Survival circuits and risk assessment

Risk assessment (RA) behaviour is unusual in the context of survival circuits. An external object elicits eating, mating or fleeing; but conflict between internal approach and withdrawal tendencies elicits RA-specific behaviour that scans the environment for new information to bring closure. Recently rodent and human threat responses have been compared using ‘predators’ that can be real (e.g. a tarantula), robot, virtual, or symbolic (with the last three rendered predatory by the use of shock). ‘Quick and dirty’ survival circuits in the periaqueductal grey, hypothalamus, and amygdala control external RA behaviour. These subcortical circuits activate, and are partially inhibited by, higher-order internal RA processes (anxiety, memory scanning, evaluation and sometimes — maladaptive rumination) in the ventral hippocampus and medial prefrontal cortex

Behavioural inhibition and valuation of gain/loss are neurally distinct from approach/withdrawal

Gain or omission/termination of loss produces approach; while loss or omission/termination of gain produces withdrawal. Control of approach/withdrawal motivation is distinct from valuation of gain/loss and does not entail learning – making “reward” and “punishment” ambiguous. Approach-withdrawal goal conflict engages a neurally distinct Behavioural Inhibition System, which controls “anxiety” (conflict/passive avoidance) but not “fear” (withdrawal/active avoidance)

Educational drama in the teaching of education for sustainability

In this paper, I describe part of my research project that examines the use of Educational Drama in Education for Sustainability in the upper stages of the primary school (10- and 11-year-olds). Central to the research is a small-scale qualitative research study. Here, I describe the educational focus of the study and outline the methodology. Central to the study was a series of drama lessons (taught by me) based on environmental themes. The lessons link with some of the key aims in Education for Sustainability - to help young people to develop awareness, knowledge and concepts, to encourage positive attitudes and personal lifestyle decisions and to help them to acquire action skills in and for the environment. The locus is within the Scottish education system. A number of key data were generated during the teaching and evaluation of the lessons. These take the form of field notes, children's evaluations of their work and learning, observation schedules, taped interviews with participants and observers and videotapes of the lessons. The analysis of the data is ongoing, but already there is substantial evidence to suggest that the drama was instrumental in helping the children to achieve the learning outcomes set for the lessons. Some of that evidence is presented here. I suggest that the active, participative learning central to drama is particularly useful for allowing children to develop skills in communication, collaboration and expressing ideas and opinions. Also, the immersion in the imagined context and narrative, integral to the 'stories' in the drama, allows the children to feel sympathy for and empathy with people who are affected by environmental issues and problems. In giving the children a context for research and in helping them to plan solutions and to suggest alternatives, the drama allows the participants opportunities to rehearse active citizenship and facilitates learning in Education for Sustainability

Scaling properties of velocity and temperature spectra above the surface friction layer in a convective atmospheric boundary layer

International audienceWe report velocity and temperature spectra measured at nine levels from 1.42 meters up to 25.7 m over a smooth playa in Western Utah. Data are from highly convective conditions when the magnitude of the Obukhov length (our proxy for the depth of the surface friction layer) was less than 2 m. Our results are somewhat similar to the results reported from the Minnesota experiment of Kaimal et al. (1976), but show significant differences in detail. Our velocity spectra show no evidence of buoyant production of kinetic energy at at the scale of the thermal structures. We interpret our velocity spectra to be the result of outer eddies interacting with the ground, not "local free convection". We observe that velocity spectra represent the spectral distribution of the kinetic energy of the turbulence, so we use energy scales based on total turbulence energy in the convective boundary layer (CBL) to collapse our spectra. For the horizontal velocity spectra this scale is (zi ?o)2/3, where zi is inversion height and ?o is the dissipation rate in the bulk CBL. This scale functionally replaces the Deardorff convective velocity scale. Vertical motions are blocked by the ground, so the outer eddies most effective in creating vertical motions come from the inertial subrange of the outer turbulence. We deduce that the appropriate scale for the peak region of the vertical velocity spectra is (z ?o)2/3 where z is height above ground. Deviations from perfect spectral collapse under these scalings at large and small wavenumbers are explained in terms of the energy transport and the eddy structures of the flow. We find that the peaks of the temperature spectra collapse when wavenumbers are scaled using (z1/2 zi1/2). That is, the lengths of the thermal structures depend on both the lengths of the transporting eddies, ~9z, and the progressive aggregation of the plumes with height into the larger-scale structures of the CBL. This aggregation depends, in top-down fashion, on zi. The whole system is therefore highly organized, with even the smallest structures conforming to the overall requirements of the whole flow

Ground pattern analysis in the Great Plains

There are no author-identified significant results in this report

The Role of Diversity in the Energetics of Plant Communities

Author Institution: Biological Research Laboratories, Syracuse UniversityCommunity organization, which is determined in an environmental matrix that varies in space, time, and resource quality, is an important determinant of fitnesses of constituent populations, [n addition, the fitnesses of individual populations are important determinants of community properties. Changes in species richness and equitability during plant succession indicate that comparative fitnesses of co-occuring populations, as measured by their abilities to contribute to energy flow, become more similar as succession proceeds. The rate of species invasion diminishes with greater diversity, and a smaller proportion of the flora is subject to extinction in a given time period. Community diversity, population fitness, environmental heterogeneity, and population and community stability are members of a complex feedback loop which couples each to the others

Neuroscience and approach/avoidance personality traits: a two stage (valuation-motivation) approach

Many personality theories link specific traits to the sensitivities of the neural systems that control approach and avoidance. But there is no consensus on the nature of these systems. Here we combine recent advances in economics and neuroscience to provide a more solid foundation for a neuroscience of approach/avoidance personality. We propose a two-stage integration of valuation (loss/gain) sensitivities with motivational (approach/avoidance/conflict) sensitivities. Our key conclusions are: (1) that valuation of appetitive and aversive events (e.g. gain and loss as studied by behavioural economists) is an independent perceptual input stage--with the economic phenomenon of loss aversion resulting from greater negative valuation sensitivity compared to positive valuation sensitivity; (2) that valuation of an appetitive stimulus then interacts with a contingency of presentation or omission to generate a motivational 'attractor' or 'repulsor', respectively (vice versa for an aversive stimulus); (3) the resultant behavioural tendencies to approach or avoid have distinct sensitivities to those of the valuation systems; (4) while attractors and repulsors can reinforce new responses they also, more usually, elicit innate or previously conditioned responses and so the perception/valuation-motivation/action complex is best characterised as acting as a 'reinforcer' not a 'reinforcement'; and (5) approach-avoidance conflict must be viewed as activating a third motivation system that is distinct from the basic approach and avoidance systems. We provide examples of methods of assessing each of the constructs within approach-avoidance theories and of linking these constructs to personality measures. We sketch a preliminary five-element reinforcer sensitivity theory (RST-5) as a first step in the integration of existing specific approach-avoidance theories into a coherent neuroscience of personality

Aperiodic String Transducers

Regular string-to-string functions enjoy a nice triple characterization through deterministic two-way transducers (2DFT), streaming string transducers (SST) and MSO definable functions. This result has recently been lifted to FO definable functions, with equivalent representations by means of aperiodic 2DFT and aperiodic 1-bounded SST, extending a well-known result on regular languages. In this paper, we give three direct transformations: i) from 1-bounded SST to 2DFT, ii) from 2DFT to copyless SST, and iii) from k-bounded to 1-bounded SST. We give the complexity of each construction and also prove that they preserve the aperiodicity of transducers. As corollaries, we obtain that FO definable string-to-string functions are equivalent to SST whose transition monoid is finite and aperiodic, and to aperiodic copyless SST