Psychologie
Refine
Year of publication
- 2018 (40) (remove)
Document Type
- Article (30)
- Book (3)
- Preprint (3)
- Master's Thesis (2)
- Conference Proceeding (1)
- Doctoral Thesis (1)
Has Fulltext
- yes (40)
Is part of the Bibliography
- no (40)
Keywords
- Depression (2)
- Experiment (2)
- Konstruktion (2)
- Language (2)
- Objektivität (2)
- Patients (2)
- Psychologie (2)
- Quality of life (2)
- Questionnaires (2)
- Science & Technology Studies (2)
Institute
Object recognition is such an everyday task it seems almost mundane. We look at the spaces around us and name things seemingly effortlessly. Yet understanding how the process of object recognition unfolds is a great challenge to vision science. Models derived from abstract stimuli have little predictive power for the way people explore "naturalistic" scenes and the objects in them. Naturalistic here refers to unaltered photographs of real scenes. This thesis therefore focusses on the process of recognition of the objects in such naturalistic scenes. People can, for instance, find objects in scenes much more efficiently than models derived from abstract stimuli would predict. To explain this kind of behavior, we describe scenes not solely in terms of physical characteristics (colors, contrasts, lines, orientations, etc.) but by the meaning of the whole scene (kitchen, street, bathroom, etc.) and of the objects within the scene (oven, fire hydrant, soap, etc.). Object recognition now refers to the process of the visual system assigning meaning to the object.
The relationship between objects in a naturalistic scene is far from random. Objects do not typically float in mid-air and cannot take up the same physical space. Moreover, certain scenes typically contain certain objects. A fire hydrant in the kitchen would seem like an anomaly to the average observer. These "rules" can be described as the "grammar" of the scene. Scene grammar is involved in multiple aspects of scene- and object perception. There is, for instance, evidence that overall scene category influences identification of individual objects. Typically, experiments that directly target object recognition do not involve eye movements and studies that involve eye movements are not directly aimed at object recognition, but at gaze allocation. But eye movements are abundant in everyday life, they happen roughly 4 times per second. Here we therefore present two studies that use eye movements to investigate when object recognition takes place while people move their eyes from object to object in a scene. The third study is aimed at the application of novel methods for analyzing data from combined eye movement and neurophysiology (EEG) measurements.
One way to study object perception is to violate the grammar of a scene by placing an object in a scene it does not typically occur in and measuring how long people look at the so-called semantic inconsistency, compared to an object that one would expect in the given scene. Typically, people look at semantic inconsistencies longer and more often, signaling that it requires extra processing. In Study 1 we make use of this behavior to ask whether object recognition still happens when it is not necessary for the task. We designed a search task that made it unnecessary to register object identities. Still, participants looked at the inconsistent objects longer than consistent objects, signaling they did indeed process object and scene identities. Interestingly, the inconsistent objects were not remembered better than the consistent ones. We conclude that object and scene identities (their semantics) are processed in an obligatory fashion; when people are involved in a task that does not require it. In Study 2, we investigate more closely when the first signs of object semantic processing are visible while people make eye movements.
Although the finding that semantic inconsistencies are looked at longer and more often has been replicated often, many of these replications look at gaze duration over a whole trial. The question when during a trial differences between consistencies occur, has yielded mixed results. Some studies only report effects of semantic consistency that accumulate over whole trials, whereas others report influences already on the duration of the very first fixations on inconsistent objects. In study 2 we argue that prior studies reporting first fixation duration may have suffered from methodological shortcomings, such as low trial- and sample sizes, in addition to the use of non-robust statistics and data descriptions. We show that a subset of fixations may be influenced more than others (as is indicated by more skewed fixation duration distributions). Further analyses show that the relationship between the effect of object semantics on fixation durations and its effect on oft replicated cumulative measures is not straightforward (fixation duration distributions do not predict dwell effects) but the effect on both measures may be related in a different way. Possibly, the processing of object meaning unfolds over multiple fixations, only when one fixation does not suffice. However, it would be very valuable to be able to study how processing continues, after a fixation ends.
Study 3 aims to make such a measure possible by combining EEG recordings with eye tracking measurements. Difficulties in analyzing eye tracking–EEG data exist because neural responses vary with different eye movements characteristics. Moreover, fixations follow one another in short succession, causing neural responses to each fixation to overlap in time. These issues make the well-established approach of averaging single trial EEG data into ERPs problematic. As an alternative, we propose the use of multiple regression, explicitly modelling both temporal overlap and eye movement parameters. In Study 3 we show that such a method successfully estimates the influence of covariates it is meant to control for. Moreover, we discuss and explore what additional covariates may be modeled and in what way, in order to obtain confound-free estimates of EEG differences between conditions. One important finding is that stimulus properties of physically variable stimuli such as complex scenes, can influence EEG signals and deserve close consideration during experimental design or modelling efforts. Overall, the method compares favorably to averaging methods.
From the studies in this thesis, we directly learn that object recognition is a process that happens in an obligatory fashion, when the task does not require it. We also learn that only a subset of first fixations to objects are affected by the processing of object meaning and its fit to its surroundings. Comparison between first fixation and first dwell effects suggest that, in active vision, object semantics processing sometimes unfolds over multiple fixations. And finally, we learn that regression-based methods for combined eye tracking-EEG analysis provide a plausible way forward for investigating how object recognition unfolds in active vision.
Although in real life people frequently perform visual search together, in lab experiments this social dimension is typically left out. Here, we investigate individual, collaborative and competitive visual search with visualization of search partners’ gaze. Participants were instructed to search a grid of Gabor patches while being eye tracked. For collaboration and competition, searchers were shown in real time at which element the paired searcher was looking. To promote collaboration or competition, points were rewarded or deducted for correct or incorrect answers. Early in collaboration trials, searchers rarely fixated the same elements. Reaction times of couples were roughly halved compared with individual search, although error rates did not increase. This indicates searchers formed an efficient collaboration strategy. Overlap, the proportion of dwells that landed on hexagons that the other searcher had already looked at, was lower than expected from simulated overlap of two searchers who are blind to the behavior of their partner. The proportion of overlapping dwells correlated positively with ratings of the quality of collaboration. During competition, overlap increased earlier in time, indicating that competitors divided space less efficiently. Analysis of the entropy of the dwell locations and scan paths revealed that in the competition condition, a less fixed looking pattern was exhibited than in the collaborate and individual search conditions. We conclude that participants can efficiently search together when provided only with information about their partner’s gaze position by dividing up the search space. Competing search exhibited more random gaze patterns, potentially reflecting increased interaction between searchers in this condition.
In transferring the concept of flow to the context of fiction reading a new approach to understanding the evolvement of reading pleasure is provided. This study presents the Reading Flow Short Scale (RFSS), the first reading-specific flow measurement tool. The RFSS was applied to 229 readers via online survey after 20 min of reading in self-selected novels. In a systematic analysis of psychometric properties, the RFSS’ factorial structure, reliability, and associations with theoretically related constructs were examined. As expected, the RFSS showed a two-factor structure, positive correlations with variables related to reading pleasure and flow, and an inverted U-shaped association with perceived fit between reader skills and text challenge. Comparisons of confirmatory factor analysis model confirmed that RFSS items loaded on different latent variables than items assessing other narrative engagement concepts, namely presence, identification, suspense, and cognitive mastery, and hence distinctly capture flow states in fiction reading. In sum, our findings indicate that the RFSS is a useful instrument for assessing flow states in fiction reading, thereby enriching the portfolio of measurement instruments in reading research.
An individualized and coherent life story has been described as the form of identity that is required by highly mobile individualistic Western societies, whereas more family-oriented, traditional societies require more role-based, synchronic identities. Therefore in individualistic cultures entire life narratives can be expected to be more coherent and to contain more autobiographical arguments that contribute to life narrative coherence. This cultural group difference is expected to be mediated by individuals’ conformity to their respective cultural normative concept of biography, such that more conformity leads to less life narrative coherence and fewer autobiographical arguments. We tested these expectations by eliciting entire life narratives and cultural life scripts from four different cultural groups of students of technical universities: from provincial Karabük and from metropolitan Istanbul in Turkey, as well as from students with a Turkish migrant and with a native German background from urban Frankfurt am Main, Germany (N = 96). Expectations were confirmed for global life narrative coherence and autobiographical arguments with self-event connections. Conformity with a normative concept of biography indeed partially mediated cultural influences on life narrative coherence. Life narratives from Turkey also contained more family-related events and, unexpectedly, were more negative. Thus creating a coherent life narrative is more typical for cultures that require autonomous, individualized selves rather than for cultures requiring more related selves, reflecting the life story’s suitability for expressing individualized identities and its lesser suitability for expressing interdependent identities.
Dreams and psychosis share several important features regarding symptoms and underlying neurobiology, which is helpful in constructing a testable model of, for example, schizophrenia and delirium. The purpose of the present communication is to discuss two major concepts in dreaming and psychosis that have received much attention in the recent literature: insight and dissociation. Both phenomena are considered functions of higher order consciousness because they involve metacognition in the form of reflective thought and attempted control of negative emotional impact. Insight in dreams is a core criterion for lucid dreams. Lucid dreams are usually accompanied by attempts to control the dream plot and dissociative elements akin to depersonalization and derealization. These concepts are also relevant in psychotic illness. Whereas insightfulness can be considered innocuous in lucid dreaming and even advantageous in psychosis, the concept of dissociation is still unresolved. The present review compares correlates and functions of insight and dissociation in lucid dreaming and psychosis. This is helpful in understanding the two concepts with regard to psychological function as well as neurophysiology.
Successful retrieval from memory is a desirably difficult learning event that reduces the recall decrement of studied materials over longer delays more than restudying does. The present study was the first to test this direct testing effect for performed and read action events (e.g., “light a candle”) in terms of both recall accuracy and recall speed. To this end, subjects initially encoded action phrases by either enacting them or reading them aloud (i.e., encoding type). After this initial study phase, they received two practice phases, in which the same number of action phrases were restudied or retrieval-practiced (Exp. 1–3), or not further processed (Exp. 3; i.e., practice type). This learning session was ensued by a final cued-recall test both after a short delay (2 min) and after a long delay (1 week: Exp. 1 and 2; 2 weeks: Exp. 3). To test the generality of the results, subjects retrieval practiced with either noun-cued recall of verbs (Exp. 1 and 3) or verb-cued recall of nouns (Exp. 2) during the intermediate and final tests (i.e., test type). We demonstrated direct benefits of testing on both recall accuracy and recall speed. Repeated retrieval practice, relative to repeated restudy and study-only practice, reduced the recall decrement over the long delay, and enhanced phrases’ recall speed already after 2 min, and this independently of type of encoding and recall test. However, a benefit of testing on long-term retention only emerged (Exp. 3), when prolonging the recall delay from 1 to 2 weeks, and using different sets of phrases for the immediate and delayed final tests. Thus, the direct testing benefit appears to be highly generalizable even with more complex, action-oriented stimulus materials, and encoding manipulations. We discuss these results in terms of the distribution-based bifurcation model.
Wie eine "Heilslehre" überzieht der Begriff "Digitalisierung" fast alle Lebensbereiche – natürlich auch den Bildungsbereich. Gerade wir Informatiker*innen sind gefordert, diese Wege der Bildungstransformation mitzugestalten. Wir zusammen mit den Erziehungswissenschaftler*innen und Psychologen*innen müssen identifizieren, aufzeigen und vorbildlich umsetzen, was sinnvoll und möglich ist. Wir sind diejenigen, die die Bedingungen des Gelingens und auch die der Irrwege erforschen und aufzeigen müssen. Digitalisierungswahnsinn brauchen wir nicht!
Die 16. Jahrestagung DeLFI 2018 der Fachgruppe eLearning der Gesellschaft für Informatik e. V. findet vom 10. bis 13.September 2018 an der Johann Wolfgang Goethe – Universität, Frankfurt am Main statt, gemeinsam mit der 8. Tagung für Hochschuldidaktik der Informatik HDI 2018. ...
Using the method or time-delayed embedding, a signal can be embedded into higher-dimensional space in order to study its dynamics. This requires knowledge of two parameters: The delay parameter τ, and the embedding dimension parameter D. Two standard methods to estimate these parameters in one-dimensional time series involve the inspection of the Average Mutual Information (AMI) function and the False Nearest Neighbor (FNN) function. In some contexts, however, such as phase-space reconstruction for Multidimensional Recurrence Quantification Analysis (MdRQA), the empirical time series that need to be embedded already possess a dimensionality higher than one. In the current article, we present extensions of the AMI and FNN functions for higher dimensional time series and their application to data from the Lorenz system coded in Matlab.