ABSTRACT
The present study reports a case of dizygotic twins, one boy with Williams syndrome (WS) and one typically developing girl, and compares their neuropsychological profiles. The goal of the present authors was to verify whether the child with WS displayed a cognitive profile which is unique to the syndrome. Several tests designed to assess visuo-perceptual, visuo-motor, linguistic and memory abilities were administered to both children when they were 10.9 years old. Compared to his sister, the boy with WS displayed a homogeneous developmental delay in both non-verbal and verbal abilities. He achieved a level of performance similar to his sister only in facial recognition, phonological word fluency and memory for phonologically similar words. Furthermore, despite the overall delayed performance of the boy, both the twins displayed a cognitive profile characterized by strength in lexical comprehension and relative weakness in visuo-motor abilities.
Subject(s)
Diseases in Twins/genetics , Intelligence/genetics , Language Development Disorders/genetics , Psychomotor Disorders/genetics , Williams Syndrome/genetics , Child , Developmental Disabilities/diagnosis , Developmental Disabilities/genetics , Developmental Disabilities/psychology , Female , Humans , Language Development Disorders/diagnosis , Language Development Disorders/psychology , Male , Neuropsychological Tests , Psychomotor Disorders/diagnosis , Psychomotor Disorders/psychology , Twins, Dizygotic/genetics , Williams Syndrome/diagnosis , Williams Syndrome/psychologyABSTRACT
Recent studies on subjects with Williams syndrome (WS) have revealed a particular facility for language, rarely observed in other mental retarded populations, inspiring much belief in the independence of language from cognition. Lexical and morphosyntactic abilities of 17 Italian WS individuals, between 4.10 and 15.3 years of age, were evaluated both in comprehension and production and compared with those of normally developing Italian children. WS subjects look similar to normal controls in lexical comprehension, but they appear to perform more poorly in grammatical comprehension. Furthermore they look deviant from normals in some morphosyntactic aspects of their production. They perform better than normal controls only with respect to phonological fluency, when semantic aspects are not involved. Our data show very little evidence for a dissociation between language and cognition.
Subject(s)
Linguistics , Williams Syndrome/physiopathology , Adolescent , Child , Child, Preschool , Female , Humans , Italy , Male , Psychiatric Status Rating Scales , Williams Syndrome/psychologyABSTRACT
Williams syndrome (WS) is a genetic syndrome of abnormal neurodevelopment, characterised by a specific linguistic pattern. Comparing performances of WS subjects with those of normal children in a word span task, we found that WS subjects revealed normal phonological similarity and length effects but a reduced frequency effect. Our results suggest comparable phonological encoding mechanisms in WS and normal controls and, at the same time, it provides evidence for an impaired access to lexical-semantic knowledge in WS subjects. This dissociation fits well with the particular pattern of linguistic abilities of these subjects.
Subject(s)
Language Disorders/complications , Memory Disorders/complications , Semantics , Vocabulary , Williams Syndrome/complications , Child , Female , Humans , Language Disorders/diagnosis , Language Tests , Male , Memory Disorders/diagnosisABSTRACT
Williams syndrome (WS) is a rare genetic condition characterised by intellectual disability, typical facial dysmorphology and several medical anomalies. A specific neuropsychological profile with a dissociation between language (relatively preserved) and visuo-spatial abilities (more seriously impaired) has been hypothesised in these children. Memory abilities of these patients have not been adequately investigated, although they may substantially contribute to better understanding their neuropsychological profile. The present study aimed at investigating verbal and spatial memory in patients with WS (N = 16). Their performance was compared with that of normally developing children on tasks of verbal and spatial span and immediate and delayed recall of verbal and visuo-perceptual materials. Memory abilities of WS children appear to be characterised by defective visuo-spatial memory, both in the short-term and long-term domain, and a dissociation between normal short- but deficient long-term verbal learning. Results are interpreted by supporting the thesis that intellectual disability reflects the defective functioning of a complex system in which some cognitive competencies may be disrupted more than others (Detterman, 1987; Vicari, Albertini and Caltagirone, 1992).
Subject(s)
Intellectual Disability/diagnosis , Memory Disorders/diagnosis , Williams Syndrome/diagnosis , Child , Female , Humans , Intellectual Disability/psychology , Male , Memory Disorders/psychology , Memory, Short-Term , Orientation , Pattern Recognition, Visual , Psychomotor Performance , Retention, Psychology , Serial Learning , Verbal Learning , Williams Syndrome/psychologyABSTRACT
The authors report a longitudinal study of the first stages of cognitive, communicative and linguistic development of six Italian-speaking infants with unilateral brain lesions acquired before the point at which language acquisition normally would begin. Substantial variability was observed in the language-cognition profiles displayed by these children. To unify these diverse profiles, the authors propose a 'cognitive infrastructure' or 'threshold' model of early language development, in which the appearance of speech depends on the presence of certain cognitive prerequisites; once those are in place, some degree of dissociation between linguistic and cognitive development can be observed. The contribution of neurological factors to these profiles appears to be complex, suggesting an interaction between lesion site, lesion size and the presence of seizure disorders and/or anticonvulsant drugs.
Subject(s)
Brain Diseases/psychology , Cognition , Language Development , Speech , Age Factors , Brain Diseases/pathology , Female , Humans , Infant , Infant, Newborn , Italy , Longitudinal Studies , Male , Predictive Value of Tests , Psychological Tests , Severity of Illness IndexABSTRACT
An electroencephalographic (EEG) and behavioral model of head injury in unanesthetized, free moving mice has been used to test the effects of TRH and GM1. In our experimental conditions a mechanical head injury capable of inducing loss of righting reflex for 2 to 60 sec, also induces a consistent decrease of the total power of the spectrum of EEG and a decrease of the power of fast beta band (20-40 Hz) for at least 120 min. TRH, injected after trauma in dose of 10 mg/kg, caused improvement of EEG total power of the spectrum. GM1 in high (30 mg/kg) but not in low dose (5 mg/kg) caused more rapid restoration of both the total power and fast as well as slow beta band power. These results suggest that GM1 has favorable effects on post-concussive neurophysiological symptoms in head injured animals.
Subject(s)
Craniocerebral Trauma/physiopathology , G(M1) Ganglioside/therapeutic use , Thyrotropin-Releasing Hormone/therapeutic use , Animals , Craniocerebral Trauma/drug therapy , Disease Models, Animal , Electroencephalography , Male , MiceABSTRACT
Newborn mice were injected SC daily with 1 mg/kg of MIF-1 or saline during the first 19 days of life. The progress of each pup was monitored for physical (body weight, eye and ear opening), neurobehavioral (reflexes) and neurophysiological (EEG) development until the weaning stage. In early adulthood (40 days of age) mice were tested on a maze learning task. Results indicate that MIF-1 can accelerate neurologic (days 3-9), somatic (days 10-14) and electroencephalographic (days 16-19) parameters, and that the effects of treatment last into the early adult stage with increased learning abilities in an appetitive task.
Subject(s)
Electroencephalography/drug effects , MSH Release-Inhibiting Hormone/pharmacology , Motor Activity/drug effects , Reflex/drug effects , Amino Acid Sequence , Animals , Body Weight/drug effects , Learning/drug effects , Mice , Molecular Sequence Data , Signal Processing, Computer-AssistedABSTRACT
A quantitative EEG analysis was performed on the posterior lead of 18 patients with their eyes closed 3-10 days after minor head injury. There was a significant increase of the mean power of slow alpha (8-10 c/sec), a reduction of fast alpha (10.5-13.5 c/sec), with a shift of mean alpha frequency towards lower values, and a reduction of fast beta (20.5-36 c/sec) in the patients with head injuries compared with the age- and sex-matched patients in the control group. Therefore, power spectral EEG analysis performed with the above-mentioned criteria may be suggested as a sensitive tool to be added to others during the neurophysiological follow-up studies of people with head injuries.
