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Paola Marangolo

Publications and source records attributed to Paola Marangolo.

12 recordsLinked to original sources
PubMed2006

Functional anatomy of derivational morphology.

Lexical morphology involves two types of suffixes: inflectional suffixes, which have a grammatical function, and derivational suffixes with a word formation function. In this study, functional magnetic resonance imaging (fMRI) was used during processing of Italian derived and inflected words. In the derivational task, subjects were asked to produce nouns derived from verbs and from adjectives (e.g., to observe--observation; kind--kindness). After the presentation of the derived noun, they had to generate the corresponding verb (e.g., failure--to fail: generation task). In the inflectional task, subjects had to produce the past participle of the verb or the plural form of the adjective or the derived noun. Behavioural data were collected in separate sessions in two different conditions. In the first experiment, as in the fMRI study, vocal reaction times (RTs) were measured from the offset of the auditory stimulus to the onset of the participant's response. In the second experiment, run with a different group of participants, RTs were recorded starting from the onset of the auditory stimulus to the onset of the response. The fMRI results showed that, relative to the inflectional task and to a repetition task, the derivational task, but not the verb generation task, brought about an activation of left fronto-parietal regions, documenting a specific involvement of these areas in the processing of derived words. Although less extended, similar activation was found for verb inflection but was absent for noun and adjective plural forms. Analysis of behavioral data indicated that an explanation in terms of task difficulty was unlikely related to the imaging results.

Adult↗
PubMed2005

When "macrocefalo (macrocephalous)" is read "minicervello (minibrain)": evidence from a single case study.

We report the case of a patient who showed a marked deficit in compound reading after almost complete recovery from his aphasic disturbances. Omission of one of the two compound components was his most frequent type of error. The patient also produced many paraphasias, which always respected the compound structure of the target. Similar errors were found on tasks of naming and writing to dictation. A deficit in retrieving the verb component of verb-noun compounds was also observed, consistent with the patient's residual agrammatism, and with decomposition at some point in processing. We suggest that this pattern of performance is compatible with a dual route model that hypothesises two stages of compound retrieval, a whole word stage followed by a decomposition into two constituent morphemes.

Aphasia↗
PubMed2005

Analyzing aphasia data in a multidimensional symptom space.

The utility of single-case vs. group studies has been debated in neuropsychology for many years. The purpose of the present study is to illustrate an alternative approach to group studies of aphasia, in which the same symptom dimensions that are commonly used to assign patients to classical taxonomies (fluency, naming, repetition, and comprehension) are used as independent and continuous predictors in a multivariate design, without assigning patients to syndromes. One hundred twenty-six Italian-speaking patients with aphasia were first classified into seven classic aphasia categories, based on fluency, naming, auditory comprehension, and repetition scales. There were two goals: (1) compare group analyses based on aphasia types with multivariate analyses that sidestep classification and treat aphasic symptoms as continuous variables; (2) present correlation-based outlier analyses that can be used to identify individuals who occupy unusual positions in the multivariate "symptom space." In the service of the first goal, group performance on an external validation measure (the Token Test) was assessed in three steps: analyses of variance based on aphasia type, regressions using the same cut-offs for fluency, naming, comprehension and repetition as independent but dichotomous predictors, and regressions using the same subscales as continuous predictors (with no cut-offs). More variance in Token Test performance was accounted for when symptoms were treated as continuous predictors than with the other two methods, though use of independent but dichotomous predictors accounted for more variance than aphasia taxonomies. Thus, if we by-pass classical taxonomies and treat patients as points in a multidimensional symptom space, better predictions are obtained. Outlier analyses show that group results depend on heterogeneity among patients, which can be used as a search tool to identify potentially interesting dissociations. Hence this multivariate group approach is complementary to and compatible with single-case methods.

Aphasia↗
PubMed2004

"I can write seven but I can't say it": a case of domain-specific phonological output deficit for numbers.

While it is established that numbers represent a category-specific semantic domain being dissociable from other semantic domains, it is a debated issue whether the category-specific dissociability persists at a level of lexical processing or whether words and number words are processed by the same lexical mechanisms. In most of the documented cases of brain damage, lexical processing of words and number words was equally spared or impaired. Here, we describe the case of a patient who after recovering from his naming disorders, showed a selective deficit in the spoken production of numbers with spared number writing and number comprehension abilities. After having ruled out alternative interpretations, we can conclude that these results indicate that words and numbers are not only categorically organised at the semantic level but that they are also processed by different lexical mechanisms. In addition, the results argue in favour of the existence of different modality-specific output lexicons for the written and spoken production of numerals.

Cerebral Cortex↗
PubMed2004

Selective impairment for reading numbers and number words: a single case study.

The article reports the case of a patient who showed a selective inability in reading multi-digit numbers following recovery from aphasic disorders. Although his ability to read words, non-words, syntagms and sentences was almost preserved, he made errors with Arabic numerals and number words. Different types of errors with alphabetic material were also observed: he made only rare phonological substitutions with linguistic stimuli, whereas errors were almost always lexical in reading number words. A series of experiments showed that his ability to access number semantics was intact. In contrast, he selectively failed in all production tasks (including calculation), but only when the required response was in the oral output modality. This pattern was interpreted in terms of a selective deficit to the spoken number name production system. Furthermore, the different types of errors made with alphabetic materials belonging to the two classes of stimuli (numerical versus non-numerical) further support the hypothesis of a categorical organisation in the lexical-semantic system.

Anomia↗
PubMed2004

Metaphor comprehension in right brain-damaged patients with visuo-verbal and verbal material: a dissociation (re)considered.

Metaphor comprehension was investigated in 50 right-hemisphere damaged (RHD) patients and 38 control subjects in two experimental conditions: a visuo-verbal and a verbal test. In the visuo-verbal test, subjects had to match a metaphorical sentence with one of four pictures representing the correct metaphorical meaning, the literal meaning, a control metaphor and a control literal meaning. In the verbal test, a metaphorical sentence had to be matched to a correct written metaphorical interpretation, a literal or a control interpretation. On both tests, the number of correct metaphorical responses in the RHD group was lower than in the control group. However, RHD patients performed more poorly in the visuo-verbal than in the verbal condition. Interestingly, when they selected the wrong response, the RHD patients tended to select the literal one only in the visuo-verbal condition. Context does not seem to be responsible for the dissociation between the two tests. The influence of the RHD patients' major visuo-spatial deficits was also checked, to exclude their role in the tendency to be literal with visuo-verbal material. Results are discussed in the perspective of an integration deficit.

Aged↗
PubMed2004

Modality-specific naming deficit: cognitive and neural mechanisms implicated in naming to definition.

We report the case of an anomic patient who had a significantly greater impairment in naming to definition than in picture naming. His difficulty did not depend on the number of semantic attributes (two vs. four) or type of information (visual vs. non-visual) carried in the definition. When asked to visualize the perceptual characteristics of the stimulus by means of drawing, his performance on the naming to definition task improved significantly. We first discuss this performance pattern in terms of the debate between the modality access deficit hypothesis and the multiple semantics position. The patient's more severe impairment in naming to definition suggests that his dissociation may be due to a more selective involvement of verbal semantics. In line with recent PET findings indicating that top-down semantic-to-visual sensory neural feedback improves the retrieval of semantic information in naming to definition tasks, we hypothesize that the patient's difficulty in retrieving the name was due to his inability to automatically activate this pathway. Picture drawing facilitated his naming because it activated the visual system directly (through the structure description level), implementing the retrieval of semantic information.

Acoustic Stimulation↗
PubMed2004

Independent access to phonological and orthographic lexical representations: a replication study.

Traditionally, it has been assumed that written abilities are completely dependent on phonology (the so-called phonological mediation theory). In this view, the semantic system activates the phonological form of a word, which then activates the corresponding orthographic representation. This hypothesis predicts that in double naming tasks (two temporally close responses to the same picture in the two output modalities), the word selected for a written response will always correspond to the one selected for a spoken output. On the contrary,the orthographic autonomy theory hypothesises the independence of the written output lexicon, which, in the presence of severe damage to conversion procedures, could be directly activated from the semantic system. In this case, the theory predicts that double naming tasks give rise to lexically inconsistent responses.We describe a non-fluent aphasic patient, RA, with agrammatic speech and severe word- finding difficulties. He also presented with severe damage to the phonology-to-orthography and orthography-to-phonology conversion procedures. His performance on picture naming tasks was significantly worse in the spoken than in the written output modality. Errors were predominantly omissions. Few semantic paraphasias were present. Semantic errors did not arise from a deficit in the semantic system since the patient performed flawlessly on a semantic questionnaire and a word picture matching task and gave correct definitions of the items. Although not predicted by the phonological mediation theory, on double naming tasks the patient gave inconsistent responses (i.e. he correctly wrote the stimulus "z-e-b-r-a" but he orally produced "giraffe"). Taken together, these results further confirm the hypothesis that access to the orthographic form of words can be accomplished independently, without the mediation of phonology (the orthographic autonomy hypothesis).

Anomia↗
PubMed2003

Between language and space: a cross-domain interaction.

We document for the first time the effect of a spatial deficit on an spoken language task. Right brain-damaged patients with and without neglect were administered a task of emphatic stress. Patients listened to 60 subject-verb-object sentence pairs. The emphatic stress could be placed on the subject, on the verb or on the object word. Patients had to judge whether the two sentences were same or different for the position of the emphatic stress. The judgements were more impaired in patients with neglect and when the stress was placed at the beginning of the sentence (on the subject word), that is to say, at the leftmost location of a hypothetical spatial representation of the heard sentence. We hypothesize that auditory language undergoes a spatial transcoding, and that this transcoding is affected by the presence of a spatial bias like that observed in patients with neglect.

Acoustic Stimulation↗
PubMed2003

The right hemisphere involvement in the processing of morphologically derived words.

It is widely documented that the left hemisphere is dominant in all complex linguistic tasks, including the processing of inflectional morphology. Both in Italian and in other languages, patients with brain damage with a selective deficit in derivational morphology have never been reported. Here we present the unusual case of two patients with very similar right-hemisphere lesions, who in the absence of aphasic disorders showed a selective inability in producing derivational morphology. Although both patients were unimpaired in producing verb infinitives, they both showed a selective deficit in producing nouns derived from verbs. This difficulty was not present in deriving nouns from other grammatical categories, such as adjectives. Interestingly, both patients mostly substituted the derived noun with the past participle of the verb. This pattern of results documents for the first time a right-hemisphere contribution in the domain of derivational morphology.

Aged↗
PubMed2003

Dissociation between personal and extrapersonal neglect in a crossed aphasia study.

Abstract Several reports document crossed aphasia following a right cerebral infarct. However, few of them provide a detailed investigation of associated neuropsychological disorders. A personal neglect disorder with no difficulty in orienting attention in the contralesional space has not been frequently reported independently of lesion side for the language deficit. In most cases, the deficit is described in the acute period. We report the case of a patient who showed severe crossed aphasia several months after cerebral damage. In addition to his language deficit, he suffered from finger agnosia, acalculia, and right/left confusion. Although he was able to orient attention in the contralesional space, he had a persistent personal neglect disorder with severe difficulty in attending to his own body. Results suggest that right hemisphere language dominance does not preclude ipsilateral specialisation for other functions. Furthermore, the dissociation between the two spatial functions provides further confirmation that they are subserved by two independent systems.

Agnosia↗