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Functional Differentiation Between the Left and Right Hemisphere for a Sub-Region of Wernicke's Area is Revealed with fMRI-Guided, Single-Pulse TMS.
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During the past two decades, studies of neural organization have been bolstered by the addition of functional and structural brain-imaging techniques capable of localizing and correlating brain activity to cognitive functions. With potential clinical applications abound, localizing language-related activity prior to neurosurgery is an interest shared by both neuroscientists and neuroradiologists who are interested in protecting essential language regions in neurosurgery candidates. Since imaging is correlative, however, it does not distinguish essential brain activity from supporting and associated activity and therefore cannot be used independently to determine hemispheric language dominance. Transcranial magnetic stimulation (TMS), on the other hand, is a non-invasive technique that stimulates targeted brain regions directly and can therefore inform causative structure/function relationships. The goal of this study is to develop non-invasive techniques that definitively identify hemispheric language dominance. Functional Magnetic Resonance Imaging (fMRI) was used to locate language-related regions in 36 right-handed participants. In most participants, there were two clusters of activation within classic Wernicke's territory. We termed these dorsal and ventral Wernicke's areas. On a separate day, fourteen of the thirty-six participants returned to participate in a single-pulse TMS experiment which targeted dorsal and ventral Wernicke's areas and their right-sided homologues. Picture naming latency was decreased following TMS of left-sided dorsal and ventral Wernicke's areas as well as right-sided ventral Wernicke's homologue. No effect was observed following TMS of dorsal Wernicke's homologue. These results highlight the advantages of using cross-modal imaging techniques by providing direct evidence in support of modern theories of neural language organization that propose a bilateral sub-region of Wernicke's area involved in phonological processing, and a unilateral left-sided component involved in integration and relay of semantic information to other cortical regions.
Subgroup Differences and Predictive Ability of Psychometric and Neuropsychological Intelligence Measures
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Researchers recognize that the current models of intelligence are insufficient at making causal connections between the intelligence measure and intelligent behavior. Different approaches to intelligence are under investigation to incorporate within current models of intelligence and include psychometric, neuropsychological, and cultural components. Currently there is a lack of research that incorporates both psychometric and neuropsychological intelligence measures in a predictive model of performance. The purpose of the current study is three-fold. The first objective is to test the predictive relationships of neuropsychological and psychometric intelligence batteries, an alternative psychometric intelligence assessment, and a personality measure in relationship to academic performance. The second objective is to examine racioethnic and gender subgroup mean differences on all predictors of performance. Subgroup mean differences, which can lead to adverse impact, have been found on a variety of verbal and nonverbal intelligence assessments (Hough, Oswald, & Ployhart, 2001). Research has demonstrated that performance differences are often moderated by the type of measure used which also raises concerns about the construct validity of psychometric intelligence assessments. The third objective of the research is to examine the construct validity of neuropsychological intelligence, traditional psychometric intelligence, and alternative psychometric intelligence. There is little empirical evidence which demonstrates that differences in cognitive functioning in the brain result in differences in scores on psychometric assessments. That is, there are few links (i.e., construct validity evidence) connecting cognitive functioning to intelligent performance on psychometric assessments. Hypotheses pertaining to prediction of different measures, subgroup mean differences, and statistical relationships among the intelligence measures were tested. The results indicate that the neuropsychological intelligence battery was the only significant predictor of academic performance. All intelligence measures exhibited subgroup mean differences, however they were smaller compared to what is typically reported in the literature. The Black/African American mean score on the neuropsychological battery was one-third of a standard deviation below the White/Caucasian mean score, and Hispanics demonstrated minimal mean score differences compared to White/Caucasians. Additionally, construct validity evidence emerged for the intelligence measures. A discussion of the findings including their implications is included.
Assessing the Effects of Behavioral Skills Training on Adult Teaching Responses, Learner Acquisition, and Learner Disruptive Behavior Across Responses and Instructional Skill Sets
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Behavioral Skills Training (BST) is a teaching package consisting of instructions, feedback, modeling, and rehearsal that has been effective for training staff to provide intervention to people with developmental disabilities. The purpose of the current study was to assess: (a) whether prior studies demonstrating the effectiveness of BST could be systematically replicated in a variety of teaching procedures, (b) whether the instructional skills that staff acquired during training on one response generalized to a variety of instructional programs, (c) whether positive changes in staff performance corresponded to positive behavior change in learners and (d) whether positive changes in learner behavior generalized to novel programs. Results systematically replicated and extended prior studies by demonstrating that BST resulted in positive behavior change across staff, learners, instructional programs, and various types of teaching skills. Further, for all types of instructional procedures staff displayed generalization of teaching skills to novel responses and learners displayed increases in correct responding, indicating that BST is an effective and efficient intervention procedure.
Rules are Made to be Broken: Multisensory Interactions at Two Stages of Cortical Processing
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Research over the past few decades has illuminated the multisensory brain. While information from the various senses is first processed in segregated channels, this segregation is more the exception than the norm. It has now been convincingly demonstrated that the senses can begin to interact at the onset of processing in early sensory cortices (e.g., Foxe et al., 2000; Foxe & Schroeder, 2005; Lakatos, Chen, O'Connell, Mills & Schroeder, 2007; Lakatos, Karmos, Mehta, Ulbert & Schroeder, 2008; Lakatos et al., 2009; Molholm et al., 2002; Murray et al., 2005). These multisensory interactions continue as environmental stimuli proceed to be processed in higher-order cortical areas, but the rules and outcomes change. The following experiments were designed to investigate the neuroanatomic and neurophysiologic underpinnings of multisensory interactions at two stages of processing: (1) an earlier stage at the onset of cortical processing, where multisensory interactions contribute to detection and selection, and (2) a later stage of cortical processing, where multisensory features are combined into a coherent object. We also focus on the rules that govern these interactions. Basic rules for multisensory integration were first established in the cat superior colliculus (Meredith & Stein, 1983; Meredith & Stein, 1986; Meredith, Nemitz & Stein, 1987). These rules state that multisensory integration is more likely when (1) the unisensory components arise from approximately the same location (i.e., the spatial rule), (2) the unisensory components occur at approximately the same time (i.e., the temporal rule), and (3) the unisensory components elicit weak responses when they are presented in isolation (i.e., the rule of inverse effectiveness). While these seminal rules have provided useful guidelines, more recent research has shown that they are not applicable to all multisensory interactions (e.g., Murray et al., 2005; Stein, London, Wilkonson & Price, 1996; Teder-Sälejärvi, Di Russo, McDonald & Hillyard, 2005; Van der Burg et al., 2008a). Here we provide further evidence that the rules for multisensory integration, as well as its outcomes, depend on several factors, including the stage of cortical processing and the observer's strategic goals.
From property abandonment to predatory equity: Writings on financialization and urban space in New York City
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Financial markets, actors and imperatives are increasingly central to today's global capitalism, even in areas of the economy traditionally distinct from finance, such as real estate. This financialization changes the role of mortgage capital in urban space from building place-bound wealth to facilitating the extraction of value from place. This dissertation addresses questions about how financialization operates in the rental market, specifically its relation to: earlier processes of urban disinvestment, ongoing social and political struggles around urban space, the meaning of home and social reproduction. These questions correspond to broader theoretical debates about the contingent relationship between today's urban context and landscapes inherited at the end of the 1970s, the constraints and possibilities for today's community-based organizations and the consequences of finance's permeation into everyday life. Using qualitative, archival and geographic methods, the research design revolves around a long temporal frame beginning with the 1970s urban crisis of property abandonment and continuing through the present. Geographic data was used to analyze relationships between property abandonment and private equity real estate investment. Archival data and interviews with veteran (n=11); mid-career (n=5); and emerging (n=9) nonprofit professionals provided insight on community responses to disinvestment and financialization. Focus groups (N=5) with tenants (n=27) addressed social and psychological consequences of financialization. Today's financialization of housing shapes uneven geographies of power: finance can make itself felt in property, but is often beyond the reach of community organizations and the city. Concentrated in low-income, minority neighborhoods, investors' financial risks undermined tenants' ontological security and social reproduction. Community organizations' development of discursive, data-driven and spatial tactics speaks to the political possibilities of contemporary community practice to contest financialization. The findings are relevant to efforts of community organizations to contest urban inequality, concerns about planning economically sustainable cities and policy approaches to affordable rental housing. This study contributes to research on geographies of financialization; in particular it responds to the need for critical attention to the socially and spatially uneven nature of processes associated with financialization of the domestic.
Multimodal Emotion Perception in Borderline Personality Disorder
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Borderline personality disorder (BPD) is a chronic disorder characterized by pervasive difficulties in the emotion regulation system. While it is clear that individuals with BPD frequently exhibit intense emotional reactions, lack abilities to effectively manage such emotions, and often engage in serious maladaptive behaviors as a consequence of intense emotions, many aspects of the process by which this sequence occurs are not well understood. One crucial aspect of emotion regulation is the processing and perception of cues from the environment. To date, processing of emotional cues in individuals with BPD has been understudied. Therefore, the purpose of this paper is twofold. First, a thorough overview of the literature on the development of both emotion regulation and emotion processing will be presented. Next, theories linking emotion processing, emotion regulation and the development of BPD will be critically analyzed. Finally, a study designed to investigate perception and processing in individuals with BPD versus a healthy control group will be presented, and the results will be discussed. The study presented is the first known study to not only examine emotion perception in BPD using a unitary measure of facial and auditory emotion perception, but to also compare the emotion perception measure to a measure of social perception.
Perception of Emotion across the Adult Life Span in Three Communication Channels
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The current study examined age-related differences in emotion perception skills in 116 healthy adults, aged 20-89. Subjects completed identification and discrimination emotion perception tasks involving positive and negative emotion stimuli in three channels of communication: facial, lexical, and prosodic. The emotion tasks were from the New York Emotion Battery (NYEB; Borod, Obler, & Welkowitz, 1992). Participants were screened for cognitive functioning, psychiatric and neurological history, dementia, and perceptual skills, using procedures from the NYEB, and were matched across age groups for demographic variables. Associations among demographic characteristics (gender, ethnicity, and educational level), nonemotional control tasks from the NYEB, and emotion perception tasks were examined using multiple regression. Age was also included in these analyses in order to directly evaluate the effects of age and the effects of these other variables. We examined age-related differences in emotion perception, in general, and explored whether age-related differences varied as a function of communication channel and valence in the context of the general decline with age hypothesis, the right hemi-aging hypothesis, and the positivity bias. In light of research showing that relationships among cognitive functions become more homogeneous, or less specialized, with age, we examined relationships among the three emotion channels within the context of the hemispheric asymmetry reduction with old age (HAROLD; Cabeza, 2002) and dedifferentiation models. For all three channels of communication, older adults performed worse than younger adults. Years of education predicted performance for lexical tasks only. Age emerged as the most significant predictor of performance on emotion perception tasks, and neither ethnicity nor gender generally emerged as significant predictors of performance. Interrelationships among channels were stronger for older adults (i.e., 70- and 80-year-olds) than for their younger cohorts. Results are discussed in the context of neuropsychological and psychosocial theories of aging and emotion. The finding that older groups encountered significantly more difficulty with emotion perception tasks is consistent with the general decline hypothesis and aspects of the right hemi-aging hypothesis. There was no positivity bias demonstrated among the older participants. Abilities within participants were more homogeneous in older age groups, suggesting that emotion perception skills become less specialized with age.
Peer Pyramidal Training: Effects on Direct Support Staff Teaching Skills and Generalization of Trainer Skills
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Training is important to ensuring that staff members have the skills they need to provide effective and quality services to individuals with intellectual disabilities, but human services agencies often have limited resources to devote to training. The experimenter used two concurrent multiple-probe-across-participants designs to assess the effectiveness of a peer pyramidal training program on staff performance in a day habilitation program for adults with psychiatric disorders and intellectual disabilities. In the first design, the experimenter assessed the teaching skills of peer trainers as they taught their co-workers to implement (1) responses in which the trainers received specific instruction in how to teach (training responses) and (2) responses in which the trainers had no instruction in how to teach to others (generalization responses). In the second design, the experimenter assessed the effect of the peer training program on the staff members' ability to use positive reinforcement and prompting procedures to teach consumers and to document behavioral incidents. Peer trainers improved their use of teaching skills while instructing staff on training responses as a function of the training program. Further, these effects generalized to the instruction of staff on the generalization responses. All staff improved their performance on all responses that the peer trainers taught them following implementation of the pyramidal training program. All participants reported a high degree of social validity. These results extend the research on pyramidal training and suggest that, for human services agencies with widespread budgetary constraints, direct support professionals may be able to train one another effectively.
SOCIAL ASPECTS OF DEVELOPING AND SUSTAINING VOLUNTARILY REDUCED CONSUMPTION ACTIVITY IN NEW YORK CITY
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This dissertation examines the social aspects of voluntarily reduced consumption activity using the principles of cultural historical activity theory. Voluntarily buying less is viewed as ongoing interactive social process that is initiated and sustained as individuals engage with their surroundings. Data was collected from 320 online survey respondents living in the New York City Metro area, followed by a purposeful sampling of 24 participants for in-person, follow up interviews. Interviews revealed the social contextual influences on initiating voluntarily reduced consumption activity. For example, family experiences, personal life changes, and historical events played a role in individuals' choice to voluntarily buy less. Individuals who choose to voluntarily reduce how much they buy experience both social supports and barriers to their activity. Many interview respondents treated voluntarily buying less as a sensitive topic of conversation, not to be openly discussed with others who did not hold the same opinions or values. Those participants adopted techniques to determine who the topic could be broached with while avoiding conflict with those who it may cause problems. Having social support and resources made a noteworthy difference in the viability of adopting many practices, such as reducing the amount of gifts exchanged at the holidays or acquiring used goods instead of buying something new. Social pressure to consume or support for buying less changed based upon specific situations, environments, and individuals with whom the respondent was interacting. Significant others were an important source of support for voluntarily buying less through actions such as sharing responsibility, reinforcing practices or providing skills. Having children presented particular challenges to buying less, as well as an opportunity to pass along one's values and practices. Family and friends were often a resource for skills and information for practices including repairing goods or doing things for oneself. However, friendships that were not supportive were a particular sore spot for some interview participants. Making compromises, not talking about their values and practices, or reducing the amount of time they spent with their friends was a source of strain, anger, and feelings of social isolation. While a few developed new friendships that supported their buying less values, others enacted conflict-reducing practices in order to negotiate social interactions with their friends. Interview participants' choice of employment influenced how much pressure they felt to maintain social norms and communicate status through purchasing of goods such as clothing and technology. The impact of living in New York City was very noticeable when interview participants talked about the support they received from their participation in local social groups, organizations, and communities. Some interview respondents felt their voluntarily reduced consumption activity may influence others. However, not all participants were motivated by the thought that their voluntarily reduced consumption activity was making an impact on a larger scale. A few even feel that what they are doing may have a negative impact on others.
PROBLEM SOLVING THROUGH TOOL USE IN ASIAN ELEPHANTS
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Spontaneous problem solving without evident trial and error behavior has been referred to as insight. Surprisingly, elephants, thought to be highly intelligent, have failed to exhibit insightful problem solving in previous cognitive studies. I conducted ten experiments investigating problem solving through tool use on three Asian elephants. Experiment 1 was designed to test means-end recognition. Trays with food placed on one end were positioned outside the bars of the elephants' stalls. Each of the elephants pulled the tray, showing understanding of the means-end relationship. In Experiments 2 and 3, I tested if elephants would use sticks as tools to reach food trays placed just beyond their trunk reach or use sticks to knock out-of-reach fruit from an artificial tree. None of the elephants employed sticks to accomplish either task. A chain pulling problem to attain food through a multi-step solution was presented in Experiment 4. All elephants solved the problem and one completed the task immediately, suggesting insightful problem solving. In Experiment 5, I investigated if elephants, when presented with different types of potential tools, a movable platform and sticks, would show tool use to reach food suspended overhead, out-of-reach. Without prior trial and error behavior, a 7-year-old male showed spontaneous problem solving by moving a large plastic cube, on which he stood, to acquire the food. In Experiments 6-8, I tested if the elephant would generalize this ability to other positions and objects, which he demonstrated. In Experiment 9, I examined if tool use with sticks differed in relation to suspended food or an object. No difference was found. Social learning was tested in Experiment 10 by having one elephant demonstrate the solution to a tool use problem while a second elephant observed. No social learning was exhibited. The elephant's behavior in experiments 5-8 was consistent with the definition of insightful problem solving. Previous failures to demonstrate this ability in elephants may have resulted not from a lack of cognitive ability but from the presentation of tasks requiring trunk-held sticks as potential tools, thereby interfering with the trunk's use as a sensory organ to locate the targeted food.