On the Construction and Maintenance of Expectancies

1978 ◽  
Vol 30 (3) ◽  
pp. 441-454 ◽  
Author(s):  
John P. McLean ◽  
Gordon L. Shulman

Reaction time techniques were used to examine the role of attention in the construction and maintenance of expectancies. In Experiment I, a primed letter matching task, expectancies were observed through a delay (cost) in responding to misprimed letter arrays. A secondary probe task was interpolated between prime and array letters on some of the trials, with attentional demands inferred from delayed responding to probes. By varying the amount of time between onset of the prime and either a probe or letter array, it was found that there is attentional involvement (as reflected in probe inhibition) prior to the observation of expectancies (as reflected in letter matching cost). It was also found that the interpolation of an attention-demanding probe task did not entirely disrupt primed expectancies. Experiment II found that an expectancy persists even when an interpolated distractor task signals that the expectancy is no longer valid. These expectancies were found to decay as a function of time. The implications of these results for attention allocation and memory activation views of expectancy were discussed.

2019 ◽  
Author(s):  
Je-Ruei Wen ◽  
Benjamin Roman ◽  
Freddy Rodriguez Ortiz ◽  
Noel Mireles Villegas ◽  
Nicholas Porcellino ◽  
...  

Lack of detailed understanding of the growth mechanism of CsPbBr3 nanocrystals has hindered sophisticated morphological and chemical control of this important emerging optoelectronic material. Here, we have elucidated the growth mechanism by slowing the reaction kinetics. When 1-bromohexane is used as an alternative halide source, bromide is slowly released into the reaction mixture, extending the reaction time from ~3 seconds to greater than 20 minutes. This enables us to monitor the phase evolution of products over the course of reaction, revealing that CsBr is the initial species formed, followed by Cs4PbBr6, and finally CsPbBr3. Further, formation of monodisperse CsBr nanocrystals is demonstrated in a bromide-deficient and lead-abundant solution. The CsBr can only be transformed into CsPbBr3 nanocubes if additional bromide is added. Our results indicate a fundamentally different growth mechanism for CsPbBr3 in comparison with more established semiconductor nanocrystal systems and reveal the critical role of the chemical availability of bromide for the growth reactions.<br>


2015 ◽  
Vol 43 (2) ◽  
pp. 310-337 ◽  
Author(s):  
MARCEL R. GIEZEN ◽  
PAOLA ESCUDERO ◽  
ANNE E. BAKER

AbstractThis study investigates the role of acoustic salience and hearing impairment in learning phonologically minimal pairs. Picture-matching and object-matching tasks were used to investigate the learning of consonant and vowel minimal pairs in five- to six-year-old deaf children with a cochlear implant (CI), and children of the same age with normal hearing (NH). In both tasks, the CI children showed clear difficulties with learning minimal pairs. The NH children also showed some difficulties, however, particularly in the picture-matching task. Vowel minimal pairs were learned more successfully than consonant minimal pairs, particularly in the object-matching task. These results suggest that the ability to encode phonetic detail in novel words is not fully developed at age six and is affected by task demands and acoustic salience. CI children experience persistent difficulties with accurately mapping sound contrasts to novel meanings, but seem to benefit from the relative acoustic salience of vowel sounds.


2004 ◽  
Vol 77 (5) ◽  
pp. 891-913 ◽  
Author(s):  
Pankaj Y. Patil ◽  
William J. van Ooij

Abstract Adhesion between rubber and brass-coated steel cords is enhanced by using resins as adhesion promoters. Experiments were carried out using a squalene liquid rubber modeling approach to study the effect of resins on the chemistry of the vulcanization reaction. The formation of new intermediates during vulcanization and changes in chemical concentrations with reaction time was studied using Gel Permeation Chromatography (GPC) analysis of the reacted squalene mixtures. Also, the effect of presence of resins on the surface of sulfidized brass cords was studied by analyzing the adhesion layer's elemental composition using the Electron Dispersive X-ray Spectroscopy (EDX) and Secondary Ion Mass Spectrometry (SIMS) characterization techniques. The changes in surface morphology of the adhesion layer with reaction time was noted by taking micrographs using the Scanning Electron Microscopy (SEM) technique. In this paper, a new mechanism is proposed for the role of resins in the improvement of initial and aged adhesion performance between rubber and brass-coated steel tire cords.


2020 ◽  
Author(s):  
Jon Prince ◽  
Dominique T Vuvan ◽  
Mark A. Schmuckler ◽  
Thomas T. Scott-Clark

Research on tonal priming has consistently shown that tonally expected events are processed more efficiently and has confirmed that the locus of the effect is cognitive rather than sensory. However, it is also important to investigate the role of pitch height, because models of tonal priming collapse across octaves, yet it is possible that pitch height may modulate the effectiveness of tonal priming. We systematically tested this issue by varying the pitch heights of a related (tonic) or a less-related (subdominant) target chord following a tonal context. Musically untrained participants (N = 30) made speeded consonant/dissonant judgments of the final chord of an eight-chord sequence. The effects of tonal priming emerged in accuracy and reaction time measures for all octaves, except for a ceiling effect on accuracy in the matching (original pitch height) condition. In a second experiment, we increased the shift to two octaves and compressed the chords to eliminate overlap between the target and context chords; again, tonal priming emerged. These findings have implications for the behavioral study of tonal priming and support the assumption of octave equivalence in computational models.


2018 ◽  
Author(s):  
Anna K Bobak ◽  
Viktoria Roumenova Mileva ◽  
Peter Hancock

The role of image colour in face identification has received little attention in research despite the importance of identifying people from photographs in identity documents (IDs). Here, in two experiments, we investigated whether colour congruency of two photographs shown side by side affects face matching accuracy. Participants were presented with two images from the Models Face Matching Test (Experiment 1) and a newly devised matching task incorporating female faces (Experiment 2) and asked to decide whether they show the same person, or two different people. The photographs were either both in colour, both in grayscale, or mixed (one in grayscale and one in colour). Participants were more likely to accept a pair of images as a “match”, i.e. same person, in the mixed condition, regardless of whether the identity of the pair was the same or not. This demonstrates a clear shift in bias between “congruent” colour conditions and the mixed trials. In addition, there was a small decline in accuracy in the mixed condition, relative to when the images were presented in colour. Our study provides the first evidence that the hue of document photographs matters for face matching performance. This finding has important implications for the design and regulation of photographic ID worldwide.


2009 ◽  
Vol 3 (5-6) ◽  
pp. 101-108
Author(s):  
Éva Bácsné Bába

The role of the time factor in management is increasing. Change directs attention to the time factor from the point of view of the organisation,and management does the same from that of the person. I examined the time management practice of managers of organisations related to agribusiness, and the reaction time characterising the adaption ability of the organisations through a questionnaire survey. I analysed the collected data with scientifically established statistical methods. During studying resources, managing tasks, change, reaction time and effect I explored the features of time as resource, the significance of the time factor, the improvability of time efficiency in the different managing functions, the factors supporting and hindering the quick reaction of organisations, and what rearrangements can be seen in management work nowadays.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Lindsay Portnoy ◽  
Talia Lemberger

Purpose Approaches to learning have the ability to influence knowledge acquisition, comprehension, retention and even motivation to learn. Previous work indicates that despite age, experience, or prior knowledge, students have a tendency to approach learning differently as a function of the presented content. The purpose of this study is to explore how context influences student approaches to learning science. Design/methodology/approach The authors adopt a question-asking methodology to evaluate if approaches to learning the same science content vary when presented within the context of Pure Science or the History of Science. Findings Results indicate that contextualizing the presentation of science content, shifts the approaches students take in attempting to learn science content as evidenced by the questions they ask to deepen their understanding. Additional variables of prior experience with each scientific concept, task persistence at a distractor task and later recall of the presented concepts were related to different inquiry strategies. Research limitations/implications Implications for instructional design and pedagogy are discussed. Practical implications The framework in which scientific information is presented may impact how students modify existing and create a new schema, impacting their beliefs about scientific knowledge and the way in which students question, hypothesize and engage within the domain of science. Social implications By studying the role of inquiry while students engage in science learning, the authors explore the role of context, content and knowledge retention. Originality/value The current study probes at the nature of student questioning and its reliance on the content, context and its relationship to outcome variables such as learning and, perhaps, even persistence as it relates to students’ prior knowledge within content areas which may, in turn, lead to varying levels of student self-efficacy.


Languages ◽  
2019 ◽  
Vol 4 (2) ◽  
pp. 33
Author(s):  
Hanako Yoshida ◽  
Aakash Patel ◽  
Joseph Burling

This study evaluated two explanations for how learning of novel adjectives is facilitated when all the objects are from the same category (e.g., exemplar and testing objects are all CUPS) and the object category is a known to the children. One explanation (the category knowledge account) focuses on early knowledge of syntax–meaning correspondence, and another (the attentional account) focuses on the role of repeated perceptual properties. The first account presumes implicit understanding that all the objects belong to the same category, and the second account presumes only that redundant perceptual experiences minimize distraction from irrelevant features and thus guide children’s attention directly to the correct item. The present study tests the two accounts by documenting moment-to-moment attention allocation (e.g., looking at experimenter’s face, exemplar object, target object) during a novel adjective learning task with 50 3-year-olds. The results suggest that children’s attention was guided directly to the correct item during the adjective mapping and that such direct attention allocation to the correct item predicted children’s adjective mapping performance. Results are discussed in relation to their implication for children’s active looking as the determinant of process for mapping new words to their meanings.


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