Origins of paraphasias in deep dysphasia: testing the consequences of a decay impairment to an interactive spreading activation model of lexical retrieval

This study investigates an account of atypical error patterns within the framework of an interactive spreading activation model. Martin and Saffran (1992) described a patient, NC, whose error pattern was unusual for the occurrence of higher rates of form-related than meaning-related word substitutions in naming and the production of semantic errors in repetition. They proposed that NC's error pattern could be accounted for by a pathologically rapid decay of primed nodes in the semantic-lexical-phonological network that shifts the probabilities of error outcome in lexical retrieval. In the present study, Martin and Saffran's account was tested and supported in a series of simulations that reproduce essential features of NC's lexical error pattern in naming and repetition. Also described here are the results of a longitudinal study of NC's naming and repetition, which revealed a shift in relative lexical error rates toward a qualitatively normal pattern. This change in error pattern was simulated by assuming that recovery reflects resolution of the rapid decay rate toward normal levels. The patient data and computational studies are discussed in terms of their significance for the understanding of aphasic impairments and their implications for models of lexical retrieval.     

Semantic priming and the word repetition effect in a lexical decision task.

Two experiments were conducted with 35 university students and community residents to examine the relationship between semantic priming and the word-repetition effect in lexical decisions. Although it might be expected that these phenomena are caused by the operation of similar memory processes, given current models of word recognition, the relationship between them has not been empirically investigated. In the present study, the persistance of both effects was observed, and it was found that while facilitation due to semantic priming persisted for only a short time, the word repetition effect was quite strong and long-lasting. (French abstract) (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Epidemiologic evidence for a causal relation between vaccination and fibrosarcoma tumorigenesis in cats

Within the past 2 years, a putative causal relationship has been reported between vaccination against rabies and the development of fibrosarcomas at injection sites in cats. A retrospective study was undertaken, involving 345 cats with fibrosarcomas diagnosed between January 1991 and May 1992, to assess the causal hypothesis. Cats with fibrosarcomas developing at body locations where vaccines are typically administered (n = 185) were compared with controls (n = 160) having fibrosarcomas at locations not typically used for vaccination. In cats receiving FeLV vaccination within 2 years of tumorigenesis, the time between vaccination and tumor development was significantly (P = 0.005) shorter for tumors developing at sites where vaccines are typically administered than for tumors at other sites. Univariate analysis, adjusted for age, revealed associations between FeLV vaccination (odds ratio [OR] = 2.82; 95% confidence interval [CI] = 1.54 to 5.15), rabies vaccination at the cervical/interscapular region (OR = 2.09; 95% CI = 1.01 to 4.31), and rabies vaccination at the femoral region (OR = 1.83; 95% CI = 0.65 to 5.10) with fibrosarcoma development at the vaccination site within 1 year of vaccination. Multivariate analysis, adjusted for age and other vaccines, also revealed increased risks after FeLV (OR = 5.49; 95% CI = 1.98 to 15.24) and rabies (OR = 1.99; 95% CI = 0.72 to 5.54) vaccination.(ABSTRACT TRUNCATED AT 250 WORDS)     

The relation between lexical marking and rating extremity in interpersonal judgment.

Results of 2 experiments with undergraduates (N = 35) support the following hypotheses: (a) Ss judge acquaintances more extremely on the "marked" (e.g., weak) than on the "unmarked" (e.g., strong) poles of dichotomous constructs represented by pairs of antonymous adjectives. (b) Ss use the unmarked poles of such constructs to describe their acquaintances more often than they use their marked opposites. (c) The greater the relative frequency with which an S uses the unmarked pole of a particular construct to characterize his acquaintances, the more useful he regards that construct for describing persons and the more extremely he rates his acquaintances on it. (French summary) (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Convergent behavioral and neuropsychological evidence for a distinction between identification and production forms of repetition priming.

Four experiments examined a distinction between kinds of repetition priming which involve either the identification of the form or meaning of a stimulus or the production of a response on the basis of a cue. Patients with Alzheimer's disease had intact priming on picture-naming and category-exemplar identification tasks and impaired priming on word-stem completion and category-exemplar production tasks. Division of study-phase attention in healthy participants reduced priming on word-stem completion and category-exemplar production tasks but not on picture-naming and category-exemplar identification tasks. The parallel dissociations in normal and abnormal memory cannot be explained by implicit-explicit or perceptual-conceptual distinctions but are explained by an identification-production distinction. There may be separable cognitive and neural bases for implicit modulation of identification and production forms of knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic, repetition and rime priming between spoken words: behavioral and electrophysiological evidence

Semantic, phonological and repetition priming for auditorily presented words were examined, using both behavioral reaction times (RTs) and electrophysiological event-related potentials (ERPs) measures. On critical trials, a word prime was followed by a word target that was semantically or phonologically related (rime) or not related (control) to the prime. Pairs of word-pseudoword items served as fillers. Participants were asked to respond to word targets in the RT experiment and to pseudowords in the ERP experiment. In each experiment stimuli were presented once and then repeated in the very same way. RTs were found to be fastest for semantic, intermediate for rime and slowest for control targets; large repetition effects occurred for all targets. ERPs results showed that both semantic and phonological priming influenced the same component, namely the N400, whose amplitude was smallest to semantic, intermediate to rime and largest to control targets; repetition effects were only found for semantic trials.     

First-language acquisition in adolescence: evidence for a critical period for verbal language development

It has been hypothesized that there is a critical period for first-language acquisition that extends into late childhood and possibly until puberty. The hypothesis is difficult to test directly because cases of linguistic deprivation during childhood are fortunately rare. We present here the case of E.M., a young man who has been profoundly deaf since birth and grew up in a rural area where he received no formal education and had no contact with the deaf community. At the age of 15, E.M. was fitted with hearing aids that corrected his hearing loss to 35 dB, and he began to learn verbal Spanish. We describe his language development over the 4-year period since his acquisition of hearing aids and conclude that the demonstrates severe deficits in verbal comprehension and production that support the critical period hypothesis.     

Speaking emotionally: The relation between verbal and vocal communication of affect.

20 male undergraduates role played 4 discrete emotions vocally using sentences whose semantic content was emotionally appropriate or affectively neutral. 48 undergraduate listeners attempted to identify the emotions from content-filtered recordings. With one exception, all emotions were recognized at above-chance levels; sadness was more accurately identified than anger, happiness, or surprise. However, an interaction revealed that the effect of semantic content depended on the emotion being expressed. For instance, semantically emotional (compared to neutral) material aided in the identification of sadness; however, the opposite was true for anger. Multidimensional scaling of listeners' confusions revealed 2 underlying affective dimensions termed "pleasantness" and "energy level." Analyses of dimensional coordinates indicated that regardless of affect, stimuli with neutral semantic content were perceived as having greater energy than those with emotionally appropriate content. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Orthography and phonology in lexical decision: Evidence from repetition effects at different lags.

Full- and partial- (orthographic or phonemic) repetition effects for Hebrew voweled and unvoweled words and nonwords were examined at Lags 0 and 15 between the first and the second presentations. For voweled words, phonemic and orthographic partial-repetition effects were equivalent at Lag 0, each about half the size of the full-repetition effect. At Lag 15, the full-repetition effect was reduced to the size of phonemic repetition, which was as big as it was at Lag 0. In contrast, the orthographic repetition effect disappeared. For unvoweled words, the phonemic repetition effect was significant only at Lag 0, whereas the full-repetition effect was significant at both lags. Lexical decisions for both voweled and unvoweled nonwords were facilitated only by full repetition at Lag 0. It was concluded that addition of vowel marks attracted the subjects' attention and, therefore, lexical decisions for voweled stimuli were mediated by phonemic analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word recognition cues used in matching verbal stimuli within and between auditory and visual modalities.

Administered a matching-to-sample task to 60 first graders under 4 conditions, 2 intra- and 2 intermodal. The 5 matching cues (letters and segments) were used differentially within the 4 conditions with the initial segment selected most frequently in all conditions. The 5 cues were also used differentially across the 4 task conditions. Cue choice was related to reading achievement in the visual-to-visual matching condition, with the good readers using the final word segment cue significantly more often than the initial and final consonant cue. The reading achievement of those selecting the reversal, initial word segment, or final word segment did not differ. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognition memory and familiarity judgments in severe amnesia: No evidence for a contribution of repetition priming.

The amnesic patient E.P. has demonstrated normal levels of repetition priming and at-chance recognition performance (S. B. Hamann & L. R. Squire, 1997), suggesting that the sense of familiarity used to make a recognition memory judgment is not based on the same mechanism responsible for repetition priming. However, the recognition tests previously used may have discouraged the use of familiarity and encouraged reliance on episodic memory. This issue was addressed in 5 experiments with E.P., 3 other amnesic patients with hippocampal damage, and 8 healthy controls. In Experiments 1–3, which were designed to discourage the use of episodic memory, the amnesic patients were impaired and E.P. performed at chance. In Experiments 4 and 5A, a stem-completion priming task was combined with a recognition memory task on each trial. E.P.'s priming was intact, yet his recognition memory performance was at chance. This suggests that although recognition memory judgments may be made on the basis of familiarity, repetition priming is not the source of this feeling of familiarity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Explicit memory and repetition priming in dementia: evidence for a common basic mechanism underlying conscious and unconscious retrieval deficits

The present study was designed to assess performance of Alzheimer's (AD) and Multi-infarct (MID) demented patients on the explicit and implicit versions of two memory tasks, namely Word-Stem Completion and Word-Pair Learning. Consistently with previous studies, the AD patients were deficient on the explicit and implicit versions of both tasks. In MID patients, a dissociation emerged between normal implicit and deficient explicit Word-Stem Completion. Two multiple regression analyses were performed to evaluate patients' ability on measures of lexical-semantic competence, explicit memory, and global intellective efficiency in predicting level of repetition priming. The results demonstrate a close association between explicit and implicit memory performance in AD patients but no relation between repetition priming level and measures of lexical-semantic competence or general intelligence. Overall, the results of the present study do not support previous conceptualizations suggesting that a breakdown in the structure of semantic memory is at the root of deficient priming in demented patients. Alternative interpretations of the deficient repetition priming effect in dementia, based on a common mechanism underlying conscious and unconscious retrieval deficits, are discussed.     

On the relation between feeling of knowing and lexical decision: Persistent subthreshold activation or topic familiarity?

Exp 1 replicated I. Yaniv and D. E. Meyer's (1987) finding that lexical decision and episodic recognition performance was better for words previously yielding high-accessibility levels (a combination of feeling-of-knowing and tip-of-the-tongue ratings) in comparison with those yielding low-accessibility levels in a rare word definition task. Exp 2 yielded the same pattern even though lexical decisions preceded accessibility estimates by a full week. Exp 3 dismissed the possibility that the Exp 2 results may have been due to a long-term influence from the lexical decision task to the rare word judgment task. These results support a model in which Ss (1) retrieve topic familiarity information in making accessibility estimates in the rare word definition task and (2) use this information to modulate lexical decision performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The specific relation between perception and production errors for place of articulation in developmental apraxia of speech

Developmental apraxia of speech is a disorder of phonological and articulatory output processes. However, it has been suggested that perceptual deficits may contribute to the disorder. Identification and discrimination tasks offer a fine-grained assessment of central auditory and phonetic functions. Seventeen children with developmental apraxia (mean age 8:9, years:months) and 16 control children (mean age 8:0) were administered tests of identification and discrimination of resynthesized and synthesized monosyllabic words differing in place-of-articulation of the initial voiced stop consonants. The resynthetic and synthetic words differed in the intensity of the third formant, a variable potentially enlarging their clinical value. The results of the identification task showed equal slopes for both subject groups, which indicates no phonetic processing deficit in developmental apraxia of speech. The hypothesized effect of the manipulation of the intensity of the third formant of the stimuli was not substantiated. However, the children with apraxia demonstrated poorer discrimination than the control children, which suggests affected auditory processing. Furthermore, analyses of discrimination performance and articulation data per apraxic subject demonstrated a specific relation between the degree to which auditory processing is affected and the frequency of place-of-articulation substitutions in production. This indicates the interdependence of perception and production. The results also suggest that the use of perceptual tasks has significant clinical value.     

Still no convincing evidence of a relation between brain size and intelligence in humans.

Replies to the comment by R. Lynn (see record 1994-24539-001) on M. Peters's (see record 1992-18876-001) claim that there is no association between brain size and IQ. It is countered that the available evidence is not strong enough to accept the proposition that brain size and IQ are positively correlated. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phonological priming in the lexical decision task: regularity effects are not necessary evidence for assembly

The contribution of assembled phonology in reading English was examined in the lexical decision task by comparing two markers: regularity effects and phonological priming. Strategic control was assessed by manipulating the phonological lexicality of the foils: Experiment 1 used legal nonwords, whereas Experiment 2 used pseudohomophones. Replicating existing findings, null regularity effects were obtained in the presence of legal nonwords. Modest regularity effects, in accuracy only, were observed with pseudohomophone foils. In contrast, phonological priming effects emerged in each of the experiments, regardless of the presence of regularity effects. Assembled phonology thus constrains reading under conditions that strongly discourage its use. However, regularity effects are not necessary evidence for its presence. The dissociation of regularity and phonological priming effects is discussed in terms of the two-cycles model.     

Learning correct responses and errors in the Hebb repetition effect: Two faces of the same coin.

In a serial recall task, the Hebb repetition effect occurs when recall performance improves for a sequence repeated throughout the experimental session. This phenomenon has been replicated many times. Nevertheless, such cumulative learning seldom leads to perfect recall of the whole sequence, and errors persist. Here the authors report evidence that there is another side to the Hebb repetition effect that involves learning errors produced in a repeated sequence. A learning measure based on past recalls (correct or incorrect) shows that the probability of a given response increases with the number of prior occurrences of that response. The pattern of results reveals another manifestation of the Hebb repetition effect and speaks to the nature of implicit learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of lexical frequency and syntactic complexity in spoken-language comprehension: Evidence from the auditory moving-window technique.

In 2 experiments, a new technique called the auditory moving window was used to investigate aspects of spoken-language processing. Participants paced their way through spoken sentences divided into word or wordlike segments, and their processing time for each segment was recorded. The 1st experiment demonstrated that high-frequency words in spoken sentences require less time to process than do low-frequency words. The 2nd experiment demonstrated that words in syntactically demanding contexts (i.e., the disambiguating word of so-called garden-path sentences) are processed longer than the same words in syntactically simpler contexts. Helpful prosodic information appeared to facilitate reanalysis of garden-path structures but did not seem to prevent the misanalysis. The implications of these findings for issues in spoken-language comprehension are discussed. The authors conclude that the auditory moving-window technique provides a useful tool for addressing largely unexplored issues in spoken-language comprehension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impaired generation and use of strategy in schizophrenia: evidence from visuospatial and verbal tasks

BACKGROUND: The aim of this study was to investigate mnemonic strategic deficits in schizophrenic patients. METHODS: Analogous tasks were used that required the self-generation of an efficient strategy and its implementation in two domains: visuospatial and verbal. The tasks were given to 20 IQ preserved schizophrenics and 20 matched normal controls. A number of different scores was derived from each task including strategy, short-term memory capacity and perseveration. RESULTS: Overall, the schizophrenic patients were significantly impaired in their ability to generate effective mnemonic strategies on both tasks. In addition, on the visuospatial task there was no difference between the groups on the memory scores, but the schizophrenic patients made significantly more perseverative errors than controls. They were disproportionately worse on the verbal strategy task, showing impairment on memory as well as on strategy scores and were also impaired at semantically classifying the words. Performance was similar to the deficit seen in patients with frontal lobe excisions and Parkinson's disease, in terms of the inability to generate an effective strategy. The deficit on the verbal task was similar to patients with temporal lobe excisions who show impaired verbal memory. However, the pattern differed in the sense that the temporal lobe patients were able to generate effective strategies, unlike the patients with schizophrenia. CONCLUSIONS: High functioning schizophrenic patients are impaired in utilizing visuospatial and verbal mnemonic strategies. By comparing the results with those of neurosurgical excision patients, further evidence is provided for both frontal and temporal lobe involvement in schizophrenia.     

Excitation produced by Schroeder-phase complexes: evidence for fast-acting compression in the auditory system

A series of experiments compared the excitation produced in an auditory filter centered on 1100 Hz by two complexes, both of which consisted of harmonics 2-20 of a 100-Hz fundamental. When the components had a level of 69 dB SPL each, summing them in positive Schroeder phase produced substantially less forward masking of an 1100-Hz signal than when the components were summed in negative Schroeder phase. This difference decreased with decreases in overall masker level. Listeners also reported that the components of the positive-phase masker close to 1100 Hz were quieter than the corresponding components in the negative-phase masker. The data are explained using Kohlrausch and Sander's [J. Acoust. Soc. Am. 97, 1817-1829 (1995)] finding that the response of an 1100-Hz auditory filter to the positive-phase complex shows marked peaks and dips, whereas that to the negative-phase complex does not. It is argued that the peaks in the response to the positive-phase masker are attenuated by fast-acting compression in the auditory system, thereby reducing the excitation produced by that sound. It is also argued that, compared to the power functions commonly used to model "excess masking" and the growth of loudness, the present data reflect greater compression at high levels but less compression at low levels.