The face-sensitivity of the n170 component

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Attention modulates the processing of emotional expression triggered by foveal faces

To investigate whether the processing of emotional expression for faces presented within foveal vision is modulated by spatial attention, event-related potentials (ERPs) were recorded in response to stimulus arrays containing one fearful or neutral face at fixation, which was flanked by a pair of peripheral bilateral lines. When attention was focused on the central face, an enhanced positivity was elicited by fearful as compared to neutral faces. This effect started at 160 ms post-stimulus, and remained present for the remainder of the 700 ms analysis interval. When attention was directed away from the face towards the line pair, the initial phase of this emotional positivity remained present, but emotional expression effects beyond 220 ms post-stimulus were completely eliminated. These results demonstrate that when faces are presented foveally, the initial rapid stage of emotional expression processing is unaffected by attention. In contrast, attentional task instructions are effective in inhibiting later, more controlled stages of expression analysis

Shifts of attention in the early blind: an ERP study of attentional control processes in the absence of visual spatial information

To investigate the role of visual spatial information in the control of spatial attention, event-related brain potentials (ERPs) were recorded during a tactile attention task for a group of totally blind participants who were either congenitally blind or had lost vision during infancy, and for an age-matched, sighted control group who performed the task in the dark. Participants had to shift attention to the left or right hand (as indicated by an auditory cue presented at the start of each trial) in order to detect infrequent tactile targets delivered to this hand. Effects of tactile attention on the processing of tactile events, as reflected by attentional modulations of somatosensory ERPs to tactile stimuli, were very similar for early blind and sighted participants, suggesting that the capacity to selectively process tactile information from one hand versus the other does not differ systematically between the blind and the sighted. ERPs measured during the cue–target interval revealed an anterior directing attention negativity (ADAN) that was present for the early blind group as well as for the sighted control group. In contrast, the subsequent posterior late direction attention negativity (LDAP) was absent in both groups. These results suggest that these two components reflect functionally distinct attentional control mechanisms which differ in their dependence on the availability of visually coded representations of external space

Why the item will remain the unit of attentional selection in visual search

Hulleman & Olivers reject item-based serial models of visual search, and suggest that items are processed equally and globally during each fixation period. However, neuroscientific studies have shown that attentional biases can emerge in parallel but in a spatially selective item-based fashion. Even within a parallel architecture for visual search, the item remains the critical unit of selection

ERP correlates of tactile spatial attention differ under intra- and intermodal conditions

To investigate whether the mechanisms underlying endogenous tactile spatial attention differ under pure tactile compared to mixed modality conditions event-related brain potentials (ERPs) were recorded to bilateral tactile and visual cues and tactile imperative stimuli. In the cue-stimulus interval the anterior directing attention negativity (ADAN) was present contralateral to the side of the attentional shift. Importantly, under pure tactile conditions this component persisted until imperative stimulus onset, while it diminished under intermodal conditions. Furthermore, post-tactile stimulus onset attentional modulations were present for the P100 component and later latencies under intermodal conditions. In contrast, under pure tactile conditions attentional modulations only emerged for the N140 component and later latencies. It is suggested that mechanisms underlying attentional orienting and selection are not entirely supramodal but depend in part on the modalities involved

A Multi-Level Process of Adaption and Resistance

During the course of bio-prospecting and biodiversity conservation projects, scientists, researchers from the life-science industry, and environmental protection groups attempt to access indigenous and traditional communities’ knowledge of the local biodiversity. They confront these groups with the idea that their knowledge can be commercialized. Although the affected communities partly adapt to this view, they insist on their right to decide autonomously and by their own laws whether they are willing to share their knowledge. External actors, however, often reject the right of indigenous self- determination. The evolving conflicts do not only take place on a local level – varying domestic regulatory approaches also shape them. At the same time, a multitude of international organizations also address the issue of access to traditional knowledge, and their activities in turn shape interactions on a domestic and local level. In this paper, the complex interactions that are associated with the access to traditional knowledge shall be regarded as a multi-level process of adaptation and resistance. Empirically, this paper focuses on traditional knowledge policies in India and Brazil. The analysis of the interplay between local, national, and international traditional knowledge regulations in both countries shall serve to explore some possible avenues for further research on processes of adaption and resistance.Im Rahmen von Bioprospektionen und Projekten zum Erhalt der Biodiversität versuchen Wissenschaftler, Forscher aus Unternehmen des Life Sciences Bereichs und Umweltschutzgruppen, Zugang zum Wissen indigener und traditioneller Bevölkerungsgruppen über die natürliche Artenvielfalt zu erhalten. Sie konfrontieren diese Gruppen dabei mit der Vorstellung, dass ihr Wissen einer kommerziellen Verwertung zugeführt werden kann. Obwohl die hiervon betroffenen Gruppen sich dieser Sichtweise nicht vollends verschließen, bestehen sie darauf, selbst und entsprechend ihres Gewohnheitsrechts darüber zu entscheiden, ob sie ihr Wissen offenbaren und verbreiten wollen. Externe Akteure verweigern ihnen jedoch häufig das Recht der Selbstbestimmung. Obwohl die hieraus resultierenden Konflikte sich zumeist auf der lokalen Ebene abspielen, wird ihr Ausgang wesentlich von nationalstaatlichen Regulierungen bestimmt. Gleichzeitig wird das Thema in zahlreichen internationalen Organisationen bearbeitet, deren Initiativen die Interaktionen auf nationalstaatlicher und lokaler Ebene prägen. In diesem Arbeitspapier werden die konfliktiven Beziehungszusammenhänge, die beim Zugang zu traditionalem Wissen entstehen, als ein Prozess von Aneignung und Abwehr aufgefasst, der in ein Mehrebenensystem eingebunden ist. Empirisch konzentriert sich die Analyse auf die Situation in Indien und Brasilien. Die Untersuchung des Zusammenspiels von lokalen, nationalstaatlichen und internationalen Regulierungen soll dazu dienen, mögliche Forschungszugänge zu Aneignungs- und Abwehrprozessen aufzuzeigen

Large phase-transition-induced magnetic anisotropy change in (Co/Pt)2/VO2 heterostructure

We report the phase-transition controlled magnetic anisotropy modulation in the (Co/Pt)2/VO2 heterostructure, where VO2 is introduced into the system to applied an interfacial strain by its metal-insulator transition. A large reversible modulation of the perpendicular magnetic anisotropy (PMA) reaching 38 kJ/m3 is observed during this process. The calculated energy density variation of interfacial anisotropy reaches 100 mJ/m2, which shows significant advantage over traditional modulation strategies. Further experimental results including magnetization change versus temperature, strain buffered modulation and pre-strained sample comparison prove that the interfacial coupling between VO2 and PMA layers plays a crucial role in this modulation. This work, demonstrating the great potential of phase-transition material in efficient magnetic anisotropy modulation, would benefit the exploration for low-power consumption devices

The role of spatial frequency information for ERP components sensitive to faces and emotional facial expression

To investigate the impact of spatial frequency on emotional facial expression analysis, ERPs were recorded in response to low spatial frequency (LSF), high spatial frequency (HSF), and unfiltered broad spatial frequency (BSF) faces with fearful or neutral expressions, houses, and chairs. In line with previous findings, BSF fearful facial expressions elicited a greater frontal positivity than BSF neutral facial expressions, starting at about 150 ms after stimulus onset. In contrast, this emotional expression effect was absent for HSF and LSF faces. Given that some brain regions involved in emotion processing, such as amygdala and connected structures, are selectively tuned to LSF visual inputs, these data suggest that ERP effects of emotional facial expression do not directly reflect activity in these regions. It is argued that higher order neocortical brain systems are involved in the generation of emotion-specific waveform modulations. The face-sensitive N170 component was neither affected by emotional facial expression nor by spatial frequency information