53 resultados para Gaze
Resumo:
Early visual cortex (EVC) participates in visual feature memory and the updating of remembered locations across saccades, but its role in the trans-saccadic integration of object features is unknown. We hypothesized that if EVC is involved in updating object features relative to gaze, feature memory should be disrupted when saccades remap an object representation into a simultaneously perturbed EVC site. To test this, we applied transcranial magnetic stimulation (TMS) over functional magnetic resonance imaging-localized EVC clusters corresponding to the bottom left/right visual quadrants (VQs). During experiments, these VQs were probed psychophysically by briefly presenting a central object (Gabor patch) while subjects fixated gaze to the right or left (and above). After a short memory interval, participants were required to detect the relative change in orientation of a re-presented test object at the same spatial location. Participants either sustained fixation during the memory interval (fixation task) or made a horizontal saccade that either maintained or reversed the VQ of the object (saccade task). Three TMS pulses (coinciding with the pre-, peri-, and postsaccade intervals) were applied to the left or right EVC. This had no effect when (a) fixation was maintained, (b) saccades kept the object in the same VQ, or (c) the EVC quadrant corresponding to the first object was stimulated. However, as predicted, TMS reduced performance when saccades (especially larger saccades) crossed the remembered object location and brought it into the VQ corresponding to the TMS site. This suppression effect was statistically significant for leftward saccades and followed a weaker trend for rightward saccades. These causal results are consistent with the idea that EVC is involved in the gaze-centered updating of object features for trans-saccadic memory and perception.
Resumo:
Recent evidence indicates that dogs' sociocognitive abilities and behaviour in a test situation are shaped by both genetic factors and life experiences. We used the 'unsolvable task' paradigm to investigate the effect of breed and age/experience on the use of human-directed gazing behaviour. Following a genetic classification based on recent genome analyses, dogs were allocated to three breed groups, namely Primitive, Hunting/Herding and Molossoid. Furthermore, we tested dogs at 2 months, 4.5. months and as adults. The test consisted of three solvable trials in which dogs could obtain food by manipulating a plastic container followed by an unsolvable trial in which obtaining the food became impossible. The dogs' behaviour towards the apparatus and the people present was analysed. At 2 months no breed group differences emerged and although human-directed gazing behaviour was observed in approximately half of the pups, it occurred for brief periods, suggesting that the aptitude to use human-directed gazing as a request for obtaining help probably develops at a later date when dogs have had more experience with human communication. Breed group differences, however, did emerge strongly in adult dogs and, although less pronounced, also in 4.5-month-old subjects, with dogs in the Hunting/Herding group showing significantly more human-directed gazing behaviour than dogs in the other two breed groups. These results suggest that, although the domestication process may have shaped the dog's human-directed communicative abilities, the later selection for specific types of work might also have had a significant impact on their emergence. © 2011 The Association for the Study of Animal Behaviour.
Resumo:
Both genetic factors and life experiences appear to be important in shaping dogs' responses in a test situation. One potentially highly relevant life experience may be the dog's training history, however few studies have investigated this aspect so far. This paper briefly reviews studies focusing on the effects of training on dogs' performance in cognitive tasks, and presents new, preliminary evidence on trained and untrained pet dogs' performance in an 'unsolvable task'. Thirty-nine adult dogs: 13 trained for search and rescue activities (S&R group), 13 for agility competition (Agility group) and 13 untrained pets (Pet group) were tested. Three 'solvable' trials in which dogs could obtain the food by manipulating a plastic container were followed by an 'unsolvable' trial in which obtaining the food became impossible. The dogs' behaviours towards the apparatus and the people present (owner and researcher) were analysed. Both in the first 'solvable' and in the 'unsolvable' trial the groups were comparable on actions towards the apparatus, however differences emerged in their human-directed gazing behaviour. In fact, results in the 'solvable' trial, showed fewer S&R dogs looking back at a person compared to agility dogs, and the latter alternating their gaze between person and apparatus more frequently than pet dogs. In the unsolvable trial no difference between groups emerged in the latency to look at the person however agility dogs looked longer at the owner than both pet and S&R dogs; whereas S&R dogs exhibited significantly more barking (always occurring concurrently to looking at the person or the apparatus) than both other groups. Furthermore, S&R dogs alternated their gaze between person and apparatus more than untrained pet dogs, with agility dogs falling in between these two groups. Thus overall, it seems that the dogs' human-directed communicative behaviours are significantly influenced by their individual training experiences. © 2009 Elsevier B.V. All rights reserved.
Resumo:
Among Brethren fisher families in Gamrie, northeast Scotland, professional clergy and written liturgy are held to be blasphemous denials of the true workings of the Holy Spirit. God, I was told, chooses to speak through all born-again (male) persons, unrestricted by the vain repetitions of lettered clerics and their prayer books. In this context, confession of one’s own sin is a private and pointedly interior affair. In Gamrie, not only did every man seek to be his own skipper, but also his own priest. Yet, much of Brethren worship is given over to ritualised acts of confession. So whose sins do the Brethren confess, and to what end? This article argues that among the Brethren of Gamrie, such acts involve confessing not one’s own sin, but the sins of a ‘sick’ and ‘fallen’ world. More than this, by attending to the sociological (as opposed to theological) processes of confessing the sins of another, we see a collapse in the distinction between confiteor and credo that has so dogged anthropological studies of Christianity. In Brethren prayer and bible study, as well as in everyday gossip, the “I confess” of the confiteor and the “I believe” of credo co-constitute one another in and through evidences of the ‘lostness’ of ‘this present age’. But how, if at all, does this solve ‘the problem of sin’? This article suggests that, with the ritual gaze of confession turned radically outward, Brethren announcements of global wickedness enact (in a deliberate tautology) both a totalising call for repentance from sin, and a millenarian creed of the imminent apocalypse. Here, the problem of ritual can be understood as the problem of (partially failed) expiation.
Resumo:
Much of the recent literature on youth justice has focused on administrative aspects of the system and the socio-political contexts that have led to the ‘production’ of the youthful offender as a subject and locus of intervention. This has largely been driven by the extent to which youth justice has been crafted as a distinct penal sphere, evident in its unyoking from universal children’s services (Muncie and Goldson, 2013) and the establishment of separate agencies to administer and govern this ‘system’ (Souhami, 2014). Driven by policy hyperactivity and a plethora of legislation expanding the reach of the system, for much of the 1990s and 2000s increasing numbers of young people were brought under its gaze.
Particular attention has been paid to the impact of neo-liberal governance on the discourses, rationales and philosophies underpinning contemporary youth justice policy and practice. Writing specifically in the English and Welsh context, several authors have identified that the resulting ‘system’ embodies multiple, contradictory and competing discourses (Muncie, 2006; Fergusson, 2007; Gray, 2013). Within this ‘melting pot’ Fergusson (2007) notes the disjuncture between policy rhetoric, implementation and lived experience and Phoenix (2015) argues that systems-based analyses, much in favour amongst academics, foreclose a wider consideration of questions of what ‘justice’ actually means.
Recent attention towards the perspectives of practitioners working in this sphere has pointed to greater nuances than broader penal narratives suggest (see: Field, 2007; Briggs, 2013; Gray, 2013; Kelly and Armitage, 2015). Yet similar attention has not been given to experiences of youth justice (for an exception see – Phoenix and Kelly, 2013). However, it is precisely young people’s experiences, which would add significantly to current knowledge and potentially bridge the gap between discussions about penal philosophies, how youth justice policies are framed, how they are enacted and how they are experienced.
This chapter provides an overview of recent developments in the field of youth justice and penality in the United Kingdom. The chapter argues that a theoretical focus on macro-level trends (Hannah-Moffat and Lynch, 2012), alongside a narrowly defined research agenda, have largely excluded young people’s experiences of justice and punishment from contemporary analysis. Drawing on young people experiences of different aspects of youth justice in Northern Ireland and beyond, the chapter illuminates what a close understanding of lived experience can add to knowledge. In particular it demonstrates that the effects of interventions can be different to their aims and intentions; and that re-instating the youth experience can add support to calls for greater attention to wider issues of social justice.
Resumo:
Infection with Schistosoma japonicum causes high levels of pathology that is predominantly determined by the cellular and humoral response of the host. However, the specific antibody response that arises during the development of disease is largely undescribed in Asian schistosomiasis-endemic populations. A schistosome protein microarray was used to compare the antibody profiles of subjects with acute infection, with early or advanced disease associated with severe pathology, with chronic infection, and subjects exposed but stool negative for S. japonicum eggs to the antibody profiles of nonexposed controls. Twenty-five immunodominant antigens were identified, including vaccine candidates, tetraspanin-related proteins, transporter molecules, and unannotated proteins. Additionally, individuals with severe pathology had a limited specific antibody response, suggesting that individuals with mild disease may use a broad and strong antibody response, particularly against surface-exposed proteins, to control pathology and/or infection. Our study has identified specific antigens that can discriminate between S. japonicum-exposed groups with different pathologies and may also allow the host to control disease pathology and provide resistance to parasite infection.
Resumo:
The schistosome blood flukes are some of the largest global causes of parasitic morbidity. Further study of the specific antibody response during schistosomiasis may yield the vaccines and diagnostics needed to combat this disease. Therefore, for the purposes of antigen discovery, sera and antibody-secreting cell (ASC) probes from semi-permissive rats and sera from susceptible mice were used to screen a schistosome protein microarray. Following Schistosoma japonicum infection, rats had reduced pathology, increased antibody responses and broader antigen recognition profiles compared with mice. With successive infections, rat global serological reactivity and the number of recognized antigens increased. The local antibody response in rat skin and lung, measured with ASC probes, increased after parasite migration and contributed antigen-specific antibodies to the multivalent serological response. In addition, the temporal variation of anti-parasite serum antibodies after infection and reinfection followed patterns that appear related to the antigen driving the response. Among the 29 antigens differentially recognized by the infected hosts were numerous known vaccine candidates, drug targets and several S. japonicum homologs of human schistosomiasis resistance markers-the tegument allergen-like proteins. From this set, we prioritized eight proteins that may prove to be novel schistosome vaccine and diagnostic antigens.