Biomedical subjects

Daniela Brizzolara

Publications and source records attributed to Daniela Brizzolara.

8 recordsLinked to original sources

PubMed2006

Do phonologic and rapid automatized naming deficits differentially affect dyslexic children with and without a history of language delay? A study of Italian dyslexic children.

OBJECTIVE: The study aims to verify whether phonologic and rapid automatized naming (RAN) deficits are present and associated in Italian dyslexic children and whether they differentially affect dyslexics with and without a history of previous language delay (LD). BACKGROUND: According to the phonologic core deficit hypothesis, dyslexia may stem from impairment of the representation and manipulation of phonemes and may be closely associated with oral language deficits. However, deficits in tasks not requiring fine-grained phonologic representations, such as RAN, have also been described in dyslexic children. METHODS: Thirty-seven children were selected on the basis of a reading deficit and were assigned to 2 groups according to whether or not they had a history of early LD as determined retrospectively by parental report. A battery of reading and writing, verbal working memory, metaphonologic, RAN, and visual search tests were administered. RESULTS: RAN deficits were shared by most dyslexics (with and without a history of LD), whereas phonologic deficits were mainly associated with a previous LD. This last condition did not result in a more profound impairment of reading and writing decoding skills. CONCLUSION: In a shallow orthography such as Italian, RAN, not phonologic deficits, may represent the main cognitive marker of developmental dyslexia.

Adolescent↗

PubMed2006

Naming speed and visual search deficits in readers with disabilities: evidence from an orthographically regular language (Italian).

The study examined rapid automatized naming (RAN) in 42 children with reading disabilities and 101 control children-all native speakers of Italian, a language with shallow orthography. Third-, 5th- and 6th-grade children were given a RAN test that required rapid naming of color, object, or digit matrices. A visual search test using the same stimulus material (but not requiring a verbal response) and an oral articulation test were also given. Readers with disabilities performed worse than controls on the RAN test. This effect was larger in higher grades than in lower ones. Readers with disabilities were also slower than controls in performing the visual search test. The pattern of results for the RAN test held constant when the visual search performance was partialed out by covariance analysis, indicating the independence of the 2 deficits. The 2 groups did not differ for articulation rate. Finally, analysis of the pattern of intercorrelations indicated that reading speed was most clearly related to RAN, particularly in the group with reading disabilities. The results extend observations of RAN effects on reading deficits to Italian, an orthographically shallow language.

Attention↗

PubMed2005

Spatial and motion integration in children with autism.

Neuropsychological and psychophysical studies report controversial results regarding local-global visual processing and motion perception in autism. Here, we investigate contour integration and motion perception in an accurately diagnosed sample of autistic children, using low-level psychophysical tasks. We measured detection thresholds for a closed chain of Gabor patches, for different values of inter-element distance and we measured coherency thresholds of optic flow motion stimuli. Both experiments show comparable performances between autistics and normal subjects, demonstrating no evidence of early perceptual integration deficits. Some improvement in performance with age is detected in both groups.

Adolescent↗

PubMed2005

Hemispheric specialization for language in children with different types of specific language impairment.

The aim of the study was to investigate whether children with Specific Language Impairment (SLI) show reduced left hemisphere specialization for language and, if so, whether it is associated with a deficit in phonological encoding and a specific type of SLI (Mixed Receptive-Expressive, Expressive, Phonological). We adopted two dichotic listening paradigms, which differed in the phonological similarity of the presented words (Fused and Non-Fused dichotic words tests), as well as a phonological working memory test. Participants included 34 pre-school and school age children affected by SLI. On the dichotic tests, as a group the children with SLI showed a reduced pattern of left hemisphere specialization for language compared to age-matched normal children, with significant differences only in the Fused condition. However, the pattern of hemispheric specialization varied depending on the type of SLI, with reduced left hemisphere specialization in the Expressive type and, to a lesser extent, in the Phonological type of SLI, but not in the Receptive-Expressive type. The three subgroups also differed in phonological processing abilities and the incidence of a positive family history for language disorders: the Receptive-Expressive group performed worse on the working memory and dichotic tests and the Expressive and Phonological groups presented high frequency for familial language disorder. These results suggest that different subtypes of SLI are not different manifestations of the same underlying disorder, but represent pathological conditions that have distinct markers both at the behavioral and neurofunctional level.

Child↗

PubMed2005

Rapid naming, not cancellation speed or articulation rate, predicts reading in an orthographically regular language (Italian).

This study examined the influence of rapid automatization naming (RAN) measures on various parameters of reading performance in children who were native speakers of a language with a shallow orthography (Italian). Participants included 281 children enrolled in first-to-sixth grade. They were given a Naming test, in which they had to name rapidly matrices of colors, objects, or digits, a Cancellation test, using the same stimulus materials, and an oral Articulation test. Performance on all tests improved steadily across ages tested. Performance on the Naming test, but not on the Cancellation and Articulation tests, predicted speed and accuracy in reading; none of these measures reliably predicted the reading comprehension measure. Data on a Blending test were also available for a subsample of first- and third-graders. Both RAN and phonological ability contributed independently to the prediction of reading ability (accuracy and speed) in these participants. The results extend observations on RAN to an orthographically shallow language (Italian) and suggest an element of continuity between languages with opaque and transparent orthographies.

Awareness↗

PubMed2005

Abnormal phonologic processing in familial lateral temporal lobe epilepsy due to a new LGI1 mutation.

PURPOSE: Autosomal dominant lateral temporal lobe epilepsy (ADLTLE) is a rare familial epilepsy with onset in adolescence or early adulthood, associated with mutations of LGI1 in most families. We describe the clinical, neuropsychological, and molecular genetic study of a new ADLTLE Italian family. METHODS: A four-generation family from Sardinia was studied. Clinical, neuropsychological, and genetic analysis were performed in eight living affected family members. RESULTS: Nine family members had seizures over four generations; four of them had auditory auras and aphasia followed by secondarily generalized tonic-clonic seizures (SGTCs). One individual in addition had visual symptoms, and one family member had only vertigo followed by SGTCs. The side of seizure onset could not be determined in these five patients with focal seizures. The proband had febrile and afebrile tonic-clonic seizures. Two family members had only febrile seizures. Inheritance was autosomal dominant with 59% penetrance. Genetic molecular analysis showed a new LGI1 missense mutation causing a Leu154Pro substitution in six affected and one unaffected individuals. Dichotic listening performance was abnormal in four affected individuals compared with controls. Fluency and lexical abilities also were pathological in three patients. These findings showed that in patients, the left temporal lobe was less specialized in the auditory processing function than in controls. CONCLUSIONS: In this ADLTLE family, both seizure semiology and neuropsychological findings point to a lateral temporal lobe dysfunction. The newly identified LGI1 mutation might underlie both the seizure disorder and the neuropsychological deficits.

Adult↗

PubMed2002

Timing and type of congenital brain lesion determine different patterns of language lateralization in hemiplegic children.

Cerebral lateralization for language has been assessed by means of the Fused Dichotic Words Test in 26 hemiplegic children (mean age 7 years 2 months) with congenital focal brain damage (ten with left, seven with right and nine with bilateral lesions). The specific aim of the study was to investigate the relation between lesion characteristics (side, size and localization) at high field, multiple plane MRI and the pattern of language lateralization at the dichotic test. Significant side and site effects were found at group level; in children with lesions of the left hemisphere a left ear advantage (LEA) was found, while children with right lesions had the expected right ear advantage (REA). Analysis of individual data, however, revealed that type of lesion, cortical-subcortical or periventricular, occurring at term or preterm age, respectively, may be the primary factor responsible for inter versus intrahemispheric organization of language after congenital brain lesions. Only when the left lesions involved cortical-subcortical regions encroaching the temporal lobe and occurred at term age, was language reorganized in the right hemisphere; when lesions (whether left or right) involved only the periventricular white matter and occurred at preterm age, language was lateralized in the left hemisphere. Our results provide evidence that within 'congenital hemiplegias', strictly defined as hemiplegias whose causal lesion occurs before the end of the neonatal period, different recovery mechanisms are at work, depending on the type of brain lesion (neuropathology) which largely depends on the timing of insult (preterm vs. term period).

Brain↗

PubMedDate not supplied

A case of amnesia at an early age.

A dissociation between short- and long-term memory (LTM) and between the episodic and the semantic component of LTM is reported in a young girl who became amnesic at the age of 6 after an episode of acute encephalopathy resulting in bilateral frontal, insular, thalamic, ponto-mesencephalic, hippocampal and temporal lesions, as documented by MRI. The girl became amnesic a few months after starting school. A follow-up investigation showed that she was able to learn to read, write and acquire number facts and procedures and to improve her semantic knowledge. Our results show that the features of adult amnesia can also be found in children and that new semantic knowledge can be acquired in spite of an anterograde memory deficit. This dissociation does not agree with theories viewing long-term declarative memory as a unitary process mediated by the hippocampal system, but supports recent hypotheses that the acquisition of semantic knowledge is independent from episodic memory processes, and takes place through spared cortical regions subjacent to the hippocampi (Vargha-Khadem et al., 1997).

Amnesia↗