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Intelligence and neural activation : a test of the relationship between the neural efficiency hypothesis and repetition suppression
No full texthonors thesisCollege of Social & Behavioral SciencePsychologyMatthew J. EulerThe Neural Efficiency Hypothesis (NEH) states that individuals with higher measured intelligence exhibit less neural activation on relatively simple tasks compared to those with lower intelligence (Haier et al., 1988). Furthermore, this phenomenon may interact with repetition suppression, or the reduction of neural activity following repeat stimulus exposure (Grill-Spector et al., 2006). The current study examined the relationship between intelligence and event-related EEG amplitudes and latencies during the third of three task conditions, a visual repetition paradigm. Full Scale IQ (FSIQ) scores from the Wechsler Adult Intelligence Scale III (WAIS-III; Wechsler, 1997) were collected on 30 participants, 18 of whom had sufficient numbers of EEG trials for further analysis (FSIQ: M = 111.56, SD = 13.28, range = 91 to 131). During EEG recording, participants were asked to respond to randomized line drawings representing one of three stimulus conditions from the previous two tasks: Repeated stimuli, Once-viewed, and Novel stimuli. Time-frequency analyses were conducted to identify peak phase-locked activity in the theta (4-7 Hz) and alpha (8-12 Hz) bands between 0 and 500 milliseconds poststimulus. Results demonstrated no significant effects of IQ or stimulus condition on peak theta and alpha amplitudes. However, difference scores between Novel and Once-viewed conditions in peak theta latency showed a strong positive correlation with IQ (r[16] = .712, p < .01). These findings appear consistent with the NEH in suggesting that higher IQ individuals may process previously-seen stimuli more efficiently than lower IQ individuals, as evidenced by shorter peak latencies relative to stimulus onset
Neurotrophic Factor Genetics of Cognitive Progression and Neuropsychiatric Symptom Presentation in Alzheimer\u27s Disease and Related Disorders
Get PDFThe Cache County Study on Memory in Aging (CCSMA) and subsequent Dementia Progression Study (DPS) were two research studies that took place in Cache County, Utah. These studies followed 5092 participants aged 65 or older for approximately 12 years and looked at risk and protective factors for dementia, including Alzheimer’s disease. One of the factors investigated was genes that are known to influence brain health, such as brain-derived neurotrophic factor (BDNF), a protein found in the brain that helps with the survival of brain cells.
BDNF genes have been shown to be associated with Alzheimer’s disease and related dementia (ADRD) risk, but little is known about the influence these genes have after dementia is diagnosed. The current study looked at how BDNF related genes were associated with learning and memory abilities (i.e. cognitive ability) and problematic behaviors (e.g. delusions, agitation/aggression, anxiety) in individuals from the CCSMA and DPS who were diagnosed with ADRD. This research is important to help understand what may contribute to often-seen differences in dementia progression and help inform possible treatment decisions.
The results of the current project showed that BDNF genes influenced both progression of cognitive difficulties and problematic behaviors in individuals with ADRD. Additionally, it was shown that many of these effects depended on the sex of the individual, such that men and women progressed at different rates and were influenced by different BDNF related genotypes. These results provide evidence of the influence of BDNF genes after dementia diagnosis and highlights the need to investigate contributing factors related to the sex of the individual. Targeted medication or behavioral treatment of dementia that both improves BDNF function in the brain, as well as mitigates any sex-related effects, may also be another avenue for future research
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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