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1.
In adult listeners, the signal-to-noise ratio at masked threshold remains constant with increases in masker level over a wide range of stimulus conditions. This relationship was examined in 7-month-old infants by obtaining masked thresholds for .5- and 4-kHz tones presented in four levels of continuous masking noise. Adults were also tested for comparison. Masker spectrum levels ranged from 5 to 35 dB/Hz for .5-kHz tones, and from ?5 to 25 dB/Hz for 4-kHz stimuli. Thresholds were determined for stimuli of both 10 and 100 msec in duration. The results indicated that infants’ performance was more adultlike for 4-kHz stimuli. Although mean thresholds for both 10- and 100-msec, 4-kHz tones were approximately 7 dB higher in infants than in adults, E/N0 at threshold remained essentially constant over the 30-dB range of maskers employed. By contrast, infants’ thresholds for .5-kHz tones were exceptionally high at lower levels of the masker. Threshold E/N0 decreased significantly as masker level increased from 5 to 35 dB/Hz, and this decrease was significantly greater for 10- than for 100-msec stimuli. Temporal summation of .5-kHz tones, measured as the difference between thresholds obtained at the two signal durations, was greater for infants than for adults at low levels of the masker. However, because infants’ thresholds improved more rapidly with level for 10- than for 100-msec tones, age differences in temporal summation were no longer significant when masker spectrum level was 35 dB/Hz. These results suggest that the relationship between signal-to-noise ratio at masked threshold and level of the masker is dependent on both signal frequency and duration during infancy.  相似文献   

2.
This study examined the effects of an Islamic-based expressive gratitude strategy in comparison to a secular-based expressive gratitude strategy and a control group in enhancing Muslims’ level of happiness. It was hypothesised that practising the Islamic-based gratitude exercise (by associating blessings with Allah) would result in higher happiness level over time, compared to the happiness level of Muslim participants practising the secular-based gratitude exercise (without specific association) or the control group (attending to details of daily life). Sixty students were randomly assigned into one of three groups and over a period of 16 days were asked to practise the respective exercises daily. They were assessed for pre- and post-happiness measures. Results generally supported the hypothesis, and suggested that the Islamic-based gratitude is beneficial in raising participants’ happiness level, as it fits with their beliefs and values. Implications of the results for including Islamic-oriented intervention to promote Muslim happiness are discussed.  相似文献   

3.
A. S. Reber's (1992) proposition that the implicit learning system should demonstrate invariance of intellectual level (IQ) was examined by comparing 20 children with intellectual disability (mean mental age [MA] = approximately 5.8 years) with 20 intellectually gifted children (mean MA = approximately 12.4 years) of similar chronological age (CA; approximately 9.5 years). Implicit learning was assessed using a task involving covariation of 2 incidental cues. Explicit learning was assessed using a task of similar logical structure. Contrary to the IQ-invariance proposition, implicit learning as well as explicit learning varied with intellectual level. A secondary aim was to distinguish the contributions of CA, IQ, and MA to implicit learning. This was done by combining the samples of children in the present study with 2 samples of younger and older children of average ability from a study by M. Maybery, M. Taylor, and A. O'Brien-Malone (1995). Analyses showed that MA is critical to implicit learning.  相似文献   

4.
《Cognitive development》1988,3(3):247-264
A common assumption in the developmental literature is that the earliest kind of conceptual categories to be formed are basic-level categories. A corollary assumption is that superordinate categories are formed after, and out of, previously acquired basic-level categories. Two experiments using an object-manipulation task explored these assumptions by studying response to a variety of categories in children aged from 12 to 20 months. The first experiment examined responses to basic-level categories (dogs vs. cars),superordinate categories (animals vs. vehicles), and contextual categories (kitchen things vs. bathroom things). At all ages tested, the children performed best on the basic-level categories but, even at 12 months of age, some children were responsive to the superordinate and contextual categories. By 20 months of age, approximately half of the children showed such sensitivity. The second experiment showed that 16- and 20-month-olds differentiated basic-level categories only when the categorical contrasts were taken from different superordinate classes (e.g., dogs vs. cars) and not when the categories were drawn from the same superordinate class (e.g., dogs vs. horses). The data suggest that basic-levels categories are not the first kind of conceptual categories to be formed. Instead, it appears that children may form more global categories, with basic-level differentiation occurring later.  相似文献   

5.
Several recent studies have shown that the upper part of words is more important than the lower part in visual word recognition. Here, we examine whether or not this advantage arises at the lexical or at the letter (letter feature) level. To examine this issue, we conducted two lexical decision experiments in which words/pseudowords were preceded by a very brief (50-ms) presentation of their upper or lower parts (e.g., ). If the advantage for the upper part of words arises at the letter (letter feature) level, the effect should occur for both words and pseudowords. Results revealed an advantage for the upper part of words, but not for pseudowords. This suggests that the advantage for the upper part of words occurs at the lexical level, rather than at the letter (or letter feature) level.  相似文献   

6.
Children born preterm have poorer outcomes than children born full-term, but the caregiving environment can ameliorate some of these differences. Recent research has proposed that preterm birth may be a plasticity factor, leading to better outcomes for preterm than full-term infants in higher quality environments. This analysis uses data from two waves of an Irish study of children (at 9 months and 3 years of age, n = 11,134 children) and their caregivers (n = 11,132 mothers, n = 9998 fathers) to investigate differences in how caregiving affects social, cognitive, and motor skills between full-term, late preterm, and very preterm children. Results indicate that parental emotional distress and quality of attachment are important for child outcomes. Both being born very preterm and late preterm continue to be risk factors for poorer outcomes at 3 years of age. Only fathers’ emotional distress significantly moderated the effect of prematurity on infants’ cognitive and social outcomes—no other interactions between prematurity and environment were significant. These interactions were somewhat in line with diathesis stress, but the effect sizes were too small to provide strong support for this model. There is no evidence that preterm birth is a plasticity factor.  相似文献   

7.
Salthouse TA 《Intelligence》2012,40(4):352-361
Longitudinal change in five cognitive abilities was investigated to determine if the direction or magnitude of change was related to the individual's ability level. Adults between 18 and 97 years of age performed three versions of 16 cognitive tests on two occasions separated by an average of 2.7 years. In order to control for influences associated with regression toward the mean, level of ability was determined from scores on the first version of the cognitive tests on the first occasion, and across-occasion change was examined on the second and third versions. Change in every cognitive ability was significantly more negative with increased age. However, there was little indication of ability-dependent change in any of the five cognitive abilities, either in differences between composite scores, or in estimates of latent change. Although there are reasons to expect cognitive change to be less negative at either high or low levels of ability, these data suggest that neither the direction nor magnitude of change is related to initial ability when influences of regression toward the mean are controlled.  相似文献   

8.
Two groups of primary level schoolchildren were asked to listen to recordings of a familiar story. One recording was of fluent speech and the second of stuttered speech. Group I, composed of 30 children in the first and second grades, was able to differentiate between stuttered and fluent speech, but did not label disfluent behavior as “stuttering.” Group II, composed of 30 children in the third and fourth grades, not only differentiated the samples, but showed a tendency to label the disfluent behavior “stuttering.” Both groups indicated a preference for the fluent sample.  相似文献   

9.
10.
Several researchers have investigated the possibility that people indeed can love individuals who are engaged in behaviors that are considered unacceptable. In the present research, the authors evaluated the possibility that people distinguish between presumably sinful persons and presumably sinful behaviors at a cognitive level that does not involve conscious intent and awareness: the implicit (nonconscious) level of awareness. Participants performed a speeded-response task, the Implicit Association Test. Results indicated that participants were able to make such a (person vs. behavior) distinction and that in doing so, they manifested positive implicit evaluations of sinful people relative to sinful actions.  相似文献   

11.
A paucity of research has directly compared empirically supported interventions to examine their effectiveness among students with different mathematics fluency skills. The purpose of this study was to compare the effects of two empirically supported interventions and a control condition on the mathematics fluency of 98 second and third grade students. Specifically, effects of explicit timing and cover-copy-compare on subtraction fluency were examined each session, which occurred twice weekly for a total of six weeks. HLM was used to examine progress during the intervention sessions and determine the effect of initial fluency level on intervention effectiveness. Results suggested students' initial level of fluency impacted intervention effectiveness. That is, for students whose fluency levels fell within the frustrational range CCC and control conditions resulted in the best performance over time but for children whose fluency was in the instructional range explicit timing was the most effective treatment.  相似文献   

12.
A study of 494 employees nested in workgroups from 19 different organizations revealed group identification to be an important factor influencing work-related bullying at both the individual and the group level. Results show that the more employees identified with their group, the less likely they were victims of bullying, which is in line with previous social identity-based analyses of work stress. More importantly, the higher the average level of group identification in the organization, the lower the odds of being a victim versus not being a victim. The latter effect constituted a genuine context effect. These findings redress a neglect of the social bases of workplace bullying and suggest that bullying needs to be understood within a broader perspective of workgroup identities.  相似文献   

13.
Since Berger’s discovery of the electroencephalogram (EEG), its analysis has been generally restricted to the visual range (upmost 100Hz) and has ignored higher frequency components. One reason should be that there are no reliable methods to distinguish the brain potentials from muscle activity. We have introduced fluctuation analysis, which is popular method especially in the field of basic physiology to clinical electrophysiology. In our previous study, it was declared that power spectral density (PSD) of human high frequency EEG was composed of double Lorentzians and vanished into white level within 1kHz. Then the purpose of this study is to elucidate the “Automated Fluctuation Analysis,” which enables us to evaluate these higher frequency components and its physiological meaning especially focused on conscious level from wakefulness to sleep stage 1. Seventy-four scalp recording EEGs in twenty normal subjects were studied. In short, “Automated Fluctuation Analysis” is made of three steps: amplification of EEG signal, A/D conversion and Fast Fourier Transform by signal processor and extraction of Lorentzian parameters. PSD of high frequency EEG was displayed on log-log graph and the algorithm fit to the following Lorentzian formula were mathematically based on Brown & Dennis. S(f)=S1/ [1+(f/fc1)2] + S2/ [1+(f/fc2)2], where S(f) is PSD (μ V2/Hz) at each frequency (f;Hz), S1 and S2 are the plateau level or zero-frequency power of the initial and second Lorentz, and fc1 and fc2 are the corner or half-power frequency of the initial and second Lorentz, respectively. As results, during wakefulness the PSD of high frequency EEG activity was composed of double Lorentzian fluctuations and the power distribution of S1 value in topographical display was frontal dominant. This pattern of S1 value disappeared and S2 value became lower during sleepiness and the second Lorentz disappeared during sleep.  相似文献   

14.
The experiment was designed to test differential predictions derived from dual-coding and depth-of-processing hypotheses. Subjects under incidental memory instructions free recalled a list of 36 test events, each presented twice. Within the list, an equal number of events were assigned to structural, phonemic, and semantic processing conditions. Separate groups of subjects were tested with a list of pictures, concrete words, or abstract words. Results indicated that retention of concrete words increased as a direct function of the processing-task variable (structural < phonemic 相似文献   

15.
Educational policy is often based on the assumption that redundancy is a negative factor in dissemination and should be eliminated in order to achieve cost effectiveness. This article examines issues of redundancy in three dissemination contexts: knowledge acquisition and storage; knowledge synthesis; and knowledge utilization. Knowledge utilization and implementation, ultimately the goals of federally supported dissemination efforts, should rely on processes of planned and targeted redundancy of knowledge syntheses to various users. Barbara Lieb is research director, Research Applications Division of the Office of Educational Research and Improvement, U.S. Department of Education, where she formerly managed the the Regional Educational Laboratory Program. Having published and taught extensively in the areas of interpersonal, organizational, and instructional communication, she brings a communication perspective to issues of knowledge utilization. In addition to managing other federally supported dissemination programs for the National Institute of Education, she has served in executive capacities for both the Speech Communication Association and the American Society for Medical Technology, dealing with issues of professional development and knowledge use.  相似文献   

16.
The café wall pattern is composed of rows of alternating light and dark tiles, and alternate rows are shifted by one fourth of a cycle. The rows of tiles are separated by narrow horizontal mortar lines whose luminance is between those of the dark and the light tiles. Although the mortar lines are physically parallel, they are perceived to be tilted, which is known as the café wall illusion. In this study, an energy-based model for encoding orientation is implemented in order to estimate the strength of the café wall illusion, and it is shown that the estimated orientation depends on the spatial frequency to which each orientation-encoding unit is tuned. The estimation of mortar line orientation from an orientation-encoding unit tuned to a lower spatial frequency was greater than that from a unit tuned to a higher spatial frequency. It is assumed that the perceived mortar line orientation is the result of an integration of responses from the orientation-encoding units tuned to various spatial frequencies. This leads to the prediction that under viewing conditions in which responses from orientation-encoding units tuned to a higher spatial frequency are presumably weakened, the strength of the café wall illusion increases. In agreement with this prediction, it is shown that the café wall illusion is stronger when the café wall image is presented at the periphery or is observed under low luminance levels. On the other hand, the weighted averaging of the estimated mortar orientations across spatial frequencies overestimates the perceived orientation of the mortar lines. This suggests that the final percept of the café wall illusion could be determined by some kind of nonlinear interaction, such as an inhibitory interaction, between orientation-encoding units.  相似文献   

17.
In three experiments, the perception of the apparent orientation of block letters shown in various orientations above the subject’s head in the horizontal plane was examined. A block letter F with its front facing down toward the observer has two crossbars on its right side; the top is the part with the long crossbar, and the base has no bar. The experiments involved changing the locations of these parts with respect to the observer. In Experiment 1, the subjects using touch most often identified a letter as having its left and right sides in a normal orientation if the front of the block letter faced upwards away from the observer, with the bar on the right and the top of the letter farther from the subject than the letter’s base. In Experiment 2, the subjects judging visualuprightness favored positions in which the bars were on the right, the top of the block letter was near them, and the letter’s front faced downwards toward the observer. In Experiment 3, the subjects using touch most often assessed letters as being upright if the top of the letter was the farthest part and the bar was on the right. The results suggest that, when assessing orientation, subjects using touch favored positions that would be reached by a letter moving vertically upwards from table height, but subjects relying on vision favored positions reached by a letter moving in an arc centered on the subject’s head (on the eyes, in particular).  相似文献   

18.
Cultural norms of behaviour influence desirable and problematic behaviours of individuals. In particular, cultural norms should influence individuals' dishonesty. In a recent Nature study, prevalence of rule violations was introduced as a new country‐level measure of behavioural norms. However, information on individuals' actual honesty was not available due to characteristics of the experimental design. Overcoming this limitation, we show that country‐level behavioural norms are related to individual‐level knowledge overclaiming behaviour (i.e., claiming to know concepts that do not exist, a measure of individuals' actual behavioural dishonesty) among 290,954 students from 57 countries (from the 2012 PISA study). Our study represents a crucial test of the argument that cultural norms influence individual's behaviour and of the validity of the measurement of countries' prevalences of rule violations. These results imply that shaping the behaviour of today's students may result in new behavioural norms that emphasise honesty and rule adherence more strongly.  相似文献   

19.
The current study examined whether juvenile firesetting represents a unique syndrome or an advanced level of antisocial behavior. Thirty-six incarcerated juvenile delinquents, all of whom met criteria for a diagnosis of Conduct Disorder, served as subjects and were categorized into one of three groups: firesetters, non-firesetters but comparable to firesetters in number of conduct disorder symptoms, and non-firesetters who displayed fewer conduct disorder symptoms than the other two groups. Caregivers completed the Child Behavior Checklist on the youth to provide information about the severity and range of psychopathology. The results indicated that firesetters and non-firesetters who had a comparable number of symptoms did not differ from one another on the CBCL subscales of adolescent psychopathology but both differed from the group with fewer symptoms. These results suggest that firesetting does represent an advanced level of antisocial behavior, but that firesetting is not a unique syndrome, at least not in terms of caretakers' perceptions of the youths' problematic behavior. Implications for treatment of firesetters are presented.  相似文献   

20.
The issue of social justice and how it unfolds in the lives of persons seeking counselling has been steadily gaining attention in recent times. This development marks a departure from an individualistic perspective that construes problems as functions of personal deficits, thereby overlooking the many social inequities that contribute to the challenges people face. The turn towards social justice manifests primarily in a call for advocacy on behalf of therapy clients. While celebrating these developments, this article suggests that it is not just in interactions outside the consulting room that injustices may be perpetrated. The author invites attention to the ways in which social justice, or the lack thereof, can be understood to unfold within counselling conversations.  相似文献   

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