Direct Sensory Input, No Complications & A Token of His Grace

Senior Project submitted to The Division of Arts of Bard College

Foraging under Predation Risk: A test of giving-up densities with samango monkeys in South Africa

Animals frequently make a trade-off between food and safety and will sacrifice feeding effort if it means safety from predators. A forager can also vary its vigilance levels to manage predation risk. Giving-up densities (GUDs), the amount of food items left once a forager has quit an experimental food patch, have been used extensively as measures of foraging behaviour under risk of predation in a wide range of species. Vigilance also serves as an anti-predatory response to predation risk and has been the focus of a range of behavioural studies. However, very few studies have looked at these two measures together. The principal aim of this study was to determine the effect of habitat factors on the foraging behaviour of samango monkeys (Cercopithcus mitis erythrarchus) by measuring GUDs in artificial food patches and foraging behaviour, and relating this to height from the ground, canopy cover, habitat visibility and observed behaviour. The second objective was then to determine the extent to which the experimental approach matched observed behaviour in measuring primate responses to predation risk. The monkeys revealed lower GUDs with increasing height and with decreasing canopy cover and but were not affected by habitat visibility. Vigilance varied considerably with only conspecific and observer vigilance showing significant effects. Conspecific vigilance increased with height and decreasing canopy cover. Vigilance directed at observers increased with decreasing canopy cover. There was no effect of habitat visibility on any of the component behaviours of vigilance. The vigilance behaviour of the monkeys did not completely compliment the GUD results. The findings of this study confirm the prediction that habitat plays a key role in the foraging behaviour of samango monkeys but that vigilance is more sensitive to other factors such as sociality. Further work is required to determine the extent to which experimental approaches based on giving up densities match patterns of antipredatory behaviour recorded by observational methods

Vigilance and control

We sometimes fail unwittingly to do things that we ought to do. And we are, from time to time, culpable for these unwitting omissions. We provide an outline of a theory of responsibility for unwitting omissions. We emphasize two distinctive ideas: (i) many unwitting omissions can be understood as failures of appropriate vigilance, and; (ii) the sort of self-control implicated in these failures of appropriate vigilance is valuable. We argue that the norms that govern vigilance and the value of self-control explain culpability for unwitting omissions

Age differences in perceived workload across a short vigil

The main objective of this research was to investigate age differences in the perceived workload associated with the performance of a demanding, high event rate, vigilance task. Younger participants (n=26) aged 16 to 35 years (M=27.8) and older participants (n=24) aged 45 to 65 years (M=52.2) completed perceived workload scales (NASA-TLX) following a brief practice session (pretest) on the vigilance task, and then again following a test session (posttest) lasting nine minutes. In relation to the vigilance task, a statistically significant performance decrement was identified, but there was no evidence that performance differed according to age in respect to that decrement. However, a dissociation was found in relation to the perceived workload ratings: while no age differences were found in vigilance performance, the workload ratings revealed older participants to perceive a significantly greater increase in workload from pretest to posttest. These findings are considered theoretically in relation to the demands placed upon attentional resources, and their implications for both laboratory-based vigilance research, and workplace systems monitoring situations, are discussed

Comparative Vigilance

A growing body of literature suggests that courts and juries are inclined toward division of liability between two strictly non-negligent or “vigilant” parties. However, standard models of liability rules do not provide for vigilance-based sharing of liability. In this paper, we explore the economic efficiency of liability rules based on comparative vigilance. We devise liability rules that are efficient and that reward vigilance exhibited by the parties. It is commonly believed that discontinuous liability shares are necessary for efficiency, but we develop a liability rule that is both efficient and continuous, based on comparative negligence when both parties are negligent and on comparative vigilance when both parties are vigilant. Moreover, our rule divides accident losses into two parts: one part creates incentives for efficiency; the other part provides equity.Comparative vigilance; equity; economic efficiency; tort liability rules; Nash equilibrium; social costs; pure comparative vigilance; super-symmetric rule

COMPARATIVE VIGILANCE

A growing body of literature suggests that courts and juries are inclined toward division of liability between two strictly non-negligent or “vigilant” parties. However, standard models of liability rules do not provide for vigilance-based sharing of liability. In this paper, we explore the economic efficiency of liability rules based on comparative vigilance. We devise rules that are efficient and that reward vigilance. It is commonly believed that discontinuous liability shares are necessary for efficiency. However we develop a liability rule, which we call the “super-symmetric rule,” that is both efficient and continuous, that is based on comparative negligence when both parties are negligent and on comparative vigilance when both parties are vigilant, and that is always responsive to increased care. Moreover, our super-symmetric rule divides accident losses into two parts: one part creates incentives for efficiency; the other part provides equity.Comparative vigilance, equity, economic efficiency, tort liability rules, Nash equilibrium, social costs, pure comparative vigilance, super-symmetric rule

Automatic vigilance for negative words is categorical and general

With other factors controlled, negative words elicit slower lexical decisions and naming than positive words (Estes & Adelman, 2008; see record 2008-09984-001). Moreover, this marked difference in responding to negative words and to positive words (i.e., between-category discontinuity) was accompanied by relatively uniform responding among negative words (i.e., within-category equivalence), thus suggesting a categorical model of automatic vigilance. Larsen, Mercer, Balota, and Strube (this issue; see record 2008-09984-002) corroborated our observation that valence predicts lexical decision and word naming latencies. However, on the basis of an interaction between linear arousal and linear valence, they claim that automatic vigilance does not occur among arousing stimuli and they purport to reject the categorical model. Here we show that (a) this interaction is logically irrelevant to whether automatic vigilance is categorical; (b) the linear interaction is statistically consistent with the categorical model; (c) the interaction is not observed within the categorical model; and (d) despite having 5 fewer parameters, the categorical model predicts word recognition times as well as the interaction model. Thus, automatic vigilance is categorical and generalizes across levels of arousa

Neuronal avalanches differ from wakefulness to deep sleep - evidence from intracranial depth recordings in humans

Neuronal activity differs between wakefulness and sleep states. In contrast, an attractor state, called self-organized critical (SOC), was proposed to govern brain dynamics because it allows for optimal information coding. But is the human brain SOC for each vigilance state despite the variations in neuronal dynamics? We characterized neuronal avalanches – spatiotemporal waves of enhanced activity - from dense intracranial depth recordings in humans. We showed that avalanche distributions closely follow a power law – the hallmark feature of SOC - for each vigilance state. However, avalanches clearly differ with vigilance states: slow wave sleep (SWS) shows large avalanches, wakefulness intermediate, and rapid eye movement (REM) sleep small ones. Our SOC model, together with the data, suggested first that the differences are mediated by global but tiny changes in synaptic strength, and second, that the changes with vigilance states reflect small deviations from criticality to the subcritical regime, implying that the human brain does not operate at criticality proper but close to SOC. Independent of criticality, the analysis confirms that SWS shows increased correlations between cortical areas, and reveals that REM sleep shows more fragmented cortical dynamics

Small states and the pillars of economic resilience

This chapter reviews the role of the Commonwealth Secretariat in promoting the interests of small states. Thirty-two of the Commonwealth's 53 member countries are small states, mostly with populations of less than 1.5 million. The Secretariat attaches high priority to supporting their integration in the global economy, building their economic resilience and competitiveness. The Secretariat provides advocacy, policy advice and technical assistance to small states, with a focus on the transition to the changing global trade regime, in an attempt to strengthen their capacity to exploit new opportunities arising from globalisation.peer-reviewe

Business and Human Rights as a Galaxy of Norms

In the last several years, there has been an increasing tendency to view the impacts of transnational business operations through the lens of human rights law. A major obstacle to holding companies accountable for the harms that they impose, however, has been the separate legal identity of corporate subsidiaries and of contractors in a company\u27s supply chain. France\u27s recently enacted duty of vigilance statute seeks to overcome this obstacle by imposing a duty on companies to identify potential serious human rights violations by their subsidiaries and by companies with which they have an “established commercial relationship.” Failure to engage in such vigilance can subject a company to liability for damages resulting from such failure. This Article situates the new French duty of vigilance within a broader set of norms that can be characterized as the Business and Human Rights Galaxy. This Galaxy consists of five rings that represent standards and expectations ranging from classic enforceable “hard law” to voluntary principles generated by private parties, multi-stakeholder initiatives, and international organizations. The provisions in these rings are related in fluid and dynamic ways and exert varying degrees of gravitational influence on one another. Thus, for instance, what are conventionally regarded as forms of hard law may draw on voluntary private standards in setting expectations for behavior, and soft law norms may be incorporated into legally enforceable contract provisions between companies and their suppliers. This Article suggests that appreciation of these dynamics can furnish guidance in interpreting the novel duty of vigilance that the new French statute establishes. In particular, the common law duty of care and the United Nations Guiding Principles on Business and Human Rights can illuminate the nature and scope of the duty of vigilance. At the same time, the introduction of the new French statute into the Business and Human Rights Galaxy means that it too has the potential to influence provisions in other rings of the Galaxy