1,582 research outputs found
A sala: Exposições 2014: Projeto de Extensão Ações Educativas na Galeria de Arte A Sala do Centro de Artes da UFPel
A SALA é de suma importância, enquanto instância educacional e expositiva pública, localizada no Centro de Artes, que promove a partilha da produção artística contemporânea com o corpo docente, o corpo discente e com a comunidade em geral. É o espaço que apresenta a obra de arte e promove a
sua fruição, como também envolve práticas profissionais que possibilitam aos estudantes
de arte conhecer as etapas que envolvem a realização de uma exposição, ou seja, os projetos de curadoria, de expografia, a montagem, a produção gráfica de divulgação, encontros com o artista, ações educativas, a documentação, entre outras atividades necessárias para que as mostras
aconteçam. De maneira intensa e constante os alunos são colaboradores e apreciadores das exposições, adquirindo saberes indispensáveis à formação universitária
Progression of extrapyramidal signs in Alzheimer's disease. clinical and neuropathological correlates
Extrapyramidal signs (EPS) are frequent in Alzheimer's disease (AD) and core manifestation of related diseases, i.e., dementia with Lewy bodies and Parkinson's disease; furthermore, Lewy bodies and AD-type pathology occur in all three conditions
Task conflict in the Stroop task: When Stroop interference decreases as Stroop facilitation increases in a low task conflict context.
In the present study participants completed two blocks of the Stroop task, one in which the response-stimulus interval (RSI) was 3500 ms and one in which RSI was 200 ms. It was expected that, in line with previous research, the shorter RSI would induce a low Task Conflict context by increasing focus on the color identification goal in the Stroop task and lead to a novel finding of an increase in facilitation and simultaneous decrease in interference. Such a finding would be problematic for models of Stroop effects that predict these indices of performance should be affected in tandem. A crossover interaction is reported supporting these predictions. As predicted, the shorter RSI resulted in incongruent and congruent trial reaction times (RTs) decreasing relative to a static neutral baseline condition; hence interference decreased as facilitation increased. An explanatory model (expanding on the work of Goldfarb and Henik, 2007) is presented that: (1) Shows how under certain conditions the predictions from single mechanism models hold true (i.e., when Task conflict is held constant); (2) Shows how it is possible that interference can be affected by an experimental manipulation that leaves facilitation apparently untouched; and (3) Predicts that facilitation cannot be independently affected by an experimental manipulation
The coupling between spatial attention and other components of task-set: a task switching investigation
Is spatial attention reconfigured independently of, or in tandem with, other task-set components when the task changes? We tracked the eyes of participants cued to perform one of three digit-classification tasks, each consistently associated with a distinct location. Previously we observed, on task switch trials, a substantial delay in orientation to the task-relevant location and tendency to fixate the location of the previously relevant task – “attentional inertia”. In the present experiments the cues specified (and instructions emphasised) the relevant location rather than the current task. In Experiment 1, with explicit spatial cues (arrows or spatial adverbs), the previously documented attentional handicaps all but disappeared, whilst the performance “switch cost” increased. Hence, attention can become decoupled from other aspects of task-set, but at a cost to the efficacy of task-set preparation. Experiment 2 used arbitrary single-letter cues with instructions and a training regime that encouraged participants to interpret the cue as indicating the relevant location rather than task. As in our previous experiments, and unlike in Experiment 1, we now observed clear switch-induced attentional delay and inertia, suggesting that the natural tendency is for spatial attention and task-set to be coupled and that only quasi-exogenous location cues decouple their reconfiguration
A change of task prolongs early processes: evidence from ERPs in lexical tasks.
PublishedJournal ArticleSwitching tasks costs time. Allowing time to prepare reduces the cost, but usually leaves an irreducible "residual cost." Most accounts of this residual cost locate it within the response-selection stage of processing. To determine which processing stage is affected, we measured event-related potentials (ERPs) as participants performed a reading task or a perceptual judgment task, and examined the effect of a task switch on early markers of lexical processing. A task cue preceding a string of blue and red letters instructed the participant either to read the letter string (for a semantic classification in Experiment 1, and a lexical decision in Experiment 2) or to judge the symmetry of its color pattern. In Experiment 1, having to switch to the reading task delayed the evolution of the effect of word frequency on the reading task ERP by a substantial fraction of the effect on reaction time (RT). In Experiment 2, a task switch delayed the onset of the effect of lexical status on the ERP by about the same extent that it prolonged the RT. These effects indicate an early locus of (most of) the residual switch cost: We propose that this reflects a form of task-related attentional inertia. Other findings have implications for the automaticity of lexical access: Effects of frequency, lexicality, and orthographic familiarity on ERPs in the symmetry task indicated involuntary, but attenuated, orthographic and lexical processing even when attention was focused on a nonlexical property.Economic and Social Research Counci
Sensorineural Hearing Loss and the Diagnosis of Acoustic Neuroma
Sensorineural hearing loss and tinnitus are gradually receiving more attention in medicine due to advances in diagnosis and treatment. Acoustic neuromas can now be detected when they are small, and early microsurgical removal results in the lowest overall morbidity. We examine the historical development of acoustic neuroma management, discuss current diagnosis and treatment, and present illustrative cases from our recent experience. Complaints of tinnitus and hearing loss, especially when unilateral, require appropriate medical evaluation
More attention to attention? An eye-tracking investigation of selection of perceptual attributes during a task switch
This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.Switching tasks prolongs response times, an effect reduced but not eliminated by active preparation. To explore the role of attentional selection of the relevant stimulus attribute in these task-switch costs, we measured eye fixations in participants cued to identify either a face or a letter displayed on its forehead. With only 200 ms between cue and stimulus onsets, the eyes fixated the currently relevant region of the stimulus less and the irrelevant region more on switch than on repeat trials, at stimulus onset and for 500 ms thereafter, in a pattern suggestive of delayed orientation of attention to the relevant region on switch trials. With 800 ms to prepare, both switch costs and inappropriate fixations were reduced, but on switch trials participants still tended (relative to repeat trials) to fixate the now-irrelevant region more at stimulus onset and to maintain fixation on, or refixate, the irrelevant region more during the next 500 ms. The size of this attentional persistence was associated with differences in performance costs between and within participants. We suggest that reorientation of attention is an important, albeit somewhat neglected and controversial, component of advance task-set reconfiguration and that the task-set inertia (or reactivation) to which many attribute the residual task-switch cost seen after preparation includes inertia in (or reactivation of) attentional parameters
Is performance in task-cuing experiments mediated by task set selection or associative compound retrieval?
Journal ArticleThis article may not exactly replicate the final version published in the APA journal. It is not the copy of record. The definitive version was published as: Forrest, C.L.D., Monsell, S., and McLaren I.P.L. (2014). Is performance in task-cuing experiments mediated by task-set selection or associative compound retrieval? Journal of Experimental Psychology: Learning, Memory and Cognition, 40, 1002-1024. http://dx.doi.org/10.1037/a0035981© 2014 American Psychological AssociationTask-cuing experiments are usually intended to explore control of task set. But when small stimulus sets are used, they plausibly afford learning of the response associated with a combination of cue and stimulus, without reference to tasks. In 3 experiments we presented the typical trials of a task-cuing experiment: a cue (colored shape) followed, after a short or long interval, by a digit to which 1 of 2 responses was required. In a tasks condition, participants were (as usual) directed to interpret the cue as an instruction to perform either an odd/even or a high/low classification task. In a cue + stimulus → response (CSR) condition, to induce learning of mappings between cue-stimulus compound and response, participants were, in Experiment 1, given standard task instructions and additionally encouraged to learn the CSR mappings; in Experiment 2, informed of all the CSR mappings and asked to learn them, without standard task instructions; in Experiment 3, required to learn the mappings by trial and error. The effects of a task switch, response congruence, preparation, and transfer to a new set of stimuli differed substantially between the conditions in ways indicative of classification according to task rules in the tasks condition, and retrieval of responses specific to stimulus-cue combinations in the CSR conditions. Qualitative features of the latter could be captured by an associative learning network. Hence associatively based compound retrieval can serve as the basis for performance with a small stimulus set. But when organization by tasks is apparent, control via task set selection is the natural and efficient strategy
Self-paced preparation for a task switch eliminates attentional inertia but not the performance switch cost
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.The performance overhead associated with changing tasks (the "switch cost") usually diminishes when the task is specified in advance but is rarely eliminated by preparation. A popular account of the "residual" (asymptotic) switch cost is that it reflects "task-set inertia": carry-over of task-set parameters from the preceding trial(s). New evidence for a component of "task-set inertia" comes from eye-tracking, where the location associated with the previously (but no longer) relevant task is fixated preferentially over other irrelevant locations, even when preparation intervals are generous. Might such limits in overcoming task-set inertia in general, and "attentional inertia" in particular, result from suboptimal scheduling of preparation when the time available is outside one's control? In the present study, the stimulus comprised 3 digits located at the points of an invisible triangle, preceded by a central verbal cue specifying which of 3 classification tasks to perform, each consistently applied to just 1 digit location. The digits were presented only when fixation moved away from the cue, thus giving the participant control over preparation time. In contrast to our previous research with experimenter-determined preparation intervals, we found no sign of attentional inertia for the long preparation intervals. Self-paced preparation reduced but did not eliminate the performance switch cost-leaving a clear residual component in both reaction time and error rates. That the scheduling of preparation accounts for some, but not all, components of the residual switch cost, challenges existing accounts of the switch cost, even those which distinguish between preparatory and poststimulus reconfiguration processes. (PsycINFO Database Recor
The effect of cytotoxic chemotherapy on the structural and material properties of regenerate bone in a rabbit model of limb lengthening
Abstract: A New Zealand White (NZW) rabbit model was used to investigate the effect of
cyclical cytotoxic chemotherapy on the structural and material properties of
regenerate bone. This attempted to reproduce the biological situation encountered
in a human adolescent with a primary malignant bone tumour, treated by surgical
resection and either adjuvant or neo-adjuvant cyclical chemotherapy with bone
transport to reconstruct the skeletal defect.
General Hypothesis
It is possible to produce normal bone by distraction osteogenesis in the presence
of cyclical cytotoxic therapy.
Materials and Methods: Forty immature male rabbits were divided equally into 2 groups. Each received 2
cycles of either cis-platinum / adriamycin or normal saline, with a tibial osteotomy
and lengthening at 12-weeks of age. The timing of the cytotoxic drugs differed
between groups in an attempt to simulate an adjuvant and neo-adjuvant dose
schedule.
Results: A reproducible animal model was developed, appropriate doses of cis-platinum
and adriamycin were determined and it was demonstrated that surgical
lengthening was possible in animals receiving chemotherapy.
There were no differences in the physical characteristics of the regenerate or
lengthened bone in either arm of the study.
In the group that received 2-cycles of chemotherapy before lengthening (neoadjuvant
group), there was a significant reduction in bone mineral concentration
(BMC), bone mineral density (BMD) and volumetric bone mineral density (vBMD),
assessed by dual X- ray absorptiometry (DXA). There was no effect on the
structural properties assessed by compression testing
In the group that received chemotherapy before and during lengthening (adjuvant
group), there was no effect on mineralisation but a reduction in energy to yield and
yield strain was demonstrated. Conclusion: These findings should be interpreted with caution, as the animals did not have
malignant bone tumours and were given a limited drug regimen. The study did not
demonstrate any consistent effect on the properties of regenerate bone but the
assessment did not include histological analysis. Further work is needed to
investigate the mechanism in which these agents affect distraction osteogenesis
and this will require a dynamic assessment of bone formation and more
sophisticated analysis of regenerate structure
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