Image generation in a letter-classification task

Subjects classified briefly presented uppercase letters as belonging to the first or second half of the alphabet. A prior alternative preceded each target letter by 200 or 1,400 msec. It was either an ampersand (control), a lowercase letter (opposite case), or an uppercase letter (same case). In the latter two conditions, the target was equally likely to be identical in name to the prior alternative or from the opposite half of the alphabet. For the 200-msec onset asynchrony, classification accuracy was greater in the same-case condition than in the other two conditions, which did not differ. For the 1,400-msec onset asynchrony, accuracy in both the same- and opposite-case conditions was greater than accuracy in the control condition. Same- and opposite-case prior alternatives always biased subjects toward classifying the target in the same half of the alphabet as the alternative. The accuracy results suggest that internally generated images can be used to aid target classification in the opposite-case condition.     

Lexical decision in a phonologically shallow orthography

The Serbo-Croatian language is written in two alphabets, Roman and Cyrillic. Both orthographies transcribe the sounds of the language in a regular and straightforward fashion and may, therefore, be referred to as phonologically shallow in contrast to English orthography, which is phonologically deep. Most of the alphabet characters are unique to one alphabet or the other. There are, however, a number of shared characters, some of which receive the same reading and some of which receive a different reading, in the two alphabets. It is possible, therefore, to construct a variety of types of letter strings. Some of these can be read in only one way and can be either a word or nonsense. Other letter strings can be pronounced one way if read as Roman and in a distinctively different way if read as Cyrillic and can be words in both alphabets—but different words; or they can be nonsense in both alphabets or nonsense in one alphabet and a word in the other. In a lexical decision task conducted with bialphabetical readers, it was shown that words that can be read in two different ways are accepted more slowly and with greater error than words that can be read only one way. It was concluded that for the phonologically shallow writing systems of Serbo-Croatian, lexical decision proceeds with reference to the phonology.     

Visual vs. verbal stimulus set in a letter-classification task

In three experiments, subjects classified briefly presented letters as belonging to either the first or the second half of the alphabet. Prior to each target letter, the subjects were given either a verbally named letter (verbal set), a letter presented visually for 3 sec (visual set), or no prior alternative (control). The target was equally likely to be the same as the prior alternative (same trials) or from the opposite half of the alphabet (different trials). Classification accuracy was always greater for visual set than for the control condition. Verbal-set accuracy was no better than control accuracy when the verbal alternative immediately preceded the target but was equal to visual-set accuracy when the alternative preceded the target by 3 sec. In both set conditions, subjects tended to choose the same half of the alphabet as the prior alternative. It was concluded that type and timing of prior alternatives are important variables in accounting for enhanced classification accuracy.     

Interactions among levels of processing

This article examines associations among representations of physical, name, and category information by determining effects of category repetition on and following physical, name, and category match trials. Subjects decided whether two letters were from the same half of the alphabet. Category repetition effects were evidenced by faster ~nd more accurate responses when letters from the same half of the alphabet were used on successive trials. Although physical matches showed no effect of category repetition, name and category matches did. Trials following physical matches were less affected by category repetition than were trials following name or category matches. The results suggested that these category repetition effects were mediated by interletter associations: Reaction time increased with the alphabetic distance between preceding and current letters. However, these distance effects held only for forward (A → B) and not backward (B → A) alphabetic sequences, suggesting that the alphabetic representation is ordinal and unidirectional.     

Preferring alphabet–keyboard compatibility: Congruency between spatial codes shapes the affective connotation of letters

When letters are encountered, two spatial stimulus codes resulting from their positions within the alphabet and on the computer keyboard are activated mentally. If these two spatial codes match, letter processing is more efficient. The present study tested whether the processing fluency gain resulting from alphabet–keyboard compatibility also enhances affective evaluations of letters. In Experiment 1, participants preferred alphabet–keyboard compatible over incompatible letters in a forced-choice preference rating. Similarly, in Experiment 2, liking ratings for alphabet–keyboard compatible letters were higher compared to incompatible letters. Moreover, in Experiment 3, preference ratings of non-words were positively correlated with the relative number of alphabet–keyboard compatible letters within these letter strings. These findings suggest that alphabet–keyboard compatibility shapes the affective connotation of letters. Moreover, this processing fluency–valence association is activated at the level of letters as well as whole letter strings.     

Categorization and abstraction abilities in 3-year-old children: a comparison with monkey data

Three-year-old children were tested on three categorization tasks of increasing levels of abstraction (used with adult baboons in an earlier study): the first was a conceptual categorization task (food vs toys), the second a perceptual matching task (same vs different objects), and the third a relational matching task in which the children had to sort pairs according to whether or not the two items belonged to the same or different categories. The children were tested using two different procedures, the first a replication of the procedure used with the baboons (pulling one rope for a category or a relationship between two objects, and another rope for the other category or relationship), the second a task based upon childrens prior experiences with sorting objects (putting in the same box objects belonging to the same category or a pair of objects exemplifying the same relation). The children were able to solve the first task (conceptual categorization) when tested with the sorting into boxes procedure, and the second task (perceptual matching) when tested with both procedures. The children were able to master the third task (relational matching) only when the rules were clearly explained to them, but not when they could only watch sorting examples. In fact, the relational matching task without explanation requires analogy abilities that do not seem to be fully developed at 3 years of age. The discrepancies in performances between children tested with the two procedures, with the task explained or not, and the discrepancies observed between children and baboons are discussed in relation to differences between species and/or problem-solving strategies.     

Dividing lines at the word boundary position helps reading in Chinese

Unlike in English, the Chinese printing and writing systems usually do not respect a word boundary when they split lines; thus, characters belonging to a word can be on two different lines. In this study, we examined whether dividing a word across two lines interferes with Chinese reading and found that reading times were shorter when characters belonging to a word were on a single line rather than on adjacent lines. Eye movement data indicated that gaze durations in a region around the word boundary were longer and fixations were closer to the beginnings and ends of the lines when words were split across lines. These results suggest that words are processed as a whole in Chinese reading, so that word boundaries should be respected when deciding how to split lines in the Chinese writing system. They also suggest that the length of return sweeps in reading can be cognitively guided.     

Object-based representations govern both the storage of information in visual short-term memory and the retrieval of information from it

Interest is growing in how information is retained in visual short-term memory (VSTM). We describe an experiment that assesses VSTM within the context of multidimensional signal detection theory. On every trial, participants were presented with a 250-ms display containing four colored shapes. They were then probed 900 ms later with a colored shape and made separate old/new judgments about the color and the shape. In any particular trial, one, both, or neither of the probed features had been presented. Performance differed according to whether both probed features belonged to a single object or to two different objects. When both probed features belonged to the same object, featural retrieval was better than would be predicted by independent feature storage. When both probed features belonged to two different objects, featural retrieval was worse than would be predicted by independent feature storage. We conclude that storage in and retrieval from VSTM operate on the basis of object-based representations.     

Enantiomorphy through the looking glass: literacy effects on mirror-image discrimination

To examine whether enantiomorphy (i.e., the ability to discriminate lateral mirror images) is influenced by the acquisition of a written system that incorporates mirrored letters (e.g., b and d), unschooled illiterate adults were compared with people reading the Latin alphabet, namely, both schooled literate adults and unschooled adults alphabetized in adulthood. In various sorting and same-different comparison tasks with nonlinguistic materials, illiterate participants displayed some sensitivity to enantiomorphic contrasts but performed far worse than all the other participant groups when the task required paying attention to such contrasts. The difficulties of illiterate participants were more severe with enantiomorphs than with rotations in the plane or shape contrasts. Learning a written system that incorporates enantiomorphic letters thus pushes the beginning reader to break the mirror invariance characteristic of the visual system, and this process generalizes beyond the realm of symbolic characters.     

Cross- vs. within-racial judgments of attractiveness

Subjects from two pairs of ethnic groups (Chinese and White in Experiment 1, Black and White in Experiment 2) judged the attractiveness of faces in yearbook pictures of persons that belonged to their own or to the other ethnic group. This was to see whether: (1) a given group would perceive more variation in the attractiveness of faces belonging to its own vs. the other ethnic group, as suggested by the cross-racial literature, for example, Malpass and Kravitz (1969), and (2) the two groups would use the same or different rules to define attractiveness. There were essentially no differences in perceived variation for cross- vs. within-racial judgments, but there were differences in the criteria used to define attractiveness. As expected, Black and White aesthetic criteria were more like one another than were Chinese and White criteria. Discussion centered around reconciling these findings with the recognition literature.     

The response-cued completion hypothesis and the nature of residual cost in regular switch

Three experiments are presented that compare the residual cost found when shifting from one task to another under different extra-response conditions, to test whether the response is the main factor to complete mental set reconfiguration. We investigated whether residual costs can be eliminated if participants carry out a response prior to completing switch trials. In all experiments, participants were required to press an extra key during the inter-trial interval (ITI) to proceed. In experiment 1, this extra response consisted of pressing the space bar. In experiment 2, the response consisted of pressing one of the two possible keys that belonged to the alternating tasks response set. In experiment 3, the interpolated response involved pressing one of the two possible keys, not belonging to the response set of the alternating tasks. We found no residual cost in the second or the third experiments. To explain the nature of residual cost we discuss the data in the context of a response cued completion hypothesis.     

Characters and their perspectives in narratives describing spatial environments

Summary This paper explores how people represent spatial information involving two perspectives associated with characters who share the same environment. Subjects first learned a narrative that described a scene with eight landmarks surrounding two characters who had the same or different perspective. Afterwards, subjects were given blocks of three-sentence items to be read at their own pace. The first two sentences guided the reader's attention to one character, while the third sentence described a spatial relation between a character and a landmark; subjects had to verify whether the relation was true or false. The results showed that it took longer to verify sentences after learning two-perspective narratives than it did with those of one perspective, and after reading items involving two characters rather than one. Both effects were significant and independent. To explain the perspective effect, it is proposed that subjects build a single perspective-free mental model that is instantiated as a particular perspective when necessary. The character effect has to do with modeling the characters' nonspatial traits. Finally, spatial skills were a predictor of subjects' performance, indicating individual differences in modeling efficiency.     

Decision strategies and visual-field asymmetries in same-different judgments of word meaning

The accuracy with which observers judged whether two words belonged to the same semantic category was determined from a detection-theoretic analysis ofsame-different judgments. In Experiment 1, one word was presented centrally and the other word in either the left visual field (LVF) or the right visual field (RVF); in Experiment 2, both words were presented to either the LVF or the RVF. In order to obtain receiver-operating characteristics (ROCs) of performance, observers were asked to rate their confidence that the two words belonged to the same semantic category. Two models of the decision strategy were fitted to the obtained characteristics: a differencing model, in which the decision variable was the difference between the two observations; and an optimal model, in which each observation was judged in relation to a criterion. In both experiments, the optimal model provided a better fit than the differencing model to the obtained characteristics. Maximum-likelihood estimates of both the criterion-free parameter,d′, and the area under the operating characteristic,p(A), were greater for words presented in the RVF than for those presented in the LVF.     

重复知盲:刺激呈现时间及作业对反应时的影响

本研究用汉字材料及反应时的数据来探讨重复知盲现象及有关机制。在实验一中,被试必须判断快速连续呈现的两个字究竟是否包含两个或是只有一个动物字。结果显示在７０毫秒时,有重复知盲现象（重复动物字组比非重复动物字组的反应时为长）;在１００毫秒时则无;另外,在２００毫秒时则有重复启动现象产生（重复动物字组比非重复动物字组的反应时为短）。实验二采用同样的材料及呈现方法,但被试只需要判断以７０毫秒呈现之实验材料中的第二个字是否动物字。结果发现类似重复启动的现象,这些结果显示,呈现时间与作业是决定重复刺激究竟造成知盲或启动效应的重要因素。本文另外还讨论本研究的方法与结果对了解重复刺激心理加工的可能贡献。     

错误再认:意识、注意和刺激特性

该研究基于错误再认现象,确立了意识知觉和无意识知觉在行为结果上的质的差异。在决定一个刺激是被有意识知觉还是无意识知觉时,刺激特性和注意之间存在着相互补偿的作用。实验一表明,当一个刺激短暂呈现而被无意识知觉的时候,增强刺激特性或提高注意水平都能使它的知觉变为有意识的;相对应地,实验二表明,一个处于分散注意条件下被无意识知觉的刺激,也可以通过使注意集中或增强刺激特性而使它的知觉变为有意识的。该研究对意识、注意和刺激特性三者间的关系进行了讨论。     

When two memories can and cannot be retrieved concurrently

We examined whether two memories can be retrieved concurrently from long-term memory. In Experiment 1, the subjects recalled words, either from two categories—alternating between the two—or from just one category. In Experiment 2, the subjects recalled two words belonging to either the same category or different categories, and the category prompts for these two responses appeared either simultaneously or successively. The results of both studies are consistent with the view that two items from different categories must be retrieved serially, whereas two items from the same category can be retrieved in parallel.     

The Role of Co-Occurrence Statistics in Developing Semantic Knowledge

The organization of our knowledge about the world into an interconnected network of concepts linked by relations profoundly impacts many facets of cognition, including attention, memory retrieval, reasoning, and learning. It is therefore crucial to understand how organized semantic representations are acquired. The present experiment investigated the contributions of readily observable environmental statistical regularities to semantic organization in childhood. Specifically, we investigated whether co-occurrence regularities with which entities or their labels more reliably occur together than with others (a) contribute to relations between concepts independently and (b) contribute to relations between concepts belonging to the same taxonomic category. Using child-directed speech corpora to estimate reliable co-occurrences between labels for familiar items, we constructed triads consisting of a target, a related distractor, and an unrelated distractor in which targets and related distractors consistently co-occurred (e.g., sock-foot), belonged to the same taxonomic category (e.g., sock-coat), or both (e.g., sock-shoe). We used an implicit, eye-gaze measure of relations between concepts based on the degree to which children (N = 72, age 4–7 years) looked at related versus unrelated distractors when asked to look for a target. The results indicated that co-occurrence both independently contributes to relations between concepts and contributes to relations between concepts belonging to the same taxonomic category. These findings suggest that sensitivity to the regularity with which different entities co-occur in children's environments shapes the organization of semantic knowledge during development. Implications for theoretical accounts and empirical investigations of semantic organization are discussed.     

The discrimination of cat odours by humans

We explored the ability of humans to identify individual cats by smell. Twenty-five cat owners were required to indicate which of two odours (one belonging to their own cat and one belonging to an unfamiliar cat) smelt the strongest, most pleasant, and which belonged to their own cat. Only thirteen (52%) of the participants were able to recognise the odour of their own cat.     

汉字触觉辨认与触觉双指模式

大量的以往研究涉及到字词识别 ,其中又有相当一部分是对字词或字母的触觉辨认研究 ,但未见汉字模式的触觉辨认研究。为了探讨汉字模式与英文字母或词模式触觉辨认的异同 ,我们先做简单汉字的视触匹配实验以确定此类实验是否可行。把 10个高频且笔画少的汉字在 6× 2 4的触觉振动仪上转换成振动的触觉模式 ,由于汉字比以往触觉模式辨认实验中所用的单指振动模式要复杂 ,所以我们不得不把汉字转换成双指模式 ,即用了两片振动显示仪来呈现一个模式 ,被试用双指接触振动片。汉语母语被试与从没学过汉字的英语母语被试各 10名对这些汉字触觉模式作了触觉与视觉模式匹配实验 ,结果表明两类被试的匹配成绩都很低而且无显著差异 ,结果可能是由于双指模式所致 ,从而不能完全说明汉字模式太难不适合触觉辨认 ,于是我们用单指模式的通常结构构建双指模式 ,使单双指模式的复杂度差异只表现在量上 ,检验了单双指模式的辨认效果 ,结果表明双指模式辨认成绩虽比单指辨认差但辨认中的认知特征如干扰中的反应竞争与知觉竞争效应相同。