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A Caramazza

Publications and source records attributed to A Caramazza.

At least 37 records · Page 2Linked to original sources
PubMed1999

The selection of determiners in noun phrase production.

Picture-word interference experiments conducted with Italian speakers investigated how determiners are selected in noun phrase (NP) production. Determiner production involves the selection of a noun's syntactic features (mass or count, gender), which specify the type of determiner to be selected, and the subsequent selection of a particular phonological form (e.g., the/a in English). The research focused on the syntactic feature of gender. Results repeatedly failed to replicate the gender-congruity effect in NP production reported with Dutch speakers (longer latencies for target-distractor noun pairs with contrasting as opposed to the same gender). It is proposed that the discrepant results reflect processing differences in lexical access in Italian and Dutch: The selection of determiners in Italian, but not in Dutch, depends on phonological properties of the word that follows it in the NP. Evidence consistent with this explanation was obtained in an experiment in which determiner selection in NP production was hindered by conflicting phonological information in the NP.

Adult↗
PubMed1999

Deficits in lexical and semantic processing: implications for models of normal language.

The investigation of language processing following brain damage may be used to constrain models of normal language processing. We review the literature on semantic and lexical processing deficits, focusing on issues of representation of semantic knowledge and the mechanisms of lexical access. The results broadly support a componential organization of lexical knowledge-the semantic component is independent of phonological and orthographic form knowledge, and the latter are independent of each other. Furthermore, the results do not support the hypothesis that word meaning is organized into modality-specific subcomponents. We also discuss converging evidence from functional imaging studies in relation to neuropsychological results.

Cognition Disorders↗
PubMed1998

Dissociable coordinate frames of unilateral spatial neglect: "viewer-centered" neglect.

Detailed analyses of reading and nonlexical tasks by three patients with unilateral spatial neglect (USN) secondary to stroke indicate that the USN in each of these patients affects the left side (contralateral to brain damage) of the viewer, with respect to the viewer's head, mid-sagittal plane of the body, or line of sight. In one case, the neglect was further specified as concerning the left side of the viewer's line of sight (the left half of her residual visual field). Thus, the frame of reference of USN in these three cases appears to have viewer-centered (in at least one case, specifically retinotopic) coordinates. The performance of these patients is contrasted to that of other patients in the literature whose USN appears to have a frame of reference with stimulus-centered or object-centered coordinates. These results are interpreted within a model of visual processing (adapted from Marr, 1980 and others) with at least three coordinate frames. It is argued that USN can affect one or more of these coordinate frames independently.

Aged↗
PubMed1998

More is not always better: a response to Roelofs, Meyer, and Levelt.

In a series of papers we have argued that the distinction between lemma and lexeme levels of representation in lexical access may be unnecessary. We pointed out that the evidence cited in support of this view is not incompatible with alternative accounts that do not assume a lemma level of representation. Furthermore, we argued that there are neuropsychological observations and results from tip-of-the-tongue (TOT) experiments that appear to be problematic for the lemma/lexeme distinction. Roelofs et al. [Roelofs, A., Meyer, A.S., Levelt, W.J.M., 1998. A case for the lemma/lexeme distinction in models of speaking: comment on Caramazza and Miozzo (1997). Cognition 69, 219-230.] have challenged our conclusions by attempting to demonstrate that (1) a model that incorporates the lemma/lexeme distinction can account for the putatively problematic neuropsychological and TOT data; (2) there are other data that appear to be problematic for a type of model that does not include a lemma level of representation. In the present paper we respond to these criticisms by showing (1) that the neuropsychological and TOT data still represent a challenge for the lemma/lexeme distinction, and (2) that the other evidence cited by Roelofs et al. is not incompatible with lexical theories that assume only one lexical layer.

Humans↗
PubMed1998

Domain-specific knowledge systems in the brain the animate-inanimate distinction.

We claim that the animate and inanimate conceptual categories represent evolutionarily adapted domain-specific knowledge systems that are subserved by distinct neural mechanisms, thereby allowing for their selective impairment in conditions of brain damage. On this view, (some of) the category-specific deficits that have recently been reported in the cognitive neuropsychological literature - for example, the selective damage or sparing of knowledge about animals - are truly categorical effects. Here, we articulate and defend this thesis against the dominant, reductionist theory of category-specific deficits, which holds that the categorical nature of the deficits is the result of selective damage to noncategorically organized visual or functional semantic subsystems. On the latter view, the sensory/functional dimension provides the fundamental organizing principle of the semantic system. Since, according to the latter theory, sensory and functional properties are differentially important in determining the meaning of the members of different semantic categories, selective damage to the visual or the functional semantic subsystem will result in a category-like deficit. A review of the literature and the results of a new case of category-specific deficit will show that the domain-specific knowledge framework provides a better account of category-specific deficits than the sensory/functional dichotomy theory.

Animals↗
PubMed1998

Impaired stimulus-driven orienting of attention and preserved goal-directed orienting of attention in unilateral visual neglect.

Neglect patients do not respond to stimuli presented on the side of space contralateral to the side of their brain lesions, indicating deficits to attentional or representational mechanisms. We describe a patient who shows a left neglect in normal reading and line bisection but an intact ability to locate the left end of the stimulus. Further tests showed that his seemingly intact ability to search into the "neglected" side was due to his ability to use local elements of the stimulus as cues in his serial search for the left end. The patient's left neglect was significantly reduced after he located the left end of the stimulus. In contrast, his neglect was not reduced by making the stimulus on the neglected side physically more salient. These results suggest that his neglect is due largely to an impairment of the mechanism mediating automatic, stimulus-driven orienting of attention. In contrast, the controlled goal-directed attentional search is largely preserved and can be used to alleviate neglect.

Apraxias↗
PubMed1997

The modality-specific organization of grammatical categories: evidence from impaired spoken and written sentence production.

We describe the case of a brain-damaged individual whose speech is characterized by difficulty with practically all words except for elements of the closed class vocabulary. In contrast, his written sentence production exhibits a complementary impairment involving the omission of closed class vocabulary items and the relative sparing of nouns. On the basis of these differences we argue: (1) that grammatical categories constitute an organizing parameter of representation and/or processing for each of the independent, modality-specific lexicons, and (2) that these observations contribute to the growing evidence that access to the orthographic and phonological forms of words can occur independently.

Aphasia↗
PubMed1997

Identity and similarity factors in repetition blindness: implications for lexical processing.

The influence of identity and similarity of repeated items on repetition blindness (RB) was investigated in two rapid-serial-visual processing (RSVP) tasks. In Experiment 1, the difference between correct recall for sentences containing repeated identical items and their controls was contrasted with the difference between correct recall for sentences containing pairs of orthographically similar items (fish-dish) and their controls. In Experiment 2 the same comparison was made between sentences containing repeated identical items and sentences containing pairs of orthographically identical items (the watch-to watch). The amount of RB elicited by the two conditions was measured at three different temporal lags. The results show that the function that describes performance over time for the repeated-identical (R-I) condition is different from that for the condition in which the items are orthographically similar (repeated-neighbor: R-N) or orthographically identical (repeated-homonym: R-H). The results are interpreted as suggesting that the decrements in performance observed for recall of the second occurrence of the repeated item in the R-I and the R-N and R-H conditions have different underlying causes.

Analysis of Variance↗
PubMed1997

The relation between syntactic and phonological knowledge in lexical access: evidence from the 'tip-of-the-tongue' phenomenon.

The relation between access to the syntactic and to the phonological features of words in lexical access is investigated in two experiments. Italian speakers were asked to provide the gender and partial phonological information of known nouns they could not produce at that moment, words that they felt were at the tip-of-the-tongue (TOT). In both experiments, subjects were able to provide information about the word they could not produce with better-than-chance accuracy. This was true not only for phonological information such as the initial phoneme of the word but also for the word's gender--a purely syntactic feature of nouns. However, analyses of the correlation between correct retrieval of the gender and the initial phoneme failed to reveal a positive relationship. This result is inconsistent with theories of lexical access the interpose two lexical nodes, lemma and lexeme nodes, between a word's semantic and phonological content. A model of lexical access that does not postulate the lemma/lexeme distinction is briefly discussed.

Adult↗
PubMed1997

Acquired dysgraphia in alphabetic and stenographic handwriting.

We report the unusual case of AZO, who professionally used handwritten shorthand writing, and became dysgraphic after a stroke. AZO suffered from a complex cognitive impairment, and part of her spelling errors resulted from damage to auditory input processing, to phonology-orthography conversion procedures and to the ortographic output lexicon. However, analysis of her writing performance showed that the same variables affected response accuracy in alphabetic and shorthand writing; and, that the same error types, including transpositions, were observed in all tasks in the two types of writing. These observations are consistent with damage to the graphemic buffer. They suggest that, in multiple-code writing systems (e.g., stenography, Japanese, or in the case of multilingual speakers of languages that use different spelling codes), the graphemic buffer is shared by all codes.

Agraphia↗
PubMed1997

Haptic processing by the left hemisphere in a split-brain patient.

We report the case of a patient who suffered an ischemic accident resulting in damage to the anterior part of the corpus callosum and to the white matter in the posterior right hemisphere. Recognition of two-dimensional haptic stimuli explored with the right hand was severely impaired. The deficit was not specific to the type of stimuli, since letters, digits and geometrical shapes were not correctly recognized. Poor performance was not due to a specific mode of haptic exploration, since deficits were also observed without active manipulation of the stimuli. In contrast, the patient correctly named visual letters presented in the right visual hemifield (left hemisphere), and recognized three-dimensional common objects palpated with the right hand. Comparable results were observed in a surgical split-brain patient tested as a control. We conclude that (i) the construction of spatial representations of haptic stimuli, such as two-dimensional stimuli or three-dimensional block letters, cannot be fully realized in the intact left hemisphere, this ability requiring the contribution of both hemispheres, and (ii) tests for correct naming of common objects do not provide sufficient evidence to establish the integrity of the system involved in the identification of haptic information processed by the right hand of split-brain patients.

Adult↗
PubMed1997

From graphemes to abstract letter shapes: levels of representation in written spelling.

The letter substitution errors of 2 dysgraphic subjects who, despite relatively intact oral spelling, made well-formed letter substitution errors in written spelling, were studied. Many of these errors bear a general physical similarity to the intended target. Analyses revealed that this similarity apparently was based on the features of the component strokes of letters rather than on visuospatial characteristics. A comparison of these subjects' letter substitution errors with those of 2 other individuals with brain damage, whose damage was at a different level of processing, revealed that the latter subjects' errors are not explicable in terms of stroke-feature similarity. Strong support was found for the computation of multiple representational types in the course of written spelling. This system includes a relatively abstract, effector-independent representational level that specifies the features of the component strokes of letters.

Aged↗
PubMed1997

Retrieval of lexical-syntactic features in tip-of-the-tongue states.

Italian speakers who signaled that they were in a tip-of-the-tongue (TOT) state were asked to recognize the grammatical gender and the initial and the final phonemes of the unavailable word. The proportions of gender and phoneme hits that occurred with "don't know" (DK) responses were adopted as baselines for chance-level performance. Participants were more accurate in recognizing the grammatical gender and the initial but not the final phoneme of target words when they were in TOT than in DK states. The availability of gender in TOT states suggests the independence of syntactic from phonological information in lexical access. However, the retrieval of gender was far from perfect for TOT words, and it was no better than recognition of the initial phoneme. These results are problematic for the notion that the selection of a lemma is synonymous with the retrieval of the word's syntactic features. The implications of these results for the distinction between lemma and lexeme levels of representation in lexical access are discussed.

Humans↗
PubMed1996

The treatment of anomia resulting from output lexical damage: analysis of two cases.

This study describes a treatment project, carried out with two anomic subjects, RBO and GMA failed to name pictures correctly as a consequence of damage to phonological lexical forms; their ability to process word meaning was unimpaired. Words that were consistently comprehended correctly, but produced incorrectly by each subject, were identified. Some words were treated, whereas some served as the control set. A significant improvement was observed in both subjects. As predicted by the model of lexical-semantic processing used as the theoretical background for the study, improvement was restricted to treated items and did not generalize to untreated words, not even to words that were semantically related to those administered during treatment. Improvement was long-lasting, as shown by the fact that 17 months post-therapy GMA's performance on treated words was still significantly better than before treatment. These results are discussed in relation to the claim that cognitive models can be profitably used in the treatment of language disorders.

Adult↗
PubMed1996

Temporal and spatial repetition blindness: effects of presentation mode and repetition lag on the perception of repeated items.

In this study, participants were asked to identify briefly presented 5-letter (Experiments 1-3) or 2-letter (Experiment 4) strings. Identical items in a repeated trial were identified worse than their counterparts in a nonrepeated trial, indicating repetition blindness (RB; N. G. Kanwisher, 1987). In Experiment 1, RB occurred regardless of whether items were presented successively or simultaneously. In Experiments 2-4, RB occurred regardless of whether 2 simultaneously presented items were spatially close or far apart. The magnitude of RB, however, varied with presentation mode and repetition lag: RB was smaller in simultaneous than successive presentation, and RB increased and then decreased with the number of items separating 2 identical ones. These results provide important constraints in the interpretation of RB. A model that attributes RB to the refractoriness of perceptual recognition units is proposed.

Discrimination, Psychological↗
PubMed1995

Spatially specific deficits in processing graphemic representations in reading and writing.

We report the performance of two brain-damaged subjects, HB and ML, whose spelling performance is characterized by selective impairment in processing the side of words contralateral to their brain damage. A striking feature of these patients' performance was the fact that their spelling errors in all tasks--written naming, written and oral spelling, and delayed copy transcription--almost exclusively concerned the right half of words (in the case of HB) or the left half of words (in the case of ML), regardless of length of the target response. These patterns of performance are interpreted as indicating damage at the level of the grapheme description computed in all spelling tasks. We also discuss the additional observations that HB tended to complete words with nonrandom letter sequences in misspelling the final half of the word and that ML tended to preserve the initial letter of the word (in forward but not backward spelling) even when she made errors on other letters in the initial half of the word. Finally, the relationship between these spatially specific impairments of reading and writing and their relationship to spatially specific deficits in non-lexical tasks is reviewed.

Aged↗