Hellmuth Obrig's research while affiliated with University of Leipzig and other places

Publications (209)

Article
Full-text available
Infants rapidly advance in their speech perception, electrophysiologically reflected in the transition from an immature, positive-going to an adult-like, negative-going mismatch response (MMR) to auditory deviancy. Although the MMR is a common tool to study speech perception development, it is not yet completely understood how different speech cont...
Article
For experimental research on language production, temporal precision and high quality of the recorded audio files are imperative. These requirements are a considerable challenge if language production is to be investigated online. However, online research has huge potential in terms of efficiency, ecological validity and diversity of study populati...
Article
Background: Primary progressive aphasia (PPA) may present with three distinct clinical sybtypes: semantic variant PPA (svPPA), nonfluent/agrammatic variant PPA (nfvPPA), and logopenic variant PPA (lvPPA). Objective: The aim was to examine the utility of the German version of the Repeat and Point (R&P) Test for subtyping patients with PPA. Metho...
Article
Full-text available
Introduction: The behavioral variant of frontotemporal dementia (bvFTD) is a rare neurodegenerative disease. Reliable predictors of disease progression have not been sufficiently identified. We investigated multivariate magnetic resonance imaging (MRI) biomarker profiles for their predictive value of individual decline. Methods: One hundred five...
Article
The breakdown of rapid and accurate retrieval of words is a hallmark of aphasic speech and a prime target of therapeutic intervention. Complementary, psycho- and neurolinguistic research have developed a spectrum of models, how and by which neuronal network uncompromised speakers can rely on remarkable lexical retrieval capacities. Motivated by bot...
Article
Our study examines the lexical representation and processing of compounds in participants with aphasia (PWA) and language-unimpaired control speakers. Participants were engaged in primed picture-naming in German, a language that marks for grammatical gender. Gender-marked determiners served as primes (dermasc, diefem, dasneut [the]) and noun-noun c...
Article
Full-text available
Frontotemporal dementia (FTD) is a clinically and genetically heterogeneous disorder. To which extent genetic aberrations dictate clinical presentation remains elusive. We investigated the spectrum of genetic causes and assessed the genotype-driven differences in biomarker profiles, disease severity and clinical manifestation by recruiting 509 FTD...
Article
Full-text available
Background: We require high-quality information on the current burden, the types of therapy and resources available, methods of delivery, care pathways and long-term outcomes for people with aphasia. Aim: To document and inform international delivery of post-stroke aphasia treatment, to optimise recovery and reintegration of people with aphasia. Me...
Preprint
For experimental research on language production, temporal precision and high quality of the recorded audio-files are mandatory. These requirements are a considerable challenge if language production is to be investigated online. However, online research has a huge potential regarding efficiency, ecological validity and diversity of study-populatio...
Article
Context can affect language processing and learning. We here compare the influence of two different contexts (pseudo-objects, data from [Obrig, H., Mock, J., Stephan, F., Richter, M., Vignotto, M., & Rossi, S. (2017). Impact of associative word learning on phonotactic processing in 6-month-old infants: A combined EEG and fNIRS study. Developmental...
Article
People with right hemisphere brain lesions (PRHL) are often faced with impairments in their communicative abilities, which can impact their participation. These impairments may be related to diminished executive functions and/or reduced attentional or socio-cognitive capacities. PRHL can also be a!ected by deficits in processing of linguistic proso...
Article
When we refer to an object or concept by its name, activation of semantic and categorical information is necessary to retrieve the correct lexical representation. Whereas in neurotypical individuals it is well established that semantic context can interfere with or facilitate lexical retrieval, these effects are much less studied in people with les...
Conference Paper
In unserer Studie untersuchen wir die rezeptiven Fähigkeiten zur Identifikation prosodisch markierter Grenzen von P-RHL und P-LHL bei unterschiedlicher Kombination und Ausprägung der drei prosodischen Cues Pausendauer, f0-Variation und finale Längung.
Article
Full-text available
Semantic composition is the ability to combine single words to form complex meanings and is an essential component for successful communication. Evidence from neuroimaging studies suggests that semantic composition engages a widely distributed left-hemispheric network, including the anterior temporal lobe, the inferior frontal gyrus and the angular...
Preprint
The breakdown of rapid and accurate retrieval of words is a hallmark of aphasic speech and a prime target of therapeutic intervention. Complementary, psycho- and neurolinguistic research have developed a spectrum of models, how and by which neuronal network uncompromised speakers can rely on remarkable lexical retrieval capacities. Motivated by bot...
Article
Full-text available
The application of functional near-infrared spectroscopy (fNIRS) in the neurosciences has been expanding over the last 40 years. Today, it is addressing a wide range of applications within different populations and utilizes a great variety of experimental paradigms. With the rapid growth and the diversification of research methods, some inconsisten...
Preprint
When we refer to an object or concept by its name, activation of semantic and categorical information is necessary to retrieve the correct lexical representation. While in neurotypical participants it is well established that semantic context can interfere with or facilitate lexical retrieval, these effects are much less studied in people with lesi...
Article
: Communication disorders following acquired brain damage without aphasia are often overlooked despite their importance for rehabilitation. We invited 52 patients with traumatic brain injury (TBI) and their relatives to directly assess changes in communicative abilities and the resulting impairment. Patients and relatives experienced a similar decl...
Article
Aim To evaluate the combined effect of compensation therapy and functional training on working memory (WM) in patients with acquired injury and chronic cognitive deficits by investigating the dose-response relationship and specificity of transfer effects. Research design Double-blind randomized controlled trial. Methods All patients underwent 4 w...
Article
Full-text available
Semantic context modulates precision and speed of language production. Using different experimental designs including the Picture-Word-Interference (PWI) paradigm, it has consistently been shown that categorically related distractor words (e.g., cat) inhibit retrieval of the target picture name (dog). Here we introduce a novel variant of the PWI pa...
Article
Full-text available
Language is sustained by large-scale networks in the human brain. Stroke often severely affects function and network dynamics. However, the adaptive potential of the brain to compensate for lesions is poorly understood. A key question is whether upregulation of the right hemisphere is adaptive for language recovery. Targeting the potential for shor...
Article
ZUSAMMENFASSUNG Aphasie ist ein typisches Symptom links fronto-temporaler Läsionen. Nicht selten werden aphasische Symptome jedoch auch nach subkortikalen Läsionen z. B. im Thalamus beschrieben. Als Ursache für aphasische Symptome bei Thalamusschädigungen vermutet man die Störung eines thalamo-kortikalen Sprachnetzwerkes. Die Rolle des Thalamus in...
Article
Full-text available
The generation of hierarchical structures is central to language, music and complex action. Understanding this capacity and its potential impairments requires mapping its underlying cognitive processes to the respective neuronal underpinnings. In language, left inferior frontal gyrus and left posterior temporal cortex (superior temporal sulcus/midd...
Preprint
Semantic context modulates precision and speed of language production. Using different experimental designs including the Picture-Word-Interference (PWI) paradigm, it has consistently been shown that categorically related distractor words (e.g., cat) inhibit retrieval of the target picture name (dog). Here we introduce a novel variant of the PWI pa...
Article
Musical excerpts have been shown to have the capacity to prime the processing of target words and vice versa, strongly suggesting that music can convey concepts. However, to date no study has investigated an influence of musical semantics on novel word acquisition, thus corroborating evidence for a similarity of underlying semantic processing of mu...
Article
Full-text available
Studies of novel noun learning show bilingual children rely less on the Mutual Exclusivity Constraint (MEC) for word learning than monolinguals. Shifting the focus to learning novel property terms (adjectives), the present study compared 3.5- and five-year-old bilingual and monolingual preschoolers’ adherence to the MEC. We found no bilingual-monol...
Article
Full-text available
Physical exercise has been suggested to improve cognitive performance through various neurobiological mechanisms, mediated by growth factors such as BDNF, IGF-I, and VEGF. Moreover, animal research has demonstrated that combined physical and cognitive stimulation leads to increased adult neurogenesis as compared to either experimental condition alo...
Article
Full-text available
Recognizing the identity of others by their voice is an important skill for social interactions. To date, it remains controversial which parts of the brain are critical structures for this skill. Based on neuroimaging findings, standard models of person-identity recognition suggest that the right temporal lobe is the hub for voice-identity recognit...
Article
Physical exercise is known to improve memory functions in both animals and humans by inducing various plastic changes in the hippocampus. The present study assumed that physical exercise thus could help to increase the effects of a subsequent hippocampus-dependent cognitive training on directly assessed training outcomes as well as on cognitive tra...
Article
Human voice recognition is an essential skill for social interactions. The mechanisms that the human brain uses for voice recognition are to-date unknown. According to studies in patients with brain lesions, voice recognition critically involves the bilateral temporal lobe and the right inferior parietal lobe. In contrast, functional magnetic reson...
Article
Full-text available
Previous studies have shown bilingually and monolingually developing children to differ in their sensitivity to referential pragmatic deixis in challenging tasks, with bilinguals exhibiting a higher sensitivity. The learning of adjectives is particularly challenging, but has rarely been investigated in bilingual children. In the present study we pr...
Article
Background: Treatment guidelines for aphasia recommend intensive speech and language therapy for chronic (≥6 months) aphasia after stroke, but large-scale, class 1 randomised controlled trials on treatment effectiveness are scarce. We aimed to examine whether 3 weeks of intensive speech and language therapy under routine clinical conditions improv...
Article
Full-text available
During early language development native phonotactics are acquired in a ‘bottom-up’ fashion, relying on exquisite auditory differentiation skills operational from birth. Since basic lexico-semantic abilities have been demonstrated from 6 months onwards, ‘top-down’ influences on phonotactic learning may complement the extraction of transitional prob...
Article
View largeDownload slide See Cappa (doi: 10.1093/brain/aww090 ) for a scientific commentary on this article. The phonological structure of speech supports the automatic mapping of sound to meaning. Using a novel combined EEG-lesion approach in patients with chronic left hemisphere lesions and healthy controls, Obrig et al. disentangle contributio...
Article
In humans, action errors and perceptual novelty elicit activity in a shared frontostriatal brain network, allowing them to adapt their ongoing behavior to such unexpected action outcomes. Healthy and pathologic aging reduces the integrity of white matter pathways that connect individual hubs of such networks and can impair the associated cognitive...
Article
Full-text available
Recently, biomarkers have been suggested to be incorporated into diagnostic criteria for Alzheimer's disease (AD). Regarding disease-specific brain amyloid-beta deposition these comprise low amyloid-beta 1-42 in cerebrospinal fluid (CSF) and positive positron emission tomography (PET) amyloid imaging, while neuronal degeneration is evidenced by hig...
Article
One way to investigate the neuronal underpinnings of language competence is to correlate patholinguistic profiles of aphasic patients to corresponding lesion sites. Constituting the beginnings of aphasiology and neurolinguistics over a century ago, this approach has been revived and refined in the past decade by statistical approaches mapping conti...
Article
Full-text available
Dynamic near-infrared fluorescence (DNIF) whole-body imaging of small animals has become a popular tool in experimental biomedical research. In humans, however, the field of view has been limited to body parts, such as rheumatoid hands, diabetic feet or sentinel lymph nodes. Here we present a new whole-body DNIF-system suitable for adult subjects....
Article
Full-text available
Perceptual learning requires the generalization of categorical perceptual sensitivity from trained to untrained items. For degraded speech, perceptual learning modulates activation in a left-lateralized network, including inferior frontal gyrus (IFG) and inferior parietal cortex (IPC). Here we demonstrate that facilitatory anodal transcranial direc...
Article
Gestures accompany speech and enrich human communication. When aphasia interferes with verbal abilities, gestures become even more relevant, compensating for and/or facilitating verbal communication. However, small-scale clinical studies yielded diverging results with regard to a therapeutic gesture benefit for lexical retrieval. Based on recent fu...
Article
Full-text available
Functional near infrared spectroscopy (fNIRS) is a versatile neuroimaging tool with an increasing acceptance in the neuroimaging community. While often lauded for its portability, most of the fNIRS setups employed in neuroscientific research still impose usage in a laboratory environment. We present a wearable, multi-channel fNIRS imaging system fo...
Article
Near-Infrared Spectroscopy (NIRS) has become a relevant research tool in neuroscience. In special populations such as infants and for special tasks such as walking, NIRS has asserted itself as a low resolution functional imaging technique which profits from its ease of application, portability and the option to co-register other neurophysiological...
Conference Paper
Einleitung: Bestimmte Komponenten ereigniskorrelierter Potenziale werden ganz besonders durch Aufmerksamkeitsfunktionen moduliert. Unbestritten ist, dass die Amplitude der P300 durch die Aufmerksamkeitsintensität moduliert wird: Größere Amplituden ergeben sich in Versuchsbedingungen, bei denen die zugrundeliegende Aufgabe viel Aufmerksamkeit erfor...
Article
In two experiments we investigate how repeated exposure to native and non-native phonotactic regularities alters the N400, an event-related potential related to lexico-semantic access. Participants underwent a Passive Listening (Experiment 1) or a Categorization Training (Experiment 2) for monosyllabic pseudowords over 3 days. During Passive Listen...
Article
Full-text available
Positron emission tomography with [18F] fluorodeoxyglucose (FDG-PET) plays a well-established role in assisting early detection of frontotemporal lobar degeneration (FTLD). Here, we examined the impact of intensity normalization to different reference areas on accuracy of FDG-PET to discriminate between patients with mild FTLD and healthy elderly s...
Article
Though potentially relevant for monitoring of acute stroke, even specialized stroke units do not provide continuous methods to determine cerebral perfusion at the bedside. We present patient measurements on cerebral perfusion in ischemic stroke applying optical bolus tracking. To this end, our portable time-domain near-infrared reflectometer has be...
Article
Full-text available
Response inhibition is an attention function which develops relatively early during childhood. Behavioral data suggest that by the age of 3, children master the basic task requirements for the assessment of response inhibition but performance improves substantially until the age of 7. The neuronal mechanisms underlying these developmental processes...
Article
Meaningful gestures enhance speech comprehensibility. However, their role during novel-word acquisition remains elusive. Here we investigate how meaningful versus meaningless gestures impact on novel-word learning and contrast these conditions to a purely verbal training. After training, neuronal processing of the novel words was assessed by blood-...
Article
Full-text available
To investigate the neural correlates of lucid dreaming. Parallel EEG/fMRI recordings of night sleep. Sleep laboratory and fMRI facilities. Four experienced lucid dreamers. N/A. Out of 4 participants, one subject had 2 episodes of verified lucid REM sleep of sufficient length to be analyzed by fMRI. During lucid dreaming the bilateral precuneus, cun...
Article
Full-text available
Non-invasive detection of fluorescence from the optical tracer indocyanine green is feasible in the adult human brain when employing a time-domain technique with picosecond resolution. A fluorescence-based assessment may offer higher signal-to-noise ratio when compared to bolus tracking relying on changes in time-resolved diffuse reflectance. The e...