Behavioral and pharmacological variables affecting risky choice in rats.

The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.     

The recognition potential: An ERP index of lexical access

Recognition potential (RP) is a brain electrical response that appears when a subject views recognizable images of words. However, it has yet to be determined whether the processes reflected by RP are related to orthographic or to semantic analysis. This study aimed to resolve this question by studying the RP evoked by orthographically correct stimuli that were devoid of meaning. Results showed RP not only to this type of stimuli, but also to others achieving lower levels in the reading process. Strikingly, however, the RP amplitude significantly differed in parallel with the levels of the reading processes attained by the stimuli, the amplitude of the RP progressively increasing as the level approached the semantic one, which showed the highest amplitude. These results not only confirm the replicability of RP, but also its promise of potential usefulness in the study and assessment of language perception.     

儿童对抽象画情绪寓意理解的发展及文化因素的影响

本实验旨在探索儿童对抽象图画情绪寓意敏感性的发展规律以及文化因素的影响。被试年龄跨度从 5岁至高中学生。根据被试利用形态、主题、情绪等图片特性作为识辨依据的特点来发现规律。儿童对抽象图画寓意敏感性的发展与表征水平相关。年幼儿童只能利用颜色或图形等单一信息维量进行判断 ,年长儿童及中学生可以综合利用形态、主题、情绪等多个维量判断。在寓意明确的图片识辨中 ,儿童对积极寓意的识辨成绩较优。在双关寓意的图片识辨中 ,儿童组倾向于选择具有积极寓意的线索 ,而中学生组会受到识辨经验的影响。文化与教育方式影响儿童对抽象图画情绪寓意的理解。中国幼教方式有助于儿童对图画认知与情绪成分的识辨。     

Recognition Memory for Faces: Reliability and Validity of the Warrington Recognition Memory Test (RMT) in a Neurological Sample

In response to critiques regarding the psychometric limitations of the Warrington Recognition Memory Test for faces (RMT-F), the current study was conducted to examine the test-retest reliability and validity of the measure in a neurological sample. Forty adult outpatients, ages 35–81, were administered the RMT-F as part of their diagnostic exam. A second evaluation was conducted after an average interval of 7 months (range = 2–20 months). Results yielded a Pearson reliability coefficient of 0.81 (p < .001), indicating a clinically satisfactory index of stability. Correlations with other measures were conducted to examine convergent and divergent validity. Results indicate that the facial component of the RMT has adequate reliability for patients with established neurological disease, shows moderate correlations with other measures of complex visuospatial function, and shows no significant correlation with measures of verbal reasoning, visual problem-solving, or verbal fluency. These findings provide additional support for the clinical efficacy of this instrument for use in a diverse neurological patient sample.     

Is the inversion effect in rhesus monkeys face-specific?

This study investigated the face inversion effect in rhesus monkeys (Macaca mulatta). Face stimuli consisted of ten black-and-white examples of unfamiliar rhesus monkey faces, brown capuchin faces, and human faces. Two non-face categories included ten examples of automobiles and abstract shapes. All stimuli were presented in a sequential matching-to-sample format using an automated joystick-testing paradigm. Subjects performed significantly better on upright than on inverted presentations of automobiles, rhesus monkey and capuchin faces, but not human faces or abstract shapes. These results are inconsistent with data from humans and chimpanzees that show the inversion effect only for categories of stimuli for which subjects have developed expertise. The inversion effect in rhesus monkeys does not appear to be face-specific, and should therefore not be used as a marker of specialized face processing in this species. Received: 18 November 1998 / Accepted after revision: 9 May 1999     

Innate versus learned recognition of conspecifics in great spotted cuckoos Clamator glandarius

When birds raised by another species become adults, they (if they are non-brood-parasitic species) usually attempt to mate with birds of their foster species rather than with birds of their own species, a phenomenon called sexual imprinting. Avian brood parasites lay their eggs in nests of other species (the hosts) that rear the young, but the problem of sexual imprinting among brood parasites has generally been neglected, and brood parasites have been considered as an exception among birds. Here, we show, with data from field observations and field experiments, firstly, that adult great spotted cuckoos Clamator glandarius sometimes maintain contact with both older nestling and fledgling cuckoos. Adult cuckoos visited parasitized nests during the last days of the nestling period (5 observations) and, when parasitic chicks left the nest, adult cuckoos maintained contact with the young (14 observations). Adults and fledgling cuckoos communicated vocally (5 observations), and an adult great spotted cuckoo even fed a parasite fledgling in two cases. Secondly, when experimentally cross-fostered in nests of magpie Pica pica hosts outside the parasite breeding range (thus avoiding visual and acoustic communication with adult cuckoos), young cuckoos did not learn to recognize their own species when only one cuckoo chick was introduced per nest, but they learnt to recognize conspecifics when two cuckoos were reared together. This means that young great spotted cuckoos apparently must learn to recognize conspecifics, that is, recognition is not innate. Social interactions between adult brood parasites and young have also been reported in other brood parasites; thus, brood parasites are probably not an exception to the general phenomenon of imprinting, and young brood parasites may need to be imprinted on conspecifics, although more studies on other brood parasite species are needed to confirm this. Received: 7 January 1999 / Accepted after revision: 27 February 1999     

汉字词识别过程的形,音,义编码作用的研究

本文通过两个实验,采用汉字词形、音、义特征匹配任务,探讨了影响汉字词的形、音、义编码与提取方式的有关因素。实验一发现在速示条件下,对汉字词再认的成绩并不受字词的使用度的影响,反应时无明显变化,而主要受编码加工的深度影响。在形、音、义特征加工中,对音码的加工时间最长,再认的正确率最低;义码的加工时间较短,再认正确率最高;形码的反应时及再认成绩介于音码与义码之间。实验二在非速示条件下也获得了相同的结果。研究结果表明,在汉字词的形、音、义特征中,存在着编码加工深度的差异。     

汉字识别中的部件加工：错觉性结合实验的证据

本研究用“错觉性结合”的实验范式探讨汉字识别中的部件加工。被试对两个刺激字之后出现的目标字进行再认。结果发现在速示条件下,目标字部件与刺激字的部件相同时（如目标字为“她”,而刺激字为“姓”及“地”）,被试常把目标字误认为刺激字。这种错误再认率随字频及部件频率的升高而降低。此外,刺激字的排列方式不同于字的结构方式时,字频及部件频率的效应减弱。上述结果不但表明整字频率、字的空间组织因素影响汉字识别,更显示部件是汉字认知过程的一个重要加工层次。     

The influence of adults' actions on children's inferences about word meanings

This article first establishes the effect of adults' actions on children's inferences about the shape and material of solid objects, based on data from Japanese 2-, 4-, and 6-year-olds. Japanese 2-year-olds are already sensitive to adults' actions in making inferences, and children become more adept at this as they become older. The invariance of the phenomenon of the effect of actions is then discussed in terms of three of its aspects: across age groups, across languages (the universality of the effect), and across tasks in lexical development. It is suggested that while specific linguistic characteristics (e.g., the means of individuation of entities), and complexity of object shape probably influence the effect of actions, action effects may have a potentially invariant/universal aspect.     

Infants’ responses to objects representing levels of word knowledge and categorical information

The effects of differing levels of word knowledge on infants’ sequential touching behaviors were investigated in two studies. In both, parent report was used to assess three levels of word knowledge: known, frontier, and unknown. In the first study, 14-month-old infants sequentially touched objects consistent with parents’ reports of their word knowledge. In the second study, 20-month-old infants sequentially touched objects by both conceptual category and reported level of word knowledge. It appears that even infants, like adults, can make distinctions among objects on the basis of their knowledge about the objects’ labels.