Klaus Willmes

Klaus Willmes
University Hospital RWTH Aachen · Department of Neurology

Prof. Dr.

About

518
Publications
128,330
Reads
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17,274
Citations
Introduction
Klaus Willmes is a retired full Professor of Neuropsychology and former Head of the Section Neuropsychology at the Department of Neurology, University Hospital RWTH Aachen.
Additional affiliations
January 1997 - February 2016
University Hospital RWTH Aachen
Position
  • Head Section Neuropsychology until retirement March 1, 2016
March 1979 - present
University Hospital RWTH Aachen
Position
  • Head Section Neuropsychology

Publications

Publications (518)
Poster
Full-text available
A 3-step hierarchical Bayes analysis of the frequency of apraxia of speech in patients with chronic post-stroke aphasia. Step 1: meta-analysis of published frequency data; step 2: survey of expert opinions; step 3: secondary auditory-perceptual analysis of speech samples from a representative sample of patients with post-stroke aphasia, > 6 months...
Article
Background: Creating a holistic picture of children and youth who suffer from acquired aphasia or another (developmental) language disorders is very diffi cult due to missing diagnostic instruments covering participation. Szenario-Kids is a new diagnostic instrument to measure multimodal communication abilities in everyday life situations of childre...
Article
Question: Stroke in the left hemisphere leads to deficits in language, motor cognition, and spatial attention; hereby an isolated lesion can result in deficits in multiple domains. The dual-loop model of a dorsal and ventral processing stream (Weiller, 2011) can serve as a functional-anatomic framework for task-specific but cross-domain processing....
Preprint
Neurometry (a.k.a. quantitative EEG or qEEG) is a popular method to assess clinically relevant abnormalities in the electroencephalogram. Neurometry is based on norm values for the distribution of specific EEG parameters and believed to show good psychometric properties such as test-retest reliability. Many psychometric properties only hold under t...
Article
Apraxia of speech is a motor speech disorder that occurs after lesions to the left cerebral hemisphere, most often concomitant with aphasia. It requires specific approaches in the study of its physiological and neuroanatomical basis and special expertise in clinical care. Knowing its prevalence in patients with aphasia after stroke is therefore rel...
Preprint
Psychological science could greatly benefit from research synthesis, especially when it comes to overcoming limitations of too small samples tested in single studies. However, initiatives aimed at sharing large, curated trial-level data from cognitive tasks remain scarce. To address this problem, we initiated a collective effort allowing to assembl...
Article
Full-text available
A growing body of research suggests that basic numerical abilities such as number magnitude processing are influenced by cognitive control processes. So far, evidence for number processing being affected by cognitive control processes stems primarily from observed adaptations of numerical effects to stimulus set characteristics (e.g. order or ratio...
Article
Background and Aims Research just started to combine behavioural, computational, and neural accounts to investigate the nature of post-stroke aphasia, but the dynamic aspect of aphasia recovery has rarely been integrated. Moreover, executive functions in aphasia recently gained attention as an important contributor to language performance. Lexical...
Article
Background and aims Executive functions recently have gained attention as important contributors to language performance in aphasia. Picture/word interference embraces both executive control and lexical processing through distracted confrontation naming. Thus, we created a novel approach that embedded interfered-naming into an established lexical t...
Article
Full-text available
Recently, it was demonstrated that even basic numerical cognition such as the processing of number magnitude is under cognitive control. However, evidence so far primarily came from adaptation effects to stimulus characteristics (e.g., relative frequency of specific stimulus categories). Expanding this approach, we evaluated a possible influence of...
Article
The aim of the present study was to examine the interplay of morphological configuration switching and language switching. The morphological configuration is present in word-formation whenever a word contains more than one free morpheme. The morphological configuration is variable both within and between languages for example in two-digit number na...
Article
Full-text available
Neurodegenerative diseases such as Parkinson's disease (PD) have a huge impact on patients, caregivers, and the health‐care system. To date, the diagnosis of mild cognitive impairments in PD has been established based on domain‐general functions such as executive functions, attention, or working memory. However, specific numerical deficits observed...
Article
Full-text available
The numerical distance effect (it is easier to compare numbers that are further apart) and size effect (for a constant distance, it is easier to compare smaller numbers) characterize symbolic number processing. However, evidence for a relationship between these two basic phenomena and more complex mathematical skills is mixed. Previously this relat...
Article
Purpose: Over and above language deficits, persons with aphasia can present with impairments in executive functions, including deficits in cognitive flexibility. Cognitive flexibility constitutes the ability to update behaviour quickly and flexibly in a changing environment. Its deficits can restrict communicative ability, e. g. the ability to chan...
Article
Full-text available
Personen mit Aphasie erleben den Verlust ihrer Sprache und ihrer Gesprächsfähigkeit meist als grosse Einschränkung. Deshalb ist ein häufiges Ziel der Sprachtherapie, die Teilhabe an Gesprächen zu verbessern. Studien zeigen, dass für erfolgreiche Gespräche neben sprachlichen Fähigkeiten auch Exekutivfunktionen relevant sind, insbesondere die Umstel...
Article
The aim of this study was to examine language switching in a two-digit number naming task. In contrast to single digits, two-digit numbers have a composition rule (i.e., morphological configuration) that may differ between languages. For example, the Arabic number 21 is read with an inverted composition rule in German (unit before decade) and a non...
Article
Prelexical phonetic capacities have widely been described to be a precursor for later speech and language development. However, studies so far varied greatly in the measurements used for the detection of canonical babbling onset or the description of infants’ phonetic capacities at one or more set time points. The comparability of results is, there...
Article
Full-text available
Bioelectrical impedance spectroscopy (BIS) measures body composition, including fluid status. Acute decompensated heart failure (ADHF) is associated with fluid overload in different body compartments. This investigation aimed to evaluate the feasibility of measuring and monitoring fluid accumulation in patients with ADHF using BIS. The extracellula...
Article
Background and Study Aims Language mapping by navigated transcranial magnetic stimulation (TMS) is commonly applied over the left language-dominant hemisphere to indicate the language-related cortex. Detailed language mapping of Broca's region including stimulation targets in the immediate vicinity to the premotor cortex may raise concern about con...
Preprint
Full-text available
The numerical distance effect (it is easier to compare numbers that are further apart) and size effect (for a constant distance, it is easier to compare smaller numbers) characterize the analogue number magnitude representation. However, evidence for a relationship between these two basic phenomena and more complex mathematical skills is mixed. Pre...
Article
Preterm infants are at risk of experiencing difficulties in their feeding development. For a possible early identification of these, we examined the association between sucking patterns, assisted spoon feeding, and chewing skills in 40 healthy preterm infants, and the role of experience in the acquisition of these skills in a prospective longitudin...
Article
Full-text available
Background Difficult cognitive tasks are often associated with negative feelings. This can be already the case for the mere anticipation of having to do a difficult task. For the case of difficult math tasks, it was recently suggested that such a negative emotional response may be exclusive to highly math-anxious individuals. However, it is also co...
Article
Aim: Knowledge about cardiac stress related to seizures in electroconvulsive therapy (ECT) and spontaneously occurring generalized convulsive seizures (GCS) is limited. The aim of the present study was to analyze cardiac function and circulating markers of cardiac stress in the early postictal period after ECT and GCS. Methods: Patients undergoi...
Preprint
Full-text available
Recently, it was demonstrated that even basic numerical cognition such as the processing of number magnitude is under cognitive control. However, evidence so far primarily came from adaptation effects to stimulus characteristics (e.g., relative frequency of specific stimulus categories). Expanding this approach, we evaluated a possible influence of...
Preprint
The aim of cognitive psychology is to obtain insights into human cognition in general. For this purpose, group-studies are typically conducted on representative samples so that the results can be generalized to the population. Using this approach, individual differences in such group-level cognitive phenomena are typically neglected and not much is...
Article
Full-text available
Functional imaging data suggest different regions for semantic, syntactic, and phonological processing in an anterior-to-posterior direction along the inferior frontal gyrus. Language mapping by use of neuro-navigated transcranial magnetic stimulation (TMS) is frequently applied in clinical research to identify language-related cortical regions. Re...
Article
Introduction: Data on the frequency and clinical relevance of neurogenic pulmonary edema (NPE) following epileptic seizures are limited. The aim of the present study was to analyze computed tomography (CT) examinations in patients with previous seizures. Method: Incidence of NPE and related clinical factors were retrospectively assessed in patie...
Article
Besides language deficits, persons with aphasia can present with impairments in executive functions such as cognitive flexibility. Since these impairments can restrict communicative abilities, diagnostics for aphasia should include their assessment. However, tests of executive functions, including symptoms expressed in everyday communication, are l...
Article
Full-text available
Previous lesion studies suggest that semantic and phonological fluency are differentially subserved by distinct brain regions in the left temporal and the left frontal cortex, respectively. However, as of yet, this often implied double dissociation has not been explicitly investigated due to mainly two reasons: (i) the lack of sufficiently large sa...
Article
Full-text available
Developmental dysgraphia is a disorder of writing/spelling skills, closely related to developmental dyslexia. For developmental dyslexia, profiles with a focus on phonological, attentional, visual or auditory deficits have recently been established. Unlike for developmental dyslexia, however, there are only few studies about dysgraphia, in particul...
Article
Verbally-mediated arithmetic fact retrieval has been suggested to be subserved by a left-lateralized network including angular gyrus and hippocampus. However, the contribution of these areas to retrieval of arithmetic facts has been under debate lately, challenging the prominent role of the angular gyrus in arithmetic fact retrieval. In the present...
Article
Background: Access to reperfusion therapies in patients with large vessel occluding acute ischemic stroke demands process reorganization and optimization. Neurovascular networks are being built up to provide 24/7 endovascular stroke therapy service. In times of an increasingly complex stroke rescue chain little is known about patients' and their r...
Article
Full-text available
Broca's region, corresponding roughly to cytoarchitectonic areas 44 and 45 in the inferior frontal cortex, holds a multifunctional role in language processing, as shown, e.g., by functional imaging data. Neuro-navigated transcranial magnetic stimulation (TMS) enables complementary non-invasive mapping of cortical functions with high spatial resolut...
Article
Background: Laboratory parameters can help in the differential diagnostics of acute episodes of transient loss of consciousness. Especially serum lactate and serum creatine kinase (CK) levels may provide valuable hints to distinguish generalized tonic-clonic seizures (GTCS) from syncope. Material and methods: Serum lactate levels at admission an...
Article
Full-text available
The Abbreviated Math Anxiety Scale (AMAS) is one of the most popular instruments measuring math anxiety (MA). It has been validated across several linguistic and cultural contexts. In this study, we investigated the extent of administration method invariance of the AMAS by comparing results (average scores, reliabilities, factorial structure) obtai...
Article
Besides language deficits, persons with aphasia (PWA) can have impairments in cognitive flexibility, which may influence communicative abilities negatively. The aim of the present study was to evaluate whether therapy including cognitive flexibility leads to improvement in language skills as well as in communicative abilities. 10 single case studie...
Article
In "Two heads are better than one," "head" stands for people and focuses the message on the intelligence of people. This is an example of figurative language through metonymy, where substituting a whole entity by one of its parts focuses attention on a specific aspect of the entity. Whereas metaphors, another figurative language device, are substit...
Article
Background: SAPS-'Sprachsystematisches Aphasiescreening'-is a novel language-systematic aphasia screening developed for the German language, which already had been positively evaluated. It offers a fast assessment of modality-specific psycholinguistic components at different levels of complexity and the derivation of impairment-based treatment foc...
Poster
Full-text available
Während Einigkeit darüber besteht, dass in der neurochirurgischen Therapieplanung präoperative fMRT nicht nur das Outcome der Patienten verbessert und Liegezeiten im Krankenhaus kosteneffizient verkürzt, variieren die neuroradiologischen Scanningprotokolle regional stark. Dies gilt insbesondere für die Scanningparameter Voxelgröße (VG) und Bildwied...
Article
Full-text available
Premature birth is a significant risk factor for learning disabilities in general and mathematics learning difficulties in particular. However, the exact reasons for this relation are still unknown. While typical numerical development is associated with a frontal-to-parietal shift of brain activation with increasing age, influences of gestational a...
Article
Concentrations of serum creatine kinase (CK) and serum lactate are frequently measured to help differentiate between generalized tonic–clonic seizures (GTCS) and syncope. The aim of this prospective cohort study was to systematically compare these two markers. The primary outcome is the measurement of serum lactate and CK in blood samples drawn wit...
Article
In the context of a health surveillance program for former PCB-exposed workers of a transformer and capacitor recycling company in Germany, their family members, employees of surrounding companies and area residents a broad range of cognitive functions covering attention, executive processing, reasoning, memory and motor performance was examined. T...
Presentation
Full-text available
Theoretischer Hintergrund: Studien belegen, dass die semantische und syntaktische Informationsverarbeitung bei erwachsenen CI-Trägern in Abhängigkeit vom sprachlichen Input variiert. Vor allem die Verarbeitung morpho-syntaktischer Elemente der gesprochenen Sprache scheint aufgrund des eingeschränkten Hörvermögens störungsanfälliger zu sein (Hahne &...
Article
Full-text available
In the field of numerical cognition it is often highlighted that the domain-specific systems, referred to as “Approximate Number System” (ANS), or “The Number Sense” (NS)1, constitute the basis for mathematical skills (Feigenson et al., 2004; Dehaene, 2011). However, recently, Leibovich et al. (2016) stressed the role of domain-general factors, esp...
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
In the current study, we addressed modality-specificity of the flexibility of cognitive control. We compared performance in single-task and mixed-tasks blocks between blocked auditory and visual stimuli assessing alternation costs (single vs. mixed). Mixed blocks comprised task switches only. The tasks consisted of numerical parity, magnitude, and...
Article
Imitation of tool-use gestures (transitive; e.g., hammering) and communicative emblems (intransitive; e.g., waving goodbye) is frequently impaired after left-hemispheric lesions. We aimed 1) to identify lesions related to deficient transitive or intransitive gestures, 2) to delineate regions associated with distinct error types (e.g., hand configur...
Article
Do long-term tongue piercings affect speech quality? Purpose: To explore possible effects of tongue piercing on perceived speech quality. Methods: Using a quasi-experimental design, we analyzed the effect of tongue piercing on speech in a perception experiment. Samples of spontaneous speech and read speech were recorded from 20 long-term pierced...
Article
Full-text available
The approximate number system (ANS) was proposed to be a building block for later mathematical abilities. Several measures have been used interchangeably to assess ANS acuity. Some of these measures were based on accuracy data, whereas others relied on response time (RT) data or combined accuracy and RT data. Previous studies challenged the view th...
Article
Different models have been proposed for the processing of multisymbol numbers like two- and three-digit numbers but also for negative numbers and decimals. However, these multisymbol numbers are assembled from the same set of Arabic digits and comply with the place-value structure of the Arabic number system. Considering these shared properties, we...
Article
Assessing communicative-pragmatic performance in childhood aphasia is hardly possible with the currently available test instruments. However, affected children are in risk of long-term consequences regarding their communicative skills and social participation. Developed in 2015, the Szenario-Kids is a diagnostic instrument for the evaluation of mul...
Article
Background: Re-learning of lexical entries is fundamental to rehabilitation of the common word finding deficits in language disorders after brain damage. Previous studies examined and compared neural correlates of speech production and word learning in aphasic and healthy speakers, but longitudinal control studies were rarely set out to mimic the l...