Column ratio mapping: a processing technique for atomic resolution high angle annular dark field(HAADF) images

An image processing technique is presented for atomic resolution high-angle annular dark-field (HAADF) images that have been acquired using scanning transmission electron microscopy (STEM). This technique is termed column ratio mapping and involves the automated process of measuring atomic column intensity ratios in high-resolution HAADF images. This technique was developed to provide a fuller analysis of HAADF images than the usual method of drawing single intensity line profiles across a few areas of interest. For instance, column ratio mapping reveals the compositional distribution across the whole HAADF image and allows a statistical analysis and an estimation of errors. This has proven to be a very valuable technique as it can provide a more detailed assessment of the sharpness of interfacial structures from HAADF images. The technique of column ratio mapping is described in terms of a [1 1 0]-oriented zinc-blende structured AlAs/GaAs superlattice using the 1 Å-scale resolution capability of the aberration-corrected SuperSTEM 1 instrument

Beliefs about the Minds of Others Influence How We Process Sensory Information

Attending where others gaze is one of the most fundamental mechanisms of social cognition. The present study is the first to examine the impact of the attribution of mind to others on gaze-guided attentional orienting and its ERP correlates. Using a paradigm in which attention was guided to a location by the gaze of a centrally presented face, we manipulated participants' beliefs about the gazer: gaze behavior was believed to result either from operations of a mind or from a machine. In Experiment 1, beliefs were manipulated by cue identity (human or robot), while in Experiment 2, cue identity (robot) remained identical across conditions and beliefs were manipulated solely via instruction, which was irrelevant to the task. ERP results and behavior showed that participants' attention was guided by gaze only when gaze was believed to be controlled by a human. Specifically, the P1 was more enhanced for validly, relative to invalidly, cued targets only when participants believed the gaze behavior was the result of a mind, rather than of a machine. This shows that sensory gain control can be influenced by higher-order (task-irrelevant) beliefs about the observed scene. We propose a new interdisciplinary model of social attention, which integrates ideas from cognitive and social neuroscience, as well as philosophy in order to provide a framework for understanding a crucial aspect of how humans' beliefs about the observed scene influence sensory processing

Nicotine enhances an auditory Event-Related Potential component which is inversely related to habituation

Nicotine is a psychoactive substance that is commonly consumed in the context of music. However, the reason why music and nicotine are coconsumed is uncertain. One possibility is that nicotine affects cognitive processes relevant to aspects of music appreciation in a beneficial way. Here we investigated this possibility using Event-Related Potentials (ERPs). Participants underwent a simple decision-making task (to maintain attentional focus), responses to which were signaled by auditory stimuli. Unlike most previous research looking at the effects of nicotine on auditory processing, we used tones of different pitch, a fundamental element of music. In addition, unlike most other studies, we tested non-smoking subjects to avoid withdrawal-related complications. We found that nicotine (4.0 mg, administered as gum) increased P2 amplitude in the frontal region. Since a decrease in P2 amplitude and latency is related to habituation processes, and an enhanced ability to disengage from irrelevant stimuli, our findings suggest that nicotine may cause a reduction in habituation, resulting in non-smokers being less able to adapt to repeated stimuli. A corollary of that decrease in adaptation may be that nicotine extends the temporal window during which a listener is able and willing to engage with a piece of music

‘As a woman…’; ‘As a Muslim…’: Subjects, positions and counter-terrorism powers in the United Kingdom

This article presents findings from original focus group research on the importance of identity claims within public understandings of counter-terrorism across the UK. Following a review of existing literature on the terrorism/counter-terrorism/identity nexus, the article introduces four prominent subject positions inhabited within public articulations of counter-terrorism powers: the ‘Muslim’, the ‘target’, the ‘woman’ and the ‘unaffected’. Positions such as these, we argue, both enable and inhibit particular normative, political and anecdotal claims about counter-terrorism frameworks and their impact upon the body politic. This, we suggest, is demonstrative of the co-constitutive role between counter-terrorism and identity claims. Thus, on the one hand, counter-terrorism initiatives work to position individuals socially, politically, and culturally: (re)producing various religious, ethnic and other identities. Yet, at the same time, specific subject positions are integral to the articulation of people’s attitudes toward developments in counter-terrorism. The article concludes by thinking through some of the implications of this, including for resistance toward securitising moves and for citizenship more generally

Exploring the cultural dimensions of environmental victimization

It has become increasingly clear in recent years that our understanding of ‘victimisation’ is informed by a whole range of societal and political factors which extend well beyond whatever particular form of words appears in any given directive, code or legislative instrument concerning crime, crime victims or criminal justice systems. In this paper, I will seek for the first time to apply recent developments in our understanding of so-called 'cultural victimology' to the issue of environmental harm and its impact on human and non-human animals. McCGarry and Waklate (2015) characterise cultural victimology as broadly comprising of two key aspects. These are the wider sharing and reflection of individual and collective victimisation experiences on the one hand and, on the other, the mapping of those experiences through the criminal justice process. In this discussion I will examine how environmental victimisation is viewed by and presented to society at large and will argue that such representations often fail, as a form of testimony, to adequately convey the traumas involved. Nor is this achieved through the application of present models of criminal, civil or administrative justice regimes in many jurisdictions. This lack of cultural acknowledgement of the harms vested on environmental victims, it is argued, afford us a clearer understand of the continued reticence amongst lawmakers, politicians and legal practitioners to adequately address the impacts of such victimisation through effective justice or regulatory mechanisms. This is unfortunate given that the often collective nature of environmental victimisation makes this particularly suited to a more cultural analysis and understanding. It is argued that various forms of environmental mediation processes might hold the key to this cultural reticence to accept environmental harm as a 'real' and pressing problem as compared to other criminal and civil justice concerns

Decision making, the P3, and the locus coeruleus-norepinephrine system.

Psychologists and neuroscientists have had a long-standing interest in the P3, a prominent component of the event-related brain potential. This review aims to integrate knowledge regarding the neural basis of the P3 and to elucidate its functional role in information processing. The authors review evidence suggesting that the P3 reflects phasic activity of the neuromodulatory locus coeruleus-norepinephrine (LC-NE) system. They discuss the P3 literature in the light of empirical findings and a recent theory regarding the information-processing function of the LC-NE phasic response. The theoretical framework emerging from this research synthesis suggests that the P3 reflects the response of the LC-NE system to the outcome of internal decision-making processes and the consequent effects of noradrenergic potentiation of information processing. Copyright 2005 by the American Psychological Association

Sensory ERP effects in auditory distraction: did we miss the main event?

Event-related potentials (ERPs) offer unique insights into processes related to involuntary attention changes triggered by rare, unpredictably occurring sensory events, that is, distraction. Contrasting ERPs elicited by distracters and frequent standard stimuli in oddball paradigms allowed the formulation of a three-stage model describing distraction-related processing: first, the distracting event is highlighted by a sensory filter. Second, attention is oriented towards the event, and finally, the task-optimal attention set is restored, or task priorities are changed. Although this model summarizes how distracting stimulus information is processed, not much is known about the cost of taking this exceptional route of processing. The present study demonstrates the impact of distraction on sensory processing. Participants performed a Go/NoGo tone-duration discrimination task, with infrequent pitch distracters. In the two parts of the experiment the duration-response mapping was reversed. Contrasts of distracter and standard ERPs revealed higher P3a- and reorienting negativity amplitudes for short than for long tones, independently from response type. To understand the cause of these asymmetries, short vs. long ERP contrasts were calculated. The ERP pattern showed that short standards elicited an attention-dependent offset response, which was abolished for short distracters. That is, the apparent P3a- and RON enhancements were caused by the removal of a task-related attentional sensory enhancement. This shows that the disruption of task-optimal attention set precedes the elicitation of the P3a, which suggests that P3a does not reflect a process driving the initial distraction-related attention change

Informers, Agents and the Liberal Ideology of Collusion in Northern Ireland

There is now considerable evidence of systemic and institutionalised collusion between state forces and loyalists paramilitary groups during the Northern Ireland conflict, not least in the late 1980s and early 1990s. Focusing on a critical reading of the 2012 de Silva report into the killing of human rights lawyer, Pat Finucane, this article examines state collusive practices surrounding the handling of agents and informers as evidence of a culture of collusion extending into the highest echelons of state institutions. The article will argue that such practices evidence an approach to state counterinsurgency predicated on a “doctrine of necessity” and what can be understood as a “liberal ideology of collusion”

Transient activation of dopaminergic neurons during development modulates visual responsiveness, locomotion and brain activity in a dopamine ontogeny model of schizophrenia

It has been observed that certain developmental environmental risk factors for schizophrenia when modeled in rodents alter the trajectory of dopaminergic development, leading to persistent behavioural changes in adults. This has recently been articulated as the "dopamine ontogeny hypothesis of schizophrenia". To test one aspect of this hypothesis, namely that transient dopaminergic effects during development modulate attention-like behavior and arousal in adults, we turned to a small-brain model, Drosophila melanogaster. By applying genetic tools allowing transient activation or silencing of dopaminergic neurons in the fly brain, we investigated whether a critical window exists during development when altered dopamine (DA) activity levels could lead to impairments in arousal states in adult animals. We found that increased activity in dopaminergic neurons in later stages of development significantly increased visual responsiveness and locomotion, especially in adult males. This misallocation of visual salience and hyperactivity mimicked the effect of acute methamphetamine feeding to adult flies, suggesting up-regulated DA signaling could result from developmental manipulations. Finally, brain recordings revealed significantly reduced gamma-band activity in adult animals exposed to the transient developmental insult. Together, these data support the idea that transient alterations in DA signaling during development can permanently alter behavior in adults, and that a reductionist model such as Drosophila can be used to investigate potential mechanisms underlying complex cognitive disorders such as schizophrenia