Bibliography of literature pertaining to the onset,development, and treatment of stuttering during the preschool years

This bibliography consists of clinical, experimental, and theoretical papers pertaining to the onset, development, and treatment of stuttering in children five- years old and younger. It is a downward extension of Silverman, F.H., Bibliography of literature pertaining to stuttering in elementary-school children, Journal of Fluency Disorders, 1978, 3, 87–102.     

“Honey,Won't You Please Stay Home”

The mass return to campus by the mature woman has become commonplace at colleges and universities across the country. According to the Bureau of the Census, almost 800,000 adults 35 years of age and over were enrolled in or attending college in October 1972 and “over half (53 percent) were women” (Young 1973, p. 39), the overwhelming majority of whom were going to college part-time. Many of these women find that their decision to return to school after an extended interruption of their formal education is both serious and significant, changing not only their own values, perceptions, and self-images but also giving rise to stress and change in their relationships with their families. The 1973 report of the National Advisory Council on Extension and Continuing Education concludes with the statement, “Perhaps most importantly, continuing education programs for women have revitalized the idea that the most important kind of learning results in changes in life styles and in self-image and often requires long and difficult struggle” (Mulligan 1973, p. 17). These changes and the consequent long and difficult struggle often prove to be disturbing, disrupting, disabling, or even disastrous.     

Counterexample Search in Diagram-Based Geometric Reasoning

Topological relations such as inside, outside, or intersection are ubiquitous to our spatial thinking. Here, we examined how people reason deductively with topological relations between points, lines, and circles in geometric diagrams. We hypothesized in particular that a counterexample search generally underlies this type of reasoning. We first verified that educated adults without specific math training were able to produce correct diagrammatic representations contained in the premisses of an inference. Our first experiment then revealed that subjects who correctly judged an inference as invalid almost always produced a counterexample to support their answer. Noticeably, even if the counterexample always bore a certain level of similarity to the initial diagram, we observed that an object was more likely to be varied between the two drawings if it was present in the conclusion of the inference. Experiments 2 and 3 then directly probed counterexample search. While participants were asked to evaluate a conclusion on the basis of a given diagram and some premisses, we modulated the difficulty of reaching a counterexample from the diagram. Our results indicate that both decreasing the counterexample density and increasing the counterexample distance impaired reasoning performance. Taken together, our results suggest that a search procedure for counterexamples, which proceeds object-wise, could underlie diagram-based geometric reasoning. Transposing points, lines, and circles to our spatial environment, the present study may ultimately provide insights on how humans reason about topological relations between positions, paths, and regions.     

Navigating in a challenging semiarid environment: the use of a route-based mental map by a small-bodied neotropical primate

To increase efficiency in the search for resources, many animals rely on their spatial abilities. Specifically, primates have been reported to use mostly topological and rarely Euclidean maps when navigating in large-scale space. Here, we aimed to investigate if the navigation of wild common marmosets inhabiting a semiarid environment is consistent with a topological representation and how environmental factors affect navigation. We collected 497 h of direct behavioral and GPS information on a group of marmosets using a 2-min instantaneous focal animal sampling technique. We found that our study group reused not only long-route segments (mean of 1007 m) but entire daily routes, a pattern that is not commonly seen in primates. The most frequently reused route segments were the ones closer to feeding sites, distant to resting sites, and in areas sparse in tree vegetation. We also identified a total of 56 clustered direction change points indicating that the group modified their direction of travel. These changes in direction were influenced by their close proximity to resting and feeding sites. Despite our small sample size, the obtained results are important and consistent with the contention that common marmosets navigate using a topological map that seems to benefit these animals in response to the exploitation of clustered exudate trees. Based on our findings, we hypothesize that the Caatinga landscape imposes physical restrictions in our group’s navigation such as gaps in vegetation, small trees and xerophytic plants. This study, based on preliminary evidence, raises the question of whether navigation patterns are an intrinsic characteristic of a species or are ecologically dependent and change according to the environment.