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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Seeing and Knowing Ability of Rhesus Macaques (Macaca mulatta)

Major, Christine A. 01 January 2007 (has links) (PDF)
Attribution of knowledge refers to equating a shared visual perspective with shared information, a characteristic of human behavior. However, there is considerable debate as to whether nonhuman primates understand the significance of gaze and will select a treat from an experimenter that looks at them as opposed to one that does not. In previous studies, chimpanzees could not differentiate between looking and nonlooking experimenters. However, treats were held in the hands, a considerable distance from the face. We asked whether a group of five rhesus monkeys (Macaca mulatta) could discriminate lookers from nonlookers. We eliminated the problem of focusing on the hands by holding treats in close proximity to the experimenters’ eyes. Monkeys were trained to use an apparatus to select an experimenter. All five subjects were subsequently able to discriminate between experimenters holding different food rewards, even when these rewards were placed out of the monkey’s view. Two of the monkeys could also select the experimenter who initially held a desirable treat after the treat was hidden and that experimenter changed location. On the seeing and knowing task, two probe types of visual occlusion were used: Probe 1- one experimenter turned his head away from the monkey, Probe 2- one experimenter covered his eyes with a blindfold. Position, experimenter, probe trial, and reward type (on standard trials) were block randomized. Data were analyzed using binomial probabilities with &#;=0.05. At the group level, all five monkeys requested food from the experimenter looking at them significantly more than would be expected by chance, but individual subject performance differed depending on probe condition. These data suggest that some rhesus macaques have the ability to understand the connection between seeing and knowing.
2

An Ecological Counseling Exploration of Common Marital Issues Faced by African Immigrants in the United States

GORIS, ACHA GEORGE 27 August 2008 (has links)
No description available.
3

The role of serotonin in brain development and 3,4-methylenedioxymethamphetamine-induced cognitive deficits

Schaefer, Tori L. 11 August 2009 (has links)
No description available.
4

Eye movement desensitization and reprocessing in the treatment of test anxiety: A study of the effects of eye movement and expectancy on the procedure's results

Gosselin, Philip Wenneis 01 January 1994 (has links)
Eye Movement Desensitization and Reprocessing, abbreviated EMDR, is a recently discovered technique acclaimed as a major breakthrough for the reduction of anxiety. Numerous anecdotal studies have been presented showing the efficacy of EMDR. There are currently no published studies investigating use of EMDR specifically for test anxiety. The purpose of this study was to use the EMDR technique to study its efficacy for test anxiety. This study also examined whether or not high and low expectancy conditions significantly affected scores on post-session anxiety ratings. In addition, the procedure was used with and without eye movement to see whether or not eye movement was a critical factor in eliciting positive change in anxiety ratings. A single session of approximately one hour was conducted individually with 41 subjects, college students reporting test anxiety. The subjects were randomly assigned to one of four conditions reflecting varying combinations of eye movement and expectancy conditions. A 2 x 2 analysis of variance was conducted for expectancy and eye movement factors on two dependent measures. These measures were Subjective Units of Disturbance Scale (SUDs) and the Test Anxiety Inventory (TAI). Results of the study show a significantly greater amount of reduction in the SUDs using the eye movement supporting the hypothesis that eye movement is critical to the efficacy of EMDR. No other statistically significant main effects or interactions were found with measuring the SUDs or TAI. However, it should be noted that all groups showed substantial reductions in post-treatment TAI scores. The expectancy conditions presented to subjects also had no measureably significant effects. There was anecdotal support of the power of the eye movement but no significant behavioral changes other than the reduction in SUDs. It was concluded that EMDR is worthy of further study with larger samples of the test anxious population. Further study may want to use EMDR in conjunction with other techniques and for more than one session.
5

Differentially reared juvenile rhesus (Macaca mulatta) macaques' response to novel stimuli in their home environments: A measure of behavioral flexibility

Watson, Lyna M 01 January 1995 (has links)
Thirteen differentially-reared juvenile rhesus macaques (Macaca mulatta) were subjects in a twenty-one week long study investigating macaques' behavioral responses to novel stimuli. Both animate (an unfamiliar conspecific) and inanimate objects (ball, board and hanging acrylic cylinder) were presented to the monkeys while in their home cages. All subjects were female; seven were nursery-raised/peer-reared and six family-grouped (unimale/multifemale) raised. Scan and focal-sampling techniques were used to collect data on forty-two behaviors. The fifteen most frequently occurring behaviors (each accounting for one percent of total behavioral frequencies) were statistically tested. The focal sample data was analyzed on both an overall and across treatment level using a Student's t test and Chi square analysis. The intergroup differences occurred both during baseline and manipulation periods. The family-grouped subjects approached novel stimuli earlier and interacted with the objects more often than did the peer-grouped monkeys. The intergroup differences were statistically significant (p $<$.05), both on an individual and group level. Among the similarities observed between the differentially-reared juveniles were an increase in behavioral frequencies over time, a preference for the edges rather than central portions of the cage, and comparable frequencies of aggression when the animate stimulus (unfamiliar monkey) was present. Scan samples were made on the focal juvenile-aged subjects, as well as all other members of the seven groups (two peer groups and five family groups). The animals' utilization of space and behavioral frequencies were recorded pre- and post-focal sampling observations. The peer-reared monkeys lagged behind the family-reared individuals in their occupation of cage areas near the novel stimuli by eighteen weeks. Also, the family-reared juveniles tended to approach novel stimuli in manners comparable to the adults in their groups. The peer-reared juveniles' approaches were similar in frequency and nature to the family-grouped yearling and infants' displays. A preliminary follow-up study of the animals' reproductive activity indicates intergroup differences. During their first two years of parenthood the peer-reared females became pregnant earlier and more often than family-reared females. Over the two year period the peer-reared females had fourteen pregnancies versus the family-reared females' nine. But, the peer-reared had two stillbirths, three neonatal deaths and one infant rejection. One out of nine pregnancies resulted in a stillbirth among the family-reared females. The intergroup differences and similarities, both as juveniles and as adults, are discussed as possible measures of behavioral flexibility in this species. The theoretical and practical implications of restricting macaques' social rearing conditions are presented.
6

Latently inhibited stimuli are weakened in their ability to serve as blockers and second-order reinforcers in Pavlovian fear conditioning

McPhee, Janice Elizabeth 01 January 1998 (has links)
The ability of a preexposed (latently inhibited) conditioned stimulus (CS) to serve as (a) a blocker or (b) a second-order reinforcer in Pavlovian fear conditioning was tested in albino rats. Experiment 1 found that a preexposed CS was weakened in its ability to serve as a blocker. Experiment 2 found that a preexposed CS was weakened in its ability to serve as a reinforcer for second-order conditioning (SOC). Experiment 3 found that a 28-day retention interval between the last trial of element conditioning and the first trial of the SOC test did not enhance the ability of the preexposed CS to serve as a reinforcer for SOC, even though it did enhance the ability of that preexposed CS to evoke a first-order conditioned response. Experiment 4 was undertaken in an effort to show a contextually dependent attenuation of LI by employing a context shift between preexposure and element training. However, no attenuation of LI was found. Experiment 5 successfully demonstrated an attenuation of LI by reducing familiarity with the preexposure context prior to CS preexposure, reducing the amount of CS preexposure, and by using 100% reinforcement of the target CS during the first two days of the element training phase. Experiment 6 found that conducting stimulus preexposure and the test for blocking in different contexts did not enhance the ability of a preexposed CS to block conditioning to a neutral CS. Results are interpreted as supporting a learning-deficit view of latent inhibition.
7

Neurochemical control of social behavior in male and female prairie voles (Microtus ochrogaster)

Villalba, Constanza A 01 January 2000 (has links)
Unlike most rodent models, prairie voles, show very few sex differences in social behavior. Despite the similarities in their behavior male and female voles, appear to use different physiological machinery to achieve the same behavioral goals. Therefore, male and female voles are likely to respond differently to pharmacological behavioral modifiers. To test whether the behavioral effects of serotonin potentiation vary by gender and/or reproductive context, I compared the effects of the selective serotonin reuptake inhibitor fluoxetine on parental and aggressive behavior in pairbonded, parentally-experienced male and female voles, and in pairbonded, parentally-inexperienced male and female voles. Because sociosexual experience influences the function of the serotonin system, the target of fluoxetine, I also compared serotonergic function in male and female voles that had mated, remained with a same-sex sibling, or been paired with a novel conspecific of the same sex. Fluoxetine increased the latency to parental behavior in parentally-experienced male and female voles and pairbonded, parentally-inexperienced male voles. Fluoxetine also decreased aggressive behavior in parentally-experienced male voles, but had no effect on the aggressive behavior of parentally-experienced female voles, or pairbonded, parentally-inexperienced voles of either sex. In addition, fluoxetine reduced serotonin turnover in the frontal cortex and hypothalamus/preoptic area of male and female voles. Serotonin turnover was also affected by sociosexual experience. Mating and cohabitation with a mate increased serotonin turnover in the hypothalamus of male and female voles. Furthermore, the levels of serotonin and 5-hydroxy-indoleacetic acid in the frontal cortex and amygdala were sexually dimorphic. Although this thesis focused primarily on the influence of gender and reproductive context on the behavioral effects of fluoxetine, it also revealed important aspects of parental and aggressive behavior that were independent of the effects of fluoxetine. Parentally-inexperienced female voles were infanticidal one week into pregnancy whereas their mates were parental. Furthermore, the aggressive behavior of parentally-inexperienced, pairbonded voles but not parentally-experienced voles was affected by the gender composition of the resident-intruder pair. Parentally-inexperienced, pairbonded voles were more aggressive with opponents of the same sex than opponents of the opposite-sex. The findings described in this thesis suggest that fluoxetine has sexually dimorphic effects on behavior and that sociosexual factors influence the effects of fluoxetine on behavior as well as the function of the serotonin innervation of the brain.
8

Integrating functional assessment and ecobehavioral assessment: Interventions for young children with at -risk behavior

Phaneuf, Robin Lee 01 January 2002 (has links)
This study examined the utility of an integrative assessment process in developing interventions for young children with at-risk behavior. Additionally, the study examined the effectiveness of interventions focused primarily on manipulating antecedents of the target behavior and environmental variables potentially contributing to the target behavior. Tools and procedures from functional and ecobehavioral assessment were used in a consultative process to guide the behavioral assessment and to inform the development of interventions implemented in the classroom. Specifically, interviews and observations were supplemented by an evaluation of the classroom environment, and information from these tools was used to develop interventions. Three applications of the assessment and intervention process are provided. In Case Study I, the process was used to develop interventions to increase the social play of a socially withdrawn preschool male. In Case Study II, the process was used to design interventions to increase compliance in a preschool female. Case Study III provided a small group application of the process as it was used with a classroom of six preschool age children. In all cases, antecedent-based or environmentally-based interventions derived from the integrative process were demonstrated to be effective in addressing the target behaviors. Through case study replications, this study provides support for an assessment process that integrates functional and ecobehavioral assessment as well as support for interventions focused on manipulating antecedents or environmental variables.
9

Object-oriented behavior grasping from a perception/action perspective

Loukopoulos, Loukia D 01 January 1997 (has links)
Object-oriented behavior requires the fine interplay between perception and action. Two visuomotor cortical channels are typically implicated in grasping. One is described as specifically sensitive to extrinsic object parameters (e.g., location). The other is described as specifically sensitive to intrinsic object parameters (e.g., shape). According to Jeannerod (1981), the first, dorsal, channel directs the arm transport component of a grasp, while the second, ventral, channel directs the object manipulation component of a grasp. The role of both types of object information in planning a grasp is examined. Specifically, questions directed at the degree of planning by each component, their independence from one another, as well as their mode of planning (serial vs. parallel) are addressed. Two experiments employed a precueing paradigm to manipulate the type of information available prior to movement onset. Variables examined were the location of an object (left/right), its shape (sphere/dowel), as well as its distance from the hand. The primary measure of interest was reaction time to a "go" signal. The kinematics of the ensuing movements were also analyzed. Sizable reaction time costs were found when either type of information was precued ambiguously or incorrectly. Such costs illustrate that both extrinsic and intrinsic object parameters are critical for planning a grasp, supporting the active participation of both components in planning. The overall pattern of reaction time results implies that the arm transport channel is responsible for 'sketching out' an overall plan of action upon which the plan for object manipulation 'rides.' The absence of an interaction between extrinsic and intrinsic parameters, furthermore, suggests that the two channels are functionally independent. The additive effects of extrinsic and intrinsic parameters, finally, is evidence for a serial mode of planning by the two channels. The kinematics of the movements support findings from the literature, and suggest that movements are not time-scaled variations of a prototypical movement. They also reveal that the arm transport component of the movement is affected by both extrinsic and intrinsic object properties; the object manipulation component, on the other hand, appears only sensitive to intrinsic object properties.
10

Disruptions of the Oxytocin System Impacts Aggressive Behavior and Neuronal Activation in Adult Mice

Vadala, Christopher P. 27 May 2021 (has links)
No description available.

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