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Temporal dynamics of visual representations in the infant brain
No full textDevelopmental Cognitive Neuroscience, Volume 45, October 2020, Article number 100860.Tools from computational neuroscience have facilitated the investigation of the neural correlates of mental representations. However, access to the representational content of neural activations early in life has remained limited. We asked whether patterns of neural activity elicited by complex visual stimuli (animals, human body) could be decoded from EEG data gathered from 12−15-month-old infants and adult controls. We assessed pairwise classification accuracy at each time-point after stimulus onset, for individual infants and adults. Classification accuracies rose above chance in both groups, within 500 ms. In contrast to adults, neural representations in infants were not linearly separable across visual domains. Representations were similar within, but not across, age groups. These findings suggest a developmental reorganization of visual representations between the second year of life and adulthood and provide a promising proof-of-concept for the feasibility of decoding EEG data within-subject to assess how the infant brain dynamically represents visual objects
Sign for free meals
No full textSign on a lamppost for free to-go meals provided by Ebenezers Coffeehouse
The cerebellar cognitive affective/Schmahmann syndrome: a task force paper
No full textCerebellum, Volume 19, Issue 1, 1 February 2020, Pages 102-125.Sporadically advocated over the last two centuries, a cerebellar role in cognition and affect has been rigorously established in the past few decades. In the clinical domain, such progress is epitomized by the “cerebellar cognitive affective syndrome” (“CCAS”) or “Schmahmann syndrome.” Introduced in the late 1990s, CCAS reflects a constellation of cerebellar-induced sequelae, comprising deficits in executive function, visuospatial cognition, emotion–affect, and language, over and above speech. The CCAS thus offers excellent grounds to investigate the functional topography of the cerebellum, and, ultimately, illustrate the precise mechanisms by which the cerebellum modulates cognition and affect. The primary objective of this task force paper is thus to stimulate further research in this area. After providing an up-to-date overview of the fundamental findings on cerebellar neurocognition, the paper substantiates the concept of CCAS with recent evidence from different scientific angles, promotes awareness of the CCAS as a clinical entity, and examines our current insight into the therapeutic options available. The paper finally identifies topics of divergence and outstanding questions for further research
Person rides bike past shuttered restaurant
No full textA person rides a bicycle in the bike lane past the Le Diplomat restaurant. The restaurant windows are covered. The sign above the windows read 'DEJEUNER-DINER-SOUPER' and 'BIERES PRESSION'
The low glutamate diet effectively improves pain and other symptoms of gulf war illness
No full textNutrients, Volume 12, Issue 9, September 2020, Article number 2593, Pages 1-15.Gulf War Illness (GWI) is a multisymptom disorder including widespread chronic pain, fatigue and gastrointestinal problems. The objective of this study was to examine the low glutamate diet as a treatment for GWI. Forty veterans with GWI were recruited from across the US. Outcomes included symptom score, myalgic score, tender point count, dolorimetry and the Chalder Fatigue Scale. Subjects were randomized to the low glutamate diet or a wait-listed control group, with symptom score being compared after one month. Subjects then went onto a double-blind, placebo-controlled crossover challenge with monosodium glutamate (MSG)/placebo to test for return of symptoms. Symptom score was compared between diet intervention and wait-listed controls with an independent t-test and effect size was calculated with Cohen’s d. Change scores were analyzed with Wilcoxon Signed Rank tests. Crossover challenge results were analyzed with General Linear Models and cluster analysis. The diet intervention group reported significantly less symptoms (p = 0.0009) than wait-listed controls, with a very large effect size, d = 1.16. Significant improvements in average dolorimetry (p = 0.0006), symptom score, tender point number, myalgic score and the Chalder Fatigue Scale (all p < 0.0001) were observed after the 1-month diet. Challenge with MSG/placebo resulted in significant variability in individual response. These results suggest that the low glutamate diet can effectively reduce overall symptoms, pain and fatigue in GWI, but differential results upon challenge suggest that other aspects of the diet, or underlying differences within the population, may be driving these changes. Future research is needed to identify potential nutrient effects, biomarkers, and underlying metabolic differences between responders and non-responders
Neural and Computational Mechanisms of Cognitive Flexibility
No full textRecent studies have used one-trial-back decision policies (Win-Stay/Lose-Shift) and measures of reinforcement learning (RL, e.g. learning rate) to explain decision-making in two-armed bandit tasks. In many of these studies, outcomes reverse after one option is selected repeatedly (e.g. 8 in a row), and the primary measure of performance is the number of reversals completed. However, a confound exists between the number of reversals and Win-Stay likelihood. An alternative design reverses cue- or action-outcome associations over fixed blocks of trials. We used this blocked design and tested rats in a spatial two-armed bandit task. We analyzed choice behavior as a function of reward certainty and using Win-Stay/Lose-Shift (WSLS) metrics and Q-learning, an RL algorithm. We found that WSLS policies remain stable with increasing reward uncertainty, while choice accuracy decreases. Within test sessions, learning rates increased as rats adapted their strategies over the first few reversals but inverse temperature, a measure of choice randomness, remained stable. The OFC is commonly implicated in reversal learning, and we found that muscimol inactivation of the medial orbital cortex (mOFC) increased perseveration toward the previously best option and decreased negative feedback sensitivity. We then examined the role of noradrenaline neurotransmission in bandit performance and found yohimbine (2mg/kg) decreased rats’ sensitivity to positive feedback, leading to decreases in accuracy and increase in choice randomness. These effects are partially dependent on α2-noradrenergic receptors in OFC. Finally, we demonstrate a correspondence between reward schedule, WSLS policies and RL metrics in a task design that is free of the confound between Wins and reversals, and that the noradrenergic influence of mOFC on WSLS policy is dissociable from the region’s general role in cognitive flexibility.NeurosciencesPsychologyDegree Awarded: Ph.D. Psychology. American Universit
THREE ESSAYS ON GENDER, UNCONDITIONAL CASH TRANSFERS AND TIME USE
No full textGender equality – a Sustainable Development Goal, may not be achieved without recognizing the work females are already performing. This dissertation gives deeper insights to measurement issues of female labor force participation, intra-household hierarchy within females in multi-generational set up and the long-term effect of unconditional cash transfers on attitudes of the beneficiaries. Time Use surveys provides a unique opportunity to accurately measure the time allocated to unpaid reproductive work (URW) and labor market work, circumventing any self-reporting bias. In my first essay, using Pakistan Time Use, I identified invisible labor force, 88 percent of which constitutes of women. Further, I examine the effect of husband’s earning potential and his adherence to patriarchal norms on wife’s probability to participate in invisible labor force. I develop a theoretical model to examine the trade-off between social cost of wife’s labor market work and its financial gains to the household. My findings show the more conservative the husband is, higher is the probability that wife will participate in invisible labor. Next, I analyze the effect of access to public infrastructure (on-site water sources and natural gas for cooking) on the time allocated to URW of females and how is it reallocated to other welfare enhancing activities. Further, it examines the association between ownership of labor-saving appliances (washing machine and refrigerator) and time devoted to laundry and food preparation respectively employing instrumental variable regression. The findings indicate that intra-household hierarchy within females results in heterogeneous effect of the interventions – increasing the unpaid and reproductive work for daughters-in-law while boosting leisure for mothers-in-law. Moreover, in the households with access to piped water and electricity the ownership of washing machine increases the laundry time by 25 percent while owning a refrigerator attenuates the time allocated to food preparation by 9 percent. Lastly, in the third essay, I employ propensity score weighting and regression adjustment, to examine the impact of unconditional cash transfers (Benazir Income Support Program (BISP)) on aspirations of the adults in Pakistan. Using Pakistan Rural Household Panel Survey 2012-2013, I construct the aspirations index by weighting and aggregating on four dimensions; income, assets, social status and education. I find BISP cash transfers to increase aspirations index of men by 0.23 standard deviations yet for women, it only impacts those belonging to the poorest households, boosting their aspirations by 0.14 standard deviations. Given the global awakening to the salience of female labor force participation, it is imperative to understand the nuanced context-specific issues females face. This dissertation will contribute by providing insights to the underlying intra-household dynamics in a patriarchal society, with high prevalence of multi-generational households and what role social protection programs can play.EconomicsLabor economicsAspirations, Female Labor Market Work, Time Use, Unconditional Cash Transfers, Unpaid WorkEconomicsDegree Awarded: Ph.D. Economics. American Universit
Signs demanding PPE on the National Mall in front of the United States Capitol
No full textSigns demanding personal protective equipment on the National Mall in front of the United States Capitol. Signs read '#GetUsPPE' and 'We Need PPE, protect us and patients
Mass without Participation of the Faithful: a comparison of Canon 813 & 1 of the 1917 Code and Canon 906 of the 1983 Code
No full textRev. Vincent W. Woo.Typescript.Thesis (J.C.L.)--Catholic University of America, 2020.Bibliography: leaves 53-59.Also available in microfilm.Also available in microfiche
