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- Feng, Qi, 1961-
(författare)
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Predictive action in infancy : Evidence of early prospective behavior
- 2009
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- How do young infants understand and act on their constantly changing environment? An action perspective on motor development was taken into account. The present thesis investigated perception guided predictive action in 6-month-old infants, namely, head tracking and reaching for an object moving on a pre-defined trajectory, linear or nonlinear, fully visible or partially occluded. The motion trials were presented in a randomized order or in a way by using an ABBA block design. Study I of this thesis began with the exploration of the principles underlying infant predictive action. Infants were presented a fully visible moving object on four trajectories: two linear trajectories that intersected at the center of a display and two non-linear trajectories that contained a sudden turn at the point of intersection. The results supplied evidence that both infants’ head tracking and reaching showed an extrapolation of the object’s motion on linear paths, which was described by the principle of inertia. No learning effect was found in spite of repeated fully visible trials. Previous experiments reported that infants of similar age showed a reduction in reaching when object motion was occluded briefly. Thus Study II was undertaken, in part, to evaluate whether differences in the tasks resented to infants or differences in the visibility of the objects account for these findings. This was done by investigating infants’ predictive head tracking of an object following the procedure presented in Study I with only one exception: object motion was partially occluded by a small occluder positioned on the motion trajectory. Study II also raised a second question concerning infants’ ability to learn to anticipate upcoming object motions. It was found that infants were able to quickly learn to anticipate either linear or nonlinear motion but with a superior learning effect from linear motion. This pattern suggested a tendency to anticipate the upcoming motion in accord with inertia. Although a capacity to anticipate occluded object motion in accord with inertia was present, it was weak, as infants’ initial reaction to the occluded object motion revealed no such tendency. Learning in all cases was associated with the trajectory of the object, not the specific locations at which the object appeared. It was suggested that infants might form object representations that are influenced by learning and that are just weakly biased toward inertia extrapolation. This finding supported the claims that occlusion reduces the presentation of object representation, as suggested by single system of object representation theory.
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| 2. |
- Ljung Aust, Mikael, 1973
(författare)
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Developing Theoretical and Empirical Definitions of Safety Problems in Driving Suitable for Active Safety Function Evaluation
- 2009
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In passive safety, the requirement specifications used for evaluation of protective functions are both standardised and specified at a high level of detail regarding evaluation scenario definition, performance metrics and pass/fail criteria. For active safety, while several propositions for evaluation scenarios have been made, neither these, nor performance metrics and pass/fail criteria have yet reached a similar level of detail and standardisation. The objective of this thesis is to address two underlying reasons for this difference. One is theoretical in nature. On a general level, a set of principles and concepts which capture the fundamental ideas of a field of science can be called a conceptual framework. For active safety function evaluation, such a framework is currently lacking. To address this issue, a conceptual framework called Situational control was developed. The framework integrates fundamental ideas relevant for active safety function evaluation into a holistic and practically applicable picture. Its applicability was demonstrated by applying it in the context of writing and implementing requirement specifications for active safety function evaluation.The second reason is of empirical character. To evaluate the extent to which active safety functions prevent and/or mitigate crashes, it is essential to characterize the sequence of events which leads to collisions in a way which includes information on causal factors. To do this, data from official databases (macroscopic data), and in-depth case studies is often used. Macroscopic data is usually statistically representative but has limited information on why crashes happen, while the opposite is true of case studies. Using the two in combination would therefore seem ideal. However, the principles for connecting them are far from clear and current approaches suffer inherent weaknesses. To address this issue, a generalization methodology which links information in case studies to macroscopic crash types, in a way which covers not only context but also causation similarity, was developed. The feasibility of the methodology was tested through application on three sets of intersection crash data. Results indicate that the methodology was sufficiently successful to warrant further exploration with larger data sets.
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| 3. |
- Kajonius, Petri, 1974-
(författare)
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The Impact of Care Process on Satisfaction with Elderly Care
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This licentiate thesis is based on the growing interest in Swedish elderly care. The aim of this thesis is to investigate what generates satisfaction with elderly care among older persons. The dominant ideology in both privately and publically run elderly care is individualized care, also called person-centered care, which holds the older person’s satisfaction as one of the main quality indicators. The proportion of older people is increasing and to maintain high levels of satisfaction with elderly care will require more knowledge. Data from the National Board of Health and Welfare’s (2012) nationwide survey on seniors’ experiences with elderly care was collected. Statistical analyses of this sample formed the basis for the results of the thesis and were reported in two papers. Study I used Donabedian’s (1988) model of quality of care in terms of structure, process, and outcome, and all municipal units in Sweden were included (N = 324). The results showed that structural variables (i.e. budget, staff, and training level) have minimal or no relationships with older persons’ satisfaction with care, while process variables (i.e. experiences of respect, information, and influence) have strong relationships with satisfaction with care. Study II made use of the long-standing person versus situation- model in social psychology, and was analyzed on an individual level (N = 95,000). The results showed that care process factors (i.e. experiences of treatment, safeness, staff- and time-availability) had a stronger relationship, than individual factors (i.e. health, anxiety, and loneliness) with satisfaction with care. The results also showed that older persons with home care generally felt better treated than older persons in nursing homes, but also felt less safe. Mediational analyses, based on this comprehensive elderly data, suggest that the individual aging condition of loneliness can be countered by providing safeness and treatment, resulting in high satisfaction with care. In conclusion, satisfaction with elderly care in Sweden today can largely be explained from a psychological perspective by the older persons’ perception of the care process, not by the amount of structural resources or the conditions of the aging persons. These findings could help facilitate the future quality development in municipalities and care organizations.
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| 4. |
- Andersson, Pehr
(författare)
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THE ROLE OF VISUAL-SPATIAL ABILITY AND WORKING MEMORY IN IMAGE GUIDED SIMULATOR PERFORMANCE
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Numerous studies have analyzed the critical factors for training in surgical endoscopy to ensure high performance and increased patient safety. There are, however, surprisingly few studies that focus on the role of cognitive abilities, especially considering the fact that an estimated 50% of allmedical errors that lead to permanent disability and death are the result of cognitive failures (Gawande, Zinner, Studdert & Biennen, 2003). This thesis provides initial outlines of two cognitive abilities that may underlie endoscopic simulator performance. In study 1 we addressed how high-level visual-spatial ability of surgical novices is related to performance of two simulatortasks with and without anatomical graphics and haptic feedback, differing in visual-spatial complexity. In study 2 we investigated whether visual and verbal working memory are related to the outcome of task performance scores in simulated laparoscopic cholecystectomy and gastroscopy training. Taken together, the results suggest that visual-spatial ability and working memory are significantly related to endoscopic simulator performance scores and that anincreased cognitive workload enhances the individual differences found. These findings can be used to better implement endoscopic surgical curriculum since novice trainees can be identified early and they might benefit from supplementary education in specific surgical tasks.
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| 5. |
- Domellöf, Erik, 1970-
(författare)
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Stepping, placing and headturning biases in newborn infants : A neurodevelopmental perspective
- 2004
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In the present thesis the stepping, placing and head turning responses in healthy humanfullterm newborns are investigated. The main focus is put on a study of these newbornresponses in relation to functional asymmetries, while at the same time exploring anddiscussing different factors that possibly can affect the outcome of such studies. Study I aims to examine one such factor in relation to underlying mechanisms controlling leg movements in focusing on the effects of glucose on newborn stepping and placing responses. The results revealed that glucose, as well as an inactive state, resulted in less pronounced stepping responses and difficulties in eliciting them. There was also a tendency towards a similar finding for placing in that both glucose and an inactive state were associated with a less vigorous placing response, although this could not be proved significant. However, there was no effect of glucose on expressions of laterality in either ofthe responses studied. A theoretical debate in progress concerns whether different newborn functional asymmetries can be said representing a single neural system for lateralization or multiple sub-systems rooted in different neural mechanisms (Grattan, De Vos, Levy, & McClintock, 1992). In order to look closer at this issue in relation to newborn head- and leg preferences, Study II was designed to investigate the presence of side biases in newbornstepping and placing responses (lower-body), together with head turning preference (upperbody), and whether observed lateral biases of the upper- and lower body are congruent with each other. No evident lateral bias could be found for either response in terms of the first foot moved or direction of head turning. Furthermore, asymmetries in head turning did not correspond to asymmetries in leg movements, in support for multiple sub-systemsrather than a single lateralized system. However, a lateral bias was found for onset latency in relation to the first foot moved in both stepping and placing. The findings 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.
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| 6. |
- Eriksson, Johan
(författare)
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Neuroimaging Consciousness: What happens in the brain when we become aware of what we percieve?
- 2004
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Although consciousness has been studied since the beginning of the history of psychology, how the brain implements consciousness is seen as one of the last great mysteries. This thesis investigates neural correlates of consciousness by measuring brain activity while specific contents of consciousness are defined and maintained. Study 1 showed that distinct but similar brain regions are activated for the initial creation of a percept and for sustaining that percept over time. Specifically, frontal and parietal regions were activated during both temporal aspects of consciousness. Study 2 investigated the generality of this activation pattern for consciousness in different sensory modalities, and showed that frontal regions were commonly activated for visual and auditory awareness whereas posterior activity was modality specific. However, frontal andparietal regions were jointly activated for both modalities during sustained perception. These results indicate that frontal regions interact with posterior, sensory-specific regions to instantiate a conscious percept. The percept is then maintained by a more general network including frontal and parietal regions.
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| 7. |
- Gurdal, Sevtap, 1976-
(författare)
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Parenting Across Cultures : Parental attributions, attitudes and behaviour
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Previously studies in parenting have mainly been conducted in Western countries. Not uncommonly results from such studies are used to describe general, worldwide trends. In an attempt to make the field of parenting research more culturally heterogeneous, an international research project, Parenting Across Cultures, was started. The project includes nine participant countries (China, Colombia, Italy, Jordan, Kenya, Philippines, Sweden, Thailand, and USA) and its purpose is to examine parenting across cultures. This thesis is based on reports from parent participants. The aim of Study I was to investigate mothers’ and fathers’ (77 participants from each group) attributions and attitudes in Sweden. The results revealed that Swedish parents are more polarized in their attitudes than in their attributions, they think more alike for parenting attitudes and there was greater variability for parenting attributions, particularly regarding uncontrollable success, as opposed to attributions regarding adult- or child-controlled failure. Regarding attitudes, mothers and fathers reported more progressive than authoritarian attitudes. Fathers reported higher adult-controlled failure and child-controlled failure attributions than mothers. In Study II the aim was to assess whether mothers’ and fathers’ self-reports of acceptance-rejection, warmth, and hostility/rejection/neglect of their children differ in the nine countries. A total of 1996 parents (998 mothers and 998 fathers) participated in the study. Mothers and fathers reported high acceptance and warmth and low rejection and hostility/rejection/neglect (HRN) of their children in all nine countries. Despite the overwhelmingly high levels of acceptance and low levels of rejection across all countries, and despite our use of statistical controls for parental age, education, social desirability, and child age, some systematic differences between countries emerged. In summary, parents in the studies report higher similarity about parenting in some cases, for example concerning acceptance and warmth and hostility/rejection/neglect, but lower in others, such as the Swedish parents’ reports about attributions.
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| 8. |
- Hansson, Patrik
(författare)
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Overconfidence and Format Dependence in Subjective Probability Intervals: Naive Estimation and Constrained Sampling
- 2005
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A particular field in research on judgment and decision making (JDM) is concerned with realism of confidence in one’s knowledge. An interesting finding is the so-called format dependence effect which implies that assessment of the same probability distribution generates different conclusions about over- or underconfidence bias depending on the assessment format. In particular,expressing a belief about some unknown quantity in the form of a confidence interval is severely prone to overconfidence as compared to expressing the belief as an assessment of a probability. This thesis gives a tentative account of this finding in terms of a Naïve Sampling Model (NSM;Juslin, Winman, & Hansson, 2004), which assumes that people accurately describe their available information stored in memory but they are naïve in the sense that they treat sample properties as proper estimators of population properties. The NSM predicts that it should be possible to reducethe overconfidence in interval production by changing the response format into interval evaluation and to manipulate the degree of format dependence between interval production and interval evaluation. These predictions are verified in empirical experiments which contain both general knowledge tasks (Study 1) and laboratory learning tasks (Study 2). A bold hypothesis,that working memory is a constraining factor for sample size in judgment which suggests that experience per se does not eliminate overconfidence, is investigated and verified. The NSM predicts that the absolute error of the placement of the interval is a constant fraction of interval size, a prediction that is verified (Study 2). This thesis suggests that no cognitive processing bias(Tversky & Kahneman, 1974) over and above naivety is needed to understand and explain the overconfidence bias in interval production and hence the format dependence effect.
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| 9. |
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| 10. |
- Holm, Linus
(författare)
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Gaze control in episodic memory
- 2004
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The role of gaze control in episodic recognition was investigated in two studies. In Study 1, participants encoded human faces inverted or upright, with or without eye movements (Experiment 1) and under sorting or rating tasks (Experiment 2) respectively. At test, participants indicated their recollective experience with R(emember) responses (explicit recollection) orK(now) responses (familiarity based recognition). Experiment 1 showed that face inversion and occlusion of eye movements reduced levels of explicit recollection as measured by R responses. In Experiment 2, the relation between recollective experience and perceptual reinstatement wasexamined. Whereas the study instructions produced no differences in terms of eye movements, R responses were associated with a higher proportion of refixations than K responses.In Study 2, perceptual consistency was investigated in two experiments. In Experiment 1, participants studied scenes under different concurrent tasks. Subsequently, their recognition memory was examined in a R / K test. Executive load produced parallel effects on eye movements and R responses. Furthermore, R responses were associated with a higher proportion ofrefixations than K responses. However, number of fixations was correlated with refixations.Experiment 2 corroborated these results and controlled for number of fixations.Together, these studies suggest that visual episodic representations are supported by perceptual detail, and that explicit recollection is a function of encoding and retrieving those details. To this end, active gaze control is an important factor in visual recognition.
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