Investigations into the Neural Basis of Structured Representations

The problem of how the brain encodes structural representations is investigated via the formulation of computational theories constrained from the bottom-up by neurobiological factors, and from the top-down by behavioral data. This approach is used to construct models of letter-position encoding in visual word recognition, and of hierarchical representations in sentence parsing. The problem of letter-position encoding entails the specification of how the retinotopic representation of a stimulus (a printed word) is progressively converted into an abstract representation of letter order. Consideration of the architecture of the visual system, letter perceptibility studies, and form-priming experiments led to the SERIOL model, which is comprised of five layers: (1) a (retinotopic) edge layer, in which letter activations are determined by the acuity gradient; (2) a (retinotopic) feature layer, in which letter activations conform to a monotonically decreasing activation gradient, dubbed the locational gradient; (3) an abstract letter layer, in which letter order is encoded sequentially. (4) a bigram layer, in which contextual units encode letter pairs that fire in a particular order; (5) a word layer. Because the acuity and locational gradients are congruent to each other in one hemisphere but not the other, formation of the locational gradient requires hemisphere-specific processing. It is proposed that this processing underlies visual-field asymmetries associated with word length and orthographic-neighborhood size. Hemifield lexical-decision experiments in which contrast manipulations were used to modify activation patterns confirmed this account. In contrast to the linear relationships between letters, a parse of a sentence requires hierarchical representations. Consideration of a fixed-connectivity constraint, brain imaging studies, sentence-complexity phenomena, and insights from the SERIOL model led to the TPARRSE model, in which hierarchical relationships are represented by a predefined distributed encoding. This encoding is constructed with the support of working memory, which encodes relationships between phrases via two synchronized sequential representations. The model explains complexity phenomena based on specific proposals as to how information is represented and manipulated in syntactic working memory. In contrast to capacity-based metrics, the TPARRSE model provides a more comprehensive account of these phenomena

Personal Factors Influencing US Travelers’ Sentiments Toward Travel Policies to Cuba

The United States and Cuba have navigated a strained political and economic relationship over the past sixty years; the tone of the relationship is in flux according to Cuban and US leadership, and most recently, COVID-19. Anticipating US travelers’ sentiments towards access to Cuba is more crucial now because of resulting policies playing out within the intersection of the shifting dynamics of the virus and the tumultuous political climate within the US. This study identified the personal factors that influence US travelers’ sentiment towards the US trade embargo and travel restrictions to Cuba. Results reveal that respondents with higher educational achievements, Spanish-speaking ability, Cuban knowledge, and those well-traveled, were likely to oppose the embargo and support access to Cuba

Hitting a Moving Target: Resource Access in a Mobile World

http://deepblue.lib.umich.edu/bitstream/2027.42/94444/1/Hitting_a_Moving_Target_Resource_Access_in_a_Mobile_World.pd

The Impact of Microenterprise Development Training on Low-Income Clients

The study reported here examined the impact of microenterprise development (MED) programs on low-income individuals using a case study of 140 clients of the Vermont Micro Business Development Program who participated in a statewide telephone survey. The study also examined variables that are associated with change in client reliance on public assistance. Outcomes achieved include: access to capital, positive attitude changes, business start up and growth, job creation, increased household income, decreased reliance on public assistance, and satisfaction with services. Significant relationships were found between certain client characteristics and outcomes and decreased reliance on public assistance

U.S. Fossil Fuel Resources: Terminology, Reporting, and Summary

This report describes the characteristics of fossil fuels that make it necessary to use precise terminology (oil, natural gas, and coal), summarizes the major terms and their meanings, and provides a brief summary of U.S. endowment of fossil fuels and the relationship between the U.S. fossil fuel energy endowment and those of other nations

U.S. Fossil Fuel Resources: Terminology, Reporting, and Summary

This report describes the characteristics of fossil fuels that make it necessary to use precise terminology, summarizes the major terms and their meanings, and provides a brief summary of the United States’ endowment of fossil fuels and the relationship between the U.S. fossil fuel energy endowment and those of other nations