汉字识别早期知觉过程中的整体优先效应

以7画、10画、13画上下、左右结构低字频宋体汉字为材料,以整字或成字部件为检测目标,在0～1.5、0～2.0、0～2.5、0～3.0周/度空间频率条件下探讨整体-局部加工的关系.结果发现,空间频率一定时,整字辨别的正确率更高,反应时更短.汉字识别过程中存在着明显的整体优先效应.作者认为,知觉过程由整体加工水平向局部加工水平的转换使部件辨别时间延长、正确率下降;刺激图像中整体性空间信息比较丰富,细节信息相对不足,进一步促成了知觉辨别的整体优先效应.     

Effects of targets embedded within words in a visual search task

Visual search performance can be negatively affected when both targets and distracters share a dimension relevant to the task. This study examined if visual search performance would be influenced by distracters that affect a dimension irrelevant from the task. In Experiment 1 within the letter string of a letter search task, target letters were embedded within a word. Experiment 2 compared targets embedded in words to targets embedded in nonwords. Experiment 3 compared targets embedded in words to a condition in which a word was present in a letter string, but the target letter, although in the letter string, was not embedded within the word. The results showed that visual search performance was negatively affected when a target appeared within a high frequency word. These results suggest that the interaction and effectiveness of distracters is not merely dependent upon common features of the target and distracters, but can be affected by word frequency (a dimension not related to the task demands).     

词素位置概率在中文阅读中的作用：词汇判断和眼动研究

中文词切分的认知机制一直是心理语言学关注的焦点问题之一,研究发现中文读者可使用词素位置概率等语言学线索帮助词切分,而首、尾词素位置概率的重要程度以往研究观点并不一致。本研究通过词汇判断和眼动实验,考察中文读者对首、尾词素位置概率的利用情况。实验1a和1b采用词汇判断任务,考察在不同词频条件下词首与词尾词素位置概率对词汇识别的影响。在错误率和反应时指标上,高频词条件下词首与词尾词素位置概率效应不显著;低频词条件下词首词素位置概率效应显著,词尾词素位置概率效应不显著。实验2a和2b采用句子阅读任务,考察在自然阅读情境中被试对词素位置概率的运用。在凝视时间、回视路径时间和总注视时间指标上,低频词条件下词首词素位置概率效应显著,词尾词素位置概率效应不显著。高频词条件下词首与词尾词素位置概率效应均不显著。词汇判断和眼动证据共同表明,词素位置概率信息是中文读者重要的语言词切分线索,且与词尾词素位置概率相比,词首词素位置概率在词汇切分与识别过程中发挥的作用更大。同时,词素位置概率线索的运用会受到词频的影响,研究结果支持复合词加工的混合通达表征模型。     

Categorizing facial identities, emotions, and genders: attention to high- and low-spatial frequencies by children and adults

Three age groups of participants (5-6 years, 7-8 years, adults) matched faces on the basis of facial identity. The procedure involved either low- or high-pass filtered faces or hybrid faces composed from two faces associated with different spatial bandwidths. The comparison stimuli were unfiltered faces. In the three age groups, the data indicated a significant bias for processing of low-pass information in priority. In a second task, participants were asked to identify the emotion (smiling or grimacing) or gender (male or female) of hybrid high-pass/low-pass faces. Opposite results emerged in the two tasks irrespective of the age group; the gender discrimination task indicated a bias for low-pass information, and the emotion task indicated a bias for high-pass information. These differences suggest independent processing routes for functionally different types of information such as emotion, gender, and identity. These routes are already established by 5 years of age.     

The precise time course of lexical activation: MEG measurements of the effects of frequency, probability, and density in lexical decision

Visually presented letter strings consistently yield three MEG response components: the M170, associated with letter-string processing (Tarkiainen, Helenius, Hansen, Cornelissen, & Salmelin, 1999); the M250, affected by phonotactic probability, (Pylkk?nen, Stringfellow, & Marantz, 2002); and the M350, responsive to lexical frequency (Embick, Hackl, Schaeffer, Kelepir, & Marantz, 2001). Pylkk?nen et al. found evidence that the M350 reflects lexical activation prior to competition among phonologically similar words. We investigate the effects of lexical and sublexical frequency and neighborhood density on the M250 and M350 through orthogonal manipulation of phonotactic probability, density, and frequency. The results confirm that probability but not density affects the latency of the M250 and M350; however, an interaction between probability and density on M350 latencies suggests an earlier influence of neighborhoods than previously reported.     

A strict response criterion yields a mirror effect in the novelty paradigm

According to the novelty/encoding hypothesis (NEH; Tulving & Kroll, 1995), efficacy of encoding information into long-term memory depends on the movelty of the information. Recognition accuracy is higher for novel than for previously familiarized material. This novelty effect is not a mirror effect: the superiority of novel over familiar items is not found in the hit rates but only in the false-alarm rates. The main result in the present replication study was that novel hit rates were higher than familiar ones when the most confident responses were examined separately, and thus a mirror effect could be demonstrated for these data, for both the low- and the high-frequency words. Similarly, the word-frequency effect on hits was stronger when a stricter response criterion was applied. It was concluded that the novelty effect and the word-frequency effect are more similar to one another than has hitherto been thought.     

How pigeons discriminate the relative frequency of events.

This study examined how pigeons discriminate the relative frequencies of events when the events occur serially. In a discrete-trials procedure, 6 pigeons were shown one light nf times and then another nl times. Next, they received food for choosing the light that had occurred the least number of times during the sample. At issue were (a) how the discrimination was related to two variables, the difference between the frequencies of the two lights, D = nf - nl, and the total number of lights in the sample, T = nf + nl; and (b) whether a simple mathematical model of the discrimination process could account for the data. In contrast with models that assume that pigeons count the stimulus lights, engage in mental arithmetic on numerons, or remember the number of stimuli, the present model assumed only that the influence of a sample stimulus on choice increases linearly when the stimulus is presented, but decays exponentially when the stimulus is absent. The results showed that, overall, the pigeons discriminated the relative frequencies well. Their accuracy always increased with the absolute value of the difference D and, for D > 0, it decreased with T. Performance also showed clear recency, primacy, and contextual effects. The model accounted well for the major trends in the data.     

Visual field differences in spatial frequency discrimination

Subjects discriminated between sine-wave gratings that differed by either +/-0.125 octaves (small difference) or +/-1.0 octaves (large difference). Baseline stimuli consisted of either 1.0 or 4.0 cycles per degree gratings. A left visual field advantage was obtained for the small difference in frequency, with no visual field advantages for the large difference in frequency. Similarly, moderate support for right versus left visual field advantages in processing high versus low spatial frequencies was found, although these interactions were not statistically significant. The results are discussed in light of Kosslyn's (1987) categorical and coordinate framework.     

Imagery Value,Subjective and Objective Frequency,Date of Entry into the Language,and Degree of Polysemy in a Sample of 998 French Words

A random sample of 998 lexical words was drawn from a dictionary of the French language. Two groups of subjects rated the words for imagery value (IV) and subjective frequency (SF). Despite substantial individual differences in the ratings, the subjective measures were highly reliable (α = 0.98 for both IV and SF). The relation between the standard deviation and the mean of the ratings can be described by a quadratic function (R = 0.93 for IV and R = 0.75 for SF). The independence of IV and frequency was confirmed. IV was found to be partially dependent on grammatical category (η = 0.50) and slightly dependent on polysemy. Date of entry into the language (DE) was correlated with objective and subjective frequency. The correlation between DE and IV was weak. The words and their characteristics are presented in the Appendix.