Sylvie Roux

Observation and execution of movement: similarities demonstrated by quantified electroencephalography

Quantified electroencephalography (qEEG) was used to compare cerebral electrical variations while human subjects (10 males and 10 females) were observing and executing finger movements and while they were resting. Video recording enabled elimination of subjects performing involuntary movements. EEGs were recorded from 14 sites in seven frequency bands: theta 1, theta 2, alpha 1, alpha, beta 1, beta 2 and beta 3. Analyses were performed on logarithmically transformed absolute spectral power values. Both observation and execution of finger movements involved a decrease in spectral power compared with resting. This decrease was significant only for the alpha 1 frequency band (7.5–10.5u2003Hz) and it involved nine of the 14 electrode locations (F7, F8, F4, T6, T5, C3, C4, P3 and P4). This indicates that the motor cortex and the frontal cortex are specifically activated by both observation and execution of finger movements. These results provide evidence that observation and execution of movement share the same cortical network.

Auditory associative cortex dysfunction in children with autism: evidence from late auditory evoked potentials (N1 wave–T complex)

OBJECTIVESnAuditory processing at the cortical level was investigated with late auditory evoked potentials (N1 wave-T complex) in 4-8-year-old autistic children with mental retardation and compared to both age-matched normal and mentally retarded children (16 children in each group).nnnMETHODSnTwo negative peaks which occurred in the 80-200 ms latency range were analyzed according to stimulus intensity level (50 to 80 dB SPL): the first culminated at fronto-central sites (N1b) and the second at bitemporal sites (N1c, equivalent to Tb of the T complex). The latter wave was the most prominent and reliable response in normal children at this age.nnnRESULTSnOur results in autistic children indicated abnormalities of this wave with markedly smaller amplitude at bitemporal sites and pronounced peak latency delay (around 20 ms). Moreover, in both reference groups the intensity effect was found on both sides whereas in autistic children it was absent on the left side but present on the right.nnnCONCLUSIONnThese findings in autistic children showing very disturbed verbal communication argue for dysfunction in brain areas involved in N1c generation i.e., the auditory associative cortex in the lateral part of the superior temporal gyrus, with more specific left side defects when auditory stimulus have to be processed.

Effects of oral stimulation and oral support on non-nutritive sucking and feeding performance in preterm infants.

This study compared the effects of oral stimulation with those of oral support on non‐nutritive sucking and feeding parameters in preterm infants. Preterm infants (23 males, 20 females) born between 29 and less than 34 weeks gestational age (GA; mean GA 31.2wks [standard error of mean{SEM} 0.39]; mean birth‐weight 1580g [SEM 120]) were allocated to one of three experimental groups: (Stimulation+support [five males, four females]; Stimulation [four males, seven females]; and Support [seven males, five females]) or a control group. Non‐nutritive sucking pressure and sucking activity were quantified in the gavage and transition periods. Oral support minimizes fluid loss, stabilizes the jaw, and organizes deglutition. The time of transition, the quantity of milk ingested per day, and the number of bottle feeds per day were recorded. Variables were analyzed by repeated‐measures analysis of variance, with birth‐weight as covariate (ANCOVA). Transition time was reduced (p<0.0001) for the Stimulation+support and Support groups. ANCOVA computed during gavage showed increased non‐nutritive sucking pressure and sucking activity (p<0.001) for the Stimulation and Stimulation+support groups. ANCOVA computed during transition revealed increases in non‐nutritive sucking pressure and daily bottle feeds (p<0.001) for the three experimental groups and in daily milk ingested (p=0.002) for the Stimulation+support and Support groups. We demonstrated that oral support is the result of both the action of chin and cheek support, and the aid to deglutition. An analysis of the organization of sucking patterns should be undertaken to provide better understanding of the mechanisms involved in oral support.

Validity and Reliability of the Infant Behavioral Summarized Evaluation (IBSE): A Rating Scale for the Assessment of Young Children with Autism and Developmental Disorders.

The Infant Behavioral Summarized Evaluation (IBSE) is a rating scale adapted from the Behavioral Summarized Evaluation (BSE) and specifically related to the assessment of behaviors of young children having autistic disorders. Content validity and reliability studies described in the paper were made from behavior ratings of videotapes for 89 children aged from 6 to 48 months. Results show a significant group of 19 items including some characteristic early autistic behaviors (communicative and social abnormalities) and some that are less commonly described in the syndrome (attentional, perceptive, and adaptive disorders). The value of the use of this scale for clinicians and professionals involved in behavioral evaluations and treatment of young children with developmental disorders and the necessity for further psychometric investigations are discussed.

The Behavioral Summarized Evaluation: Validity and Reliability of a Scale for the Assessment of Autistic Behaviors.

The Behavioral Summarized Evaluation (BSE), is a 20-item paper- and-pencil rating scale specifically designed for the measurement of behavioral parameters which could be related to biological data in autistic children involved in educational programs, neurophysiological studies, and therapeutic trials. The development of the scale, the validity, and reliability studies are presented in this paper. The results suggest that the BSE is an acceptable tool for the assessment of autistic behaviors, easy to handle, and accessible to both professionals and paraprofessionals of the medico-educative staff. It is a useful addition to the bioclinical researchers evaluation battery for bioclinical and therapeutic studies. However, more work is suggested to further investigate the psychometric properties of this behavior assessment instrument.

Validation of the Revised Behavior Summarized Evaluation Scale.

The Behavioral Summarized Evaluation scale (BSE), previously published and validated, was developed for the evaluation of the autistic behavior in developmentally disordered children. A revised version of this scale, the Revised Behavior Summarized Evaluation Scale (BSE-R) completed the 20-item BSE scale with the most relevant items extracted from a similar evaluation carried out with very young children. Thus 9 items were added to the original scale concerning nonverbal communication, emotional, and perception areas. This paper reports the reliability and validity studies of this new scale. In addition to confirming the previously published findings concerning the first version of the BSE, new items were extracted from the BSE-R content validity study. They involve fundamental functions such as intention and imitation which open new perspectives for a physiopathological approach to developmental disorders. The BSE-R is a useful tool for progressive recording of the evolution of patients both treated over long periods and included in short-term controlled therapeutic studies.

Cross-modal processing of auditory–visual stimuli in a no-task paradigm: A topographic event-related potential study

OBJECTIVEnThe aim of this study was to investigate in healthy adults the electrophysiological correlates of auditory-visual interactions involved in perception of bimodal events in a no-task paradigm.nnnMETHODSnEvent-related potentials were recorded in response to unimodal auditory (A), unimodal visual (V) and bimodal (AV) stimuli. Cross-modal interactions were estimated using the additive [AV-(A+V)] model.nnnRESULTSnThe spatio-temporal analysis of ERPs and scalp current densities revealed several interaction patterns occurring at both early and late stages of sensory cortical processing: (1) amplitude decrease of the unimodal auditory N1 wave as early as 55ms, (2) amplitude increase of the unimodal auditory P2 wave from 150 to 195ms concomitant with new neural activity over the right fronto-temporal region, and (3) amplitude increase of the late unimodal visual response within 245-350ms post-stimulus.nnnCONCLUSIONSnOur study provides evidence that several patterns of cross-modal interactions can be generated even if no task is required from subjects.nnnSIGNIFICANCEnThe paradigm used here can thus be utilized for studying the maturation of the cross-modal processes in young children and in children with pathological development.

Dysregulation of pretend play and communication development in children with autism

We hypothesized that the difficulties of the child with autism originate from disorders of organization and regulation of actions according to environmental changes. Autism impoverishes general mental representation skills, which are the basis of symbolic play and the development of communication. Twenty-one children with autism were compared with 14 children with global intellectual impairment and 15 matched typically developing children, on both regulation of play activities and communication development. Regulation of play was very disordered in children with autism, with breaking off, dissociation and instability of actions. However, in directed play their actions were more structured and corresponded to a better developmental level. In addition, dysregulation was associated with delayed, heterogeneous development of communication skills. The results of this study are in line with our hypotheses and emphasize the role of symbolic play in differential diagnosis and the value of therapies based on regulation processes and symbolic play.

Frontal auditory evoked potentials and augmenting-reducing

Auditory evoked potentials (AEPs) to tones (750 Hz--200 msec) ranging from 50 to 80 dB SPL were studied at Cz and Fz leads in 29 normal adults (15 males) ranging in age from 20 to 22. Peak-to-trough amplitudes were measured for the P1-N1 and the N1-P2 wave forms as well as baseline (500 msec prestimulus)-to-peak amplitudes for each component, i.e., P1, N1 and P2. Amplitudes were examined as a function of intensity and electrode location. Cz-Fz amplitude differences increased with increasing stimulus intensity, the differentiating peak being the N1 component. An overall reducing phenomenon was found at Fz in the 70-80 dB range whereas an augmenting effect was observed at Cz for these intensities. The augmenting/reducing groups defined by analysis of individual amplitude-intensity patterns were different whether we considered Fz or Cz results: Fz reducers were more numerous than Cz reducers. These results on prominent reducing at the frontal level were examined in relation to the data concerning the modulatory function of the frontal cortex on auditory EPs. Implications were drawn for the role of the frontal cortex in cortical augmenting-reducing.

Electroencephalographic activity during perception of motion in childhood.

The purpose of the present study was to relate observations of biological motion to cortical activity by evaluation of the association of quantified electroencephalogram (qEEG) parameters with a video film projection. Thirty right‐handed healthy children (2–8‐year‐olds) viewed a video film showing still shots and moving shots with human movement or object movement. The EEG was recorded while children watched the video movie and was then subjected to spectral analysis; the spectral powers for theta, alpha and beta bands were matched with corresponding sequences of video film. The power values of each frequency band were analysed in a four‐way repeated‐measures anova (Ageu2003×u2003Hemisphereu2003×u2003Electrodeu2003×u2003Sequence). Three main results were obtained: (i) younger children (2–4‐year‐olds) had higher power spectral values than older children (5–8‐year‐olds); (ii) greater EEG desynchronization of the left hemisphere was observed; (iii) observation of biological movement was related to a significant decrease in theta 1 and theta 2 power values of EEG in fronto‐temporal and central regions of the left hemisphere compared with visual perception of still shots or nonhuman movement. These results indicated some support for the theory that the sensori‐motor cortex and Brocas area are activated during visual observation of human motion.