@phdthesis{LopezGambino2023,
  author    = {L{\´o}pez Gambino, Maria Soledad},
  title     = {Time Buying in Task-Oriented Spoken Dialogue Systems},
  doi       = {10.25932/publishup-59280},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-592806},
  school      = {Universit{\"a}t Potsdam},
  pages     = {148},
  year      = {2023},
  abstract  = {This dissertation focuses on the handling of time in dialogue. Specifically, it investigates how humans bridge time, or "buy time", when they are expected to convey information that is not yet available to them (e.g. a travel agent searching for a flight in a long list while the customer is on the line, waiting). It also explores the feasibility of modeling such time-bridging behavior in spoken dialogue systems, and it examines how endowing such systems with more human-like time-bridging capabilities may affect humans' perception of them. The relevance of time-bridging in human-human dialogue seems to stem largely from a need to avoid lengthy pauses, as these may cause both confusion and discomfort among the participants of a conversation (Levinson, 1983; Lundholm Fors, 2015). However, this avoidance of prolonged silence is at odds with the incremental nature of speech production in dialogue (Schlangen and Skantze, 2011): Speakers often start to verbalize their contribution before it is fully formulated, and sometimes even before they possess the information they need to provide, which may result in them running out of content mid-turn. In this work, we elicit conversational data from humans, to learn how they avoid being silent while they search for information to convey to their interlocutor. We identify commonalities in the types of resources employed by different speakers, and we propose a classification scheme. We explore ways of modeling human time-buying behavior computationally, and we evaluate the effect on human listeners of embedding this behavior in a spoken dialogue system. Our results suggest that a system using conversational speech to bridge time while searching for information to convey (as humans do) can provide a better experience in several respects than one which remains silent for a long period of time. However, not all speech serves this purpose equally: Our experiments also show that a system whose time-buying behavior is more varied (i.e. which exploits several categories from the classification scheme we developed and samples them based on information from human data) can prevent overestimation of waiting time when compared, for example, with a system that repeatedly asks the interlocutor to wait (even if these requests for waiting are phrased differently each time). Finally, this research shows that it is possible to model human time-buying behavior on a relatively small corpus, and that a system using such a model can be preferred by participants over one employing a simpler strategy, such as randomly choosing utterances to produce during the wait —even when the utterances used by both strategies are the same.},
  language  = {en}
}
@phdthesis{Kuhnke2021,
  author    = {Kuhnke, Philipp},
  title     = {The neural basis of conceptual knowledge retrieval},
  doi       = {10.25932/publishup-51441},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-514414},
  school      = {Universit{\"a}t Potsdam},
  pages     = {133},
  year      = {2021},
  abstract  = {Conceptual knowledge about objects, people and events in the world is central to human cognition, underlying core cognitive abilities such as object recognition and use, and word comprehension. Previous research indicates that concepts consist of perceptual and motor features represented in modality-specific perceptual-motor brain regions. In addition, cross-modal convergence zones integrate modality-specific features into more abstract conceptual representations. However, several questions remain open: First, to what extent does the retrieval of perceptual-motor features depend on the concurrent task? Second, how do modality-specific and cross-modal regions interact during conceptual knowledge retrieval? Third, which brain regions are causally relevant for conceptually-guided behavior? This thesis addresses these three key issues using functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) in the healthy human brain. Study 1 - an fMRI activation study - tested to what extent the retrieval of sound and action features of concepts, and the resulting engagement of auditory and somatomotor brain regions depend on the concurrent task. 40 healthy human participants performed three different tasks - lexical decision, sound judgment, and action judgment - on words with a high or low association to sounds and actions. We found that modality-specific regions selectively respond to task-relevant features: Auditory regions selectively responded to sound features during sound judgments, and somatomotor regions selectively responded to action features during action judgments. Unexpectedly, several regions (e.g. the left posterior parietal cortex; PPC) exhibited a task-dependent response to both sound and action features. We propose these regions to be "multimodal", and not "amodal", convergence zones which retain modality-specific information. Study 2 - an fMRI connectivity study - investigated the functional interaction between modality-specific and multimodal areas during conceptual knowledge retrieval. Using the above fMRI data, we asked (1) whether modality-specific and multimodal regions are functionally coupled during sound and action feature retrieval, (2) whether their coupling depends on the task, (3) whether information flows bottom-up, top-down, or bidirectionally, and (4) whether their coupling is behaviorally relevant. We found that functional coupling between multimodal and modality-specific areas is task-dependent, bidirectional, and relevant for conceptually-guided behavior. Left PPC acted as a connectivity "switchboard" that flexibly adapted its coupling to task-relevant modality-specific nodes. Hence, neuroimaging studies 1 and 2 suggested a key role of left PPC as a multimodal convergence zone for conceptual knowledge. However, as neuroimaging is correlational, it remained unknown whether left PPC plays a causal role as a multimodal conceptual hub. Therefore, study 3 - a TMS study - tested the causal relevance of left PPC for sound and action feature retrieval. We found that TMS over left PPC selectively impaired action judgments on low sound-low action words, as compared to sham stimulation. Computational simulations of the TMS-induced electrical field revealed that stronger stimulation of left PPC was associated with worse performance on action, but not sound, judgments. These results indicate that left PPC causally supports conceptual processing when action knowledge is task-relevant and cannot be compensated by sound knowledge. Our findings suggest that left PPC is specialized for action knowledge, challenging the view of left PPC as a multimodal conceptual hub. Overall, our studies support "hybrid theories" which posit that conceptual processing involves both modality-specific perceptual-motor regions and cross-modal convergence zones. In our new model of the conceptual system, we propose conceptual processing to rely on a representational hierarchy from modality-specific to multimodal up to amodal brain regions. Crucially, this hierarchical system is flexible, with different regions and connections being engaged in a task-dependent fashion. Our model not only reconciles the seemingly opposing grounded cognition and amodal theories, it also incorporates task dependency of conceptually-related brain activity and connectivity, thereby resolving several current issues on the neural basis of conceptual knowledge retrieval.},
  language  = {en}
}
@phdthesis{Harding2016,
  author    = {Harding, Eleanor Elizabeth},
  title     = {Neurocognitive entrainment to meter influences syntactic comprehension in music and language},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-102258},
  school      = {Universit{\"a}t Potsdam},
  pages     = {vi, 318},
  year      = {2016},
  abstract  = {Meter and syntax have overlapping elements in music and speech domains, and individual differences have been documented in both meter perception and syntactic comprehension paradigms. Previous evidence insinuated but never fully explored the relationship that metrical structure has to syntactic comprehension, the comparability of these processes across music and language domains, and the respective role of individual differences. This dissertation aimed to investigate neurocognitive entrainment to meter in music and language, the impact that neurocognitive entrainment had on syntactic comprehension, and whether individual differences in musical expertise, temporal perception and working memory played a role during these processes. A theoretical framework was developed, which linked neural entrainment, cognitive entrainment, and syntactic comprehension while detailing previously documented effects of individual differences on meter perception and syntactic comprehension. The framework was developed in both music and language domains and was tested using behavioral and EEG methods across three studies (seven experiments). In order to satisfy empirical evaluation of neurocognitive entrainment and syntactic aspects of the framework, original melodies and sentences were composed. Each item had four permutations: regular and irregular metricality, based on the hierarchical organization of strong and weak notes and syllables, and preferred and non-preferred syntax, based on structurally alternate endings. The framework predicted — for both music and language domains — greater neurocognitive entrainment in regular compared to irregular metricality conditions, and accordingly, better syntactic integration in regular compared to irregular metricality conditions. Individual differences among participants were expected for both entrainment and syntactic processes. Altogether, the dissertation was able to support a holistic account of neurocognitive entrainment to musical meter and its subsequent influence on syntactic integration of melodies, with musician participants. The theoretical predictions were not upheld in the language domain with musician participants, but initial behavioral evidence in combination with previous EEG evidence suggest that perhaps non-musician language EEG data would support the framework's predictions. Musicians' deviation from hypothesized results in the language domain were suspected to reflect heightened perception of acoustic features stemming from musical training, which caused current 'overly' regular stimuli to distract the cognitive system. The individual-differences approach was vindicated by the surfacing of two factors scores, Verbal Working Memory and Time and Pitch Discrimination, which in turn correlated with multiple experimental data across the three studies.},
  language  = {en}
}
@phdthesis{Ballnat2012,
  author    = {Ballnat, Silvana},
  title     = {Das Verh{\"a}ltnis zwischen den Begriffen "Erfahrung" und "Sprache" ausgehend von Hans-Georg Gadamers "Wahrheit und Methode" : eine antireduktionistische Lesart gegen Relativismusvorw{\"u}rfe},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  isbn      = {978-3-86956-176-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-59047},
  school      = {Universit{\"a}t Potsdam},
  pages     = {358},
  year      = {2012},
  abstract  = {Meiner nichtreduktionistischen Lesart Gadamers, derzufolge eine wechselseitige konstitutive Relation zwischen „Sprache" und „Erfahrung" besteht, ist es gestattet, den Vorwurf, die Sprachphilosophie Gadamers f{\"u}hre in den Relativismus, den man h{\"a}ufig gegen{\"u}ber sprachphilosophischen Positionen erhebt, abzuweisen. Manchen Denkern zufolge haben die Philosophen der Postmoderne, zu denen auch Gadamer gez{\"a}hlt wurde, eine einfache Umkehrung der beiden Pole des modernen Verh{\"a}ltnisses „Sprache" - „Erfahrung" vollzogen: W{\"a}hrend die Sprache in der Moderne in ihrer Bedingtheit zur Erfahrung und als bloßes Ausdrucksmittel verstanden wurde, wurde dieses Verh{\"a}ltnis in der neueren Philosophie nur umgekehrt, insofern die Philosophie in der Sprache das Fundament f{\"u}r die Erfahrung sehe, wonach die Erfahrung als ein Ausdruck der Sprache erscheine. Die vorliegende Arbeit setzt sich mit diesem Relativismusvorwurf auseinander und beabsichtigt, eine wechselseitige Abh{\"a}ngigkeit zwischen Sprache und Erfahrung ausgehend von Hans-Georg Gadamers Werk zu entwickeln. Um das zu erreichen, wurden zun{\"a}chst eine doppelte negative-positive Erfahrungsstruktur und dann einige ph{\"a}nomenologische und transzendentale Merkmale der Erfahrung auf dem historischen Hintergrund f{\"u}r Gadamers Erfahrungsbegriff herausgearbeitet. Somit machte sich die konstitutive Sprachlichkeit der Erfahrung erkennbar. In einer Auseinandersetzung mit dem Sprachbegriff auf der anderen Seite wurde sein dialogischer und welterschließender Charakter veranschaulicht, so dass auch seine Angewiesenheit auf die Welterfahrung offenkundig wurde.},
  language  = {de}
}