Research Interests
My research focus is on Auditory Cognitive Neuroscience with a particular focus on speech perception, bridging the gap between Cognitive Psychology/Neuroscience and the Linguistic disciplines Phonetics, Phonology, and Morphology. A further interdisciplinary research interest relates to aesthetic aspects of speech perception.
Auditory Cognitive NeuroscienceHow are auditory categories formed? My research interest concerns behavioral as well as brain imaging signatures for auditory category learning. How can the brain selectively attend to particular cues in complex sounds (including speech), and how does internal or external noise affect this ability? Our research models response strategies in auditory categorization that lets us better understand how acoustic cues are adaptively used, and what role selective attention plays in adaptive listening behavior. A further interest is how the auditory system gains stability by predictive mechanisms, and how speech makes use of these auditory capacities. Necessarily, an entailment of this research is how far speech is special. PhoneticsHow is speech characterized acoustically? What are phonetic categories, what acoustic cues are used to perceive these categories, and how are these categories represented? These questions are in the center of my phonetic research. I have worked on speech perception models using invariant features which classify the surface characteristics of speech sounds. Phonetic features appear to be language specific, and even differ between dialects. However, the features are robust with regard to extra-linguistic information (i.e. information which is not primarily used to distinguish between speech sounds). Extra-linguistic information seems to be evaluated in parallel and can tune or alter the formation of phonetic categories from the acoustic input. PhonologyMy approach to phonology is based on featural representations. These representations are a further abstraction from the phonetic (surface) feature. They capture and account for phenomena such as allophony, vowel harmony, or assimilation. A further underlying assumption is that certain feature values are not specified and that this non-specification is informative if evaluated against other, specified features. Crucially, the interface of phonetic and phonological processing is characterized by a mapping mechanism of phonetic onto more abstract phonological features. Phonological representations are language-specific insofar as they determine the organization and structure of the sound space in each language. I have also been working on the featural modelling of diachronic change and grammaticalization. MorphologyThe main focus in morphology is on inflectional processes. I assume a Lexical Phonologist framework, which I think is compatible with the featural phonological assumptions. I have worked on the Umlaut alternation in the plural of German nouns and tried to provide a synchronic as well as a diachronic featural account. Another area of interest covers the organization of inflectional classes and the processing of regular versus irregular inflectional forms. With regard to German verbs, I think that learnability improves if the irregular preterite forms are taken as the basis, instead of the infinite forms. PsycholinguisticsPsycholinguistics in my view is the experimental assessment of linguistic competence and performance in all areas of Linguistics by means of psychological, behavioural methods. Based on my interests in Phonetics, Phonology, and Morphology, my psycholinguistic experiments have concentrated on these realms. In Phonetics, experimental work involved categorical perception experiments, identification and discrimination of speech sounds. In Phonology, I have used the gating paradigm, while for Morphology and the morpho-phonological interface, the experimental method has been lexical decision with priming (form priming, morphological priming, semantic priming). Although my focus is on spoken language, my experiments in Psycholinguistics have always been concerned with orthographic effects on auditory perception. Regarding language change, I have worked on the New Zealand English short front vowel shift in comparison to American English varities without such changes. NeurolinguisticsNeurolinguistics for me provides the surrounding for the bigger picture regarding language in human beings. I see it as a discipline which can make crucial contributions towards a better understanding of the neuronal underpinnings of human language. My fields of neurolinguistic expertise are in EEG and MEG. I have conducted several studies concerned with theory-driven questions in Phonetics, Phonology, and Morphology. Using ERPs, I investigated the German Umlaut alternation and the time course of lexical access in semantic fragment priming. In my MEG studies (using data from sensor as well as source space), I tackled the issues of acoustic-gradient versus phonological-categorical perception. Further, I am interested in testing the abstractness of phonological features with regard to their acoustic and articulatory bases. Finally, based on psycholinguistic work on English varities and dialects, I found evidence of dialectal categories which are extracted very early in the course of speech perception. Aesthetic SpeechFinally, I am interested in non-communicative functions of speech, predominantly in aesthetic usage and appreciation of speech and its relation to music, as seen in poetry. Here, I am focusing on regular (predictable) aspects of temporal and spectral characteristics (i.e. meter and rhyme), how they can be quantified and how they can be measured using behavioral and neuroimaging methods. |