adrenalectomy produced drug lever selection. In addition CORT did not alter the mCPP dose response curve. However, CORT replacement therapy returned the does response curve to baseline in adrenalectomized animals. Alpha-helical CRF did not block mCPP discrimination. Unlike mCPP-trained animals, KETZ and AMG decreased PTZ-lever selection in PTZ-trained animals. In addition, CORT enhanced and partially substituted for the discriminative stimulus of PTZ. However, adrenalectomy completely abolished drug lever selection in PTZ animals. To compare the discriminative stimulus effects of mCPP and PTZ, PTZ-trained animals were injected with cumulative doses of mCPP. mCPP-trained animals were injected with cumulative doses of PTZ. mCPP and PTZ minimally substituted for each other. The results suggested that neither CRF nor CORT are components of the discriminative stimulus of mCCP and that the role of the HPA axis in mCPP discrimination maybe be a modulator of the stress response. However, CORT is a component of the discriminative stimulus of PTZ such that CORT is necessary for drug lever selection in PTZ trained animals.Item Cross-Tolerance Between the Discriminative Stimulus Properties of Ethanol, Diazepam and Pentobarbital(1995-12-01) Lytle, Douglas A.; Michael Forster; Glenn Dillon; Thomas YorioLytle, Douglas A., Cross-Tolerance Between the Discriminative Stimulus Properties of Ethanol, Diazepam and Pentobarbital. Doctor of Philosophy (Biomedical Sciences), December, 1995, 132 pp., 8 tables, 19 figures, bibliography, 176 titles. Ethanol, benzodiazepine agonists and barbiturates all facilitate GABA-mediated CT flux. The present experiments tested the hypothesis that, because these agents share this common action, tolerance to discriminative stimulus properties of one of these drugs would result in cross-tolerance to the others. Rats were trained to detect either ethanol (EtOH; 1.0 g/kg), the benzodiazepine diazepam, (DZP; 5.6 mg/kg), or the barbiturate pentobarbital (PB; 10.0 mg/kg) from vehicle using a two-lever choice procedure where food was available under a fixed-ration ten schedule of reinforcement. Subsequently, dose-effect curves for EtOH (0.1-1.78 g/kg), DZP (0.56-17.8 mg/kg), or PB (1.0-17.8 mg/kg) were tested before and after chronic administration of EtOH 96.0 g/kg/12hrs for seven days), DZP (20.0 mg/kg/8hrs for seven days), or PB (32.0 mg/kg/8hrs for seven days). The chronic administration of EtOH conferred tolerance to itself in all cases and cross-tolerance to DZP and PB in subjects trained to detect EtOH, but did not confer cross-tolerance to these agents in their respective discriminations. The chronic administration of DZP conferred tolerance to itself substituting for DZP. Although tolerance developed to DZP substituting for PB after treating animals with chronic DZP, this regimen on DZP did not confer tolerance to itself substituting for EtOH. This regimen of DZP failed to confer significant cross-tolerance to either EtOH or PB under any conditions. The chronic administration of PB conferred tolerance to itself substituting for PB. Although tolerance developed to PB substituting for DZP after treating animals with chronic PB, this regimen of PB did not confer tolerance to itself substituting for EtOH. This regimen of PB failed to confer significant cross-tolerance to either EtOH or DZP under any conditions. In summary, EtOH was found to confer cross-tolerance to DZP and PB only in animals trained to detect EtOH. The chronic administrations of DZP and PB failed to confer tolerance to themselves substituting for EtOH. These results are parsimonious with the heterogeneous nature of the GABA receptor. Finally, tolerance to either DZP or PB does not result in cross-tolerance to the discriminative stimulus properties of the other drug. These results suggest that the mechanisms mediating tolerance to BZs and barbiturates are not linked.Item Differences in Risk of Injury Between Stimulant-Treated and Untreated ADHD Patients(2006-08-01) Segars, Larry W.; Raghbir Sandhu; Krisine LykensSegars, Larry W., Differences in Risk of Injury between Stimulant-Treated and Untreated ADHD Patients. Doctor of Public Health (Epidemiology), August 2006, 63 pp, 7 tables, 0 illustrations, references, 78 titles. ADHD is a common psychiatric disorder of childhood and adolescence that also occurs in adults and spans the life of the patient. ADHD is characterized by lack of focus, distractibility, and poor concentration. Limited data have been generated focusing on ADHD patients and the association with an increased risk of injury. Unfortunately, no study has been published evaluating the effect of stimulant treatment for ADHD on the risk of injury requiring ambulatory medical care. This research utilized four concatenated years, specifically 1998-2001, of the National Ambulatory Medical Care Survey (NAMCS). This dissertation is comprised of five chapters beginning with a description of ADHD, its characteristics, diagnosis, and treatment. This overview chapter is followed by a complete review of the literature describing the publication’s which assessed the association between ADHD and the risk of injury. The next chapter is a thorough review of the NAMCS and its methodology. The concatenated dataset captured 889 office visits associated with a diagnosis of ADHD, 666 of which were also related to the prescription of a stimulant for the management of ADHD. Using NAMCS’s weight variable these values produced a national estimate of 21,223,391 office visits associated with the ADHD diagnosis and 15,604,329 office visits associated with the prescription of a stimulant for ADHD. This research determined that there was a borderline statistically significant increased association with the prescription of a stimulant for the treatment of ADHD and the risk of injury requiring treatment in an ambulatory medical care setting. Interestingly, compared to patient’s who recorded their race as Caucasian, patients who recorded their race as “Other”; representing the races of Asian, Native Hawaiian/Other Pacific Islander, or American Indian/Alaska Native, and individuals indicating more than one race, had a statistically significant increased risk of injury necessitating treatment in an ambulatory medical care setting. Potential theories for this unique finding, along with the limitations of this research, are provided in the final discussion chapter.Item Discriminative and Negative Reinforcing Properties of the Periaqueductal Gray and the Medial Hypothalamus(1994-12-01) Jung, Marianna E.; Emmett-Oglesby, Michael W.; Yorio, ThomasMarianna Eunsun, Jung, Discriminative and Negative Reinforcing Properties of Electrical brain stimulation of the Periaqueductal Gray and the Medial Hypothalamus. Master of Science [Biomedical Sciences, (Pharmacology)], December, 1994, 123 pp., 24 figures, references, 137 titles. Electrical brain stimulation (EBS) of the periaqueductal gray (PAG) and the medial hypothalamus (MH) is known to serve as a discriminative and a negative reinforcing stimulus (NRS). Using a two-lever food reinforced discrimination paradigm and a switch-off paradigm, the present study investigated the effects of anxiolytic drugs and an anxiogenic drug on these stimulus effects. A prototypic anxiogenic, pentylenetetrazole (PTZ) potentiated both discriminative stimulus and NRS effects, whereas the full benzodiazepine (BZD) agonist diazepam (DZP), the partial BZD agonist abecarnil (ABC) and 5-HT1A agonist buspirone (BUS, chronic regimen) attenuated a NRS effect. A BZD antagonist, flumazenil (FLU) blocked the effects of DZP and ABC on the NRS effects. DZP failed to attenuate the discriminative stimulus effect. Thus, present study extended the use of a switch-off paradigm to detect novel anxiolytic ABC (putative) and BUX as well as an anxiogenic PTZ. In addition, under the condition used in this study, the use of NRS in a switch-off paradigm more reliably detected both anxiolytic drugs and an anxiogenic drug than the use of discriminative stimulus in a two-lever food reinforced paradigm.Item Divergent Behavioral Phenotypes in Conditioned Place Preference(2017-12-01) Wagner, Alison N.; Forster, Michael J.; Gatch, Michael B.; Shetty, RituThe addictive properties of psychostimulants have been studied using a variety of animal models and behavioral paradigms. These studies consistently report individual variation in drug response that could reflect subgroups with different susceptibility to addiction. A place conditioning assay was used to assess the possibility that such divergent behavioral phenotypes explain variable outcomes in mice after conditioning with psychostimulants (cocaine, 3,4-methylenedioxypyrovalerone (MDPV), methamphetamine, and d-amphetamine). K-means clustering analysis partitioned individuals into groups (i.e. clusters) for analysis. The reliability of these phenotypes was supported with Pearson correlation analysis comparing adjacent time points, as well as Cronbach’s alpha and intraclass correlation coefficients for overall within-group relatedness at each time point. Furthermore, initial preference developing in a drug-naïve condition was reversed with drug conditioning, demonstrating that changes in salience were sufficient to reverse initial preference in some mice. By purposefully examining these behavioral phenotypes in place conditioning, we advance toward the development of pharmacological strategies for addiction and robust epigenetic outcomes.Item Examining Coronary Heart Disease Risk Factors and Its Relationship with Physical Activity in a Self-Reported Survey(2004-05-01) Fernandes, Alroy H.; Frederick Fridinger; Daisha Cipher; Claudia CogginFernandes, Alroy H., Examining Coronary Heart Disease Risk Factors and its Relationship with Physical Activity in a Self-Reported Survey. Masters of Public Health (Community Health), May 2004, 49pp., 3 illustrations, references, 38 titles. This study uses ‘Healthstyles,’ a self reported survey of 3,719 respondents above the age of 18, to look at exercise behavior in people at risk for CHD. Married or higher earning individuals were more likely to show sufficient exercise levels. Individuals with high blood pressure, high blood cholesterol, diabetes, obesity or family history of heart disease reported lesser levels of sufficient exercise than those without these conditions. People with CHD risk factor reported lower scores on questions that dealt with attitude and opinions about exercise behavior, and this was significantly correlated with lower levels of sufficient exercise. This supports the ‘positive attributes of the behavior’ aspect of the social cognitive theory of exercise. The attitude questions used, although not specific, could be included in a self-reported survey for the purpose of qualitatively and quantitatively assessing exercise intervention; albeit more studies are required to validate this claim.Item Gender Differences: Making the Decision to Seek Treatment for Symptoms of Acute Myocardial Infarction(2000-05-01) Borski, Catherine A.; Shelia Reed; Joseph Doster; Claudia CogginBorski, Catherine A., Gender Differences: Making the decision to seek treatment for symptoms of acute myocardial infarction. Masters of Public Health (Health Behavior), May, 2000, 57 pp., reference list, 37 titles. The purpose of this study was to investigate the problem: Do differences in interpretation and response to symptoms of AMI account for additional delay in seeking treatment in women compared with men? The sample consisted of 50 (21 women, 29 men) post-myocardial infarction patients in a large, non-profit, teaching hospital in central Texas. Participants were interviewed within 72 hours of admission using the Revised Response to Symptoms questionnaire. In this study, it was found that there was a statistically significant difference between the cognitive and emotional processes that men and women use when making the decision to seek treatment for symptoms of AMI.Item HIV Related Risk Behaviors: A Comparitive Study of Urban, Suburban, and Rural U.S. Adolescents(2006-08-01) Patil, Godavari D.; Karan Singh; Sejong Bae; Francise Soto MasGodavari D. Patil, HIV Related Risk Behaviors: A Comparative Study of Urban, Suburban, and Rural U.S. Adolescents. Masters of Public Health (Biostatistics), August 2006, 120 pp., 29 tables, References, 209 titles. This explorative study YRBS 2003 data provides the prevalence of HIV-related risky sexual behaviors and predictors of such behaviors across gender, race/ethnicity, and metro status (N=15, 214) during 2003. Overall, more urban male adolescents engaged in health-compromising behaviors. A significant association was found between gender, race/ethnicity, and metro status and sexual behaviors and associated risk behaviors such as alcohol, drug use, and mental health indicators. These associated risk behaviors were not only associated among themselves and with sexual behaviors variables but also turned out to be responsible predictor variables for HIV related sexual risk behaviors. Minority groups especially black adolescents were at higher risk of contracting HIV infection as having multiple sexual partners was highest (8 fold) among black adolescents compared to mixed & other race, and Hispanic adolescents. Suburban adolescents were nearly two times more likely that rural and urban adolescents to having multiple partners. Results indicated that younger the age more the involvement in sexual and other risky behaviors.Item Hooper Visual Organization Test (VOT) as a Predictor of Driving Status of Individuals with Dementia(2004-04-01) Budd, Margaret Anne; Doug A. Main; Susan FranksHooper Visual Organization Test (VOT) (Hooper, 1983) items were correlated with driving status of geriatric individuals with dementia to help screen for high-risk drivers. A retrospective review of 87 medical chart on patients, 60-91 years, who underwent a neurocognitive evaluation at the University of North Texas Health Science Center in Fort Worth, Texas, with a complete VOT, driving status, dementia diagnosis, and demographic descriptors (age, gender, marital status) were selected for analysis. Of the 55.2% participants who reported a current driving status, VOT scores ranged: 20.8% normal, 43.8% mildly impaired, 31.3% moderately impaired, and 4.2% severely impaired. An item analysis was followed by direct logistic regression analysis which correctly predicted 85% of the drivers and 74% of the nondrivers with an overall success rate of 80.5% (p=.001). The Wald criterion selected 4 VOT items as reliably predicting driving status: items 6 (hammer), 19 (teapot/pitcher), 22 (mouse), and 25 (block). Models run with gender and/or marital status was not reliably different. These 4 items may add to a brief screening test to identify drivers with dementia potentially at risk. In addition, the large number of current drivers scoring in the impaired range suggests that individuals, their families and others are not intervening with driving behavior, possibly placing the individuals and public at risk.Item Interactive Effects of Mental and Physical Stress on Cardiovascular Control(1998-08-01) Westerholm, Erin Carpenter; Smith, Michael; Raven, Peter B.; Shi, XiangrongWesterholm, Erin C., Interactive Effects of Mental and Physical Stress on Cardiovascular Control. Master of Science (Biomedical Sciences, Integrative Physiology), August, 1998, 42 pp., 1 table, 13 figures, 35 references. Mental task and exercise often occur together. Physiological responses to each of these stressors have been studied independently, yet the interactive effects of these stressors are unknown. Hypothesis: Combined mental and physical stress will produce a synergistic interaction. Methods: Twelve healthy subjects were studied by measuring cardiovascular responses to five minutes of static left handgrip alone (25-35% of maximal handgrip strength), mental arithmetic alone, and combined stimuli in random order. Sympathetic nerve activity (SNA, microneurography), mean arterial blood pressure (MAP, Finapres), heart rate (HR, ECG), and vascular resistance (Doppler) were measured. Results: Physical and combined stressors significantly changed SNA, MAP, HR, and FVR. SNA responses to handgrip and the combined stimuli exceeded responses to mental arithmetic alone (p [less than] 0.05), yet no significant difference existed between responses to handgrip alone and the combined stimuli (p=0.33). The three stimuli increased heart rate similarity (p [less than] 0.0006). Conclusion: The data refuted the hypothesis: mental task did not synergistically interact or even add to the stress response elicited by handgrip exercise. Thus these data suggest that mental task and static exercise interact in a redundant manner.Item Investigating the Role of Stress in a Murine Model of Asthma(2008-07-01) Deshmukh, Aniket; Harlan Jones; P. Mathew; Jerry SimeckaThe mechanisms by which stress can exacerbate asthma are still unknown. The purpose of this study was to examine the immunological links between stress controllability and asthma pathogenesis. Our studies reveal specificity of stress control and immune activation resulting in hyper-inflammatory reactions in response to allergic airway challenge. We anticipate that these studies can serve as a translational piece to facilitate clinical studies of stress and asthma prevalence. The purpose of this project was to establish a murine model of stress controllability and demonstrate the impact of stress on the development of immune allergic airway hypersensitivity as a major feature of asthma. I hypothesized that given the ability to control the degree of stress would translate into less severe allergic airway hypersensitivity. We also hypothesized that distinct changes in immune responses generated in response to uncontrolled stress would reflect the extent of airway hypersensitivity. Mice were exposed to daily regimen of uncontrollable stress, controllable stress or no stress concurrently with allergen exposure. Behavioral disposition to stress was monitored in conjunction with evaluation of severity of asthma and immune status. Our results demonstrate that exerting control over stress conditions leads to distinct changes in immunological status corresponding with positive behavioral responses and less disease severity. We anticipate that our studies will facilitate application of stress management in control of immune status as a biomarker for asthma progression.Item Lectures on Conditioned Reflexes Twenty-five Years of Objective Study of the Higher Nervous Activity (Behaviour) of Animals(International Publishers, 1928-01-01) Gantt, W.; Volborth, G.; Cannon, Walter; Pavlov, IvanTranslator's Preface 9 I. P. Pavlov: A Biographical Sketch, By Dr. W. Horsley Gantt . 11 Introduction To The English Translation, By Prof. Walter B. Cannon 33 Author's Preface To The English Translation 35 Preface To The First Russian Edition • 37 Chapter. I. Experimental Psychology And Psycho-Pathology In Animals – 47 II. . The Psychical Secretion Of The Salivary Glands (Complex Nervous Phenomena In The Work Of The Salivary Glands) 61 III. The First Sure Steps Along The Path Of A New Investigation 76 IV. Scientific Study Of The So-Called Psychical Processes In The Higher Animals 81 V. Conditioned Reflexes In Dogs After Destruction Of Different Parts Of The Cerebral Hemispheres 97 VI. The Cortical Taste Centre Of Dr. Gorshkov 99 VII. Mechanism Of The Highest Parts Of The Central Nervous System As Shown From The Study Of The Conditioned Reflexes 100 VIII. Further Advances Of The Objective Analysis Of Complex Nervous Phenomena, And Its Comparison With The IX. Subjective Conception Of These Phenomena • 103 X. Some General Facts About The Cerebral Centres , 115 XI. Natural Science And The Brain 120 XII. The Task And The Arrangement Of A Laboratory For The Study Of The Normal Activity Of The Highest Parts Of The Central Nervous System In The Higher Animals • 131 XIII. A Laboratory For The Study Of The Activity Of The Central Nervous System In The Higher Animals 144 XIV. The Food Centre • 147 XV. Some Fundamental Laws Of The Work Of The Cerebral Hemispheres 156 XVI. Destruction Of The Skin Analyser 165 XVII. The Process Of Differentiation Of Stimulations In The Hemispheres Of The Brain 170 XVIII. Some Principles Of The Activity Of The Central Nervous System As Shown From The Study Of Conditioned Reflexes ; Interaction Of Centres 182 XIX. Summary Of Results Of Removal Of Different Parts Of The Cerebral Hemispheres 193 XX. Internal Inhibition As A Function Of The Cerebral Hemispheres 205 XXI. The Objective Study Of The Highest Nervous Activity Of Animals . 213 XXII. The Study Of The Highest Nervous Activity • 223 XXIII. The Instability (Lability) Of Internal Inhibition In Conditioned Reflexes . 238 XXIV. The Pure Physiology Of The Brain 241 XXV. Some Facts About The Physiology Of Sleep 250 XXVI. An Analysis Of Some Complex Reflexes In The Dog; And The Relative Strength And Tension Of Several Centres 255 XXVII. Physiology And Psychology In The Study Of The Higher Nervous Activity Of Animals 261 XXVIII. The Reflex Of Purpose 275 XXIX. The Reflex Of Freedom 282 XXX. How Psychiatry May Help Us To Understand The Physiology Of The Cerebral Hemispheres 287 XXXI. Hypnotism In Animals 294 XXXII. The Normal Activity And General Constitution Of The Cerebral Hemispheres . 296 XXXIII. Internal Inhibition And Sleep-One And The Same Process 305 XXXIV. Changes In The Excitability Of Various Points Of The Cerebral Cortex As One Of Its Functional Characteristics 319 XXXV. Another Problem In Cerebral Physiology 326 XXXVI. The Latest Successes Of The Objective Study Of The Highest Nervous Activity 329 XXXVII. Relation Between Excitation And Inhibition And Their Delimitations; Experimental Neuroses In Dogs 339 XXXVIII. Effect Of Interrupting The Experimentation In Dogs With Conditioned Reflexes 350 XXXIX. Normal And Pathological States Of The Hemispheres 353 XL. The Inhibitory Type Of Nervous Systems In The Dog 363 XLI. A Physiological Study Of The Types Of Nervous Systems, I.E., Of Temperaments • 370 XLII. Certain Problems In The Physiology Of The Cerebral Hemispheres 379 Bibliography • 395 Index To Names 409 Index To .Subjects 410Item Local Enkephalins Modulate Vagal Control of Heart Rate(2001-05-01) Jackson, Keith E.; James L. Caffrey; H. Fred Downey; Michael W. MartinJackson, Keith E., Local Enkephalins Modulate Vagal Control of Heart Rate. Doctor of Philosophy (Biomedical Sciences), May 2001; 112pp; 7 tables; 22 figures; bibliography, 99 titles. Endogenous opioids, such as enkephalins, were first investigated for their ability to modulate pain. A body of evidence now supports opioid actions in many facets of regulation, including the cardiovascular system. Our laboratory is particularly interested in the ability of opioids to modulate autonomic function. Specifically, the role of the endogenous encephalin, methionine-enkephalin-arginine-phenylalanine (MEAP) was investigated to determine its ability to modulate parasympathetic function in the canine. To investigate MEAP’s response in the sinoatrial (SA) node a novel application of microdialysis was employed, whereby microdialysis was employed, whereby microdialysis probes were fabricated as described by Dr. David Van Wylen (38), and implanted in the SA node. After implantation of the probe, there was a significant attenuation of vagal function during the nodal application of MEAP. Specifically, vagally mediated bradcardia was reduced as compared to control, during the nodal application of MEAP. This inhibition of the vagus by MEAP was blocked by naltrindole, a selective delta antagonist. These data suggested that the vagolytic effects of MEAP were elicited via a delta opioid receptor. To test the hypothesis that MEAP’s effects were elicited through a delta opioid receptor mechanism, selective agonists and antagonists for the opioid receptors were utilized. An attenuation of vagal bradycardia was only observed during the infusion of a very selective delta opioid receptor agonist, deltorphin. A mu and kappa agonist showed no significant differences from control. Deltorphin was observed to elicit vagolytic effects in a similar concentration range as MEAP. However, deltorphin was more efficacious that MEAP. There was a significant attenuation of the deltorphin and MEAP’s vagolytic effects, during the co-infusion of the selective delta antagonist, naltrindole. The mu and kappa antagonists were both ineffective. These data further demonstrate that the observed vagolytic effect is linked to a delta opioid receptor. Endogenous MEAP. A series of experiments were undertaken to determine if endogenous MEAP could be demonstrated in the SA node and is so, was it similarly vagolytic. A preconditioning-like protocol was performed to produce intermittent local nodal ischemia to increase the local concentration of endogenous MEAP. The resulting MEAP was measured and was observed to be elevated during the periods of local nodal ischemia and return to control during reperfusion. Contrary to expectations an augmentation of vagal function was observed, during vagal stimulation. The augmented vagal bradycardia was only observed during ischemia, when MEAP was elevated and returned to control during each subsequent reperfusion. Therefore, there was a correlation between elevated MEAP concentrations and augmented vagal bradycardia. The delta antagonist, naltrindole, prevented the augmented vagal response, during nodal ischemia Glibenclamide, a selective KATP channel blocker, partially reversed the augmented vagal response. These data confirm that delta opiate receptors are involved in the augmented vagal bradycardia and that the mechanism may involve the activation of a KATP channel.Item Mechanisms of Chemoreflex Control of Muscle Sympathetic Nerve Activity and Blood Pressure in Humans(2004-05-01) Hardisty, Janelle M.; Smith, Michael; Shi, Xiangrong; Clark, MichaelHardisty, Janelle M., Mechanisms of Chemoreflex Control of Muscle Sympathetic Nerve Activity and Blood Pressure in Humans. Doctor of Philosophy (Integrative Physiology), May 2004. The mechanisms linking obstructive sleep apnea (OSA) and cardiovascular disease are not fully understood; however, studies report patients with OSA exhibit chronic elevations in muscle sympathetic nerve activity (MSNA). This appears to be due to altered chemoreflex control of MSNA, mediated primarily by hypoxia. Yet, a correlation between degree of hypoxia and chemoreflex control of MSNA is unknown. Therefore, it was evaluated whether degree of hypoxia occurring during apnea determines the sympathoexcitatory and blood pressure responses, and whether these responses are augmented in OSA patients. Additionally, it was studied whether altered chemoreflex function in OSA patients is predictive of blood pressure response to apnea. In a clinical setting, the blood pressure response to voluntary apnea was determined to evaluate whether this could be used as a non-invasive measure of chemoreflex gain in OSA. Finally, the effect of hyperoxia on MSNA was studied to determine whether 15 min of hyperoxia, following intermittent hypoxic apnea, reverses the elevation of MSNA and altered chemoreflex control of MSNA. Consistent with the hypotheses, a relationship between MSNA responses, blood pressure response and level of hypoxia were determined. MSNA and peak systolic pressure responses were augmented in OSA subjects (p≤0.05 and p≤0.05, respectively), as well as, chemoreflex gain (p≤0.05). Clinically, peak systolic pressure responses to apnea were augmented in OSA patients (p˂0.001). Finally, basal MSNA and chemoreflex control of MSNA, following hyperoxia, was not different from baseline through 180 min of recovery (p=0.940 and p=0.278, respectively). These data support the hypotheses that chemoreflex gain is predicative of the blood pressure response; and furthermore, the MSNA and blood pressure responses to hypoxic apnea are augmented in OSA. Additionally, peak systolic pressure responses to voluntary apnea are augmented in OSA. Additionally, peak systolic pressure responses to voluntary apnea are augmented in OSA patients and could possibly be used as a marker of chemoreflex gain. Moreover, these data support the hypothesis that hyperoxia can reverse basal sympathoexcitation and augmented chemoreflex control of MSNA, associated with hypoxic apnea, supporting that elevations in MSNA are hypoxia mediated.Item Mechanisms of Post-Apneic Symathoinhibition in Humans(2002-08-01) Swift, Nicolette Muenter; Michael Smith; David Barker; John R BurkMuenter Swift, Nicolette, Mechanisms of Post-Apneic Sympathoinhibition in Humans. Doctor of Philosophy (Biomedical Sciences), August, 2002, 110 pp., 14 figures, references. Apnea is accompanied by a concomitant rise in arterial pressure and muscle sympathetic nerve activity (MSNA), the latter primarily due to chemoreflex stimulation and possibly the lack of sympathoinhibitory input from pulmonary stretch receptors. The progressive sympathoexcitation during apnea suggests a possible overriding of arterial baroreflex sympathoinhibitory input to sympathoregulatory centers by apnea-induced sympathoexcitatory mechanisms. Nevertheless, it is unknown whether apnea attenuates baroreflex control of MSNA. Apnea termination is accompanied by a profound and immediate sympathoinhibition, the mechanisms of which are unclear; however, potential mediators include normalization of blood gases (i.e. chemoreflex unloading), the lung inflation reflex, and arterial baroreflex stimulation. Therefore, the purpose of the current studies was to: i) determine the contribution of chemoreflex unloading to post-apneic sympathoinhibition, ii) determine the contribution of the lung inflation reflex to post-apneic sympathoinhibition, and iii) determine whether carotid baroreflex control of MSNA is altered by apnea and its termination. The first study compared MSNA during post-apneic administration of room air versus a gas mixture designed to maintain the subjects’ end-apneic alveolar gas levels. Regardless of post-apneic gas administration, post-apneic MSNA was at or below baseline pre-apneic levels; thus; chemoreflex unloading does not contribute to post-apneic sympathoinhibition. Furthermore, quantification of post-apneic MSNA associated only with the low lung volume phase of respiration, when sympathoinhibitory input from the lung inflation reflex is minimal, demonstrated that post-apneic sympathoinhibition persists even during the low lung volume phase of respiration, when sympathoinhibitory input from the lung inflation reflex is minimal, demonstrated that post-apneic sympathoinhibition persists even during the low lung volume phase of respiration. Therefore, the lung inflation reflex does not appear to be the primary mediator of post-apneic sympathoinhibition. The second study utilized neck suction (NS) and neck pressure (NP) to assess carotid baroreflex function during and following sleep apnea. The sympathoinhibitory response to -60 Torr NS was maintained throughout apnea; conversely, the sympathoexcitatory response to +30 Torr NP was attenuated for nearly one minute post-apnea. Thus, carotid baroreflex control of MSNA is not altered by apnea but is transiently attenuated by apnea termination. We propose that the carotid baroreflex-MSNA function curve resets rightward and upward during apnea. Return of the function curve to baseline upon apnea termination may partly explain the reduced MSNA response to NP post-apnea.Item Nutrition, Dementia and Depression in an Ambulatory Geriatric Care Center(2005-05-01) Birmingham, John F.; Daisha Cipher; Douglas A. Mains; Thomas J. FairchildBirmingham, John F., Nutritional Risk, Dementia Factors and Depression in an Ambulatory Geriatric Care Center. Master’s of Public Health (Clinical Research), May 2005, 60pp., 7 tables, 2 figures, reference list, 56 titles. Dementia is a major public health problem in the aging population. Depression, nutritional risk and declining self-efficacy are broadly listed risk factors for dementia. Cross-sectional patient data was obtained by chart review of ambulatory community-dwelling elderly patients screened for depression, dementia factors, levels of independence in activities associated with daily living and nutritional risk. The statistical coefficients of the correlational relationships between nutritional risks, dementia factors, depression levels and levels of functional capacity were examined using path analysis. Two models depicted the composite of instrumental activities of daily living items (IADLs), as they related to the dependent variables models, nutritional risk, dementia factors, and depression levels. The model which regressed the IADLs composite variable against depression and dementia factors indicated a good fit (X2=0.00, p=0.01). Attempts to match screening data with diagnostic follow-up data were unsuccessful. Only 12 matches occurred between the GAP and CARE databases (N=256, N=1470).Item Obstacles Associated with Physician Referral of Patients into Clinical Trials(2017-05-01) Torrez, Nick; Hodge, Lisa M.; Mathew, Stephen O.; Jung, Marianna E.Understanding the safety and efficacy of potential new medications relies on evidence gained through the participation of subjects in clinical drug trials. Many clinical trial sites struggle with recruitment of suitable participants which can delay the progress of drug development. Physicians can play a significant role in influencing patients to enter into a clinical trial, however many physicians due not utilize their unique position to facilitate the recruitment of patients into clinical trials, which may help to advance medical science and improve future treatment options. The lack of participation by physicians in the referral of patients into clinical trials (Crosson et al. 2001; Daugherty C, 1995; Jenkins and Fallowfield, 2000; Lara et al., 2001) can potentially be explained by various obstacles. We propose that these obstacles may be issues such as time, lack of knowledge about clinical trials, lack of clinical trials suitable for patients, language barriers, conflict of interest, communication with local investigators, and trust in medical researchers.