Biomedical subjects

Anneli Kylliäinen

Publications and source records attributed to Anneli Kylliäinen.

5 recordsLinked to original sources

PubMed2006

Skin conductance responses to another person's gaze in children with autism.

The effects of another person's gaze on physiological arousal were investigated by measuring skin conductance responses (SCR). Twelve able children with autism and 12 control children were shown face stimuli with straight gaze (eye contact) or averted gaze on a computer monitor. In children with autism, the responses to straight gaze were stronger than responses to averted gaze, whereas there was no difference in the responses to these gaze conditions in normally developing children. Thus, these results showed that eye gaze elicited differential pattern of SCR in normally developing children and in children with autism. It is possible that the enhanced arousal to eye contact may contribute to the abnormal gaze behaviour frequently reported in the context of autism.

Autistic Disorder↗

PubMed2006

Face and gaze processing in normally developing children: a magnetoencephalographic study.

Magnetoencephalography (MEG) was used to study the neural mechanisms underlying face and gaze processing in ten normally developing boys aged between 8 and 11 years and 12 adult males. The participants performed two tasks in which they had to decide whether images presented sequentially in pairs, depicted the same person or the same motorbike. In the first task, the participants saw pictures of faces in which the eyes were either open or shut and pictures of motorbikes. In the second task, participants saw pairs of faces with gaze averted to the left or right. In children there was no evidence of the face sensitive, low amplitude short latency (30-60 ms) activity seen previously in adults. A strong, midline posterior response at approximately 100 ms was observed in children, which was earlier and somewhat stronger to faces than to motorbikes; in adults the signal at this latency was weak. A clear face sensitive response was seen in adults at 135 ms, predominantly over the right inferior occipito-temporal regions. Although activity was observed in the children at the same latency, it was less prominent, not lateralized and was evoked similarly by faces and motorbikes. Averted gaze conditions evoked strong right-lateralized activity at approximately 245 ms in children only. These findings indicate that even in middle childhood the neural mechanisms underlying face processing are less specialized than in adults, with greater early activation of posterior occipital cortices and less specific activation of ventral occipito-temporal cortex.

Adult↗

PubMed2006

Face- and gaze-sensitive neural responses in children with autism: a magnetoencephalographic study.

Face and gaze processing were studied using magnetoencephalography in 10 children with autism and 10 normally developing children, aged between 7 and 12 years. The children performed two tasks in which they had to discriminate whether images of faces presented sequentially in pairs were identical. The images showed four different categories of gaze: direct gaze, eyes averted (left or right) and closed eyes but there was no instruction to focus on the direction of gaze. Images of motorbikes were used as control stimuli. Faces evoked strong activity over posterior brain regions at about 100 ms in both groups of children. A response at 140 ms to faces observed over extrastriate cortices, thought to be homologous to the N170 in adults, was weak and bilateral in both groups and somewhat weaker (approaching significance) in the children with autism than in the control children. The response to motorbikes differed between the groups at 100 and 140 ms. Averted eyes evoked a strong right lateralized component at 240 ms in the normally developing children that was weak in the clinical group. By contrast, direct gaze evoked a left lateralized component at 240 ms only in children with autism. The findings suggest that face and gaze processing in children with autism follows a trajectory somewhat similar to that seen in normal development but with subtle differences. There is also a possibility that other categories of object may be processed in an unusual way. The inter-relationships between these findings remain to be elucidated.

Autistic Disorder↗

PubMed2004

Attention orienting by another's gaze direction in children with autism.

BACKGROUND: The aim of this study was to investigate attention orienting triggered by another's gaze direction in autism. METHOD: Twelve high-functioning children with autism and gender- and age-matched normal control children were studied using two tasks. In the first task, children were asked to detect laterally presented target stimuli preceded by centrally presented facial cue stimuli in which gaze was either straight ahead or averted. The direction of the cue was either congruent, neutral, or incongruent with respect to the laterality of the target stimulus. In the second task, children were asked to discriminate the direction of eye gaze. RESULTS: The results showed that another person's static gaze direction triggered an automatic shift of visual attention, both in children with autism and in normally developing children. The children in both groups were also able to overtly discriminate the direction of the gaze. CONCLUSION: These results seem to suggest that, in children with autism, the visual system processes information about another person's gaze direction and sends this information to those areas that subserve reflexive attention orienting. However, future studies are needed to investigate whether the processing of eyes and gaze direction relies on similar neural mechanisms in children with autism and in normally developing children.

Attention↗

PubMed2003

Visual agnosia in a child with non-lesional occipito-temporal CSWS.

In this paper we describe a case of severe visual agnosia in a child with an electrophysiological pattern of continuous spike-wave discharges in slow sleep (CSWS) in the occipito-temporal regions. The neuropsychological spectrum related to this phenomenon is discussed. Published paediatric reports associate visual agnosia (i.e. an inability to recognize objects without impairment of visual acuity) mainly with symptomatic occipito-temporal aetiology (e.g. cortical dysplasia, vascular insults) and other neurological symptoms (e.g. autism). We describe a detailed 2 year electrophysiological and neuropsychological follow-up of an 8-year-old boy with sporadic seizures, occipito-temporal CSWS and visual agnosia. The growth and neurological development of the child had been considered as normal, neurological examination did not reveal any focal signs, visual acuity was intact and MRI was normal. First EEG and six consecutive 24 h video EEG recordings during the follow-up of 22 months showed continuous spike-and-wave activity covering over 85% of the non-REM sleep. According to structured neuropsychological tests (Wechsler Intelligence Scale for Children--Third Edition, A Developmental Neuropsychological Assessment (NEPSY), Test of Visual-Perceptual Skills, Corsi block, Hooper Visual Organization Test) the boy had normal verbal intelligence but major deficits in visual perception, especially in object recognition, impaired shape discrimination and detection, and poor copying skills. Attention and executive functions were intact. There were no difficulties in short- or long-term memory. Verbal cues and naming the objects improved visual memory. Tracing the objects with a finger or by moving the head improved object recognition. Currently the boy attends a special school with a rehabilitation plan including neuropsychological and occupational therapies. This case adds a new facet to the spectrum of neuropsychological deficits in children with CSWS. Sleep EEG should be included in the etiological studies of children with specific neuropsychological problems and detailed neuropsychological assessment is needed for diagnostic and rehabilitation purposes.

Agnosia↗