Biomedical subjects

Nathalie Boddaert

Publications and source records attributed to Nathalie Boddaert.

21 records · Page 2Linked to original sources

PubMed2004

Perception of complex sounds in autism: abnormal auditory cortical processing in children.

OBJECTIVE: The authors have previously described less activation of left speech-related temporal areas in adults with autism when listening to speech-like sounds than in normal adults. Here, they investigated whether this abnormal cortical processing was also present in children with primary autism. METHOD: Regional cerebral blood flow was measured with positron emission tomography after premedication in 11 autistic children and six nonautistic mentally retarded children during rest and while they were listening to speech-like sounds. RESULTS: As with autistic adults, direct comparison between the two groups revealed significantly less activation in the autistic group localized in left speech-related areas. CONCLUSIONS: For the first time to their knowledge, an activation study was performed in children with autism and has confirmed previous results obtained in adults. The abnormal cortical auditory processing observed in both children and adults with autism could be involved in inadequate behavioral responses to sounds and in language impairments characteristic of autism.

Acoustic Stimulation↗

PubMed2003

Perception of complex sounds: abnormal pattern of cortical activation in autism.

OBJECTIVE: Bilateral temporal hypoperfusion at rest was recently described in autism. In normal adults, these regions are activated by listening to speech-like sounds. To investigate auditory cortical processing in autism, the authors performed a positron emission tomography activation study. METHOD: Regional cerebral blood flow was measured in five autistic adults and eight comparison subjects during rest and while listening to speech-like sounds. RESULTS: Similar to the comparison subjects, autistic patients showed a bilateral activation of the superior temporal gyrus. However, an abnormal pattern of hemispheric activation was observed in the autistic group. The volume of activation was larger on the right side in the autistic patients, whereas the reverse pattern was found in the comparison group. The direct comparison between the two groups showed that the right middle frontal gyrus exhibited significantly greater activation in the autistic group. Conversely, the left temporal areas exhibited less activation in autistic patients. CONCLUSIONS: These findings suggest that abnormal auditory cortical processing is implicated in the language impairments and the inadequate response to sounds typically seen in autism.

Acoustic Stimulation↗

PubMed2001

Functional neuroimaging and childhood autism.

Childhood autism is now widely viewed as being of developmental neurobiological origin. Yet, localised structural and functional brain correlates of autism have to be established. Structural brain-imaging studies performed in autistic patients have reported abnormalities such as increased total brain volume and cerebellar abnormalities. However, none of these abnormalities fully account for the full range of autistic symptoms. Functional brain imaging, such as positron emission tomography (PET), single photon emission computed tomography (SPECT) and functional MRI (fMRI) have added a new perspective to the study of normal and pathological brain functions. In autism, functional studies have been performed at rest or during activation. However, first-generation functional imaging devices were not sensitive enough to detect any consistent dysfunction. Recently, with improved technology, two independent groups have reported bilateral hypoperfusion of the temporal lobes in autistic children. In addition, activation studies, using perceptive and cognitive paradigms, have shown an abnormal pattern of cortical activation in autistic patients. These results suggest that different connections between particular cortical regions could exist in autism. The purpose of this review is to present the main results of rest and activation studies performed in autism.

Autistic Disorder↗