bluuebunny/crossref_metadata_2025 huggingface dataset:
Cognitive profiles of groups of poor readers and dyslexic children on the British Ability Scales
Authors: Tyler Stephen , Elliott Colin D.
Published: April 2011

Two samples of children with reading difficulties − 145 poor readers and 121 dyslexic children ‐ were tested on the British Ability Scales (BAS). The poor readers were classified, using Rutter & Yule's (1975) criteria, into children with specific reading retardation and general reading backwardness. These children's profiles of scores on the BAS were also entered into a cluster analysis which provided some confirmation of the validity of the Rutter & Yule classification.

The BAS scores of the dyslexic children were also entered into a cluster analysis. Three groups were identified: 30 with mixed visuo‐spatial and linguistic processing problems, 52 with sequential processing problems, and 39 with problems in the holistic retrieval of information. It was concluded that the data lend support to the view that children with specific reading retardation, and dyslexic children in particular, are not homogeneous in their cognitive profiles.

Finally, each group identified above was analysed for fit to the Lawson & Inglis (1985) principal components model of learning disability. The fit to the model for most groups was poor. It was concluded that a model which implicates left hemisphere aetiology for all LD children is inadequate. Some benefit, however, is likely to accrue from the more rigorous definition of specific subtypes, and in this endeavour the BAS appear to offer a useful advance in such assessment and identification.
The effect of spaced practice on explicit and implicit memory
Authors: Perruchet Pierre
Published: April 2011

The spaced‐practice effect refers to the strong and pervasive positive influence on long‐term explicit memory which results from interposing at least one other item between the repetitions of any to‐be‐remembered item in a list‐learning paradigm. Limited prior empirical evidence suggests that spaced practice could also have a similar positive effect on implicit memory performances, as revealed through a tachistoscopic identification task.

Four experiments involving another implicit memory task, namely a perceptual clarification procedure, were conducted to test for the effect of spaced practice with greater methodological control than previously used. Low‐frequency words were displayed to subjects under a variety of conditions including incidental (Expts 1 and 2) and intentional (Expts 3 and 4) learning instructions. Although spacing regulated to a large extent the performances in subsequent free recall (Expt 2) or recognition (Expts 1, 3, 4) control tasks, the advantage of spaced over massed items in the perceptual clarification procedure was always small in magnitude, and only reached significance in the last experiment. Overall analysis of the data shows with a reasonably high degree of certitude that spaced practice exerts a real but probably slight and fluctuating effect upon implicit memory performance.
Demographic and psychological determinants of homesickness and confiding among students
Authors: Brewin Chris R. , Furnham Adrian , Howes Mark
Published: April 2011

This study investigated some of the determinants of homesickness and reactions to homesickness in two samples of first‐year English psychology students who had left home for the first time. Homesickness was found to be a reasonably common but short‐lived phenomenon, and was predicted longitudinally by greater self‐reported dependency on other people and by higher estimates of the frequency of homesickness among students in general. Although homesickness was equally common in men and women, women were much more likely to discuss their feelings with others and to respond by being more affiliative. Greater anxiety and depression about homesickness were also associated with more confiding behaviour. There was a suggestion that homesick male students were more likely to seek out others, the more common they perceived homesickness to be.
Abstract letter identities and developmental dyslexia
Authors: Bigsby Pamela
Published: April 2011

Four experiments, first used by Bigsby (1988 a), were presented to three groups of competent readers of varying reading ages and to nine developmentally dyslexic children. As in the initial study, competent reader data were analysed using group statistical analysis techniques together with some discussion of individual experimental effects and error levels. Competent reader data were also analysed, as were data from the dyslexic subjects, at a cognitive functional level and individual processing descriptions were obtained.

Results from the group analysis confirmed earlier findings that nominal matches engage an abstract letter identity (ALI) code which has a similar capacity to the visual code and that, when the ALI code of a reversible letter (b, d, p, q) is accessed, an extra processing step is probably involved. Individual processing descriptions revealed that several of the dyslexic subjects displayed major impairments in ALI coding while some of the competent readers showed mild inefficiencies. A developmental trend towards greater processing efficiency was noted, using both methods of analysis, for the competent reader sample.

It is concluded that results are consistent with those models of word recognition which depict ALI coding as a necessary prerequisite to word recognition.
Transitive inferences by young children about spatial position
Authors: Pears Rosalind , Bryant Peter
Published: April 2011

This study investigates the ability of young children to make transitive inferences about spatial position. Our aim was to discover whether they could work out that A must be in a higher position than C, if A is above B and B above C. Our technique was to show children three or more ‘premise’ towers, each consisting of two bricks of different colours and to ask the children to build a larger tower which preserved the spatial relationships of the colours in the premise towers. So, if the child saw three premise towers, and in one red was above blue, in another blue above green and in the third green above yellow, s/he would have to build a red above blue above green above yellow tower. Before the child built the larger tower, we posed inferential questions about the relation of bricks in that tower: e.g. which would be in the higher position, red or green? We gave problems with three, four and five premise towers to 58 four‐year‐old children. They were able to make transitive inferences about spatial position with considerable success.
Investigating personal constructs of emotions
Authors: Parkinson Brian , Lea Martin
Published: April 2011

Forty‐two first‐year psychology students took part in an exploratory study of conceptions of emotions using Kelly's (1955) Repertory Grid technique. Each participant generated eight different personal constructs for comparing and contrasting eight different emotional states, then rated these emotions on the basis of their own constructs. Analysis of the group data revealed five significant principal components. The first four of these components related to evaluation (positive vs. negative), direction (inner‐directed vs. outer‐directed), duration (long‐term vs. short‐term), and causation (internal vs. external cause). The fifth component was not so readily interpretable. The internal complexity of the components suggested that participants' implicit theories of emotions are relatively well articulated and do not depend on simple unitary dimensions of comparison. Potential advantages of the repertory grid technique in this kind of research are considered.
Typicality in categorization, recognition and identification: Evidence from face recognition
Authors: Valentine Tim , Ferrara André
Published: April 2011

The proponents of exemplar models of categorization and memory have claimed that recognition judgements are based on familiarity computed by summing the similarity between a probe and all exemplars in memory. A probe which is highly similar to many previously seen exemplars should be recognized more accurately or faster than a more dissimilar probe. The ‘summed‐similarity rule’ has been supported in a number of experiments on recognition of relatively unfamiliar and artificial stimuli. However, evidence from face recognition clearly contradicts the rule. Distinctive or unusual faces are recognized more accurately than typical faces. It is proposed that this contradiction can be resolved if tasks using photographs of faces as stimuli which have been termed ‘recognition’ tasks are interpreted as ‘identification’ tasks. However, if this interpretation is made, an exemplar model is not the only class of models which can account for the effects of distinctiveness in face ‘classification’ and ‘identification’ tasks. Three simulations are reported which show that parallel distributed processing models can also account for the data from face‐processing tasks. Two simulations are based on a single‐layer auto‐associative network. The final simulation is based on a multi‐layer network using backward error propagation.
The psychological impact of unemployment and unsatisfactory employment in young men and women: Longitudinal and cross‐sectional data
Authors: Winefield Anthony H. , Tiggemann Marika , Winefield Helen R.
Published: April 2011

Data are presented from the seventh wave of a longitudinal study of school‐leavers that commenced in 1980. Four groups were compared: satisfied employed, dissatisfied employed, unemployed and full‐time tertiary students. The groups differed initially with respect to only one background variable, teacher‐rated academic potential, and did not differ on any of the psychological measures of well‐being. In general, the unemployed and dissatisfied employed groups displayed poorer psychological well‐being than the satisfied employed and student groups on a range of measures. The longitudinal data suggested that this was because the two disadvantaged groups showed smaller improvements than the others, rather than any deterioration. The results also suggested that for the males unemployment was worse than unsatisfactory employment, but that for the females unsatisfactory employment was worse than unemployment.
The effect of orthography on the acquisition of literacy skills
Authors: Thorstad G.
Published: April 2011

The effect of the regularity of orthography on the acquisition of literacy skills was studied by comparing the reading and spelling of 70 Italian children aged 6–11 years with that of 90 English children learning traditional orthography (t.o.) and 33 children aged 6–7 years learning the initial teaching alphabet (i.t.a.), using an Italian passage for adults which was also translated into English. The Italian children learned to read at an earlier age than the English t.o. children, but not than the English i.t.a. children. The English t.o. and i.t.a. children could read more words than they could spell, whereas the Italian children could spell most of the words they could read and even some they could not read.

The English children read fast and inaccurately, whereas the Italian children read slowly and accurately using a systematic, phonological strategy until 10 years, when they read fast and accurately. All the children used a phonological strategy in spelling, but only the Italians were mostly successful. Thus the results suggest that, if the orthography is predictable and invariant, the children use a systematic, phonological strategy and learn to read and spell more quickly and accurately.
The anthropomorphic machine: Causal order in nature and the world view of common sense
Authors: White Peter A.
Published: April 2011

The first two studies investigate naïve ideas about the causal order in natural processes, using a cause‐effect pair construction method. Results show that people are not naïve systems theorists: they produce fewer feedback loops than would be expected by chance and treat nature as an Aristotelian one‐way causal hierarchy in which causal chains are overwhelmingly linear and causal influence is disseminated down from the top level of the system in an anthropomorphic manner involving the action of the causal powers of things. The action of the top level is treated in a manner analogous to the exercise of free will. In the third study, people endorsed a view of the world in general as a large and complex machine that never runs down, but which is endowed with the Aristotelian properties of purposiveness, direction towards mature forms, constructiveness, and natural justice.
Police—Schools Liaison and young people's image of the police: An intervention evaluation
Authors: Hopkins Nick , Hewstone Miles , Hantzi Alexandra
Published: April 2011

This paper evaluates the impact of Police‐Schools Liaison on young people's views and attitudes about the police and offending. It reports the first, large‐scale, independent evaluation of this social intervention. The evaluation (based on 1245 secondary‐school pupils) compares views of the police in schools with (target) and without (control) a full‐time Schools Liaison Officer (SLO). Although attitudes to the police are marginally positive, they become less so over one year. There is no evidence that Schools Liaison input into the target schools slows or halts this decline, or that it affects perceptions of the seriousness of offences, and the likelihood of identification associated with crime. This weak impact is, at least in part, attributable to the low reported rates of direct contact, and the judged atypicality of the SLO. Target‐school pupils judged their SLO positively, but as distinct from the ‘police in general’. Their view of the SLO had a direct impact on their liking of the police in general, but there was no effect for contact. We conclude that Police‐Schools Liaison has only limited positive effects, as predicted from critiques of the traditional ‘contact hypothesis’.
Expedition stress and personality change
Authors: Watts Fraser N. , Webster Shernaaz M. , Morley Colin J. , Cohen John
Published: April 2011

There have been few attempts to investigate the widespread assumption that short‐term challenges can have beneficial effects on personality. An expedition to India organized by the British Schools Exploring Society provided such an opportunity. The Gordon Personal Profile Inventory showed that the expedition was associated with increased ascendancy, emotional stability, sociability and responsibility, and decreased cautiousness. Women tended to benefit more than men. The results suggest that the expedition was associated with positive personality changes, though other explanations of the findings cannot be ruled out.
Behavioural problems associated with the chronic fatigue syndrome
Authors: Smith Andrew P. , Behan Peter O. , Bell Wendy , Millar Keith , Bakheit Majid
Published: April 2011

Disturbances of memory, concentration and motor function are often reported by patients with the chronic fatigue syndrome (CFS). The present study objectively evaluated these behavioural problems using a computerized test battery measuring memory, attention and motor skills. Fifty‐seven CFS patients were compared with 19 matched controls and all subjects completed the performance test battery and filled in questionnaires measuring psychopathology and mood. The patients reported significantly higher levels of depression, anxiety, physical symptoms and cognitive failures than the controls. Similarly, they reported more negative affect at the time of testing. The patients were slower on psychomotor tasks, showed increased visual sensitivity and impaired attention. Digit span and free recall were not impaired but retrieval from semantic memory and logical reasoning were slower. None of the performance differences between patients and controls could be attributed to differences in psychopathology. These results agree with recent findings from other laboratories, and it is now time to consider the nature of the neurological dysfunction underlying these effects.
The handedness of Kerrs and Carrs
Authors: Shaw Duncan , McManus I. C.
Published: April 2011

The surnames Kerr and Carr have been claimed, on the basis of folkloric and etymological evidence, to be associated with an increased incidence of left‐handedness. In 1974 a survey by the Royal College of General Practitioners suggested that the incidence of left‐handedness was nearly three times as high in Kerr/Carr families as in controls. That survey was however potentially flawed by response biases. In the present study, which used better controls, no evidence was found for an increased incidence of left‐handedness in Kerrs and Carrs.
Grapheme–phoneme correspondence in dyslexic and matched control readers
Authors: Fox Elaine
Published: April 2011

Snowling (1980) reported that dyslexic children appear to have specific deficits in grapheme–phoneme conversion skills. Using a similar methodology, the present study compared the ability of dyslexic and control readers to make phoneme discriminations between the beginnings and ends of words. Recognition of word pairs as same or different were presented in four conditions: visual presentation–visual recognition (V–V), auditory–auditory (A–A), visual–auditory (V–A) and auditory–visual (A–V). It was found that dyslexic readers had particular difficulty with the mixed‐mode conditions (V–A, A–V) which required grapheme–phoneme conversion. Furthermore, dyslexic readers were particularly error‐prone in these conditions if words differed on their end‐sound rather than their beginning sound.
Ranking or rating? Some data and their implications for the measurement of evaluative response
Authors: Russell P. A. , Gray C. D.
Published: April 2011

Two groups of 80 subjects rated 15 paintings on a five‐point pleasingness scale in accordance with a ‘relative’ instruction, requiring them to compare the paintings with one another, or an ‘absolute’ instruction, requiring them to compare the paintings with other, familiar ‘anchor’ paintings. Each subject also ranked the paintings on pleasingness, either before or after doing the ratings. Within‐subject correlations between ranks and ratings revealed that, for all but a small minority of subjects, there was a moderate to high level of correspondence between the two measures. There was a tendency for those subjects who had shown good correspondence between their ranks and their ratings to show a greater spread in their ratings. The relative instruction also produced a greater spread in subjects' ratings compared with the ratings obtained under the absolute instruction. The means of the ranks and the ratings that the subjects assigned to the individual paintings were highly correlated in both groups. The results are discussed in terms of the respective merits of ranking and rating procedures, and it is concluded that, where practical and statistical considerations permit, and where the items are highly discriminable, a ranking procedure has advantages. Where ranking is precluded, however, a rating procedure with ‘relative’ instructions offers some of the same desirable characteristics.
Personality and quality of marriage
Authors: Russell Robin J. H. , Wells Pamela A.
Published: April 2011

The influence of personality on quality of marriage was examined using causal modelling on a sample of 94 couples who had completed a quality of marriage scale and the revised short form of the Eysenck Personality Questionnaire. Irrespective of gender, quality of marriage was found to be influenced negatively by spouse's neuroticism, but the strongest influence on the quality of marriage of each spouse was the quality of marriage of the other. Altogether, the model accounted for over 60 per cent of the variance in quality of marriage, and provided an extremely close fit to the data. Finally, it was argued that valid conclusions about marital quality can only be derived from couples rather than from married individuals.
Bereavement following death of a pet
Authors: Archer John , Winchester Gillian
Published: April 2011

A 40‐item questionnaire based on reactions following human bereavement was used to investigate the occurrence of grief following death of a pet in a sample of 88 people. Items indicating initial numbness or disbelief, preoccupation with the loss, a loss of part of themselves and being drawn towards reminders were endorsed by half to four‐fifths of the sample. About a quarter reported the urge to search, avoidance or mitigation strategies, anger, anxiety and depression. The questionnaire showed high internal reliability, and total scores were significantly positively correlated with the degree of affective attachment to the pet, the suddenness of the death and whether the respondent lived alone; but not with the type of pet, the time since it had died, and how long the owner had been with it. Factor analysis of the questionnaire revealed one main factor accounting for about a third of the variance, described as emotional distress associated with the loss; two lesser factors involved items representing personal importance of the loss and a feeling of continued attachment. Overall these findings indicate a parallel reaction to that following a human bereavement, but with a lower frequency of affective distress. Moderator variables were also comparable with those known to be important for grief following a human loss.
Interference effects of mental imagery on a motor task
Authors: Hall Craig , Bernoties Lisa , Schmidt Darlene
Published: April 2011

It can be argued that imaginary practice and physical practice are functionally similar. Evidence in support of this hypothesis comes from several experiments demonstrating that interference effects from imaginary practice in motor learning and motor memory are similar in both direction and size to those resulting from physical practice. The purpose of the present study was to provide additional support for this finding using a retroactive interference paradigm. Sixty participants were required to practise performing a simple motor task that was to be completed in a criterion time of 700 ms. They then were randomly assigned to one of six groups. These groups differed in the amount and type of interpolated practice they experienced. One physical practice group attended one session of interpolated activity involving physical practice of another motor task. The other physical practice group participated in two such sessions. One imagery group attended a single session entailing imaginary practice of the same interpolated motor task, while the other imagery group had two such sessions. A fifth group experienced a combination of physical practice and rest periods for two interpolated sessions. A control group did not experience any interpolated activity sessions. Following the interpolated activity sessions, all groups were given a retention/reacquisition test on the original motor task. Imaginary and physical practice during the interpolated activity sessions caused similar interference effects on retention/reacquisition. All groups showed greater deviation from the criterion movement time (700 ms) during the retention test than the control group, and these deviations were in the expected direction given the nature of the interpolated motor task.
Similarity of movement in recognition of self‐performed tasks and of verbal tasks
Authors: Engelkamp Johannes , Zimmer Hubert D.
Published: April 2011

Recognition performance is strongly enhanced when subjects not only verbally learned actions, but also performed the actions during learning. In the multimodal memory model, this effect is explained by assuming that learning by enactment provides subjects with motor information which helps recognition of old items. However, the same type of information should impair recognition and increase the number of false alarms when the distractors are motorically similar and subjects reprocess motor information during testing. We tested this prediction. Subjects learned actions either by verbal means or by performing the denoted actions. Recognition performance was tested in a single‐item old/new decision. The distractors were constructed by changing the objects or the verbs of the old items so that the new items were either conceptually and motorically similar or dissimilar. Half of the items were tested verbally, whereas the other half were also performed during testing. The results supported the predictions. Hit rates were higher in the enactment group than in the verbal group. Similar distractors were more often erroneously accepted as old than dissimilar items. This effect was strongest for those subjects who enacted the actions during learning and testing. In addition, it was observed that object changes were more easily detected then verb changes, which effect did not interact with any other factor.
Visuospatial working memory, movement control and executive demands
Authors: Salway Alice F. S. , Logie Robert H.
Published: April 2011

Developments in the concept of a specialist visuospatial resource in working memory owe much to a pair of tasks originally developed by Brooks (1967), involving respectively the generation and retention of a mental image of a matrix pattern and the retention of a verbal sequence. Previous literature has demonstrated that the matrix task calls on cognitive resources which are involved in both the processing of visual input and the generation of movement sequences. Using dual task methodology, the study reported here demonstrates that the matrix and verbal versions of the task do indeed rely on separate, specialized cognitive resources, one of which is also involved in generation of action. However, when the secondary task (random generation of numbers) was very demanding of general purpose cognitive resources both the matrix and verbal tasks were performed poorly, suggesting that each of these tasks draw heavily on a common, general purpose resource as well as on their respective specialist resources. It is argued that random generation offers a means to assess general purpose cognitive resources and that the cognitive processes involved in the Brooks tasks may be more complex than has been previously assumed.
More than just a game: Research developments and issues in competitive anxiety in sport
Authors: Jones Graham
Published: April 2011

This paper provides a critical overview of developments and issues in competitive anxiety research. The discussion is divided into sections dealing with general arousal‐based approaches, general anxiety‐based approaches and, finally, multidimensional anxiety‐based approaches. The major emphasis is on multidimensional anxiety‐based approaches, in which a number of factors and issues surrounding the competitive anxiety response are addressed, including: conceptual and measurement developments; antecedents of competitive anxiety; temporal patterning of the response; and frequency of competition‐related cognitive intrusions. Research which has examined the relationship between multidimensional anxiety and performance is considered in detail, including debilitative and facilitative competitive anxiety states and catastrophe models. A control model of debilitative and facilitative competitive anxiety is proposed. Finally, recommendations for future research are suggested.
Screening cervical smears
Authors: Laming Donald
Published: April 2011

A plausible explanation is offered why an experienced pathologist engaged in the screening of cervical smears should have issued a large number of false‐negative diagnoses. The explanation centres on the interactions which occur between successive judgements when a sequence of similar stimuli are inspected. Briefly, those interactions have the character of an assimilation of each judgement to its predecessor, and the resultant process is capable of ‘running away’. A procedure is suggested, involving the provision of immediate knowledge of results for a small proportion of the smears inspected, which would prevent such systematic misdiagnoses from recurring in the future.
Occupational stress among senior police officers
Authors: Brown Jennifer , Cooper Cary , Kirkcaldy Bruce
Published: April 2011

From a survey of over 500 senior UK police officers completing the occupational stress inventory, it was observed that those serving in England and Wales exhibited the highest job stress related to structure and climate, co‐worker relationships and their managerial role. There were no inter‐regional differences on the individual difference variables, Type A behaviour, locus of control, or on physical health measures. Superintendents in Scotland used coping methods least frequently including domestic/home support, time management and social support, the latter strategy being most used by Northern Ireland officers. Findings relating job stress to job satisfaction were inconsistent with other police populations. Results are discussed in the context of organizational reform in the police service.
Self‐preserving assessments of skill?
Authors: Groeger John A. , Grande Gunn E.
Published: April 2011

The studies reported in this paper had two aims: (a) to identify which psychological variables underlie people's overly positive assessments of their own ability and (b) to explore the relationship between these and actual ability. In a first study, over 300 drivers assessed their driving ability in comparison to that of a novice. A positive view of own driving ability was directly related to the amount of accident‐free and endorsement‐free driving experience a driver had had and the driver's level of Neuroticism. It was negatively related to the number of errors drivers reported in other everyday tasks. In a second study, the actual driving skills of over 100 of the original subjects were assessed by a driving instructor. It was found that self‐assessments did not relate to actual ability, but instead to the comments made by the instructor and the subject's self‐assessment as measured during the earlier study. These results are discussed in terms of a stable, but inaccurate, self‐concept which is established as experience of the domain grows in the absence of contrary evidence.
The speed–error trade‐off problem in psychometric testing
Authors: Dennis Ian , Evans Jonathan St B. T.
Published: April 2011

The standard procedure for scoring speeded psychometric tests (guessing corrected number right in fixed time) produces scores which depend both on the speed and accuracy of candidates' responding. These in turn depend both on a candidate's ability to perform the task and the compromise between speed and accuracy which is adopted. This paper uses computer simulations based on McClelland's (1979) cascade model to investigate the extent to which the scores produced reflect ability, as they purport to do, and the extent to which they are contaminated by speed‐error strategy. The standard scoring procedure is compared with some alternative methods for combining speed and accuracy. It is concluded (a) that the standard scoring procedures give scores which are strongly affected by the candidate's compromise between speed and error, (b) that alternative scoring formulae may be less affected and (c) that tests for the sensitivity of scores to speed accuracy compromise should be added to standard test development procedures.
A new approach to exploring biases in educational assessment
Authors: Dennis Ian , Newstead Stephen E. , Wright David E.
Published: April 2011

This paper presents and illustrates an approach to the study of marking biases based on multi‐sample confirmatory factor analysis. This is applied to the marks awarded by two independent markers to the final year dissertations of 197 female and 58 male psychology undergraduates. One of the two markers had supervised the work on which the dissertation was based on a one‐to‐one basis. The results suggest that about 30 per cent of the variance in the supervisor's mark is attributable to influences which are specific to the supervisor, orthogonal to the merit of the project as assessed by the two markers jointly, and general across each of the four marks awarded by the supervisor. The most plausible interpretation of these influences is that they represent a contamination of the supervisor's mark by personal knowledge of the student. These biases in the supervisor's marking were found to have more influence for male than for female students and to elevate the marks of males relative to those of females to a small but significant extent. It would be unwise to overgeneralize from these findings, but they demonstrate the potential value of this method of studying marking biases.
Emotions are social
Authors: Parkinson Brian
Published: April 2011

In this paper, I question the assumption that emotions are first and foremost individual reactions, and suggest instead that they are often best viewed as social phenomena. I show that many of the causes of emotions are interpersonally, institutionally or culturally defined; that emotions usually have consequences for other people; and that they serve interpersonal as well as cultural functions in everyday life. Furthermore, many cases of emotion are essentially communicative rather than internal and reactive phenomena. Previous research has often underestimated the importance of social factors in the causation and constitution of emotion. In conclusion, I recommend that existing cognitive and physiological approaches to emotional phenomena be supplemented or supplanted by social psychological analysis.
The conjunction fallacy: The case for the existence of competing heuristic strategies
Authors: Fisk John E. , Pidgeon Nick
Published: April 2011

A study was conducted to evaluate the effects of training on the incidence of the conjunction fallacy. One group received training in the extension rule (normative), the other training which stressed that judgments should be based on similarity or representativeness (non‐normative). Participants receiving the former made fewer errors, those receiving the latter made more errors. However, multiple regression analysis showed that under both training regimes in a majority of instances only the smaller component probability was statistically significant in determining the conjunction. A second study, omitting the training element, replicated this finding. Both studies highlight the fact that existing theories cannot account for the pattern of participants' responses under the training conditions employed. It is proposed that rather than choose between two competing strategies (Agnoli & Krantz, 1989), participants derive their estimate in two stages, first by selecting a reference point in the probability continuum, usually based on the ‘ surprise value’ of the smaller component event (Shackle, 1969) and then assigning a value to the conjunction relative to this point. During the second stage, training is hypothesized to produce its effect as participants weigh the available information deriving some compromise reflecting both normative and non‐normative tendencies.
Quantification and symmetry: Commentary on Michell, Quantitative science and the definition of measurement in psychology
Authors: Luce R. Duncan
Published: April 2011

Several of Michell's points are amplified and emphasized and the following additional point is made. Most quantitative attributes can be measured in more than one way, and there are interesting questions about how they relate. Among other things, units of measurement and symmetries of the underlying structure may or may not agree.

Because I agree with almost everything Michell says, my commentary is restricted to some amplification and to an added observation.
Handedness dependency in recall from everyday memory
Authors: Jones Gregory V. , Martin Maryanne
Published: April 2011

A number of previous studies have demonstrated systematic misremembering of the direction in which the Queen's head faces on British coins. Two experiments were carried out to investigate whether this phenomenon is affected by a person's handedness. In both experiments, right‐handed and left‐handed participants were found to differ significantly in their verbal responses, with recall performance significantly worse than chance for right‐handed but not for left‐handed participants. Experiment 2 also examined degrees of handedness, and found significant variation in recall across the handedness range. Performance in this everyday‐memory paradigm appears to be determined by both handedness and schema factors. It is proposed that although in this task the response was a verbal one, relevant motor imagery may nevertheless have been activated and led to the highly unusual observation of an effect of handedness upon cognitive performance.
Expertise in musical sight reading: A study of pianists
Authors: Waters Andrew J. , Townsend Ellen , Underwood Geoffrey
Published: April 2011

Musical sight reading on the piano represents a complex transcription task involving a series of overlapping perceptual, cognitive and motoric processes. It is suggested that skilled sight reading requires the development of efficient input skills, especially ‘pattern recognition’ skills, ‘prediction’ skills and the ability to generate and use auditory representations. The sight‐reading ability of pianists was assessed before being tested in a series of laboratory experiments assumed to involve relatively distinct processing demands. These laboratory tasks measured (i) verbal protocols as participants previewed a piece of music to be sight read; (ii) the speed of naming individual notes; (iii) recall accuracy of briefly presented chords; (iv) the time to make a same/different judgment of two repeatedly presented sequences; (v) priming effects in a chord judgment task; (vi) same/different judgments in comparing visual musical notation with an auditory sequence; and (vii) performance in a musical problem‐solving task, in which a missing bar from a phrase had to be identified. Analyses of variance conducted on individual experiments demonstrated that performance in a number, though not all, of these tasks was associated with sight‐reading skill. Correlational analyses showed that performance in the pattern‐recognition task requiring immediate recall of rapidly presented chords correlated most strongly with sight‐reading skill. Performance in the visual–auditory comparison task, a task tapping the ability to generate auditory representations, also correlated strongly. There was a weaker statistical correlation between sight‐reading skill and prime size effects in the priming task, a task thought to tap prediction ability. A multiple regression analysis in which performance on the pattern‐recognition tasks was entered first into the analysis, demonstrated that the prediction of sight‐reading skill was improved when performance on the visual–auditory matching task and the priming task were entered on the following two steps. These analyses indicate that the ability to use auditory representations and the development of prediction skills may be important over and above basic pattern‐recognition skills in musical sight reading.
Differences between implicit and explicit acquisition of a complex motor skill under pressure: An examination of some evidence
Authors: Bright J. E. H. , Freedman O.
Published: April 2011

Masters (1992) argued that an implicitly acquired motor skill is less likely to fail under pressure than an explicitly acquired skill. He demonstrated this by showing that induced anxiety led to differences in the golf putting performance of groups who had acquired the skill implicitly and explicitly. We replicated Masters' basic findings but our results suggest that the difference in performance under pressure is more readily explained in terms of differences between the learning and testing conditions. Our results are consistent with an explicit learning account of the putting task and we found no support for the claim that implicit and explicit learning of motor skills are differentially affected by anxiety.
Repetition priming for face speech images: Speech‐reading primes face identification
Authors: Campbell R. , De Haan E. H. F.
Published: April 2011

Does speech‐reading (classifying a facial image in terms of speech‐sound) proceed independently of other face‐reading skills? Repetition priming of face images was used to address this question. Earlier studies established that identity‐based decisions are sensitive to earlier exposure of images of a well‐known person, but that face‐reading tasks such as expression or age classification may not be. We extended the repetition priming paradigm to speech‐reading and in three experiments established that (a) identity decisions for personally familiar faces were sensitive to a previous image of that person's face making a speech‐sound (identity decisions were primed by speech‐reading), (b) speech‐sound matching was not faster for known faces seen earlier in a different task (speech‐reading was not primed by identification). We also found some evidence that knowledge of familiar faces could interfere with classification of face images for speech (unfamiliar faces were speech‐read faster) and that repeating a speech‐classification task could give rise to form rather than face‐based priming. These findings are discussed in relation to the separability of speech‐reading from other face processing tasks.
Axonal failure during high frequency stimulation of rat subthalamic nucleus
Authors: Zheng Fang , Lammert Katja , Nixdorf‐Bergweiler Barbara E. , Steigerwald Frank , Volkmann Jens , Alzheimer Christian
Published: April 2011

Non‐technical summary  Deep brain stimulation (DBS) refers to a neurosurgical technique where chronically implanted electrodes serve to deliver electrical impulses to highly defined brain regions in neuropsychiatric disorders including Parkinson's disease (PD), depression and obsessive–compulsive disorders. Despite its broad acceptance as a safe and effective treatment for advanced PD, DBS has remained enigmatic with respect to its underlying mechanism(s). In general terms, DBS is capable of reinstating regular electrical activity in the complex neuronal networks that exhibit aberrant firing properties in PD, but how this effect is achieved at the network and cellular level is still highly debated. Our study focuses on a crucial, but hitherto neglected, issue in this controversy, namely the propagation of impulses within and away from the site of electrical stimulation. We propose that DBS overburdens the capacity of axons to transmit signals, thereby filtering and abating the pathological activity in the brain motor loops of PD patients.
Lymphatic anatomy and biomechanics
Authors: Negrini Daniela , Moriondo Andrea
Published: April 2011

Abstract  Lymph formation is driven by hydraulic pressure gradients developing between the interstitial tissue and the lumen of initial lymphatics. While in vessels equipped with lymphatic smooth muscle cells these gradients are determined by well‐synchronized spontaneous contractions of vessel segments, initial lymphatics devoid of smooth muscles rely on tissue motion to form lymph and propel it along the network. Lymphatics supplying highly moving tissues, such as skeletal muscle, diaphragm or thoracic tissues, undergo cyclic compression and expansion of their lumen imposed by local stresses arising in the tissue as a consequence of cardiac and respiratory activities. Active muscle contraction and not passive tissue displacement is required to support an efficient lymphatic drainage, as suggested by the fact that the respiratory activity promotes lymph formation during spontaneous, but not mechanical ventilation. The mechanical properties of the lymphatic wall and of the surrounding tissue also play an important role in lymphatic function. Modelling of stress distribution in the lymphatic wall suggests that compliant vessels behave as reservoirs accommodating absorbed interstitial fluid, while lymphatics with stiffer walls, taking advantage of a more efficient transmission of tissue stresses to the lymphatic lumen, propel fluid through the lumen of the lymphatic circuit.
Design and Testing of a Micromix Combustor With Recuperative Wall Cooling for a Hydrogen Fueled μ-Scale Gas Turbine
Authors: Robinson A. E. , Funke H. H.-W. , Hendrick P. , Wagemakers R.
Published: April 2011

For more than 1 decade up to now, there is an ongoing interest in small gas turbines downsized to microscale. With their high energy density, they offer a great potential as a substitute for today’s unwieldy accumulators found in a variety of applications such as laptops, small tools, etc. But microscale gas turbines could not only be used for generating electricity, they could also produce thrust for powering small unmanned aerial vehicles or similar devices. Beneath all the great design challenges with the rotating parts of the turbomachinery at this small scale, another crucial item is in fact the combustion chamber needed for a safe and reliable operation. With the so-called regular micromix burning principle for hydrogen successfully downscaled in an initial combustion chamber prototype of 10 kW energy output, this paper describes a new design attempt aimed at the integration possibilities in a μ-scale gas turbine. For manufacturing the combustion chamber completely out of stainless steel components, a recuperative wall cooling was introduced to keep the temperatures in an acceptable range. Also a new way of an integrated ignition was developed. The detailed description of the prototype’s design is followed by an in depth report about the test results. The experimental investigations comprise a set of mass flow variations, coupled with a variation of the equivalence ratio for each mass flow at different inlet temperatures and pressures. With the data obtained by an exhaust gas analysis, a full characterization concerning combustion efficiency and stability of the prototype chamber is possible. Furthermore, the data show full compliance with the expected operating requirements of the designated μ-scale gas turbine.
Experimental Investigations of Pressure Losses on the Performance of a Micro Gas Turbine System
Authors: Zanger Jan , Widenhorn Axel , Aigner Manfred
Published: April 2011

Pressure losses between the compressor outlet and the turbine inlet are a major issue of overall efficiency and system stability for a solid oxide fuel cell/micro gas turbine (MGT) hybrid power plant system. The goal of this work is the detailed analysis of the effects of additional pressure losses on MGT performance in terms of steady-state and transient conditions. The experiments were performed using the micro gas turbine test rig at the German Aerospace Centre in Stuttgart using a butterfly control valve to apply additional pressure loss. This paper reports electric power and pressure characteristics at steady-state conditions as well as a new surge limit for this Turbec T100 micro gas turbine test rig. Furthermore, the effects of additional pressure loss on the compressor surge margin are quantified and a linear relation between the relative surge margin and additional pressure loss is shown. For transient variation of pressure loss at constant turbine speed, time delays are presented and an instability issue of the commercial gas turbine controller is discussed. Finally, bleed-air blow-off and reduction of the turbine outlet temperature are introduced as methods of increasing the surge margin. It is quantified that both methods have a substantial effect on the compressor surge margin. Furthermore, a comparison between both methods is given in terms of electric power output.