| 1. |
- Domellöf, Erik, et al.
(författare)
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Kinematic characteristics of second‐order motor planning and performance in 6‐ and 10‐year‐old children and adults : Effects of age and task constraints
- 2020
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Ingår i: Developmental Psychobiology. - : John Wiley & Sons. - 0012-1630 .- 1098-2302 .- 0012-1649 .- 1939-0599. ; 62:2, s. 250-265
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Tidskriftsartikel (refereegranskat)abstract
- This study explored age‐related differences in motor planning as expressed in arm‐hand kinematics during a sequential peg moving task with varying demands on goal insertion complexity (second‐order planning). The peg was a vertical cylinder with either a circular or semicircular base. The task was to transport the peg between two positions and rotate it various amounts horizontally before fitting into its final position. The amount of rotation required was either 0°, 90°, 180°, or −90°. The reaching for the peg, the displacement of it, and the way the rotation was accomplished was analyzed. Assessments of end state comfort, goal interpretation errors, and type of grip used were also included. Participants were two groups of typically developing children, one younger (Mage = 6.7 years) and one older (Mage = 10.3 years), and one adult group (Mage = 34.9 years). The children, particularly 6‐year‐olds, displayed less efficient prehensile movement organization than adults. Related to less efficient motor planning, 6‐year‐olds, mainly, had shorter reach‐to‐grasp onset latencies, higher velocities, and shorter time to peak velocities, and longer grasp durations than adults. Importantly, the adults rotated the peg during transport. In contrast, the children made corrective rotations after the hand had arrived at the goal.
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| 2. |
- Rönnqvist, Louise, 1957-, et al.
(författare)
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Lateral biases in head turning and the Moro response in the human newborn : are they both vestibular in origin?
- 1998
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Ingår i: Developmental Psychobiology. - 0012-1630 .- 1098-2302. ; 33:4, s. 339-349
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Tidskriftsartikel (refereegranskat)abstract
- Head turning after release from the midline and the Moro response to a full-body drop in 15 full-term newborns lying supine on a custom-built platform was studied. While the lateral bias for head turning was not as pronounced as for the Moro response, it was still assumed in the ratio of 2 (right):1 (left) as predicted by Previc (1991). Onset latency and time-to-peak acceleration were both significantly shorter in the right arm during the initial phase of the Moro response. For both measures, this right arm bias persisted over four consecutive elicitations in most infants. Vaginally delivered infants and those born by Caesarean section did not differ in terms of head preference and the two measures of arm advantage. Our main finding was that infants with a right-sided head preference had a consistently shorter onset latency for the right arm. We interpret this association as stemming from a common labyrinthine asymmetry that involves different vestibulospinal pathways for the neck and arm muscles. In general, our findings are discussed in the context of Previc's (1991) left-otolithic dominance hypothesis and Grattan, De Vos, Levy, and McClintock's (1992) model of newborn functional asymmetries.
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| 3. |
- 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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| 4. |
- 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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| 5. |
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| 6. |
- Hansen, Stefan, 1953, et al.
(författare)
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The development of sexual behavior in the rat: role of preadult nutrition and environmental conditions.
- 1978
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Ingår i: Developmental psychobiology. - : Wiley. - 0012-1630 .- 1098-2302. ; 11:1, s. 51-61
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Tidskriftsartikel (refereegranskat)abstract
- Rats were subjected to pre- and postnatal undernutrition by restricting the food intake of their mothers (U); another group of rats was normally fed (N). Each nutrition group was divided into 3 subgroups by varying the degree of environmental stimulation: animals in the Max group were stimulated by handling and enriched rearing conditions; the Min group rats were subjected to social isolation; rats in the control condition (C) were raised under ordinary laboratory conditions. The onset of sexual activity was not affected in the U-C male rats, but was delayed in both U-Min and N-Min rats. Although no difference existed in the age of puberty between the N-Max and N-C animals, the U-Max rats displayed an advancement of puberty by 7 days in comparison to the U-C rats. Undernutrition did not affect female sexual maturation; however the Max condition delayed this process in both nutrition groups.
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| 7. |
- Hopkins, Brian, et al.
(författare)
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Facilitating postural control : effects on the reaching behavior of 6‐month‐old infants
- 2002
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Ingår i: Developmental Psychobiology. - : Wiley-Blackwell. - 0012-1630 .- 1098-2302. ; 40:2, s. 168-182
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Tidskriftsartikel (refereegranskat)abstract
- In this study, 3-D kinematic as well as 2-D videorecordings were made of the reaching behavior of infants aged about 6 months who were not yet able to sit. Detailed analyses of these recordings were directed toward specifying the effects of providing additional postural support to the lower body on the spatial and temporal features of such behavior. To detect these effects, reaching and associated head movements in this modified condition were compared to those made while the infants sat in an age-appropriate and commercially available chair lacking the supplementation of support for the pelvic region and upper legs. Findings consistent with predictions included better head stabilization and smoother reaching movements when the infants were in the modified chair. In addition, these two achievements were negatively related to reaching experience. These, and other findings, underscore the infrequently investigated supposition that changes in postural control induce improvements in the control of reaching movements during infancy. Recommendations are made about how the procedure adopted in the present study could be used in subsequent research to give further insights into the codevelopment of posture and action.
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| 8. |
- Johansson, Anna-Maria, et al.
(författare)
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Long-term influences of a preterm birth on movement organization and side specialization in children at 4–8 years of age
- 2014
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Ingår i: Developmental Psychobiology. - : Wiley Periodicals, Inc.. - 0012-1630 .- 1098-2302. ; 56:6, s. 1263-1277
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Tidskriftsartikel (refereegranskat)abstract
- This study explored upper-limb and head kinematics during unimanual goal-directed movements in children born preterm (PT) and full-term (FT) aged 4–8 years. Further, functional lateralization was investigated through side-specific kinematics and hand preference observations. Altogether, 141 children were included, divided into three sub-groups based on gestation week at birth (GW). Children born FT (38–41 GW) and moderately PT (33–35 GW) showed faster, smoother, and shorter movement trajectories than children born very PT (V-PT<33 GW). Only children born FT expressed evident side differences that were characterized by smoother movements with the preferred side. Regarding hand preference, the children born V-PT showed increased rates of non-right-handedness compared with the other groups. Regardless of hand preference, the children born V-PT showed less well organized movements compared with the other groups. These findings suggest that spatio-temporal movement organization and side specialization at pre-/early school-age are affected by a PT birth, and more frequently so for children born before 33 GWs, indicating long-lasting influences on neuromotor development and specialization.
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| 9. |
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| 10. |
- Rönnqvist, Louise, et al.
(författare)
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Quantitative assessment of right and left reaching movements in infants : a longitudinal study from 6 to 36 months
- 2006
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Ingår i: Developmental Psychobiology. - Hoboken : John Wiley & Sons. - 0012-1630 .- 1098-2302. ; 48:6, s. 444-459
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Tidskriftsartikel (refereegranskat)abstract
- This longitudinal study aimed to explore the early presence and developmental pattern of laterality in reaching kinematics and its relationship to side use. In order to do so, 3-D kinematic measurements as well as 2-D video recordings of right-left reaching movements were successively carried out for 17 infants at the ages of 6, 9, 12, and 36 months. Additional investigations of hand preference were made at 36 months. As four infants were prematurely born, their outcomes were compared to those of the fullterm participants. While most of the infants in the early ages showed a rather inconsistent preference in terms of frequency and distributions of right-left side use, the analyses of reaching kinematics revealed a more consistent pattern of fewer movements units (MUs) and straighter right-sided reaching for the majority of infants at all tested ages. However, reaching kinematics from the preterm infants were generally more variable and less side consistent. It is proposed that the development of human handedness originates from an early right arm rather than hand preference in that representations of asymmetry in bilateral projections (involved in arm movements) developmentally precede contralateral projections (involved in refined hand/finger movements).
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