Neural processing of imminent collision in humans

Detecting a looming object and its imminent collision is imperative to survival. For most humans, it is a fundamental aspect of daily activities such as driving, road crossing and participating in sport, yet little is known about how the brain both detects and responds to such stimuli. Here we use functional magnetic resonance imaging to assess neural response to looming stimuli in comparison with receding stimuli and motion-controlled static stimuli. We demonstrate for the first time that, in the human, the superior colliculus and the pulvinar nucleus of the thalamus respond to looming in addition to cortical regions associated with motor preparation. We also implicate the anterior insula in making timing computations for collision events

Representation results for defeasible logic

The importance of transformations and normal forms in logic programming, and generally in computer science, is well documented. This paper investigates transformations and normal forms in the context of Defeasible Logic, a simple but efficient formalism for nonmonotonic reasoning based on rules and priorities. The transformations described in this paper have two main benefits: on one hand they can be used as a theoretical tool that leads to a deeper understanding of the formalism, and on the other hand they have been used in the development of an efficient implementation of defeasible logic.Comment: 30 pages, 1 figur

The psychological-type profile of practising British druids compared with Anglican churchgoers

This study employs psychological-type theory to profile practising British Druids and to compare their profile with that of Anglican churchgoers. A sample of 75 participants at a camp organised by The Order of Bards, Ovates and Druids in celebration of the Mid-Summer Festival completed the Francis Psychological Type Scales. Compared with the profile of 327 Anglican churchgoers previously published by Francis, Duncan, Craig and Luffman, the Druids were significantly more likely to prefer intuition and less likely to prefer sensing. The implications of these data are discussed for understanding the contemporary appeal of Druidry. Overall the Druids prefer introversion (61%), intuition (64%), feeling (56%) and judging (68%)

Embedding Defeasible Logic into Logic Programming

Defeasible reasoning is a simple but efficient approach to nonmonotonic reasoning that has recently attracted considerable interest and that has found various applications. Defeasible logic and its variants are an important family of defeasible reasoning methods. So far no relationship has been established between defeasible logic and mainstream nonmonotonic reasoning approaches. In this paper we establish close links to known semantics of logic programs. In particular, we give a translation of a defeasible theory D into a meta-program P(D). We show that under a condition of decisiveness, the defeasible consequences of D correspond exactly to the sceptical conclusions of P(D) under the stable model semantics. Without decisiveness, the result holds only in one direction (all defeasible consequences of D are included in all stable models of P(D)). If we wish a complete embedding for the general case, we need to use the Kunen semantics of P(D), instead.Comment: To appear in Theory and Practice of Logic Programmin

Doppler Shift Human Detection Using a Microphone Array

From the Washington University Office of Undergraduate Research Digest (WUURD), Vol. 12, 05-01-2017. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Helen Human, Programs Manager and Assistant Dean in the College of Arts and Sciences Mentor: Arye Nehora

Varying problem effort and problem completion rates : an investigation of the interspersal procedure and student assignment choice

The discrete task completion hypothesis suggests that, when given assignments comprised of multiple discrete tasks, completed discrete tasks are reinforcing events (Skinner, 2002). The current experiment consists of two studies investigating the interaction of relative response effort and relative problem completion rates on student assignment choice and ranking behavior. College students participated in Experiment One. In order to enhance the educational validity of the findings from Experiment One, Experiment Two was conducted with sixth-grade students. In Experiment One, college students were exposed to two pairs of mathematics assignments. Assignment Pair A included a high effort assignment containing 18 long 3- digit x 2-digit multiplication problems with all numerals in each problem being equal to or greater than four and a moderate effort assignment that contained nine long problems and nine interspersed moderate 3-digit x 2-digit problems with numerals less than four. Assignment Pair B contained similar assignment sheets, the exception being that the high effort assignment contained six additional I-digit x I-digit problems interspersed following every third 3-digit x 2-digit problem. Analysis of Assignment Set One revealed that students overwhelmingly preferred the moderate effort assignment. Analysis of interaction effects showed that when additional brief problems were added to the high effort assignments, the proportion of students who chose the high effort assignment for homework and ranked it as being less difficult, time consuming, and effortful increased significantly. Results support previous research on effort and the hypothesis that a completed discrete problem may serve as a reinforcing event. Experiment Two was a replication of Experiment One. However, the educational validity was enhanced, as participants were sixth-grade students who were exposed to assignment pairs identical to those of Experiment One. Results were similar to those found in Experiment One. Results from both experiments showed that students were more likely to choose assignments that required less effort to complete. However, when high effort assignments were altered by interspersing additional brief problems, the probability of students choosing the high effort assignment for homework increased significantly. These results support the discrete task completion hypothesis and suggest that educators can increase the probability of student engaging in assigned work by giving them more work. Additionally, logistic regression analysis yielded models of choice behavior similar to those found in previous studies of the matching law (e.g., Baum, 1974). This novel analysis of group data provided additional support for the discrete task completion hypothesis

Evaluating the Effectiveness of a ‘Real‐World’ Shared Reading Intervention for Preschool Children and Their Families: A Randomised Controlled Trial

Background Shared reading interventions can impact positively on preschool children's language development and on their caregiver's attitudes/behaviours towards reading. However, a number of barriers may discourage families from engaging with these interventions, particularly families from lower socio‐economic status (SES) backgrounds. We investigated how families from such backgrounds responded to an intervention designed explicitly to overcome these barriers. Methods In a preregistered cluster randomised controlled trial, 85 lower SES families and their 3‐year‐old to 4‐year‐old children from 10 different preschools were randomly allocated to take part in The Reader's Shared Reading programme (intervention) or an existing ‘Story Time’ group at a library (control) once a week for 8 weeks. Three outcome measures were assessed at baseline and post intervention: (1) attendance, (2) enjoyment of the reading groups and (3) caregivers' knowledge of, attitudes and behaviours towards reading. A fourth − children's vocabulary – was assessed at baseline and 4 weeks post intervention. Results Families were significantly more likely to attend the intervention group and rated it more favourably, compared with the control group. However, there were no significant effects on caregivers' knowledge, attitudes and behaviours or on children's language. Conclusion The intervention was only successful in engaging families from disadvantaged backgrounds in shared reading. Implications for the use, duration and intensity of shared reading interventions are discussed