@phdthesis{Eidel2020,
  author    = {Eidel, Matthias T. A. M.},
  title     = {Training Effects of a Tactile Brain-Computer Interface System During Prolonged Use by Healthy And Motor-Impaired People},
  doi       = {10.25972/OPUS-20851},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-208511},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2020},
  abstract  = {Background - Brain-Computer Interfaces (BCI) enable their users to interact and communicate with the environment without requiring intact muscle control. To this end, brain activity is directly measured, digitized and interpreted by the computer. Thus, BCIs may be a valuable tool to assist severely or even completely paralysed patients. Many BCIs, however, rely on neurophysiological potentials evoked by visual stimulation, which can result in usability issues among patients with impaired vision or gaze control. Because of this, several non-visual BCI paradigms have been developed. Most notably, a recent study revealed promising results from a tactile BCI for wheelchair control. In this multi-session approach, healthy participants used the BCI to navigate a simulated wheelchair through a virtual apartment, which revealed not only that the BCI could be operated highly efficiently, but also that it could be trained over five sessions. The present thesis continues the research on this paradigm in order to - confirm its previously reported high performance levels and trainability - reveal the underlying factors responsible for observed performance increases - establish its feasibility among potential impaired end-users Methods - To approach these goals, three studies were conducted with both healthy participants and patients with amyotrophic lateral sclerosis (ALS). Brain activity during BCI operation was recorded via electroencephalography (EEG) and interpreted using a machine learning-based linear classifier. Wheelchair navigation was executed according to the classification results and visualized on a monitor. For offline statistical analysis, neurophysiological features were extracted from EEG data. Subjective data on usability were collected from all participants. Two specialized experiments were conducted to identify factors for training. Results and Discussion - Healthy participants: Results revealed positive effects of training on BCI performances and their underlying neurophysiological potentials. The paradigm was confirmed to be feasible and (for a non-visual BCI) highly efficient for most participants. However, some had to be excluded from analysis of the training effects because they could not achieve meaningful BCI control. Increased somatosensory sensitivity was identified as a possible mediator for training-related performance improvements. Participants with ALS: Out of seven patients with various stages of ALS, five could operate the BCI with accuracies significantly above chance level. Another ALS patient in a state of near-complete paralysis trained with the BCI for several months. Although no effects of training were observed, he was consistently able to operate the system above chance level. Subjective data regarding workload, satisfaction and other parameters were reported. Significance - The tactile BCI was evaluated on the example of wheelchair control. In the future, it could help impaired patients to regain some lost mobility and self-sufficiency. Further, it has the potential to be adapted to other purposes, including communication. Once visual BCIs and other assistive technologies fail for patients with (progressive) motor impairments, vision-independent paradigms such as the tactile BCI may be among the last remaining alternatives to interact with the environment. The present thesis has strongly confirmed the general feasibility of the tactile paradigm for healthy participants and provides first clues about the underlying factors of training. More importantly, the BCI was established among potential end-users with ALS, providing essential external validity.},
  subject      = {Myatrophische Lateralsklerose},
  language  = {en}
}
@phdthesis{Reinhard2019,
  author    = {Reinhard, Julia},
  title     = {Developmental Aspects of Fear Learning and Fear Generalization},
  doi       = {10.25972/OPUS-16437},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164372},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2019},
  abstract  = {In situations of real threat, showing a fear reaction makes sense, thus, increasing the chance to survive. The question is, how could anybody differentiate between a real and an apparent threat? Here, the slogan counts "better safe than sorry", meaning that it is better to shy away once too often from nothing than once too little from a real threat. Furthermore, in a complex environment it is adaptive to generalize from one threatening situation or stimulus to another similar situation/stimulus. But, the danger hereby is to generalize in a maladaptive manner involving as it is to strong and/or fear too often "harmless" (safety) situations/stimuli, as it is known to be a criterion of anxiety disorders (AD). Fear conditioning and fear generalization paradigms are well suited to investigate fear learning processes. It is remarkable that despite increasing interest in this topic there is only little research on fear generalization. Especially, most research on human fear conditioning and its generalization has focused on adults, whereas only little is known about these processes in children, even though AD is typically developing during childhood. To address this knowledge gap, four experiments were conducted, in which a discriminative fear conditioning and generalization paradigm was used. In the first two experiments, developmental aspects of fear learning and generalization were of special interest. Therefore, in the first experiment 267 children and 285 adults were compared in the differential fear conditioning paradigm and generalization test. Skin conductance responses (SCRs) and ratings of valence and arousal were obtained to indicate fear learning. Both groups displayed robust and similar differential conditioning on subjective and physiological levels. However, children showed heightened fear generalization compared to adults as indexed by higher arousal ratings and SCRs to the generalization stimuli. Results indicate overgeneralization of conditioned fear as a developmental correlate of fear learning. The developmental change from a shallow to a steeper generalization gradient is likely related to the maturation of brain structures that modulate efficient discrimination between threatening and (ambiguous) safety cues. The question hereby is, at which developmental stage fear generalization gradients of children adapt to the gradients of adults. Following up on this question, in a second experiment, developmental changes in fear conditioning and fear generalization between children and adolescents were investigated. According to experiment 1 and previous studies in children, which showed changes in fear learning with increasing age, it was assumed that older children were better at discriminating threat and safety stimuli. Therefore, 396 healthy participants (aged 8 to 12 years) were examined with the fear conditioning and generalization paradigm. Again, ratings of valence, arousal, and SCRs were obtained. SCRs indicated differences in fear generalization with best fear discrimination in 12-year-old children suggesting that the age of 12 years seems to play an important role, since generalization gradients were similar to that of adults. These age differences were seen in boys and girls, but best discrimination was found in 12-year-old boys, indicating different development of generalization gradients according to sex. This result fits nicely with the fact that the prevalence of AD is higher in women than in men. In a third study, it was supposed that the developmental trajectory from increased trait anxiety in childhood to manifest AD could be mediated by abnormal fear conditioning and generalization processes. To this end, 394 children aged 8 to 12 years with different scores in trait anxiety were compared with each other. Results provided evidence that children with high trait anxiety showed stronger responses to threat cues and impaired safety signal learning contingent on awareness as indicated by arousal at acquisition. Furthermore, analyses revealed that children with high trait anxiety showed overall higher arousal ratings at generalization. Contrary to what was expected, high trait anxious children did not show significantly more fear generalization than children with low trait anxiety. However, high-trait-anxious (HA) participants showed a trend for a more linear gradient, whereas moderate-trait-anxious (MA) and low-trait-anxious (LA) participants showed more quadratic gradients according to arousal. Additionally, after controlling for age, sex and negative life experience, SCR to the safety stimulus predicted the trait anxiety level of children suggesting that impaired safety signal learning may be a risk factor for the development of AD. Results provide hints that frontal maturation could develop differently according to trait anxiety resulting in different stimuli discrimination. Thus, in a fourth experiment, 40 typically developing volunteers aged 10 to 18 years were screened for trait anxiety and investigated with the differential fear conditioning and generalization paradigm in the scanner. Functional magnetic resonance imaging (fMRI) were used to identify the neural mechanisms of fear learning and fear generalization investigating differences in this neural mechanism according to trait anxiety, developmental aspects and sex. At acquisition, HA participants showed reduced activation in frontal brain regions, but at generalization, HA participants showed an increase in these frontal regions with stronger linear increase in activation with similarity to CS+ in HA when compared to LA participants. This indicates that there is a hyper-regulation in adolescents to compensate the higher difficulties at generalization in form of a compensatory mechanism, which decompensates with adulthood and/or may be collapsed in manifest AD. Additionally, significant developmental effects were found: the older the subjects the stronger the hippocampus and frontal activation with resemblance to CS+, which could explain the overgeneralization of younger children. Furthermore, there were differences according to sex: males showed stronger activation with resemblance to CS+ in the hippocampus and frontal regions when compared to females fitting again nicely with the observation that prevalence rates for AD are higher for females than males. In sum, the studies suggest that investigating developmental aspects of (maladaptive) overgeneralization may lead to better understanding of the mechanisms of manifest anxiety disorders, which could result in development and provision of prevention strategies. Although, there is need for further investigations, the present work gives some first hints for such approaches.},
  subject      = {Furcht},
  language  = {en}
}
@phdthesis{Holz2015,
  author    = {Holz, Elisa Mira},
  title     = {Systematic evaluation of non-invasive brain-computer interfaces as assistive devices for persons with severe motor impairment based on a user-centred approach - in controlled settings and independent use},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126334},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {Brain-computer interfaces (BCIs) are devices that translate signals from the brain into control commands for applications. Within the last twenty years, BCI applications have been developed for communication, environmental control, entertainment, and substitution of motor functions. Since BCIs provide muscle independent communication and control of the environment by circumventing motor pathways, they are considered as assistive technologies for persons with neurological and neurodegenerative diseases leading to motor paralysis, such as amyotrophic lateral sclerosis (ALS), muscular dystrophy, spinal muscular atrophy and stroke (K{\"u}bler, Kotchoubey, Kaiser, Wolpaw, \& Birbaumer, 2001). Although most researcher mention persons with severe motor impairment as target group for their BCI systems, most studies include healthy participants and studies including potential BCI end-users are sparse. Thus, there is a substantial lack of studies that investigate whether results obtained in healthy participants can be transferred to patients with neurodegenerative diseases. This clearly shows that BCI research faces a translational gap between intense BCI research and bringing BCI applications to end-users outside the lab (K{\"u}bler, Mattia, Rupp, \& Tangermann, 2013). Translational studies are needed that investigate whether BCIs can be successfully used by severely disabled end-users and whether those end-users would accept BCIs as assistive devices. Another obvious discrepancy exists between a plethora of short-term studies and a sparse number of long-term studies. BCI research thus also faces a reliability gap (K{\"u}bler, Mattia, et al., 2013). Most studies present only one BCI session, however the few studies that include several testing sessions indicate high inter- and intra-individual variance in the end-users' performance due to non-stationarity of signals. Long-term studies, however, are needed to demonstrate whether a BCI can be reliably used as assistive device over a longer period of time in the daily-life of a person. Therefore there is also a great need for reliability studies. The purpose of the present thesis was to address these research gaps and to bring BCIs closer to end-users in need, especially into their daily-lives, following a user-centred design (UCD). The UCD was suggested as theoretical framework for bringing BCIs to end-users by K{\"u}bler and colleagues (K{\"u}bler et al., 2014; Zickler et al., 2011). This approach aims at the close and iterative interaction between BCI developers and end-users with the final goal to develop BCI systems that are accepted as assistive devices by end-users. The UCD focuses on usability, that is, how well a BCI technology matches the purpose and meets the needs and requirements of the targeted end-users and was standardized with the ISO 9241-210. Within the UCD framework, usability of a device can be defined with regard to its effectiveness, efficiency and satisfaction. These aspects were operationalized by K{\"u}bler and colleagues to evaluate BCI-controlled applications. As suggested by Vaughan and colleagues, the number of BCI sessions, the total usage duration and the impact of the BCI on the life of the person can be considered as indicators of usefulness of the BCI in long-term daily-life use (Vaughan, Sellers, \& Wolpaw, 2012). These definitions and metrics for usability and usefulness were applied for evaluating BCI applications as assistive devices in controlled settings and independent use. Three different BCI applications were tested and evaluated by in total N=10 end-users: In study 1 a motor-imagery (MI) based BCI for gaming was tested by four end-users with severe motor impairment. In study 2, a hybrid P300 event-related (ERP) based BCI for communication was tested by four severely motor restricted end-users with severe motor impairment. Study 1 and 2 are short-term studies conducted in a controlled-setting. In study 3 a P300-ERP BCI for creative expression was installed for long-term independent use at the homes of two end-users in the locked-in state. Both end-users are artists who had gradually lost the ability to paint after being diagnosed with ALS. Results reveal that BCI controlled devices are accepted as assistive devices. Main obstacles for daily-life use were the not very aesthetic design of the EEG-cap and electrodes (cap is eye-catching and looks medical), low comfort (cables disturb, immobility, electrodes press against head if lying on a head cushion), complicated and time-consuming adjustment, low efficiency and low effectiveness, and not very high reliability (many influencing factors). While effectiveness and efficiency in the MI based BCI were lower compared to applications using the P300-ERP as input channel, the MI controlled gaming application was nevertheless better accepted by the end-users and end-users would rather like to use it compared to the communication applications. Thus, malfunctioning and errors, low speed, and the EEG cap are rather tolerated in gaming applications, compared to communication devices. Since communication is essential for daily-life, it has to be fast and reliable. BCIs for communication, at the current state of the art, are not considered competitive with other assistive devices, if other devices, such as eye-gaze, are still an option. However BCIs might be an option when controlling an application for entertainment in daily-life, if communication is still available. Results demonstrate that BCI is adopted in daily-life if it matches the end-users needs and requirements. Brain Painting serves as best representative, as it matches the artists' need for creative expression. Caveats such as uncomfortable cap, dependence on others for set-up, and experienced low control are tolerated and do not prevent BCI use on a daily basis. Also end-users in real need of means for communication, such as persons in the locked-in state with unreliable eye-movement or no means for independent communication, do accept obstacles of the BCI, as it is the last or only solution to communicate or control devices. Thus, these aspects are "no real obstacles" but rather "challenges" that do not prevent end-users to use the BCI in their daily-lives. For instance, one end-user, who uses a BCI in her daily-life, stated: "I don't care about aesthetic design of EEG cap and electrodes nor amplifier". Thus, the question is not which system is superior to the other, but which system is best for an individual user with specific symptoms, needs, requirements, existing assistive solutions, support by caregivers/family etc.; it is thereby a question of indication. These factors seem to be better "predictors" for adoption of a BCI in daily-life, than common usability criterions such as effectiveness or efficiency. The face valid measures of daily-life demonstrate that BCI-controlled applications can be used in daily-life for more than 3 years, with high satisfaction for the end-users, without experts being present and despite a decrease in the amplitude of the P300 signal. Brain Painting re-enabled both artists to be creatively active in their home environment and thus improved their feelings of happiness, usefulness, self-esteem, well-being, and consequently quality of life and supports social inclusion. This thesis suggests that BCIs are valuable tools for people in the locked-in state.},
  subject      = {Gehirn-Computer-Schnittstelle},
  language  = {en}
}
@phdthesis{Erlbeck2015,
  author    = {Erlbeck, Helena},
  title     = {The event-related potentials Mismatch Negativity, P300, and N400: Effects of attentional modulation and application in patients with disorders of consciousness},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121041},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {The present work comprises four studies dealing with the investigation of the auditory event-related potentials (ERP) Mismatch Negativity (MMN), P300, and N400 under different attentional instructions, and with their application in patients with disorders of consciousness (DOC) to assess residual cognitive functioning. In guided interviews (study 1), practitioners working with DOC patients stated their general interest in and an objective need for the complementation of current diagnostic procedures by reliable and valid ERP-based methods. Subsequently, in study 2, simple oddball and semantic paradigms were applied to 19 behaviorally non-responsive DOC patients revealing the presence of at least one ERP in eight patients investigated. In the third and fourth study, specific attentional effects on ERPs were investigated in healthy participants to define optimal instructions and stimulus parameters. In study 3, MMN and N400 amplitudes were assessed in 18 participants, and in study 4, MMN and P300 amplitudes were assessed in 32 participants. Both studies included an ignore task (attention on simultaneous visual stimuli), a passive task, and a focused task and revealed distinct attentional effects on P300 and N400 with largest amplitudes in the focused task, smaller ones in the passive task and no ERP in the ignore task. An MMN was elicited in all tasks, but still, amplitudes differed as a function of task. In addition, study 4 included oddball paradigms comprising several deviants in different dimensions. Higher amplitudes were found in this multifeature paradigm compared to traditional oddball paradigms and larger amplitudes were elicited by deviants highly different from standards. It is concluded that ERPs represent a promising tool to complement clinical assessment of DOC patients. Application of ERP paradigms should include focused instructions, especially when using semantic material. Furthermore, multifeature paradigms have been proven especially useful eliciting large amplitudes and allowing for the investigation of several dimensions of deviants at the same time.},
  subject      = {Bewusstseinsst{\"o}rung},
  language  = {en}
}
@phdthesis{Kaethner2015,
  author    = {K{\"a}thner, Ivo R. J.},
  title     = {Auditory and visual brain-computer interfaces as communication aids for persons with severe paralysis},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135477},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {Brain-computer interfaces (BCIs) could provide a muscle-independent communication channel to persons with severe paralysis by translating brain activity into device commands. As a means of communication, in particular BCIs based on event-related potentials (ERPs) as control signal have been researched. Most of these BCIs rely on visual stimulation and have been investigated with healthy participants in controlled laboratory environments. In proof-of-principle studies targeted end users gained control over BCI systems; however, these systems are not yet established as an assistive technology for persons who would most benefit from them. The main aim of this thesis is to advance the usability of ERP-BCIs for target users. To this end, five studies with BCIs have been conducted that enabled users to communicate by focusing their attention on external stimuli. Two studies were conducted in order to demonstrate the advantages and to further improve the practical application of visual BCIs. In the first study, mental workload was experimentally manipulated during prolonged BCI operation. The study showed the robustness of the visual ERP-BCI since users maintained a satisfactory level of control despite constant distraction in the form of background noise. Moreover, neurophysiological markers that could potentially serve as indicators of high mental workload or fatigue were revealed. This is a first step towards future applications in which the BCI could adapt to the mental state of the user (e.g. pauses if high mental workload is detected to prevent false selections). In the second study, a head-mounted display (HMD), which assures that stimuli are presented in the field of view of the user, was evaluated. High accuracies and information transfer rates, similar to a conventional display, were achieved by healthy participants during a spelling task. Furthermore, a person in the locked-in state (LIS) gained control over the BCI using the HMD. The HMD might be particularly suited for initial communication attempts with persons in the LIS in situations, where mounting a conventional monitor is difficult or not feasible. Visual ERP-BCIs could prove valuable for persons with residual control over eye muscles and sufficient vision. However, since a substantial number of target users have limited control over eye movements and/or visual impairments, BCIs based on non-visual modalities are required. Therefore, a main aspect of this thesis was to improve an auditory paradigm that should enable motor impaired users to spell by focusing attention on different tones. The two conducted studies revealed that healthy participants were able to achieve high spelling performance with the BCI already in the first session and stress the importance of the choice of the stimulus material. The employed natural tones resulted in an increase in performance compared to a previous study that used artificial tones as stimuli. Furthermore, three out of five users with a varying degree of motor impairments could gain control over the system within the five conducted sessions. Their performance increased significantly from the first to the fifth session - an effect not previously observed for visual ERP-BCIs. Hence, training is particularly important when testing auditory multiclass BCIs with potential users. A prerequisite for user satisfaction is that the BCI technology matches user requirements. In this context, it is important to compare BCIs with already established assistive technology. Thus, the fifth study of this dissertation evaluated gaze dependent methods (EOG, eye tracking) as possible control signals for assistive technology and a binary auditory BCI with a person in the locked-in state. The study participant gained control over all tested systems and rated the ease of use of the BCI as the highest among the tested alternatives, but also rated it as the most tiring due to the high amount of attention that was needed for a simple selection. Further efforts are necessary to simplify operation of the BCI. The involvement of end users in all steps of the design and development process of BCIs will increase the likelihood that they can eventually be used as assistive technology in daily life. The work presented in this thesis is a substantial contribution towards the goal of re-enabling communication to users who cannot rely on motor activity to convey their thoughts.},
  subject      = {Gehirn-Computer Schnittstelle},
  language  = {en}
}
@phdthesis{Real2015,
  author    = {Real, Ruben},
  title     = {Living with severe motor impairments - from consciousness to quality of life},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138562},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {The impact of acquired severe motor impairments is pervasive and may lead to a complete loss of communication and voluntary motor control, rendering the patient behaviourally unresponsive. In routine clinical care it may thus be unclear, whether some of these patients are even conscious. Given that finding a cure is unlikely, care focuses on providing the best possible quality of life (QoL), and knowing its predictors might contribute to that aim. Patients who still can communicate often report a high QoL, and several predictors have been identified. However, many instruments used to assess QoL require at least residual verbal and motor abilities. Thus, a method to assess QoL independent of these requirements is desirable. In addition, many instruments assume QoL to be temporarily stable, and little information is available on predictors of instantaneous QoL, i.e. QoL as it fluctuates from moment to moment throughout the day.},
  subject      = {Myatrophische Lateralsklerose},
  language  = {en}
}
@phdthesis{Kanis2016,
  author    = {Kanis, Julia Birgit},
  title     = {Elterliches Wissen, Selbsthilfe und psychotherapeutische Intervention bei nicht-organischen Schlafst{\"o}rungen im Kleinkindalter},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133432},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {F{\"u}r eine gesunde kindliche Entwicklung ist besonders in der fr{\"u}hen Kindheit guter Schlaf sehr wichtig. Gerade im Baby- und Kleinkindalter sind Schlafschwierigkeiten jedoch ein h{\"a}ufiges Ph{\"a}nomen. Vor allem Ein- und Durchschlafst{\"o}rungen kommen vielfach vor, die nicht automatisch mit zunehmendem Alter eines Kindes remittieren. Sie k{\"o}nnen persistieren und zum Teil auch schwerwiegende Folgen f{\"u}r die kindliche Entwicklung haben. Nicht nur Hyperaktivit{\"a}t, Reizbarkeit und Aggressivit{\"a}t treten bei Kindern mit Schlafst{\"o}rungen geh{\"a}uft auf, sondern auch Tagesm{\"u}digkeit, Konzentrationsund Ged{\"a}chtnisst{\"o}rungen sowie kognitive Beeintr{\"a}chtigungen k{\"o}nnen die Folge sein. Dar{\"u}ber hinaus k{\"o}nnen Depressionen, Angstst{\"o}rungen und {\"U}bergewicht langfristige Folgen von Schlafst{\"o}rungen sein. Auch wirken sich die Schlafst{\"o}rungen bei jungen Kindern negativ auf die Eltern aus. Daher ist es wichtig, Schlafprobleme im fr{\"u}hen Kindesalter zu erkennen, ernst zu nehmen und fr{\"u}hzeitig zu behandeln. Die vorliegende Arbeit besteht aus drei Teilen. Es wurden das elterliche Wissen {\"u}ber Schlaf im Kleinkindalter sowie eine Auswahl von Elternratgeberliteratur f{\"u}r kindliche Schlafprobleme untersucht. Ferner wurde das multimodale Elterntrainingsprogramm „Mini-KiSS", ein Elterntraining f{\"u}r Kinder bis vier Jahren mit Schlafst{\"o}rungen (Schlarb_2014), hinsichtlich seiner externen Validit{\"a}t betrachtet. Da Eltern diejenigen sind, die als erste mit den Schlafproblemen ihres Kindes konfrontiert sind, sollten sie kindliche Schlafst{\"o}rungen als diese erkennen und auch einsch{\"a}tzen k{\"o}nnen, um ggf. weiterf{\"u}hrende Maßnahme einzuleiten. Deshalb ist es wichtig, dass Eltern {\"u}ber den kindlichen Schlaf informiert sind. Um dieses elterliche Wissen {\"u}ber Schlaf von jungen Kindern zu erfassen, wurde ein Fragebogen entwickelt, in dem Anwendungs- und Faktenwissen {\"u}ber Schlaf im Baby- und Kleinkindalter erfragt wurden. Dieser wurde einer Online-Stichprobe (N = 1291) vorgelegt. Insgesamt verf{\"u}gten die Eltern {\"u}ber ein gutes Wissen, sie beantworteten 65\% der Fragen korrekt. Es zeigte sich jedoch ein Unterschied zwischen dem Anwendungswissen, wo die Eltern 72\% korrekt beantworteten und dem Faktenwissen, wo die Eltern 61\% der gestellten Fragen korrekt beantworteten. Allerdings wurden auch Unsicherheiten sowie Wissensdefizite deutlich, die noch genauer erfasst werden und denen k{\"u}nftig mit unverbindlichen Informations- und Beratungsangeboten begegnet werden sollte. Insbesondere bei den Interventionsm{\"o}glichkeiten zum Umgang mit einer Schlafproblematik im Kleinkindalter wurde ein Dissens deutlich, der sich auch in der nachfolgenden Analyse von Elternratgeberliteratur f{\"u}r Schlafschwierigkeiten widerspiegelte. Es wurden Literaturanalysen {\"u}ber Ratgeber f{\"u}r das Kindesalter einerseits und f{\"u}r das Baby- und Kleinkindalter andererseits durchgef{\"u}hrt. Dabei konnte gezeigt werden, dass die Autoren entweder eine Position zum lerntheoretischen Ansatz der graduierten Extinktion bezogen und diese Methode empfohlen oder das Co-Sleeping, also das gemeinsame Schlafen von Eltern und Kind in einem Bett, favorisierten. Zudem wurde in der vorliegenden Arbeit das multimodale Elterntraining Mini-KiSS bez{\"u}glich der externen Validit{\"a}t im Langzeitverlauf erfolgreich {\"u}berpr{\"u}ft. Das Elterntraining richtet sich an Eltern von Kindern im Alter von sechs Monaten bis vier Jahren mit Schlafst{\"o}rungen und findet in Form von sechs aufeinanderfolgenden Elternabenden statt. Durch das Training kam es zu signifikanten Verbesserungen des kindlichen und m{\"u}tterlichen Schlafes, diese bis zur Ein-Jahres-Katamnese stabil. Auch weitere mit problematischem kindlichem Schlafverhalten assoziierte Parameter, wie das allgemeine kindliche Problemverhalten sowie die elterliche Gesamtbelastung, konnten nachhaltig reduziert werden. Im Rahmen der vorliegenden Arbeit konnte gezeigt werden, dass sich die Intervention sowohl auf das Kind als auch auf die Eltern positiv auswirkte, was auch anhand von objektiven Verfahren best{\"a}tigt werden konnte. Zusammengefasst leistet diese Arbeit somit mit der Befragung einer großen Online-Stichprobe zu fr{\"u}hkindlichem Schlaf, der literaturanalytischen Betrachtung ausgew{\"a}hlter Ratgeberliteratur sowie der erfolgreichen Pr{\"u}fung der externen Validit{\"a}t des Mini-KiSS-Trainings einen wichtigen und richtungsweisenden Beitrag zur aktuellen Forschung im Bereich der nichtorganischen Schlafst{\"o}rungen im Kleinkindalter.},
  subject      = {Schlafst{\"o}rung},
  language  = {de}
}
@phdthesis{Herweg2016,
  author    = {Herweg, Andreas},
  title     = {Beyond the state of the art, towards intuitive and reliable non-visual Brain-Computer-Interfacing},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133447},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {For the present work three main goals were formulated: goal 1 To design a tactile BCI used for mobility which is intuitive (G1.1), reliable and fast while being usable by participants aged 50 years and above. goal 2 To design an auditory BCI used for communication which is intuitive and reliable. goal 3 To examine the effects of training on tactile and auditory BCI performance. Three studies were performed to achieve these goals. In the first study nine participants aged above 50 years performed a five-session training after which eight participants were able to navigate a virtual wheelchair with mean accuracy above 95\% and an ITR above 20 bits / min. In the second study 15 participants, four of them endusers with motor-impairment, were able to communicate meaningful with high accuracies using an auditory BCI. In the third study nine healthy and nine visually impaired participants (regarded as sensory experts for non-visual perception) performed tactile, auditory and visual (for healthy participants only) copy tasks. Participants with trained perception significantly outperformed control participants for tactile but not for auditory performance. Tactile performance of sensory experts was on equal levels as the visual performance of control participants. We were able to demonstrate viability of intuitive gazeindependent tactile and auditory BCI. Our tactile BCI performed on levels similar to those of visual BCI, outperforming current tactile BCI protocols. Furthermore, we were able to demonstrate significant beneficial effect of training on tactile BCI performance. Our results demonstrate previously untapped potential for tactile BCI and avenues for future research in the field of gaze-independent BCI.},
  subject      = {Gehirn-Computer-Schnittstelle},
  language  = {en}
}
@phdthesis{Sollfrank2015,
  author    = {Sollfrank, Teresa},
  title     = {Feedback efficiency and training effects during alpha band modulation over the sensorimotor cortex},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131769},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {Neural oscillations can be measured by electroencephalography (EEG) and these oscillations can be characterized by their frequency, amplitude and phase. The mechanistic properties of neural oscillations and their synchronization are able to explain various aspects of many cognitive functions such as motor control, memory, attention, information transfer across brain regions, segmentation of the sensory input and perception (Arnal and Giraud, 2012). The alpha band frequency is the dominant oscillation in the human brain. This oscillatory activity is found in the scalp EEG at frequencies around 8-13 Hz in all healthy adults (Makeig et al., 2002) and considerable interest has been generated in exploring EEG alpha oscillations with regard to their role in cognitive (Klimesch et al., 1993; Hanselmayr et al., 2005), sensorimotor (Birbaumer, 2006; Sauseng et al., 2009) and physiological (Lehmann, 1971; Niedermeyer, 1997; Kiyatkin, 2010) aspects of human life. The ability to voluntarily regulate the alpha amplitude can be learned with neurofeedback training and offers the possibility to control a brain-computer interface (BCI), a muscle independent interaction channel. BCI research is predominantly focused on the signal processing, the classification and the algorithms necessary to translate brain signals into control commands than on the person interacting with the technical system. The end-user must be properly trained to be able to successfully use the BCI and factors such as task instructions, training, and especially feedback can therefore play an important role in learning to control a BCI (Neumann and K{\"u}bler, 2003; Pfurtscheller et al., 2006, 2007; Allison and Neuper, 2010; Friedrich et al., 2012; Kaufmann et al., 2013; Lotte et al., 2013). The main purpose of this thesis was to investigate how end-users can efficiently be trained to perform alpha band modulation recorded over their sensorimotor cortex. The herein presented work comprises three studies with healthy participants and participants with schizophrenia focusing on the effects of feedback and training time on cortical activation patterns and performance. In the first study, the application of a realistic visual feedback to support end-users in developing a concrete feeling of kinesthetic motor imagery was tested in 2D and 3D visualization modality during a single training session. Participants were able to elicit the typical event-related desynchronisation responses over sensorimotor cortex in both conditions but the most significant decrease in the alpha band power was obtained following the three-dimensional realistic visualization. The second study strengthen the hypothesis that an enriched visual feedback with information about the quality of the input signal supports an easier approach for motor imagery based BCI control and can help to enhance performance. Significantly better performance levels were measurable during five online training sessions in the groups with enriched feedback as compared to a conventional simple visual feedback group, without significant differences in performance between the unimodal (visual) and multimodal (auditory-visual) feedback modality. Furthermore, the last study, in which people with schizophrenia participated in multiple sessions with simple feedback, demonstrated that these patients can learn to voluntarily regulate their alpha band. Compared to the healthy group they required longer training times and could not achieve performance levels as high as the control group. Nonetheless, alpha neurofeedback training lead to a constant increase of the alpha resting power across all 20 training session. To date only little is known about the effects of feedback and training time on BCI performance and cortical activation patterns. The presented work contributes to the evidence that healthy individuals can benefit from enriched feedback: A realistic presentation can support participants in getting a concrete feeling of motor imagery and enriched feedback, which instructs participants about the quality of their input signal can give support while learning to control the BCI. This thesis demonstrates that people with schizophrenia can learn to gain control of their alpha oscillations recorded over the sensorimotor cortex when participating in sufficient training sessions. In conclusion, this thesis improved current motor imagery BCI feedback protocols and enhanced our understanding of the interplay between feedback and BCI performance.},
  subject      = {Neurofeedback},
  language  = {en}
}
@phdthesis{Roeser2014,
  author    = {Roeser, Karolin},
  title     = {Nicht-organische Schlafst{\"o}rungen und deren Behandlung im Jugendalter - Externe Evaluation eines multimodalen Behandlungskonzepts f{\"u}r 11-17-J{\"a}hrige},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97445},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2014},
  abstract  = {H{\"a}ufige Schlafst{\"o}rungen im Jugendalter umfassen Ein- und Durchschlafprobleme (Insomnie), verst{\"a}rkte Tagesm{\"u}digkeit oder einen verschobenen Schlaf-Wachrhythmus (zirkadiane Rhythmusst{\"o}rung). {\"U}ber unzureichenden Schlaf klagen 40-60\% aller Jugendlichen, wobei ca. 10\% eine klinisch bedeutsame insomnische St{\"o}rung aufweisen. In der vorliegenden Arbeit wurde ein altersspezifisches, multimodales Gruppenpsychotherapieprogramm f{\"u}r Jugendliche (11-17 Jahre) mit nicht-organischen Schlafbeschwerden extern evaluiert. Das eingesetzte Training „JuSt" bestand aus 6 Sitzungen, wobei sich 5 Sitzungen an die Jugendlichen richteten und eine Sitzung als Elternabend stattfand. Zur {\"U}berpr{\"u}fung der Wirksamkeit des JuSt-Programms am Institut f{\"u}r Psychologie der Universit{\"a}t W{\"u}rzburg wurden schlafbezogene Parameter sowie Maße aus assoziierten Bereichen herangezogen. Zudem wurden Trainingseffekte auf den Schlaf und die psychische Belastung der Eltern untersucht. Die Erfassung dieser Ergebnisgr{\"o}ßen erfolgte sowohl vor und nach der Trainingsteilnahme als auch {\"u}ber einen Katamnesezeitraum von bis zu 12 Monaten. Daneben umfasste das Studiendesign eine Gruppe mit einer Wartephase vor Trainingsbeginn und die {\"U}berpr{\"u}fung m{\"o}glicher den Trainingserfolg moderierender Faktoren, wie Alter, Geschlecht und Chronotyp, d.h. zirkadiane Pr{\"a}ferenz, der Teilnehmer. Bereits nach dem diagnostischen Erstkontakt zeigte sich eine Abnahme selbstberichteter externalisierender und internalisierender Probleme bei den jugendlichen Teilnehmern in der Gruppe mit Wartephase (n = 9). Alle anderen Parameter blieben dagegen von der Wartezeit unber{\"u}hrt. Unmittelbar nach dem Training zeigten die Schlaftageb{\"u}cher der Teilnehmer (n = 22) ein verbessertes Durchschlafen und eine erh{\"o}hte Schlafeffizienz an. Fragebogendaten belegten zudem weniger selbst- und fremdberichtete Ein- und Durchschlafprobleme, seltenere dysfunktionale schlafbezogene Kognitionen, eine bessere Schlafhygiene und weniger Tagesm{\"u}digkeit in der Wahrnehmung der Eltern. Bis zur 3-Monatskatamnese hatten sich außerdem die Gesamtschlafdauer, die Einschlaflatenz und die selbstberichtete Tagesm{\"u}digkeit positiv ver{\"a}ndert. In den assoziierten Maßen zeigte sich ein unmittelbarer Trainingseffekt auf selbst- und fremdberichtete externalisierende Probleme sowie auf das Fremdurteil bez{\"u}glich internalisierender Probleme. Im Selbsturteil hatte sich dieses Maß erst zum 3-Monats Follow-Up verbessert. Auf Elternseite verringerten sich w{\"a}hrend der Trainingsdurchf{\"u}hrung die n{\"a}chtliche Aufwachh{\"a}ufigkeit der M{\"u}tter und die Schwere psychischer und somatischer Symptome beider Elternteile. Auf die Schlafeffizienz, die Dauer n{\"a}chtlichen Wachseins von V{\"a}tern und M{\"u}ttern sowie auf die n{\"a}chtliche Aufwachh{\"a}ufigkeit der V{\"a}ter hatte das Training eine verz{\"o}gerte positive Wirkung, da diese Effekte erst zum 3-Monats Follow-Up sichtbar wurden. Im Verlauf der Langzeitkatamnese (3-Monats- bis 1-Jahres Follow-Up, n = 16) blieben alle schlafbezogenen und assoziierten Ergebnisgr{\"o}ßen sowohl auf Kinder- als auch auf Elternseite auf konstantem Niveau. Dar{\"u}ber hinaus wurden explorativ die Merkmale Alter, Geschlecht und Chronotyp der Teilnehmer als m{\"o}gliche Moderatoren des Trainingserfolgs untersucht. Die Ergebnisse zeigten, dass der Trainingserfolg nicht an ein bestimmtes Geschlecht, ein bestimmtes Alter zwischen 11 und 17 Jahren oder einen bestimmten Chronotyp gebunden war. Insgesamt kann ein positives Fazit bez{\"u}glich der Wirksamkeit des JuSt-Programms zur Behandlung nicht-organischer Insomnien bei Jugendlichen und zur Entlastung ihrer Eltern am Standort W{\"u}rzburg gezogen werden. F{\"u}r die klinische Versorgung jugendlicher Insomniker wird angeregt, das JuSt-Training im deutschsprachigen Raum zuk{\"u}nftig verst{\"a}rkt in der therapeutischen Praxis zu implementieren.},
  subject      = {Schlafst{\"o}rung},
  language  = {de}
}
@phdthesis{Meule2014,
  author    = {Meule, Adrian},
  title     = {Food craving as a central construct in the self-regulation of eating behavior},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-104597},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2014},
  abstract  = {Background: Food craving refers to an intense desire to consume a specific kind of food of which chocolate is the most often craved one. It is this intensity and specificity that differentiates food craving from feelings of hunger. Although food craving and hunger often co-occur, an energy deficit is not a prerequisite for experiencing food craving, that is, it can also occur without being hungry. Food craving often precedes and predicts over- or binge eating which makes it a reasonable target in the treatment of eating disorders or obesity. One of the arguably most extensively validated measures for the assessment of food craving are the Food Cravings Questionnaires (FCQs), which measure food craving on a state (FCQ-S) and trait (FCQ-T) level. Specifically, the FCQ-S measures the intensity of current food craving whereas the FCQ-T measures the frequency of food craving experiences in general. The aims of the present thesis were to provide a German measure for the assessment of food craving and to investigate cognitive, behavioral, and physiological correlates of food craving. For this purpose, a German version of the FCQs was presented and its reliability and validity was evaluated. Using self-reports, relationships between trait food craving and dieting were examined. Cognitive-behavioral correlates of food craving were investigated using food-related tasks assessing executive functions. Psychophysiological correlates of food craving were investigated using event-related potentials (ERPs) in the electroencephalogram and heart rate variability (HRV). Possible intervention approaches to reduce food craving were derived from results of those studies. Methods: The FCQs were translated into German and their psychometric properties and correlates were investigated in a questionnaire-based study (articles \#1 \& \#2). The relationship between state and trait food craving with executive functioning was examined with behavioral tasks measuring working memory performance and behavioral inhibition which involved highly palatable food-cues (articles \#3 \& \#4). Electrophysiological correlates of food craving were tested with ERPs during a craving regulation task (article \#5). Finally, a pilot study on the effects of HRV-biofeedback for reducing food craving was conducted (article \#6). Results: The FCQs demonstrated high internal consistency while their factorial structure could only partially be replicated. The FCQ-T also had high retest-reliability which, expectedly, was lower for the FCQ-S. Validity of the FCQ-S was shown by positive relationships with current food deprivation and negative affect. Validity of the FCQ-T was shown by positive correlations with related constructs. Importantly, scores on the subscales of the FCQ-T were able to discriminate between non-dieters and successful and unsuccessful dieters (article \#1). Furthermore, scores on the FCQ-T mediated the relationship between rigid dietary control strategies and low dieting success (article \#2). With regard to executive functioning, high-calorie food-cues impaired working memory performance, yet this was independent of trait food craving and rarely related to state food craving (article \#3). Behavioral disinhibition in response to high-calorie food-cues was predicted by trait food craving, particularly when participants were also impulsive (article \#4). Downregulation of food craving by cognitive strategies in response to high-calorie food-cues increased early, but not later, segments of the Late Positive Potential (LPP) (article \#5). Few sessions of HRV-biofeedback reduced self-reported food cravings and eating and weight concerns in high trait food cravers (article \#6). Conclusions: The German FCQs represent sound measures with good psychometric properties for the assessment of state and trait food craving. Although state food craving increases during cognitive tasks involving highly palatable food-cues, impairment of task performance does not appear to be mediated by current food craving experiences. Instead, trait food craving is associated with low behavioral inhibition in response to high-calorie food-cues, but not with impaired working memory performance. Future studies need to examine if trait food craving and, subsequently, food-cue affected behavioral inhibition can be reduced by using food-related inhibition tasks as a training. Current food craving and ERPs in response to food-cues can easily be modulated by cognitive strategies, yet the LPP probably does not represent a direct index of food craving. Finally, HRV-biofeedback may be a useful add-on element in the treatment of disorders in which food cravings are elevated. To conclude, the current thesis provided measures for the assessment of food craving in German and showed differential relationships between state and trait food craving with self-reported dieting behavior, food-cue affected executive functioning, ERPs and HRV-biofeedback. These results provide promising starting points for interventions to reduce food craving based on (1) food-cue-related behavioral trainings of executive functions, (2) cognitive craving regulation strategies, and (3) physiological parameters such as HRV-biofeedback.},
  subject      = {Craving},
  language  = {en}
}
@phdthesis{Botrel2018,
  author    = {Botrel, Loic},
  title     = {Brain-computer interfaces (BCIs) based on sensorimotor rhythms - Evaluating practical interventions to improve their performance and reduce BCI inefficiency},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-168110},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2018},
  abstract  = {Brain computer interfaces based on sensorimotor rhythms modulation (SMR-BCIs) allow people to emit commands to an interface by imagining right hand, left hand or feet movements. The neurophysiological activation associated with those specific mental imageries can be measured by electroencephalography and detected by machine learning algorithms. Improvements for SMR-BCI accuracy in the last 30 years seem to have reached a limit. The currrent main issue with SMR-BCIs is that between 15\% to 30\% cannot use the BCI, called the "BCI inefficiency" issue. Alternatively to hardware and software improvements, investigating the individual characteristics of the BCI users has became an interesting approach to overcome BCI inefficiency. In this dissertation, I reviewed existing literature concerning the individual sources of variation in SMR-BCI accuracy and identified generic individual characteristics. In the empirical investigation, attention and motor dexterity predictors for SMR-BCI performance were implemented into a trainings that would manipulate those predictors and lead to higher SMR-BCI accuracy. Those predictors were identified by Hammer et al. (2012) as the ability to concentrate (associated with relaxation levels) and "mean error duration" in a two-hand visuo-motor coordination task (VMC). Prior to a SMR-BCI session, a total of n=154 participants in two locations took part of 23 min sessions of either Jacobson's Progressive Muscle Relaxation session (PMR), a VMC session, or a control group (CG). No effect of PMR or VMC manipulation was found, but the manipulation checks did not consistently confirm whether PMR had an effect of relaxation levels and VMC on "mean error duration". In this first study, correlations between relaxation levels or "mean error duration" and accuracy were found but not in both locations. A second study, involving n=39 participants intensified the training in four sessions on four consecutive days or either PMR, VMC or CG. The effect or manipulation was assessed for in terms of a causal relationship by using a PRE-POST study design. The manipulation checks of this second study validated the positive effect of training on both relaxation and "mean error duration". But the manipulation did not yield a specific effect on BCI accuracy. The predictors were not found again, displaying the instability of relaxation levels and "mean error duration" in being associated with BCI performance. An effect of time on BCI accuracy was found, and a correlation between State Mindfulness Scale and accuracy were reported. Results indicated that a short training of PMR or VMC were insufficient in increasing SMR-BCI accuracy. This study contrasted with studies succeeding in increasing SMR-BCI accuracy Tan et al. (2009, 2014), by the shortness of its training and the relaxation training that did not include mindfulness. It also contrasted by its manipulation checks and its comprehensive experimental approach that attempted to replicate existing predictors or correlates for SMR-BCI accuracy. The prediction of BCI accuracy by individual characteristics is receiving increased attention, but requires replication studies and a comprehensive approach, to contribute to the growing base of evidence of predictors for SMR-BCI accuracy. While short PMR and VMC trainings could not yield an effect on BCI performance, mindfulness meditation training might be beneficial for SMR-BCI accuracy. Moreover, it could be implemented for people in the locked-in-syndrome, allowing to reach the end-users that are the most in need for improvements in BCI performance.},
  subject      = {Gehirn-Computer-Schnittstelle},
  language  = {en}
}
@phdthesis{Zetzl2021,
  author    = {Zetzl, Teresa Margarete},
  title     = {Cancer-related fatigue intervention},
  doi       = {10.25972/OPUS-25166},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-251662},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2021},
  abstract  = {The incidence of cancer cases is rising steadily, while improved early detection and new cancer-specific therapies are reducing the mortality rate. In addition to curing cancer or prolonging life, increasing the quality of life is thus an important goal of oncology, which is why the burdens of cancer and treatment are becoming more important. A common side effect of cancer and its therapy is cancer-related fatigue, a tiredness that manifests itself on physical, emotional and cognitive levels and is not in proportion to previous physical efforts. Since the etiology of fatigue has not yet been fully clarified, symptom-oriented therapy is preferable to cause-specific therapy. In addition to activity management, sleep hygiene, and cognitive behavioral therapy, mind-body interventions such as yoga are recommended for reducing fatigue. Previous studies with small sample sizes were able to examine the efficacy of yoga regarding fatigue predominantly in patients with breast cancer. Long-term effects of yoga have rarely been studied and there have been no attempts to increase long-term effects through interventions such as reminder e-mails. This dissertation takes a closer look at these mentioned aspects of the study sample and long-term effects. An 8-week randomized controlled yoga intervention was conducted, including patients with different cancer types reporting mild to severe fatigue. Following the 8-week yoga therapy, a randomized group of participants received weekly reminder e-mails for 6 months for regular yoga practice, whereas the control group did not receive reminder e-mails. The first paper is a protocol article, which addresses the design and planned implementation of the research project this dissertation is based upon. This serves to ensure better replicability and comparability with other yoga studies. Due to a very low consent rate of patients in the pilot phase, it was necessary to deviate from the protocol article in the actual implementation and the planned inclusion criterion of fatigue >5 was reduced to fatigue >1. The second paper examines the efficacy of the eight-week yoga intervention. Patients in the intervention group who participated in the yoga classes seven times or more showed a significantly greater reduction in general and physical fatigue than those who participated less often. The efficacy of yoga was related to the number of attended yoga sessions. Women with breast cancer who participated in yoga reported greater reductions in fatigue than women with other cancer types. There was also an improvement for depression and quality of life after eight weeks of yoga therapy compared to no yoga therapy. These results imply that yoga is helpful in reducing depression and cancer-related fatigue, especially in terms of physical aspects and improving quality of life. The third paper focuses on the efficacy of reminder e-mails in terms of fatigue and practice frequency. Patients who received reminder e-mails reported greater reductions in general and emotional fatigue, as well as significant increases in practice frequency, compared to patients who did not receive reminder e-mails. Compared to fatigue scores before yoga, significantly lower fatigue and depression scores and higher quality of life were reported after yoga therapy and at follow-up six months later. Weekly e-mail reminders after yoga therapy may have positive effects on general and emotional fatigue and help cancer patients with fatigue establish a regular yoga practice at home. However, higher practice frequency did not lead to higher improvement in physical fatigue as found in Paper 2. This may indicate other factors that influence the efficacy of yoga practice on physical fatigue, such as mindfulness or side effects of therapy. This research project provides insight into the efficacy of yoga therapy for oncology patients with fatigue. It is important that such interventions be offered early, while fatigue symptoms are not too severe. Regular guided yoga practice can reduce physical fatigue, but subsequent yoga practice at home does not further reduce physical fatigue. Reminder emails after completed yoga therapy could only reduce patients' emotional fatigue. It may be that physical fatigue was reduced as much as possible by the previous yoga therapy and that there was a floor effect, or it may be that reminder emails are not suitable as an intervention to reduce physical fatigue at all. Further research is needed to examine the mechanisms of the different interventions in more detail and to find appropriate interventions that reduce all levels of fatigue equally.},
  subject      = {Erm{\"u}dungssyndrom},
  language  = {en}
}
@phdthesis{Leinfelder2022,
  author    = {Leinfelder, Teresa},
  title     = {Untersuchung von Trainingseffekten bei der Verwendung einer auditorischen P300-basierten EEG Gehirn-Computer Schnittstelle mittels fMRI Analyse},
  doi       = {10.25972/OPUS-29068},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-290683},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {In dieser Dissertation untersuchten wir die neuronalen Korrelate des Training-Effektes einer auditorischen P300 Gehirn-Computer Schnittstelle mittels fMRI Analyse in einem pr{\"a}-post Design mit zehn gesunden Testpersonen. Wir wiesen in drei Trainings-sitzungen einen Trainingseffekt in der EEG-Analyse der P300 Welle nach und fanden entsprechende Kontraste in einer pr{\"a}-post Analyse von fMRI Daten, wobei in allen f{\"u}nf Sitzungen das gleiche Paradigma verwendet wurde. In der fMRI Analyse fanden wir fol-gende Ergebnisse: in einem Target-/ Nichttarget Kontrast zeigte sich verst{\"a}rkte Aktivie-rung in Generatorregionen der P300 Welle (temporale und inferiore frontale Regionen) und interessanterweise auch in motorassoziierten Arealen, was h{\"o}here kognitiver Pro-zesse wie Aufmerksamkeitslenkung und Arbeitsspeicher widerspiegeln k{\"o}nnte. Der Kon-trast des Trainingseffektes zeigte nach dem Training einen st{\"a}rkeren Rebound Effekt im Sinne einer verst{\"a}rkten Aktivierung in Generatorregionen der P300 Welle, was eine ver-besserte Erkennung und Prozessierung von Target-Stimuli reflektieren k{\"o}nnte. Eine Ab-nahme von Aktivierung in frontalen Arealen in diesem Kontrast k{\"o}nnte durch effizientere Abl{\"a}ufe kognitiver Prozesse und des Arbeitsged{\"a}chtnis erkl{\"a}rt werden.},
  subject      = {Gehirn-Computer-Schnittstelle},
  language  = {de}
}