| 1. |
- Domellöf, Erik, 1970-, et al.
(författare)
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Atypical functional lateralization in children with fetal alcohol syndrome
- 2009
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Ingår i: Developmental Psychobiology. - : Wiley Periodicals, Inc. - 0012-1630 .- 1098-2302. ; 51:8, s. 696-705
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Tidskriftsartikel (refereegranskat)abstract
- In order to explore effects of prenatal alcohol exposure on functional lateralization, item tasks measuring preferences of hand, foot, eye, and ear were administered to a sample of 23 children diagnosed with fetal alcohol syndrome (FAS) compared with typically developing (TD) children. In addition, a dichotic listening task was administered to a subsample of 11 children with FAS and a TD group of comparable age, sex and handedness. The children with FAS were characterized by increased nonright-handedness compared with TD children. No differences were evident for preferential use of foot, eye, or ear. Moreover, children with FAS displayed more right ear extinctions during dichotic listening relative to TD children, indicating a lack of right ear advantage. The results add to findings of decreased manual asymmetry and less left-lateralized speech perception in children with developmental disorders, and are further discussed in relation to the high incidence of callosal abnormalities in alcohol-exposed children.
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| 2. |
- Domellöf, Erik, 1970-
(författare)
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Development of functional asymmetries in young infants : A sensory-motor approach
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human functional laterality, typically involving a right-sided preference in most sensory-motor activities, is still a poorly understood issue. This is perhaps particularly true in terms of what underlying mechanisms that may govern lateral biases, as well as the developmental origins and course of events. The present thesis aims at investigating functional asymmetries in the upper and lower body movements of young human infants. In Study I, the presence of side biases in the stepping and placing responses and head turning in healthy fullterm newborns were explored. No evident lateral bias for the leg responses in terms of the first foot moved or direction of head turning was found. However, a lateral bias was revealed for onset latency in relation to the first foot moved in both stepping and placing. Asymmetries in head turning did not correspond to asymmetries in leg movements. In Study II, functional asymmetries in the stepping response of newborn infants were investigated in more detail by means of 3-D kinematic movement registration. Evident side differences were found in relation to smoother movement trajectories of the right leg by means of less movement segmentation compared to the left leg. Side differences were also found in relation to intralimb coordination in terms of stronger ankle-knee couplings and smaller phase shifts in the right leg than the left. In Study III, using the same movement registration technique, the kinematics of left and right arm movements during goal-directed reaching in infants were prospectively studied over the ages 6, 9, 12, and 36 months. Main findings included side differences and developmental trends related to the segmentation of the reaching movements and the reaching trajectory, as well as the distribution of arm-hand-use frequency. The results from Study I and II are discussed in relation to underlying neural mechanisms for lateral biases in leg movements and the important role of a thorough methodology in investigating newborn responses. Findings from Study III are discussed in terms of what they imply about the developmental origins for hand preference. An emphasis is also put on developmental differences between fullterm and preterm infants. Overall, the studies of the present thesis show that an increased understanding of subtle expressions of early functional asymmetries in the upper and lower body movements of young infants may be gained by means of refined measurements. Furthermore, such knowledge may provide an insight into the underlying neural mechanisms subserving asymmetries in the movements of young infants. The present studies also add new information to the current understanding of the development of human lateralized functions, in particular the findings derived from the longitudinal data. Apart from theoretical implications, the present thesis also involves a discussion with regard to the clinical relevance of investigating functional asymmetries in the movements of young infants.
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| 3. |
- Domellöf, Erik, 1970-, et al.
(författare)
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Functional asymmetries in the stepping response of the human newborn : a kinematic approach
- 2007
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Ingår i: Experimental Brain Research. - : Springer Berlin/Heidelberg. - 0014-4819 .- 1432-1106. ; 177:3, s. 324-335
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Tidskriftsartikel (refereegranskat)abstract
- In order to investigate subtle expressions of functional asymmetries in newborn leg movements, kinematic registrations were made on a sample of 40 healthy fullterm newborn infants during performance of the stepping response. Time–position data were collected from markers attached to the hip, knee and ankle joints of the left and right leg, and movements of both legs recorded simultaneously. Findings included evident side differences in terms of smoother trajectories of the right leg as a consequence of less movement segmentation compared to the left leg. Additionally, analyses of intralimb coordination revealed side differences with regard to stronger ankle–knee couplings and smaller phase shifts in the right leg. The findings suggest that asymmetries in newborn stepping responses are present in terms of spatio-temporal parameters and intralimb coordination. No evidence of a lateral preference in terms of frequency of the first foot moved was found. The present study adds new understanding to the lateralized attributes of the stepping response in the human newborn and as such points to new directions of research on the nature of laterality in the future.
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| 4. |
- Domellöf, Erik, 1970-, et al.
(författare)
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Impairment severity selectively affects the control of proximaland distal components of reaching movements in children with hemiplegic cerebral palsy
- 2009
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Ingår i: Developmental Medicine & Child Neurology. - : Mac Keith Press. - 0012-1622 .- 1469-8749. ; 51:10, s. 807-816
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Tidskriftsartikel (refereegranskat)abstract
- This study explored proximal-to-distal components during goal-directed reaching movements in children with mild or moderate hemiplegic cerebral palsy (HCP); [seven females, fourmales;mean age 8y 6mo; SD 27mo], compared with age-matched, typically developing children (seven females, fivemales; mean age 8y 3mo [SD 25mo]. Severity of HCP was assessed following the approach of Claeys et al. Optoelectronic registrations were made during unimanual reaching-to-grasp and reaching-to-hit movements with both the affected non-preferred and unaffected with HCP, particularly those withmoderate impairment, displayed less optimal spatiotemporal organization of movements performed with the affected arm. Compared with the goal to hit, and increasingly with more severe impairment, children with HCP adapted to the goal to grasp by recruiting augmented shoulder movements when reaching with the affected side. A resulting impact on distal kinematics was found in shorter, straighter, and less segmentedmovement paths. Thus, depending on severity of hemispheric lesions and task complexity, unilateral brain injuries in HCPmay selectively affect neural pathways underlying both proximal and distal arm movement control. Levels of both ipsi- and ontralateral activation in relation to side and lesion severity should be considered in future studies on prehension movements in HCP.
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| 5. |
- Domellöf, Erik, 1970-, et al.
(författare)
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Kinematic measurement of goal-directed arm movements in children with fetal alcohol syndrome : A preliminary study
- 2008
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Ingår i: Developmental Medicine and Child Neurology, 50 (Suppl. 114), Kroatien 5-7 juni, 2008. - : Wiley Online Library. ; , s. 31-32
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Konferensbidrag (refereegranskat)abstract
- Objective: Inadequate nutritional status can lead to several preventable developmental disorders. Populations living at high altitude are particularly at risk. Our aim is to contribute to the general knowledge of nutritional status of children in Ladakh.Method: Review of the literature concerning nutritional status in micronutrients, especially among children living in the Himalayan regions.Results: Iodine deficiency is the most common cause in the world of preventable learning disability*. Although the extension of severe endemic areas has been reduced, it is estimated that around 200 million people in the world are still living in remote places at risk of severe iodine deficiency. A recent survey in the ‘sub-Himalayan goiter belt’ indicates that iodine deficiency continues to threaten the health of this population.Studies in the Kashmir Valley found that, despite abundant sunlight, vitamin D deficiency is highly prevalent. Vitamin A deficiency (VAD) is a well-known cause of child morbidity and mortality and of visual defect. In India, 52,000 children go blind every year on account of VAD, and vitamin A supplementation programs are ongoing. VAD and iodine deficiency disorders (IDD) often coexist in vulnerable groups. In Africa it was shown that in IDD- and VAD-affected children receiving iodized salt and concurrent vitamin A supplementation improves iodine efficacy. In the Tibet Autonomous Region the nutritional status of children is deficient in proteins, iodine, selenium, calcium, and vitamins A and D. Interaction between iron and VAD is well known as well.Conclusions: To our knowledge, data concerning nutritional status of children living in Ladakh are lacking. Micronutrient deficiency is a public health concern that has lead to supplementation programmes. As interactions between several micronutrients have been evidenced, more integrated, multifaceted programmes are needed. Despite significant progress in many regions, continuing efforts are needed to reach underserved populations.
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| 6. |
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| 7. |
- Domellöf, Erik, 1970-, et al.
(författare)
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Upper and lower body functional asymmetries in the newborn : do they have the same lateral biases?
- 2005
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Ingår i: Developmental Psychobiology. - New York : Wiley. - 0012-1630 .- 1098-2302. ; 46:2, s. 133-140
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Tidskriftsartikel (refereegranskat)abstract
- It is still an open question as to whether functional asymmetries in the human newborn derive from a single lateralized system or multiple subsystems based on different neural mechanisms. In the present study, asymmetries in head turning were compared to those in leg movements during stepping and placing, with the latter also being related to differences in leg mass. The effects of an active versus an inactive state or condition were examined for all three behaviors. No overall lateral biases were found for head turning or for the first foot to move in stepping and placing, and there were no concordances among them; however, there was an asymmetry in that the left foot had a shorter onset latency when compared to the right foot for both stepping and placing. Findings are discussed in terms of what they imply about underlying neural systems that have a bearing on expressions of newborn laterality, and also with regard to the impact of methodological differences in this area of study.
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| 8. |
- Fagard, Jacqueline, et al.
(författare)
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The role of the corpus callosum in the perception of reversible figures in children
- 2008
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Ingår i: Vision Research. - : Elsevier BV. - 0042-6989 .- 1878-5646. ; 48, s. 2451-2455
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Tidskriftsartikel (refereegranskat)abstract
- To test the role of interhemispheric competition through the corpus callosum in the perceptual alternation of reversible figures, we compared children with callosal pathology and typically developing children on a bistable stimulus task. The children with corpus callosum pathology reported significantly less changes of percepts per minute than the age-matched typically developing children. In addition, older typically developing children reported significantly more changes of percepts than the younger ones. These results support the hypothesis that the rate of reversal between two interpretations of a bistable stimulus may be partly mediated by the corpus callosum.
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| 9. |
- Jonsson, Bert, 1961-, et al.
(författare)
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Prospective head tracking : head movements, accuracy and timing in relation to a circular object motion
- 2009
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Ingår i: Current Psychology Letters. - : Centre PsyCLE. - 1379-6100. ; 25:1, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- In this study, kinematic and video recordings were made of the eye- and head tracking of an object revolving in a vertical plane in two groups of infants (6- and 12-month-old) and one group of adults. The study had two purposes. The first concerned infants' abilities to negotiate the target trajectory when being forced to extensively recruit the head. The second addressed the question whether the same underlying neural controller drives both eye- and head motor systems. It was found that head tracking ability is functional already in 6-month-old infants. However, infants of both age groups displayed more extensive head movements and less accuracy compared to adults. This finding is in line with previous research on one-dimensional horizontal head tracking in infants. Infants also showed less developed timing between head movements and vertical object motion, supporting the argument that both eye- and head tracking have a common developmental trajectory.
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