Infant auditory perception: Tonal masking

The results of an earlier study (Olsho, 1984) indicated that 5- to 8-month-old infants were relatively better at discriminating among high-frequency pitches than low. In the present study, sensory and nonsensory explanations for that effect were evaluated by examining infants' performance in a task requiring similar sensory processing but differing in the demands placed on processes such as memory. Infants' ability to resolve frequency was tested using a tonal masking paradigm, the psychophysical tuning curve. Twenty-four infants were tested at probe frequencies ranging from 500 to 4000 Hz; a group of young adults served as a comparison. Masked and unmasked thresholds were estimated using the visually reinforced head turn procedure in conjunction with an adaptive psychophysical method. Although infants' tuning curves fell below those of adults (indicating poorer performance), the widths and slopes of the infants' curves were not different from the adults'. Moreover, the difference between age groups remained constant across probe frequencies. These findings imply that by 5 months of age, the infant's ability to resolve sound frequency is similar to the adult's.     

Fitting cross-classification table data to models when observations are subject to classification error

Individuals are classified in a cross-classification table where two behavioral observations on each individual determine the classification. The problem is to test certain structural models assumed to underlie the cross-classified observations. A minimum chi-square test procedure is proposed.     

腔内泌尿外科若干技术的评价

随着高科技的发展,通过各种多功能的内镜技术,已可将电、激光、超声及机械力转入到整个泌尿系统的腔道内,不仅可以诊断疾病,还可以治疗疾病。回顾腔内泌尿外科的发展历史,社会实践的需要是腔内泌尿外科发展的根本动力,科学技术进步推动医学的发展,高新技术促进了腔内泌尿外科的迅速发展。     

理性看待微创外科

所谓“微创”,乃是传统外科发展的伸延和提升。微创不等于无创,微创需要科学的决策,同时微创要运用循证医学。微创具有广阔的前景,但它的治疗之路依然很长。它需要进一步的完善。目前,还不是丰收的季节。     

医疗社会工作：现实意义和发展趋向

医疗社会工作是社会工作专业的重要实务领域之一,在西方发达国家的医疗事业中扮演着不可替代的角色,具有解决患者及其家属问题、处理医患关系,并促进公共卫生政策的改善等多种功能。从我国目前的发展来看,尚处于起步阶段,还有诸多需要努力的方面,包括完善相关政策、提高服务质量、修正教育模式、突出中国特色等。     

阅读流畅性研究及其进展

从介绍两个阅读发展模型入手,探讨了阅读流畅性与阅读的关系,揭示阅读流畅性在阅读发展进程中的地位和作用,并介绍了影响阅读流畅性的因素。在此基础上,指出了阅读流畅性研究对语言认知研究的重要性,并对今后研究作了初步展望。     

智障儿童和正常儿童外显记忆与内隐记忆的比较研究

本实验采取加工分离程序(PDP)对38名弱智儿童的外显记忆与内隐记忆进行研究,并与47名正常儿童进行比较,结果认为:(1)正常儿童外显记忆明显优于弱智儿童,但在内隐记忆方面,正常儿童与弱智儿童没有显著差异;(2)本实验中,年龄对内隐记忆和外显记忆均没有影响。研究结果对弱智儿童的教育方面有启示作用;另外,PDP实验由于其本身的复杂性,在对特殊人群进行施测时,需要特别注意。     

经验、材料性质及加工水平对虚假记忆的影响

本实验采用DRM研究范式,考察经验、材料性质和加工水平三个方面对虚假记忆的影响。实验首次采用句子的方式呈现,给被试提供符合经验和不符合经验的句子进行学习和再认。实验结果显示,三个因素对虚假记忆的影响都是显著的,其中,经验是导致虚假记忆产生的主导因素,加工深度同经验之间以及材料性质同经验之间的交互作用均存在显著的交互作用。     

A common representational system governed by Weber's law: nonverbal numerical similarity judgments in 6-year-olds and rhesus macaques

This study compared nonverbal numerical processing in 6-year-olds with that in nonhuman animals using a numerical bisection task. In the study, 16 children were trained on a delayed match-to-sample paradigm to match exemplars of two anchor numerosities. Children were then required to indicate whether a sample intermediate to the anchor values was closer to the small anchor value or the large anchor value. For two sets of anchor values with the same ratio, the probability of choosing the larger anchor value increased systematically with sample number, and the psychometric functions superimposed when plotted on a logarithmic scale. The psychometric functions produced by the children also superimposed with the psychometric functions produced by rhesus monkeys in an analogous previous experiment. These examples of superimposition demonstrate that nonverbal number representations, even in children who have acquired the verbal counting system, are modulated by Weber's law.     

Specific phonological impairments in dyslexia revealed by eyetracking

Phonological deficits in dyslexia are typically assessed using metalinguistic tasks vulnerable to extraneous factors such as attention and memory. The present work takes the novel approach of measuring phonology using eyetracking. Eye movements of dyslexic children were monitored during an auditory word recognition task in which target items in a display (e.g., candle) were accompanied by distractors sharing a cohort (candy) or rhyme (sandal). Like controls, dyslexics showed slower recognition times when a cohort distractor was present than in a baseline condition with only phonologically unrelated distractors. However, unlike controls, dyslexic children did not show slowed recognition of targets with a rhyme distractor, suggesting they had not encoded rhyme relationships. This was further explored in an overt phonological awareness test of cohort and rhyme. Surprisingly, dyslexics showed normal rhyme performance but poorer judgment of initial sounds on these overt tests. The results implicate impaired knowledge of rhyme information in dyslexia; however they also indicate that testing methodology plays a critical role in how such problems are identified.