Dynamical principles in neuroscience

Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?This work was supported by NSF Grant No. NSF/EIA-0130708, and Grant No. PHY 0414174; NIH Grant No. 1 R01 NS50945 and Grant No. NS40110; MEC BFI2003-07276, and Fundación BBVA

Nação legal consciousness and its contribution to the seventeenth-century Dutch Republic debate on slavery and the slave trade

In the seventeenth century, some conversos living throughout Western Europe, who had been either trained in the School of Salamanca or influenced by it, came to the Dutch Republic in search of religious freedom, where they reverted to the open practice of the Jewish tradition. A select few of them became scholars of rabbinic jurisprudence, while retaining their knowledge of Christian theology. As residents and foreigners in the Dutch Republic, rabbis and philosophers synthesized Greek philosophy, Iberian Roman law, rabbinic reasoning, and Jewish and Christian philosophy, in light of the socioeconomic context of the Dutch Republic, to produce literature on behalf of reverted Jews. At the bedrock of Nação legal consciousness lies the jurisprudence of the Nação in seventeenth-century Amsterdam. The main focus of this research project is on the pressing issue: How did the Nação in seventeenth-century Amsterdam contribute to the legal-political discussions of ius naturae et gentium in the Amsterdam-Dutch Republic debate on slavery and the slave trade? While many have undertaken research on the development of the ius naturae et gentium, the contribution of the Sephardim in Amsterdam is insufficiently researched. The aim of this dissertation is to add to the discussion by examining the seventeenth-century Portuguese Hebrew Nation in the Dutch Republic and its colonies, whose ideas of servitus, dominium and libertas were central to the justification of the Dutch Atlantic slave trade, as participants in, and contributors to the law of nature and nations. The goal is to reveal how the Nação in seventeenth-century Amsterdam participates in and contributes to the thinking, reasoning, and arguing about slavery and the slave trade, via the language, concepts, and notions of the time, which was dominated by the language of ius naturae et gentium

Assessing Quantitative Reasoning in a Ninth Grade Science Class Using Interdisciplinary Data Story Assignments

In a data-driven world, it is necessary that students graduate from high school quantitatively literate, with the ability to interpret quantities within a context to make informed decisions for their lives. A critical component of science learning is developing the ability to make sense of data, critically evaluate it, and effectively communicate scientific ideas. The purpose of this study is two-fold: 1) to investigate how 9th grade students in an Earth Science class use quantitative reasoning (QR) skills when constructing evidence-based scientific explanations during Data Story assignments and 2) to provide teachers with supports to incorporate Data Stories into their curriculum. A Data Story is an interdisciplinary, scaffolded written argumentation assignment that requires students to analyze authentic, real-world scientific data and draw their own conclusions. In doing so, students integrate several discrete skills to synthesize an argument that is supported by evidence. Quantitative and qualitative results were used to investigate affordances and challenges students face when constructing a Data Story, what QR skills they use in the process, and what aspects of QR are challenging for them. Two evidence-based learning progressions provided the foundation for the development of two rubrics to score the student Data Stories quantitatively. Four student interviews analyzed using Grounded Theory provided qualitative insight into the role of QR in evidence-based explanations. Results suggest students enjoyed the Data Story assignments, which exposed them to a range of graph-types and data literacy skills. However, students seemed to struggle to develop appropriate evidence to support a claim in the Claim-Evidence- Reasoning (CER) framework and may need additional supports in this area. Further analysis with the QR Rubric and student interviews revealed some aspects of QR that may be hindering science learning and the development of evidence-based reasoning including: 1) not reasoning about variables in the context of a dataset 2) looking only for a correlation or difference and 3) not using quantitative language. These are aspects teachers should consider when implementing Data Story assignments in their own classrooms as a way to enhance students’ abilities in developing appropriate evidence to support a claim

Assessment Of Reliability And Stability Of Various Visual Search Parameters

Research in social science has been on a continuous self-correcting path as scientists find new ways to look at old problems. Recent technology has given us the ability to perform compounded calculations in a fraction of previous times while recording complex measurements with greater degrees of precision. While this is helpful regarding corporeal measures, quantifying cognition is still a difficult task. Recently, many computer-aided eye tracking devices have been developed and used to validate visual search theories. However, few inquiries have been made assessing the reliability and stability of these methods. This study assessed the reliability and stability of visual attention tasks using the Gazepoint eye-tracker. Visual scanning behaviors of 46 participants were recorded to provide evidence of reliability and stability of four measurement outcomes: (1) total number of fixations, (2) latency to first fixation, (3) total time attending, and (4) total number of switches between areas of interest. All visual scanning measures were found to be stable across stimuli and trials with total number of fixations and total fixation time being the most reliable visual scanning measure. These findings can afford better visual theory development and predictions of subsequent development outcomes

The Jewish Prohibition Against Wastefulness: The Evolution of an Environmental Ethic

Bal tashḥit, the Jewish prohibition against wastefulness and destruction, is considered to be an environmental ethic by Jewish environmentalists. This dissertation investigates whether this prohibition has the historical basis to be considered an environmental principle, or whether its environmental interpretation is mainly a contemporary development. To this end, the study uses the methodology of tradition histories. This research critically examines the conceptualisation of bal tashḥit as it develops throughout history. The dissertation traces the evolution of bal tashḥit through the examination of relevant passages dealing with wastefulness and destruction in Hebrew Scripture, rabbinic literature, halakhic codes, responsa, the accompanying commentary traditions, as well as the works of scholars in the field of Religion and Environment. It highlights the important stages in the development of the prohibition, notes the most influential scholars, and uncovers the critical vocabulary that emerges. The most significant finding of this research is that in the earliest stages of development (c. 1st-2nd centuries C.E.), the prohibition against wastefulness was conceptually linked with the prohibition against self-harm. This connection was rejected by sages of the Talmud (3rd-6th centuries C.E.) who asserted that these prohibitions are qualitatively different from one another. Ultimately, the separation between the two prohibitions became the predominant view, and their connection disappeared almost entirely from Jewish literature. When combined, these prohibitions create an environmental ethic: wastefulness and destruction are harmful to oneself; and in environmental terms: to harm the environment is to harm oneself