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Early experience with faces of a given racial type facilitates visual recognition for this type of face relative to others. To assess whether this so-called other-race effect can be reversed by subsequent experience with new types of faces, we tested adults of Korean origin who were adopted by European Caucasian families when they were between the ages of 3 to 9. The adoptees performed a face recognition task with photographs of Caucasian and Asian faces. They performed exactly like a control group of French participants, identifying the Caucasian faces better than the Asiatic ones. In contrast, a control group of Koreans showed the reverse pattern. This result indicates that the face recognition system remains plastic enough during childhood to reverse the other-race effect.

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The aim of the present study was to test whether breathing pattern conditioning may occur just after birth. We hypothesized that sensory stimuli signaling the resumption of maternal care after separation may trigger an arousal and/or orienting response accompanied with concomitant respiratory changes. We performed a conditioning experiment in 2-day-old mice by using an odor (lemon) as the conditioned stimulus (CS) and maternal care after 1 h without the mother as the unconditioned stimulus (US). Each pup underwent two acquisition trials, in which the CS was presented immediately before (experimental paired group, n = 30) or 30 min before (control unpaired group, n = 30) contact with the mother. Conditioning was tested by using noninvasive whole body plethysmography to measure the respiratory response to the CS for 1 min. We found significantly stronger respiratory responses to the CS in the experimental group than in the control group. In contrast, somatomotor activity did not differ significantly between groups. Our results confirm the sensitivity of breathing to conditioning and indirectly support the hypothesis that learned feedforward processes may complement feedback pathways during postnatal maturation of respiratory control.

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Residual activation of the cortex was investigated in nine patients with complete spinal cord injury between T6 and L1 by functional magnetic resonance imaging (fMRI). Brain activations were recorded under four conditions: (1) a patient attempting to move his toes with flexion-extension, (2) a patient imagining the same movement, (3) passive proprio-somesthesic stimulation of the big toes without visual control, and (4) passive proprio-somesthesic stimulation of the big toes with visual control by the patient. Passive proprio-somesthesic stimulation of the toes generated activation posterior to the central sulcus in the three patients who also showed a somesthesic evoked potential response to somesthesic stimulation. When performed under visual control, activations were observed in two more patients. In all patients, activations were found in the cortical areas involved in motor control (i.e., primary sensorimotor cortex, premotor regions and supplementary motor area [SMA]) during attempts to move or mental imagery of these tasks. It is concluded that even several years after injury with some local cortical reorganization, activation of lower limb cortical networks can be generated either by the attempt to move, the mental evocation of the action, or the visual feedback of a passive proprio-somesthesic stimulation.

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Simultaneous attention in the two visual fields and interhemispheric integration of visual information was studied in 19-23 and 24-28-month-old infants. The stimuli were schematic faces within which the pair of eyes was made of either two identical (two circles or two triangles) or two different eyes (triangle-circle, circle-triangle). The faces were presented either in one visual hemifield, on the right or left side of a central fixation point (unilateral presentation), or across the two visual hemifields (bilateral presentation), with one eye of the stimulus on each side of the fixation point. The task was an operant conditioning task where the children had to decide whether the shapes of the two eyes were identical or not. The results show that even the younger subjects were able to perform the task when presented in the unilateral presentation condition, whereas only children aged 24 months and older could learn the task when presented in the bilateral condition. It is concluded that simultaneous attention to the two visual fields and inter-hemispheric co-ordination of visual information emerge very late in development at about the age of 24 months.

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Three experiments investigated face processing in children with Williams syndrome (WS). In Experiment 1, the ability to discriminate different aspects of faces was compared between WS subjects and a group of children individually matched for chronological age (CA-matches) and another group matched for mental age (MA-matches). In Experiments 2 and 3, the ability to process the local and configural aspects of geometrical patterns and faces was assessed within the same groups of subjects. The results indicated that the WSs' overall performance on face recognition was below that of the CA-matches, but similar to that of the MA-matches. This study revealed in addition that the CA- and MA-matches showed a bias toward a configural mode of face and geometrical shape processing, whereas children with WS did not show any bias. These findings suggest that face processing undergoes an abnormal developmental course in WS.

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It has been argued that operant conditioning is the only type of long-term memory present in infants prior to 6 months of age. In this study, memory for faces was investigated in 3- and 6-month-old infants with a visual paired-comparison task. In Experiment 1, infants were habituated to a face presented in different poses; recognition was assessed after a 2-min or a 24-hr retention interval. The 6-month-old infants and the male but not the female 3-month-old infants exhibited novelty preferences. A 2nd experiment showed that 3-month-old female infants were delayed relative to male infants in their face-processing ability rather than in their memory capacity. The results of Experiment 3 demonstrated in 3-month-olds an electrophysiological correlate of delayed recognition memory. These findings are discussed in the context of the neural systems thought to be involved in visual recognition memory (but not in procedural memory), namely the limbic system.

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NASA: Recommendations from a workshop on Space Neuroscience Research held in Paris on April 22-24, 1997 are summarized. Research areas include the autonomic nervous system, development and neurobiology, posture and movement, visual perception, vestibular function, cognition, and human factors. Long-term neuroscience research studies are being planned for the International Space Station. Experiments in microgravity should be accompanied by appropriate, ground-based research on the effects of gravity.^ieng

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We evaluated the influence of prolonged weightlessness on the performance of three cosmonauts to bilateral symmetry detection in the course of a 15-day-long Russian-French mission CASSIOPEE 96 aboard the MIR station. We tested the influence of weightlessness on subjects' performance as a function of the retinal orientation of axis of symmetry. as a function of type of stimuli (closed versus multi-elements shapes) and as a function of visual field presentation (at fixation, left visual field. right visual field). The results indicate firstly a difference between presentation at fixation versus away of fixation. Away of fixation, no effect of microgravity on performance was shown. A hypothesis of hemispheric specialization for symmetry detection was not supported as well. At fixation, an effect of micro-gravity was shown and more interestingly, the effect was quite different as a function of type of shapes used. suggesting that symmetry detection is a multiple-stage process.

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Complex objects are better recognized under a specific orientation. When presented upside down, a face, even very familiar, is recognized with greater difficulty than when presented upright ("Inversion effect"). Up to now it was not possible to decide whether the direction provided by gravity or the one provided by the retina and the body constitutes the spatial reference involved in this "Inversion effect". Three cosmonautes learned photographed faces on the ground and had to recognize them both on ground and on flight. Other photographed faces were learned in flight and where presented for recognition on flight. Results show that the Inversion effect is still present on flight for faces that have been learned on ground as well as for those learned on flight. Persistence of the inversion effect in 0-G shows that gravity is not involved as a spatial reference in recognition of faces. Learning and recognition performances of faces learned in flight were significantly lower than performances for faces learned on ground. A possible role of gravity in configural processing, but not in the Inversion effect, is suggested.

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Simultaneous attention in the two visual fields was studied in 20-, 24- and 26-month-old infants. The stimuli were pairs of simple geometrical elements. The two elements were presented simultaneously either to one visual hemifield (unilateral presentation), on the right or left side of a central fixation point, or across the two visual fields (bilateral presentation), with one component on each side of the fixation point. The task was an operant conditioning task with two conditions. In the Position condition, subjects had to decide whether the two components were horizontally aligned or not. In the Shape condition, they had to decide whether the shapes of the two components were identical or not. The results show that even the youngest group of subjects was able to reach the learning criterion in the unilateral presentation condition, whereas reaching the learning criterion in the bilateral condition becomes possible only at the age of about 24 months. No differences in the subjects' performances were found to exist between the Position and Shape conditions. It is concluded that simultaneous attention to the two visual fields and the production of a unified response emerge very late in development at about the age of 24 months.

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We present the first assessment of motion vision in childhood autism. Postural reactivity to visually perceived motion was measured in five autistic children and 12 normal controls of the same chronological age. Anteroposterior as well as total body sway occurring on a force platform in response to movements in the visual environment were compared. Autistic children were posturally more unstable than normal children and quite insensitive to visually perceived environmental motion. Some implications of this impairment for sensorimotor and social communication development in infantile autism are discussed.

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It has been recently established in both adult monkeys and humans that visual recognition memory, as assessed with a preferential visual fixation technique, depends on the integrity of the neural structures situated in the medial part of the temporal lobe. This kind of memory has been observed in infant monkeys not earlier than day 15. Using a familiarization technique we established that this recognition memory is present in human infants as early as postnatal day 3 when a 2-min retention interval is used. This visual recognition memory might be controlled by subcortical structures. The possibility that the medial temporal structure involved in adult visual memory is operating at birth cannot, however, be ruled out.

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Development of face processing after unilateral brain lesions sustained before one year of age was assessed in children aged between seven and 10 years by various tasks involving face processing. Each child was paired with an age- and IQ-matched control. There were three unilateral right-hemisphere lesions and three unilateral left lesions. The results showed that some of the skills relative to face processing were preserved (or recovered?), whereas other skills were severely impaired; the pattern varied from one child to another. The existence of these dissociations shows that preservation of low-level visual processing together with exposure to the appropriate stimuli for several years is by no means sufficient for face processing skills to develop normally.

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A right hemisphere advantage was observed in a previous study of 4- to 9-month old infants presented with a face discrimination task (de Schonen & Mathivet, 1990). The present study was designed to investigate pattern processing by the two hemispheres and the interhemispheric communication of this processing. Infants aged 4 to 9 months were tested with divided visual field presentations in one or two discrimination tasks. Under both task conditions, the infants had to discriminate between two patterns in which only two local components differed. Under one condition the components of the patterns were arranged so as to produce a face-like pattern. Under the other condition the same components were arranged into arbitrary patterns that were not "good form" patterns. No performance asymmetry was observed with the arbitrary patterns; whereas, a right hemisphere (RH) disadvantage was observed with the face-like patterns compared with both the RH performances on the arbitary patterns and the left hemisphere (LH) performances on the face-like patterns. These results show that the RH advantage for individual face recognition is not due to a general immaturity or inability of the LH in pattern processing at this period of development, nor to a more specific inability in a local mode of pattern processing. On the other hand, the RH does not completely lack local processing capacity, but is at a disadvantage when this local mode of processing has to be used with face-like (or good form) patterns. The interhemispheric communication of visual discrimination learning was tested by measuring learning transfer between the visual fields. Contrary to de Schonen and Bry's study (1987) on faceness recognition, no data in favor of interhemispheric communication were recorded in the present study.

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From a study on 4 to 6 year-old children, Hatta (Hatta, Neuropyschologia 28, 1053-1062, 1990) concludes that (a) a left visual-field advantage develops at age 4 to 5 years in visuo-spatial stimulus recognition, and (b) since both the right visual-field advantage for verbal and the left visual-field advantage for visuo-spatial material develop at the same age, there is no support for the claim that the left and right hemispheres develop differentially. We contest these conclusions on the basis of our own infant studies which have shown a right visual-field advantage in 4 to 9 month-old infants for individual face recognition and more recently, for some aspects of visual patterns.

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A right-hemisphere advantage in a mother's face recognition task in infants aged between 4 and 10 months was found to exist by de Schonen, Gil de Diaz, and Mathivet. The present study was designed to test (a) whether the right-hemisphere advantage would still prevail if the task requirements were different from those in the previous study, and (b) whether any information was communicated from one hemisphere to the other. 18-42-week-old infants were presented with an operant conditioning situation where they had to discriminate between their mother's and a stranger's face within one visual hemifield. Transfer of learning from one visual hemifield to the other was also measured. The results confirm the existence of a right-hemisphere advantage in discriminating between face stimuli. This advantage was weaker in the female than in the male population. No hemispheric transfer of learning was observed to occur.

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Infants aged 12-26 weeks (3-6 months) were presented with a visual category discrimination learning task (normal vs scrambled faces) in the right or left visual field. Once they had reached the learning criterion, they were tested for transfer to the untrained visual field in order to establish whether visual experience can be communicated to the opposite hemisphere. Transfer of learning was found to occur in infants aged 19-26 weeks but not in younger ones. Neural pathways possibly forming the channels for this communication are discussed.

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The study of the influence of familiarity with mirrors on children's capacity to identify their reflected images permitted differentiation between two problems that confront the child in the mirror situation: (a) the identity of the image and (b) the capacity to relate mirror space to real space. Sixty children, 6 to 26 months old, without previous experience with mirrors, were observed systematically while discovering their mirror image and a reflected object. Their behavior was compared to a control group with habitual mirror familiarity. The results suggest that (a) self-recognition in the mirror is independent of the child's familiarity with reflecting surfaces and (b) the capacity to relate mirror to real space seems to be strongly influenced by previous experience with mirrors.

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While visually fixating on a central, coloured object, thirty-six infants aged between two and five months were presented with a peripheral target to the right or to the left of midline. Both objects were presented at two distances: either 30 or 90 cm from the infant. The extent of the effective visual field was measured by the presence and the latency of saccadic shifts of gaze from the fixation object toward the target object placed at varying degrees of eccentricity. The effective visual field expanded between two and four months. Near peripheral targets were detected at greater angles of eccentricity than those more distant, but this effect was modified both by age and by the distance of central fixation. For two- and three-month infants the effective visual field was most reduced when the central fixation object was placed at 30 cm and the target object at 90 cm. The ability to respond to peripheral objects more distant than the fixation object develops after three months.

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