Measuring the role of conditioning and stimulus generalisation in common fears and worries

Common and persistent fears may emerge through learning mechanisms such as fear conditioning and generalisation. Although there have been extensive studies of these learning processes in healthy but also psychiatric samples, many of the tasks used to produce conditioning and assess generalisation either use painful and aversive stimuli as the unconditioned stimuli (UCS), or suffer from poor belongingness between the conditioned stimuli and the UCS. Here, we present novel data from a paradigm designed to examine fear conditioning and generalisation in healthy individuals. Two female faces served as conditioned threat cue (CS+) and conditioned safety cue (CS?) respectively. The CS+ was paired repeatedly with a fearful, screaming face (unconditioned stimulus). Generalisation included intermediate faces which varied in their similarity to the CS+ and CS?. We measured eyeblink startle reflex and self-reported ratings. Acquired fear of the CS+ generalised to intermediate stimuli in proportion to their perceptual similarity to the CS+. Our findings demonstrate how fears of new individuals may develop based on resemblance to others with whom an individual has had negative experiences. The paradigm offers new opportunities for probing the role of generalisation in the emergence of common and persistent fears.     

Learning Phonemes With a Proto‐Lexicon

Before the end of the first year of life, infants begin to lose the ability to perceive distinctions between sounds that are not phonemic in their native language. It is typically assumed that this developmental change reflects the construction of language‐specific phoneme categories, but how these categories are learned largely remains a mystery. Peperkamp, Le Calvez, Nadal, and Dupoux (2006) present an algorithm that can discover phonemes using the distributions of allophones as well as the phonetic properties of the allophones and their contexts. We show that a third type of information source, the occurrence of pairs of minimally differing word forms in speech heard by the infant, is also useful for learning phonemic categories and is in fact more reliable than purely distributional information in data containing a large number of allophones. In our model, learners build an approximation of the lexicon consisting of the high‐frequency n‐grams present in their speech input, allowing them to take advantage of top‐down lexical information without needing to learn words. This may explain how infants have already begun to exhibit sensitivity to phonemic categories before they have a large receptive lexicon.     

Children's strategic compensation for size underconstancy: Dependence on distance and relation to reasoning ability

When asked to judge the size of a distant object, older children are more likely than younger ones to report deliberately inflating their judgements to compensate for size underconstancy (Granrud, in press). The current investigation examined whether use of this strategy depends on object distance and whether it is related to individual differences in reasoning, knowledge about size perception, or cognitive style. In two studies, children in Grades 1–3 estimated the size of a distant (61 m away) and near (6.1 m away) disc. In each, half of the children reported inflating their judgement of the distant disc to compensate for a tendency to underestimate its size, but only a few reported using this strategy for the near disc. Self-reported strategy users tended to either judge the distant disc accurately or to overestimate its size, whereas the other children tended to underestimate its size. Strategy reporters obtained higher scores on a test of verbal reasoning, but did not differ from the other children in reflectivity-impulsivity. In Study 1, strategy reporters also showed a better understanding of how distance affects the apparent size of objects in photographs. This understanding was strongly related to verbal reasoning ability. In Study 2, visuospatial reasoning ability was also found to predict who would report strategy use, and this predictive relation was independent of verbal reasoning ability.     

Bimanual Training Reduces Spatial Interference

The authors investigated whether training can reduce bimanual directional interference by using a star-line drawing paradigm, Participants (N = 30) were required to perform rhythmical arm movements with identical temporal but differing directional demands. Moreover, the effectiveness of part-task training in which each movement was practiced in isolation was compared with that of whole-task training in which only combined movements were performed. Findings revealed that bimanual training substantially reduced spatial interference, but unimanual training did not. The authors therefore concluded that the spatial coupling of the limbs is not implemented in a rigid way; instead, the underlying neural correlate can undergo plastic changes induced by training. Moreover, the practical implication that emerged from the present study is that athletic, musical, or ergonomic skills that require a high degree of interlimb coordination are best served by whole-task practice.     

The Need for Power and Fear of Assertiveness in English-Speaking South African Female Graduates

The present study demonstrated that Winter's (1973) power arousal procedure and scoring system for the need for power, which were developed in the United States, are valid for English-speaking South African female graduates. Subjects in whom the need for power had been aroused by a prerecorded inspirational speech (n = 20) had significantly higher n Power scores than matched nonaroused subjects (n = 20), T ²(8, 31) = 56.17, p ≤ .01. Further, it was argued that the fear of assertiveness is a component of the need for power, and a scoring system for measuring this motive was suggested. Fear of assertiveness was shown to correlate significantly with various behavioral and dispositional measures of assertiveness, relating especially to a dependency pattern of behavior.     

Visual and Proprioceptive Determinants of Space Perception and Movement

The present study determined the relationship between perception of the upright in 2-dimensional space and movement accuracy. 161 female Ss were administered the Rod and Frame Test, and 30 Ss, whose scores indicated the greatest and least error in perceptual differentiation, were assigned to 2 experimental groups and measured on accuracy of postural pursuit tracking. The effects of direction of movement and visual field conditions on accuracy of performance were determined by a coordinate postural platform and hybrid computer methods. A direct relationship existed between perception of the vertical in space and accuracy of motor responses and that perceptual integration was affected by the direction of movement and the presence of a stable visual field.     

Relative Phase Alterations during Bimanual Skill Acquisition

The purposes of the research reported here were (a) to examine changes in relative phase during the acquisition of a new coordination pattern and (b) to determine the effect of learning this pattern on the ability to perform other coordination patterns. Ten subjects practiced an upper limb coordination task that required a 90° phase offset and different amplitudes for each arm. A gross approximation of the mean relative phase for the intended coordination pattern occurred quickly, but the attainment of stability occurred much more gradually. These results were accompanied by changes in pattern stability across practice and on various transfer tests. Learning of the new coordination pattern also affected the stability of the anti-phase mode, but this effect was only temporary.     

Two-year-olds can begin to acquire verb meanings in socially impoverished contexts

By two years of age, toddlers are adept at recruiting social, observational, and linguistic cues to discover the meanings of words. Here, we ask how they fare in impoverished contexts in which linguistic cues are provided, but no social or visual information is available. Novel verbs are presented in a stream of syntactically informative sentences, but the sentences are not embedded in a social context, and no visual access to the verb’s referent is provided until the test phase. The results provide insight into how toddlers may benefit from overhearing contexts in which they are not directly attending to the ambient speech, and in which no conversational context, visual referent, or child-directed conversation is available.     

听觉条件下词汇获得年龄效应产生机制的初探

通过三个实验考察听觉词汇的获得年龄效应。实验1采用基于语音的词汇判断任务,在错误率上存在词汇获得年龄效应,即早期习得词汇的正确率高于晚期习得词汇;实验2、3分别采用基于字形和语义的词汇判断任务,在反应时上存在词汇获得年龄效应,即早期习得词汇的反应快于晚期习得词汇。结果支持任意映射假说的观点：⒈词汇获得年龄效应产生于音、形、义加工的多个方面;⒉映射程度高低是决定词汇获得年龄效应大小的重要因素。