| 1. |
- von Hofsten, Olov, et al.
(författare)
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Simulating newborn face perception
- 2014
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Ingår i: Journal of Vision. - : Association for Research in Vision and Ophthalmology (ARVO). - 1534-7362. ; 14:13, s. 16-
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Tidskriftsartikel (refereegranskat)abstract
- A frequently asked question concerns what a newborn infant can actually see. The contrast sensitivity function of newborn infants is well known, but its implications for the ability of newborns to perceive faces of adults remain unclear. We filtered gray scale animations of facial expressions in terms of both spatial frequency and contrast to correspond to the properties of newborn infants' acuity and showed them to adult participants. We reasoned that if adults were unable to identify the depicted facial expressions, then it would also seem unlikely that newborn infants could identify the same expressions. We found that for the simulated acuity the different expressions could be rather well identified at a distance of 30 cm, but when the distance was increased to 120 cm their discriminability was much degraded. This shows that although the perception of faces and facial expressions can function at the low visual resolution of the newborn infant, it is insufficient for distinguishing faces and facial expressions at moderate distances.
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| 2. |
- Achard, B., et al.
(författare)
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Development of the infant's ability to retrieve food through a slit
- 2002
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Ingår i: Infant and Child Development. - : Wiley. - 1522-7227 .- 1522-7219. ; 11:1, s. 43-56
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Tidskriftsartikel (refereegranskat)abstract
- The main purpose of the present study is to explore infants' ability to comprehend task manipulation, and whether they can feed themselves with a spoon when food has to be retrieved through a slit in a lid placed over a plate. To access the food, the infant has to align the bowl of the spoon with the slit. The orientation of the slit is manipulated, and certain orientations require more elaborate modifications of the feeding action than others. The infants are observed at monthly intervals, from 12 to 17 months of age. The presence of the lid affects the behaviour of the infants at all ages. Some behaviours become more immature. The infants grasp the spoon with more primitive grasp configurations, they grasp the spoon less consistently at the top of the handle, and they orient the spoon less consistently, with its bowl facing upwards. These differences decrease with age. The infants also make attempts to adjust to the constraints of the task, mainly by inclining the spoon more vertically, and rotating the hand in such a way as to align the spoon with the orientation of the slit. These adjustments improve with age.
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| 3. |
- Andersson, Patrik, et al.
(författare)
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Readability of vertically vibrating aircraft displays
- 1999
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Ingår i: Displays (Guildford). - 0141-9382 .- 1872-7387. ; 20:1, s. 23-30
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Tidskriftsartikel (refereegranskat)abstract
- Vibrations pose a problem to the visual system. The vibrations in aircraft are mainly vertical and cause reading errors when the pilots read the instruments. In three experiments, reading capability was tested during vertical vibration of modern military aircraft, using symbols presented on a computer monitor. The results showed that complexity of symbols have a significant effect on the performance. The orientations of symbols were also of importance for their readability. Indexes made up of horizontally oriented lines were found to be especially difficult to read during vertical vibration. Orienting them 45° up or down improved readability in a significant way. The size of the symbols was found to be of importance especially when they were horizontally oriented.
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| 4. |
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| 5. |
- Bakker, Marta, et al.
(författare)
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Development of social perception : A conversation study of 6-, 12-and 36-month-old children
- 2011
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Ingår i: Infant Behavior and Development. - : Elsevier BV. - 0163-6383 .- 1879-0453. ; 34:2, s. 363-370
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Tidskriftsartikel (refereegranskat)abstract
- A conversation is made up of visual and auditory signals in a complex flow of events. What is the relative importance of these components for young children's ability to maintain attention on a conversation? In the present set of experiments the visual and auditory signals were disentangled in four filmed events. The visual events were either accompanied by the speech sounds of the conversation or by matched motor sounds and the auditory events by either the natural visual turn taking of the conversation or a matched turn taking of toy trucks. A cornea-reflection technique was used to record the gaze-pattern of subjects while they were looking at the films. Three age groups of typically developing children were studied; 6-month-olds, 1-year-olds and 3-year-olds. The results show that the children are more attracted by the social component of the conversation independent of the kind of sound used. Older children find spoken language more interesting than motor sound. Children look longer at the speaking agent when humans maintain the conversation. The study revealed that children are more attracted to the mouth than to the eyes area. The ability to make more predictive gaze shifts develops gradually over age.
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| 6. |
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| 7. |
- Bernspång, Birgitta, 1951-
(författare)
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Consequences of stroke : aspects of impairments, disabilities and life satisfaction : with special emphasis on perception and on occupational therapy
- 1987
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Perceptual and motor functions and self-care ability after stroke were assessed within two weeks (n:109; mean age 69±10) and 4-6 years (n:75;70±9) after admission to a non-intensive care stroke unit. Sixty-two of the long-term stroke survivors reported on their life satisfaction (7 items) as experienced (in retrospect) before the stroke and at the time of the investigation. Perceptual functions and actual levels of life satisfaction were registered in 60 clinically healthy subjects aged about 60 or about 80 years.Both early on and late after stroke the 16 items of perceptual function were clearly grouped into two factors, which neatly fitted an ecological perceptual concept. One factor characterized low-order and the other higher-order perception. Impairments of low-order perception occurred for about 10% of the patients, whether investigated early or late after stroke. No one among the reference populations had such impairments. Higher-order perceptual impairments prevailed in 60% early on and in 57% late after stroke and were often more pronounced than those occurring in the reference populations, among whom 35% of the 60 year olds and significantly more - 77% - of the 80 year olds had such impairments. Hence, perceptual impairments are common after stroke, but slight age-dependent reductions should be considered when higher-order perceptual function is assessed and treated after stroke.Together with motor function, which was impaired in 52% of the early and 36% of the late stroke samples, higher-order perceptual function and to a limited extent low-order perception could predict the level of self-care ability in 70% and 62% of the early and late samples, respectively.Whereas levels of global and of domain specific variables of life satisfaction were similar in the two reference populations, the stroke had lead to a reduction in life satisfaction for 61% of the long-term survivors. Reductions were particularly pronounced for global life satisfaction and for satisfaction with leisure and sexuality. Although significantly associated with motor impairment and self-care disability, these reductions could not be attributed only to impairments and disability.The findings are discussed with particular reference to assessment and treatment in occupational therapy.
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| 8. |
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| 9. |
- Brodd, Katarina Strand, et al.
(författare)
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Development of smooth pursuit eye movements in very preterm infants : 1. General aspects
- 2011
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 100:7, s. 983-991
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate early oculo-motor development in a population-based cohort of very preterm infants.Methods: Early oculo-motor development was prospectively studied by measuring smooth pursuit eye movements at 2 and 4 months corrected age in a population of very preterm infants born in Uppsala County 2004–2007. Eighty-one preterm infants were studied, and 32 healthy term infants constituted the control group.Results: The study group consisted of infants with a mean gestational age of28 + 5 weeks. At 2 and 4 months corrected age, infants born very preterm showed lower gain (p < 0.001) and proportion of smooth pursuit eyemovements (p < 0.001) compared to the control group. The boys showed higher gain of smooth pursuit eye movements at both 2 and 4 months corrected age, compared to girls.Conclusions: Oculo-motor development measured by smooth pursuit eye movements is delayed in very preterm infants at 2 and 4 months corrected age. This might be a risk factor or early indicator of later perceptual and behavioural impairment.
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| 10. |
- Bäckström, Anna, et al.
(författare)
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Action planning in relation to movement performance in 6-year-old children with autism spectrum disorder
- 2019
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Konferensbidrag (refereegranskat)abstract
- Introduction: Recent research proposes problems with action planning as part of atypical motor functioning in children with autism spectrum disorder (ASD), although findings are inconsistent. This study investigated relations between action planning and movement performance in 6-year-old children with and without ASD.Patients and methods: 3D kinematic recordings of preferred arm/hand performance on a sequential peg rotation task with varying complexity of goal insertion (four endpoints and either visual or occluded goal display at onset) were conducted in 6 children with ASD (MAge = 6.4) and 6 typically developing (TD) controls (MAge = 6.5).Results: Analyses revealed significant (p < .05) group and task-endpoint differences for movement segmentation (number of movement units, MUs) and 3D movement distance. Children with ASD generally displayed more MUs and longer distances than controls and all children showed increased MUs and movement distance on more complex task-endpoints. TD controls showed significantly shorter movement initiation latency (MIL) durations than ASD in the visual condition and evidently longer MILs in the occluded than visual condition. In contrast, no difference between goal display conditions was shown for the ASD group.Conclusion: Children with ASD generally had longer movement distances and more segmented movements than controls, suggesting less efficient movement performance. Movement performance was not evidently affected by goal display condition in either group. However, the lack of MIL differences between goal display conditions within the ASD group indicates reduced pre-planning, possibly affecting movement execution efficiency.
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