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Missense variants in the NF2 gene result in variable NF2 disease presentation. Clinical classification of missense variants often represents a challenge, due to lack of evidence for pathogenicity and function. This study provides a summary of NF2 missense variants, with variant classifications based on currently available evidence. NF2 missense variants were collated from pathology-associated databases and existing literature. Association for Clinical Genomic Sciences Best Practice Guidelines (2020) were followed in the application of evidence for variant interpretation and classification. The majority of NF2 missense variants remain classified as variants of uncertain significance. However, NF2 missense variants identified in gnomAD occurred at a consistent rate across the gene, while variants compiled from pathology-associated databases displayed differing rates of variation by exon of NF2. The highest rate of NF2 disease-associated variants was observed in exon 7, while lower rates were observed toward the C-terminus of the NF2 protein, merlin. Further phenotypic information associated with variants, alongside variant-specific functional analysis, is necessary for more definitive variant interpretation. Our data identified differences in frequency of NF2 missense variants by exon between gnomAD population data and NF2 disease-associated variants, suggesting a potential genotype-phenotype correlation; further work is necessary to substantiate this.

Schwannomatosis comprises a group of hereditary tumor predisposition syndromes characterized by, usually benign, multiple nerve sheath tumors, which frequently cause severe pain that does not typically respond to drug treatments. The most common schwannomatosis-associated gene is NF2, but SMARCB1 and LZTR1 are also associated. There are still many cases in which no pathogenic variants (PVs) have been identified, suggesting the existence of as yet unidentified genetic risk factors. In this study, we performed extended genetic screening of 75 unrelated schwannomatosis patients without identified germline PVs in NF2, LZTR1, or SMARCB1. Screening of the coding region of DGCR8, COQ6, CDKN2A, and CDKN2B was carried out, based on previous reports that point to these genes as potential candidate genes for schwannomatosis. Deletions or duplications in CDKN2A, CDKN2B, and adjacent chromosome 9 region were assessed by multiplex ligation-dependent probe amplification analysis. Sequencing analysis of a patient with multiple schwannomas and melanomas identified a novel duplication in the coding region of CDKN2A, disrupting both p14ARF and p16INK4a. Our results suggest that none of these genes are major contributors to schwannomatosis risk but the possibility remains that they may have a role in more complex mechanisms for tumor predisposition.

PURPOSE: To evaluate the incidence of mosaicism in de novo neurofibromatosis 2 (NF2).METHODS: Patients fulfilling NF2 criteria, but with no known affected family member from a previous generation (n = 1055), were tested for NF2 variants in lymphocyte DNA and where available tumor DNA. The proportion of individuals with a proven or presumed mosaic NF2 variant was assessed and allele frequencies of identified variants evaluated using next-generation sequencing.RESULTS: The rate of proven/presumed mosaicism was 232/1055 (22.0%). However, nonmosaic heterozygous pathogenic variants were only identified in 387/1055 (36.7%). When variant detection rates in second generation nonmosaics were applied to de novo cases, we assessed the overall probable mosaicism rate to be 59.7%. This rate differed by age from 21.7% in those presenting with bilateral vestibular schwannoma CONCLUSION: This study has identified a very high probable mosaicism rate in de novo NF2, probably making NF2 the condition with the highest expressed rate of mosaicism in de novo dominant disease that is nonlethal in heterozygote form. Risks to offspring are small and probably correlate with variant allele frequency detected in blood.

ObjectivesCases of sporadic vestibular schwannoma (sVS) have a low rate of association with germline pathogenic variants. However, some individuals with sVS can represent undetected cases of neurofibromatosis type 2 (NF2) or schwannomatosis. Earlier identification of patients with these syndromes can facilitate more accurate familial risk prediction and prognosis.MethodsCases of sVS were ascertained from a local register at the Manchester Centre for Genomic Medicine. Genetic analysis was conducted in NF2 on blood samples for all patients, and tumour DNA samples when available. LZTR1 and SMARCB1 screening was also performed in patient subgroups.ResultsAge at genetic testing for vestibular schwannoma (VS) presentation was younger in comparison with previous literature, a bias resulting from updated genetic testing recommendations. Mosaic or constitutional germline NF2 variants were confirmed in 2% of patients. Pathogenic germline variants in LZTR1 were found in 3% of all tested patients, with a higher rate of 5% in patients SMARCB1 variants were identified within the cohort. Considering all individuals who received tumour DNA analysis, 69% of patients were found to possess two somatic pathogenic NF2 variants, including those with germline LZTR1 pathogenic variants.ConclusionsUndiagnosed schwannoma predisposition may account for a significant minority of apparently sVS cases, especially at lower presentation ages. Loss of NF2 function is a common event in VS tumours and may represent a targetable common pathway in VS tumourigenesis. These data also support the multi-hit mechanism of LZTR1-associated VS tumourigenesis.

To evaluate the incidence of mosaicism in de novo neurofibromatosis 2 (NF2).Patients fulfilling NF2 criteria, but with no known affected family member from a previous generation (n = 1055), were tested for NF2 variants in lymphocyte DNA and where available tumor DNA. The proportion of individuals with a proven or presumed mosaic NF2 variant was assessed and allele frequencies of identified variants evaluated using next-generation sequencing.The rate of proven/presumed mosaicism was 232/1055 (22.0%). However, nonmosaic heterozygous pathogenic variants were only identified in 387/1055 (36.7%). When variant detection rates in second generation nonmosaics were applied to de novo cases, we assessed the overall probable mosaicism rate to be 59.7%. This rate differed by age from 21.7% in those presenting with bilateral vestibular schwannoma20 years to 80.7% in those aged ≥60 years. A mosaic variant was detected in all parents of affected children with a single-nucleotide pathogenic NF2 variant.This study has identified a very high probable mosaicism rate in de novo NF2, probably making NF2 the condition with the highest expressed rate of mosaicism in de novo dominant disease that is nonlethal in heterozygote form. Risks to offspring are small and probably correlate with variant allele frequency detected in blood.

Motivated by accounts of concept use in autistic spectrum disorder (ASD), and a computational model of weak central coherence (O’Loughlin & Thagard, 2000) we examined comprehension and production vocabulary in typically-developing children, and those with ASD and Down syndrome (DS). Controlling for frequency, familiarity, length, and imageability, Colorado Meaningfulness played a hitherto unremarked role in the vocabularies of children with ASD. High Colorado Meaningful words were underrepresented in the comprehension vocabularies of 2- to 12-year-olds with ASD. The Colorado Meaningfulness of a word is a measure of how many words can be associated with it. Situations in which high Colorado Meaningfulness words are encountered are typically highly variable, and words with High Colorado Meaningfulness often involve extensive use of context. Our data suggest that the number of contexts in which a particular word can appear has a role in determining vocabulary in ASD. This suggestion is consistent with the weak central coherence theory of autism.

Ranald Roderick Macdonald (1945-2007) was an important contributor to mathematical psychology in the UK, as a referee and action editor for British Journal of Mathematical and Statistical Psychology and as a participant and organizer at the British Psychological Society's Mathematics, statistics and computing section meetings. This appreciation argues that his most important contribution was to the foundations of significance testing, where his concern about what information was relevant in interpreting the results of significance tests led him to be a persuasive advocate for the 'Weak Fisherian' form of hypothesis testing.

The study examined the effects of psychological response and gender on coping with late life widowhood. Forty-six men and 46 women (55 years +) were interviewed about their experiences of widowhood. Participants were classified as to whether they were coping well or less well. Data were analyzed using grounded theory, content analysis, and three-way loglinear analyses. Loglinear analyses revealed three-way interactions for Gender, Coping, and Response. Men who report feeling upset or selfish are more likely to be coping, as are women who report being comfortable alone. There were two-way interactions between Coping and Response and Gender and Response. Participants who talk to their dead spouse are more likely to be coping than those who do not. Those who “keep themselves to themselves” are more likely not to be coping than those who do not. Gender differences were found in psychological response. Differences were also found between those who coped and those who coped less well. The study has enabled the synthesis of quantitative and qualitative data to present a more complete view of late life widowhood than has previously been possible. In addition, the article draws attention to the importance of distinguishing between the effects of bereavement and those of widowhood.

Metrology applications commonly require non-contact, capacitive sensors for displacement measurements due to their nanometer resolution. In some metrology applications, for example, the measurement of roundness and spindle error motion, the displacements of stationary and rotating cylindrical artifacts are measured. Error from using a conventionally calibrated sensor with a non-flat (e.g., cylindrical) target is typically neglected, but these errors cannot be ignored for nanometer-level accuracy. The capacitance between a sensor and a cylindrical target is less than that of a sensor with a flat target, which causes four effects. As the diameter of the target shrinks, the sensitivity of the sensor increases, the sensing range decreases, the sensing range shifts towards the target, and the nonlinearity increases. These errors can be greatly reduced by either calibrating sensors with the correct target surface or by determining corrections for post-processing data. This paper quantifies and experimentally verifies these errors for a commonly used sensor, and a simulation of a nanometer-level measurement of out-of-roundness and spindle error motion demonstrates that measurement accuracy is improved with corrected sensitivities.

Capacitive displacement sensors are widely used in precision manufacturing and metrology because they measure displacements with nanometer resolution. Prior literature usually treats capacitive sensors consisting of electrodes arranged as parallel plates. In this work, the target electrode is spherical, which is common in machine tool metrology, spindle metrology, and the measurement of sphericity. The capacitance due to a gap between flat and spherical electrodes is less than that of two flat electrodes, which causes four effects. As the diameter of the target electrode is reduced, the sensitivity increases, the sensing range decreases, the sensing range shifts toward the target, and the sensor becomes nonlinear. This paper demonstrates and quantifies these effects for a representative capacitive sensor, using finite element analysis and experimental testing. For larger spheres, the effects are correctible with apparent sensitivities, but measurements with the smallest spheres become increasingly nonlinear and inaccurate.

Do the views and experiences of older widowed men regarding widowhood agree, and can they be explained in terms of notions of masculinity? Older widowed men were asked whether they believed men or women coped better. They were also asked about their own experiences. The paper discusses the similarities and differences between the views and experiences of these widowed men within a framework of masculinity. Men believe that women are better equipped to deal with widowhood. They explain this in terms of women’s domestic abilities and social skills, and men’s inability to talk about their emotions. These views can be understood in terms of masculinity. However, analysis of their experiences suggests that the picture is more complex. Men were found to be as socially engaged as women. Men showed a range of domestic abilities: some were keen cooks and houseproud, while others relied on ready meals and family support. Women believed that men received more support than they did; this was confirmed. Unexpectedly, men reported more depressive experiences than women. It is argued that the experiences of widowed men may be understood in a masculinity framework, if one incorporates notions of diversity and social change.

The distinction is made between fixed effects and random effects and applied to the analysis of experiments involving linguistic materials, where its use has become a contentious issue. Specifically, some researchers have argued that treating linguistic variables such as words as fixed effects in analysis of variance is fallacious. Methods for analyzing data containing two random-effect factors are reviewed, and the conclusion reached that the use of quasi-F ratios or their approximation by min F′ is often best practice. Alternative legitimate analyses are also discussed. Keywords: random effect; quasi-F ratios; min F′; counterbalancing

Structural equation modelling (SEM) is outlined and compared with two non-linear alternatives, artificial neural networks and “fast and frugal” models. One particular non-linear decision-making situation is discussed, that exemplified by a lexicographic semi-order. We illustrate the use of SEM on a dataset derived from 539 volunteers' responses to questions about food-related risks. Our conclusion is that SEM is a useful member of the armoury of techniques available to the student of human judgement: it subsumes several multivariate statistical techniques and permits their flexible combination, and it provides robust goodness-of-fit statistics and is available in (generally) easy-to-use computer packages. Although the number of tasks for which SEM provides a persuasive psychological model is small, it is very useful in identifying the important variables and their inter-relations that contribute to task performance, and thus can constitute a valuable intermediate staging point between raw data and a fully...

The principal novel feature of this paper is the notion that a coherent memory can be synthesised from a set of partially coherent memory fragments by maximising a particular function, Harmony (Smolensky, 1986). The appeal of Harmony is that it fulfils two functions: it is at the heart of the synthesis algorithm and it provides a natural measure for "feeling-of-knowing". The model is applied to feeling-of-knowing data, flashbulb memories, flashbacks, repression, dissociation, memory stability across repeated recalls, and the effects of cue size on retrieval.

The study reported here considers the deterrent effect of terrorist incidents on the rates of luggage theft in railway and underground stations. We selected for our task a well-publicized major terrorist incident that took place on 18 February 1991. The analysis of the data shows that in the periods immediately following the terrorist incident there was a sharp but short-lasting decline in the number of cases of luggage theft. This indicates that either increased police vigilance, or the fear of potential thieves that items of luggage might contain explosives, produces a definite if short dived deterrent effect. One of the most debated and controversial issues in modern criminal justice policy is that of general deterrence, i.e. the inhibiting effects of sanctions on the illegal activity of potential criminals. (Zimring and Hawkins 1973; Beyleveld 1979, 1980; Tittle 1980; Walker 1991). The underlying assumption of general deterrence theory and associated policy is that individuals calculate the risk involved in criminal activity and refrain from it, because of their fear of punishment. Used in this sense, deterrence assumes a rational calculation of benefits and risks, including the probability of detection as well as the severity and swiftness of punishment by the potential offender. Indeed, utilitarian writers and economic and modern classical theorists argue that the purpose of criminal justice is to create an organized system of official threats sufficient to outweigh the perceived benefits of committing a crime (Bentham 1789; Posner 1985; Walker 1991). Opponents of the validity of the concept of general deterrence, on the other hand, dispute the thesis that potential criminals calculate risks in a rational manner and reject the view that the perception of the danger that they will be apprehended and punished for their misbehaviour has any significant deterrent effect. They argue that people tend to commit offences almost irrespective of the risk involved.1 The identification and measurement of deterrence are notoriously difficult for researchers, because of the methodological and ethical problems involved. As Ash worth points out, satisfactory empirical evidence is difficult to obtain since 'the condi tions must be such that non-offending can safely be ascribed to the deterrent effect of the sanction rather than other factors' (Ashworth 1994).

The aim of this study was to develop a subjective memory questionnaire for use with elderly people after stroke. A 13-item questionnaire was devised using items identified by 10 stroke patients and taken from existing memory questionnaires. It was tested on 50 elderly stroke patients and 50 elderly control subjects. Validation was carried out using the Rivermead Behavioural Memory Test (RBMT) and a significant positive correlation was obtained ( r= 0.71 ; p

Background The Huntington’s disease quality of life questionnaire (HDQoL) is a disease specific measure of the impact of Huntington’s disease on everyday life as reported by patients. Aim The current study aimed to use the HDQol subscales to predict generic quality of life measures commonly used. Method Using data from an initial sample of one hundred and fifty two participants who completed the HDQoL, the SF-12 and EQ-5D questionnaires, linear regressions were carried out with EQS 5-D index score, SF12 Physical Component Score (PCS) and SF12 Mental Component Score (MCS) as dependent variables. The predictors were either the three HDQol Primary Scales (Physical and Cognitive, Emotions and Self, Services), or the six HDQol Specific Scales (Physical and Functional, Cognitive, Hopes and Worries, Mood State, Self and Vitality, Services). Results For EQS 5-D index score, the regression using the 3 primary scale predictors yielded an R2 of 0.61, with all 3 predictors being individually significant. The regression with the 6 specific scale predictors yielded an R2 of 0.66, with four specific scales (Physical and Functional, Cognitive, Mood State, Self and Vitality) being individually significant. For SF12 PCS and the 3 primary scale predictors, R2 was 0.63, with all the variables significant; with the 6 specific scale predictors, R2 = 0.66, only Physical and Functional and Services were individually significant. For SF12 MCS and the 3 primary scale predictors, R2 = 0.56: only Emotions and Self was individually significant. With the 6 specific scale predictors, R2 = 0.58, with Mood State, Self and Vitality, Cognitive, and Physical and Functional scales being individually significant. Conclusion Across all the analyses, R2 ranged from 0.56 to 0.66, indicating that the HDQoL scales provide reasonable predictions of general EQ-5D and SF12 scales.

Before I looked closely at the literature on visual neglect, I imagined that neglect phenomena would show discontinuities: the patient could report perfectly accurately material in the right visual field, but as test stimuli were moved to the left a threshold would be crossed and the patient would no longer be able to give reliable reports. Many contributors to this volume have shown in several ways that this is not true, and that, as Kinsbourne (1987) has long argued, neglect is a continuous phenomenon. I concentrate on just two papers in the literature which show that neglect is not an all-or-nothing phenomenon: these are Marshall and Halligan (1990) on bisection, and Marshall and Halligan (1989) on star cancellation. My aim is to show how parameters characterising these tasks can be derived and to suggest it might be fruitful to compare parameters between tasks.

Understanding the relationship between age and prospective memory may be increased by studying the distribution and constituents of incorrect responses. Failure to perform the right activity at the right time may manifest itself as an 'error of omission', in which no response is made at the critical moment, or an 'error of commission', in which the intended action is replaced by a related one. These may, in turn, result from breakdown of encoding/storage or from retrieval failure. Which error is made may depend on the nature of the task, the context or the available processing resources of the performer. Responses of a group of elderly people to the appointment item of the Rivermead Behavioural Memory Test were examined for frequency of occurrence of different types of error and their relationship to other variables. Logistic regression analysis was used to explore the contribution made by variables of anxiety, age and current intelligence to performance on the task. The results suggest that the relationship is a complex one, in which there is an inverse relationship between anxiety and intelligence, and error type is differentially related to low and high anxiety and to age.

Rules for writing certain phonemes (/s/, /z/, /r/, /t/ and /d/) in Pitman New Era shorthand are systematically examined and their frequency of usage estimated. In particular, we identify three types of rule (default rules, other rules and short forms) and suggest correspondences between them and the classification of words in standard English orthography as regular, exception and strange. Twelve experienced shorthand writers wrote to dictation, in shorthand, passages of prose and lists of nonsense words. With real words there were effects of word frequency on percent correct. These were strongest for short forms and weakest for default rules. Nonsense words were less accurately transcribed than real words, and this effect was particularly marked for vocalic /r/. We conclude that lexical effects are just as strong for shorthand (which is taught by explicit rules) as it is for English orthography (where the rules are less systematic). In particular, there is no support for the notion that shorthand...

A connectionist model is described, which accounts for data showing a “mask appropriateness” effect in word and letter recognition. In a backward-masking paradigm, if the letter fragment masks that are used are of a similar size to the word or word fragment they are masking, performance is better than if the masks are longer or discontinuous (Jordan, 1990). The model simulates these effects by adding to the familiar architecture of the interactive activation model “length” units, which are stimulated whenever word units of a particular letter length are active, and “mask” units, which are stimulated by masks of particular sizes and in turn stimulate length units. Detailed predictions of the model are examined for both forward and backward masking, and are found to be in good accord with the data.

We report two studies of the distinct effects that a word's age of acquisition (AoA) and frequency have on the mental lexicon. In the first study, a purely statistical analysis, we show that AoA and frequency are related in different ways to the phonological form and imageability of different words. In the second study, three groups of participants (34 seven-year-olds, 30 ten-year-olds, and 17 adults) took part in an auditory lexical decision task, with stimuli varying in AoA, frequency, length, neighbourhood density, and imageability. The principal result is that the influence of these different variables changes as a function of AoA: Neighbourhood density effects are apparent for early and late AoA words, but not for intermediate AoA, whereas imageability effects are apparent for intermediate AoA words but not for early or late AoA. These results are discussed from the perspective that AoA affects a word's representation, but frequency affects processing biases.

The study investigated the relationship between depressive feelings and coping amongst older widowed men and women. Participants were interviewed about their affective experiences of widowhood and completed two depression questionnaire assessments, the Symptoms of Anxiety and Depression Scale (SAD) and the Hospital Anxiety and Depression Scale (HADS). Participants were assessed as either coping or not coping. The results showed that both measures were effective at differentiating those who coped (Copers) from those who did not (Non-Copers) in the sample as a whole. Amongst the widows the HADS significantly differentiated the two groups. Amongst men, neither measure significantly distinguished Copers from Non-Copers. However, an examination of the interviews suggested that widowers reported depressive feelings significantly more often than widows. The results suggest that depressive feelings are associated with non-coping in older widowed people. There is also evidence to suggest that widows and widowers respond differentially to assessment measures.

The effect of long-term knowledge upon performance in short-term memory tasks was examined for children from 5 to 10 years of age. The emergence of a lexicality effect, in which familiar words were recalled more accurately than unfamiliar words, was found to depend upon the nature of the memory task. Lexicality effects were interpreted as reflecting the use of redintegration, or reconstruction processes, in short-term memory. Redintegration increased with age for tasks requiring spoken item recall and decreased with age when position information but not naming was required. In a second experiment, redintegration was found in a recognition task when some of the foils rhymed with the target. Older children were able to profit from a rhyming foil, whereas younger children were confused by it, suggesting that the older children make use of sublexical phonological information in reconstructing the target. It was proposed that redintegrative processes in their mature form support the reconstruction of detailed phonological knowledge of words.

Performance on the Rivermead Behavioural Memory Test (RBMT) of 43 residents of Part III homes was compared with performance on Raven's Coloured Progressive Matrices and the National Adult Reading Test (NART). Health, medication, self-care and social activity were also measured. Results show that although Raven's score was the best predictor of memory test performance, it had a high refusal rate. Age was not a significant predictor of overall memory test score but results were complicated by age of entry into Part III, with older people performing better on some items. Medication, in particular drugs acting on the central nervous system, enhanced performance on some items.

Two experiments investigated the development of the word length effect in children aged 4 to 10 years, comparing auditory and visual stimuli. The question addressed was whether word length effects emerged earlier with auditory presentation or visual presentation, or whether they emerged at the same age regardless of presentation modality. Results provided evidence that word length effects emerge earlier with visual than auditory presentation. The implication of our results is that with visual presentation, 4-year-olds engage in some form of verbalisation strategy that involves obtaining phonological representations of picture names and mapping them on to articulatory output plans. This strategy is clearly verbal in nature, but is not necessarily characterised as cumulative verbal rehearsal.

This paper has two goals: to demonstrate the importance of the feature representation chosen for a connectionist model, and to examine the properties of a particular model, the back-propagation algorithm, in conditions intended to simulate the ‘graceful degradation’ encountered in human ageing. In a concept learning simulation, the number of zero or near-zero values of the input features and in the responses of the hidden units was found to influence speed of learning, strength of response to a prototype, and performance with distorted input (the latter two being inversely related). Degradation of the network prior to learning enhanced prototype performance but disrupted distortion performance. In the light of these results we discuss the design of efficient learning algorithms and the potentiality of these networks as models for human ageing.

A short memory test that provides analogs of everyday activities was used to investigate the relationship between everyday memory, cognitive abilities, participation in social, domestic, and leisure pursuits, and health status among 94 community-dwelling people aged between 70 and 93 years. Multiple regression analysis revealed that while fluid intelligence was a significant predictor of performance on most of the memory items, age was also a significant predictor of performance on prospective and verbal memory items, over and above the effects of intelligence. Crystallized intelligence and years of formal education showed little predictive power, but an index of participation in social and domestic activities was a good predictor of verbal, visual, and spatial memory items. It is concluded that cognitive decline in aging involves more than a simple decline in fluid intelligence.

The Frenchay Activities Index (FAI), a brief scale developed to measure lifestyle in stroke patients, was given to 119 community-dwelling people, aged 70 years or older, in order to obtain a baseline estimate of social, domestic, and leisure activity among older people. Factor analysis identified three main factors, similar in composition to those previously reported. A general linear models regression analysis of selected variables indicated that both fluid intelligence and memory test performance were significantly associated with level of activity. There was no significant association with age or crystallized intelligence in this sample. An apparently strong bias towards higher levels of activity among female respondents was diluted when marital status was included in the equation. This study suggests that the FAI is appropriate for measuring levels of activity in community-dwelling older people and that such activity is related to current cognitive abilities.

An experiment is reported where subjects were required to describe picture postcards while trying to avoid words beginning with one of the consonants /ptkbd or g/. There are differences in the strategies used by different subjects, some subjects making more errors (failures to avoid forbidden words) with high frequency words, while other subjects make more errors with low frequency words. Systematic changes were observed in the frequency of classes of words other than the class of words being avoided, and these changes were consistent with the hypothesis that words beginning with a consonant that was similar to the forbidden consonant were used relatively less often than words beginning with a dissimilar consonant. However, the similarity between consonants was different for high and low frequency words. Low-frequency words showed a pattern of similarities similar to ‘acoustic’ confusions in perception, and it is suggested that such words are encoded phonemically by the subject; on the other hand high-frequency words showed a pattern of similarities which had a large articulatory component, and it was suggested that such words are encoded as articulatory events in terms of units larger than a phoneme.

Models for letter cancellation are developed, i.e. for tasks where subjects read a coherent piece of prose at the same time as trying to cancel every target letter they encounter. These models have two components (i) a model of how information is represented by the reader, (ii) a model of how this information is scanned to enable the reader to detect particular target letters. Models of representation range from a photographic image of the printed page to a sophisticated multi-level representation, and models of scanning range from a series of independent saccadic movements (like eye movements) to scans which take into account morphemic and syntactic structure. Several predictions about the detailed pattern of letter cancellation data are developed on the basis of these models, and these are tested on a data base collected by Smith and Groat (1979). While some support for the simpler models is forthcoming, only the most elaborate models (multi-level representation, syntactically guided scan) can fully account for all the data. While instances can be found where the cancellation task is clearly disrupting the reading task, much of the data are consistent with the notion that the letter cancellation task is not excessively intrusive, and our analyses can thus give us significant information about normal reading.

Critical notice of Richard C. Atkinson, Richard J. Herrnstein, Gardner Lindzey & R. Duncan Luce (Eds.), Stevens' handbook of experimental psychology, Second Edition. (1988). New York: John Wiley and Sons. Volume 1: Perception and Motivation. Pp. xiv + 905. ISBN 0–471–04203–X. Volume 2: Learning and Cognition. Pp. xiv + 1027. ISBN 0–471–04207–2. £160.00. This method taxes patience to the utmost, and could hardly have arisen in a country whose natives could be bored…. There is little of the grand style about these new prism, pendulum and chronograph-philosophers. They mean business, not chivalry. What generous divination, and that superiority in virtue which was thought by Cicero to give a man the best insight into nature, have failed to do, their spying and scraping, their deadly tenacity and almost diabolical cunning, will doubtless some day bring about. [James, 1890/1950, pp. 192–193]

It is argued that current scaling models when they are applied to perceptual and mnemonic processes are out of touch with psychological theory. As an alternative, a psychological model is proposed in which stimuli are analysed by a series of feature tests, each feature test being dependent on the results of earlier feature tests in the series and on the other features present in the stimulus. Computer programs are described which fit such models to data, the output of such programs being the best-fitting hierarchy of feature tests. Detailed analyses are produced for data drawn from studies of speech perception and memory for speech; differences between normal, deaf and aphasic subjects are also discussed. It is claimed that, in comparison with normal scaling methods or with descriptions based simply on raw confusions, this approach offers a more insightful analysis of such data.

Two experiments are reported which investigate the process of converting written English into speech. In Experiment I, subjects read aloud sentences that contained nonsense words, and the spelling and grammatical category of the nonsense word were systematically varied. The location of primary stress in each nonsense word was found to depend on the phonemic form, grammatical category, and spelling of the word, in ways similar to those predicted by Chomsky and Halle's (1968) stress assignment rules. Experiment II, in which subjects judged the morphemic structure and apparent foreignness of each of the nonsense words used in Experiment I, showed that many of the interactions observed between experimental factors in Experiment I could be interpreted in terms of morphemic differences between different groups of words. An additive model for the operation of these rules is proposed.

Four expeirments are described which investigate readers' performance with polymorphemic words. The first two experiments examine subjects' judgments about the morphemic status of prefixes. It is found that the “ideal” prefixed word is long, has the form prefix + word , shows little orthographic or phonological evidence against prefixation, is of low frequency of occurrence, and came into the language comparatively recently. Experiments 3 and 4 examine fluent reading via a letter cancellation task. The principal finding is that there is a pseudoaffix effect: the e 's in affixes and in nonaffixes composed of the same syllables are missed more often than e 's in other syllables. A model of reading, a prominent component of which is a prelexical parser, is discussed in the light of these results.

A technique for incorporating an experimenter's predictions of orderings of the treatment means into an analysis of variance testing procedure is presented. The experimenter's predictions are assessed in terms of a statistic based on the ordering of the means (e.g. Kendall's tau). The product of the significances of this statistic and of F is used to obtain the significance level. In comparison with other approaches simulations show this to be the most appropriate technique where the experimenter can predict the order of the treatment means but wishes to have reasonable power even if the predicted ordering is wrong.

Extends the theory presented in Smith et al. (1975) to larger confusion matrices. Stimuli and responses are described by a series of features which take a discrete set of values. Processing models are proposed where each feature is tested independently (Independence model), where the processing of a given feature depends on the responses that have been made in testing for other features (Response Conditional model) or where the processing of a given feature depends on whether other features have been correctly identified or not (Correct Conditional model). Computer programs are described which fit these models to arbitrarily large confusion matrices. Difficulties in interpreting the behaviour of these models with real data are reviewed and solutions are offered. These points are illustrated by detailed analyses of confusion matrices obtained in studies of speech perception, memory for speech and semantic memory.

Methods for incorporating ordinal assumptions into the analysis of the means of k treatments (k > 2) are critically reviewed. These methods are examined under three headings: (1) Global: statistics that give an overall assessment of the presence of a trend in the data (e.g. linear and isotonic regression); (2) Multiple comparisons: statistics based on the repetition (explicit or implicit) of comparisons between pairs of treatments; (3) Joint probability: two statistics are computed, one giving an overall assessment of the differences between the means, the other assessing the specifically ordinal information in the data; the joint significance level of these two statistics is then determined. Numerical examples of all the methods are provided.

Two studies of English speakers' understanding of the English spelling system are discussed. The first study is Groat's (1979) investigation of seven-year-old children's ability to assign stress appropriately to two-syllable nonsense words embedded in otherwise normal sentences. This work is compared with an earlier study of university students' performance on a similar task (Smith & Baker, 1976) and suggests that seven-year-olds are as sophisticated as adults in extracting many of the linguistic factors (vowel quality, syllable structure, syntactic category) which influence stress assignment, but they lack the ‘heterogeneous’ structure of the lexicon that is characteristic of the adult (i.e. a lexicon where different classes of word are subject to different rules). Furthermore it is shown that experience with Pitman's initial teaching alphabet (i.t.a.) leads to subtle differences in children's performance in this task, suggesting that children taught to read with i.t.a. are using different print-to-sound conversion rules even after they have transferred to traditional orthography.