- Name: Prof. Dr. rer. nat. Klaus Willmes - von Hinckeldey Position: Retired Head: Section Neuropsychology at the Depar... moreName: Prof. Dr. rer. nat. Klaus Willmes - von Hinckeldey Position: Retired Head: Section Neuropsychology at the Department of Neurology, School of Medicine RWTH Aachen University Business address: Uniklinik RWTH Aachen Klinik für Neurologie Pauwelsstrasse 30 D-52074 Aachen Germany E-mail:willmes@neuropsych.rwth-aachen.de Date of birth: September 11th, 1950 Studies:Mathematics (diploma 1974), Psychology (diploma 1979) Aachen Doctorate: 1987, University of Trier, Psychology (Dr. rer. nat) Habilitation: 1994, Psychology, at the Faculty of Psychology, University of Bielefeld (Title: Psychometrics in Neuropsychology)Postgraduate- 1997-2016 full professor of neuropsychology and Head of Section Neuropsychology, Medical Faculty RWTH Aachen Universityedit
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... more
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 substitutions based on similarity, metonymy involves substitutions based on associations. Both are figures of speech but are also expressed in coverbal gestures during multimodal communication. The closest neuropsychological studies of metonymy in gestures have been nonlinguistic tool-use, illustrated by the classic apraxic problem of body-part-as-object (BPO, equivalent to an internal metonymy representation of the tool) vs. pantomimed action (external metonymy representation of the absent object/tool). Combining these research domains with concepts in cognitive linguistic research on gestures, we conducted an fMRI study to investigate metonymy resolution in coverbal gestures. Given the greater difficulty in developmental and apraxia studies, perhaps explained by the more complex semantic inferencing involved for external metonymy than for internal metonymy representations, we hypothesized that external metonymy resolution requires greater processing demands and that the neural resources supporting metonymy resolution would modulate regions involved in semantic processing. We found that there are indeed greater activations for external than for internal metonymy resolution in the temporoparietal junction (TPJ). This area is posterior to the lateral temporal regions recruited by metaphor processing. Effective connectivity analysis confirmed our hypothesis that metonymy resolution modulates areas implicated in semantic processing. We interpret our results in an interdisciplinary view of what metonymy in action can reveal about abstract cognition.
Research Interests:
The lack of a standardized Thai Language aphasia test raises difficulties not only with the assessment and treatment planning for the clinical but also with the accurate diagnosis and the reliable incidence for research on aphasiology in... more
The lack of a standardized Thai Language aphasia test raises difficulties not only with the assessment and treatment planning for the clinical but also with the accurate diagnosis and the reliable incidence for research on aphasiology in Thailand. This study aimed to use the Thai version of German Aachen aphasia (THAI-AAT), which is systematically adapted according to well-defined linguistic criteria and psychometric requirement, to assess the language deficit of Thai aphasic patients. The subjects participating in this study were 125 aphasia patients, 60 non-aphasic brain damaged patients and 120 normal subjects. The result revealed that the THAI-AAT is linguistically parallel in test design and fulfills the same psychometric properties as the original. The THAI-AAT obtains the goals: to differential diagnosis of aphasia distinguishing it from non-aphasic disturbance and to identify the type of aphasic syndrome.
Research Interests:
Research Interests:
Research Interests:
ABSTRACT
Research Interests:
Functional Magnetic Resonance Imaging (fMRI) data of the brain includes activated parenchymal voxels, corresponding to the paradigm performed, non-activated parenchymal voxels and background voxels. Statistical tests, e.g. using the... more
Functional Magnetic Resonance Imaging (fMRI) data of the brain includes activated parenchymal voxels, corresponding to the paradigm performed, non-activated parenchymal voxels and background voxels. Statistical tests, e.g. using the general linear model approach of SPM or the Kolmogorov-Smirnov (KS) non-parametric statistic, are common 'supervised' techniques to look for activation in functional brain MRI. Selection of voxel type by comparing the
Research Interests: Functional Analysis, Modeling, Magnetic Resonance Imaging, Scanning Probe Microscopy, Neural Networks, and 15 moreNeural Network, Magnetism, Technique, Magnetic Susceptibility, Differentiation, Self Organization, General Linear Model, Self Organized Map, Statistical Test, Non parametric statistics, Nuclear Magnetic Resonance Imaging, Hemodynamic Response Function, Time Course, Euclidean Distance, and Feature Space
Recent research indicated that processes as easy as two-digit number comparison are under cognitive control. In the present study we evaluated the validity of the cognitive control architecture proposed by Macizo and Herrera (2011, 2012)... more
Recent research indicated that processes as easy as two-digit number comparison are under cognitive control. In the present study we evaluated the validity of the cognitive control architecture proposed by Macizo and Herrera (2011, 2012) to account for their empirical findings regarding the unit-decade compatibility effect: longer responses for unit-decade incompatible (e.g., 37_52, 3<5, but 7>2) as compared to compatible number pairs (e.g., 42_57, 4<5 and 2<7). Artificial neural network models implementing a cognitive control circuit were trained for magnitude comparison on stimulus sets with different proportions of compatible and incompatible pairs (20%, 50% and 80% incompatible pairs). In line with the empirical observations of a proportion congruity effect, the simulated compatibility effect increased with the number of compatible pairs. Finally, with the same model specifications we were also able to simulate the Gratton effect, providing further evidence for cogni...
The present study investigated whether phonological awareness training is an effective intervention to significantly improve reading in German dyslexic third and fourth graders with a phonological awareness deficit, and whether these... more
The present study investigated whether phonological awareness training is an effective intervention to significantly improve reading in German dyslexic third and fourth graders with a phonological awareness deficit, and whether these children can equally benefit from a phonology-based reading training or a visually-based reading training. German speaking dyslexic elementary school children (n=30; M=9.8 years) were matched by forming triplets based on IQ, reading quotient and phonological awareness and then randomly assigned to one out of three interventions (n=10): a phonological awareness training, a phonology-based reading training (phonics instruction), and a visually-based reading training (repeated reading of sight words). A total of 20 training sessions (30 minutes each) were distributed over four weeks. Typical readers (n=10; M=9.5 years) were assigned to the control group. Phonological awareness training directly improves reading comprehension in German dyslexic children wit...
Research Interests:
Functional magnet resonance imaging (fMRI) has become a standard non invasive brain imaging technique delivering high spatial resolution. Brain activation is determined by magnetic susceptibility of the blood oxygen level (BOLD effect)... more
Functional magnet resonance imaging (fMRI) has become a standard non invasive brain imaging technique delivering high spatial resolution. Brain activation is determined by magnetic susceptibility of the blood oxygen level (BOLD effect) during an activation task, e.g. motor, auditory and visual tasks. Usually box-car paradigms have 2 - 4 rest/activation epochs with at least an overall of 50 volumes per
Research Interests: Functional Analysis, Brain Imaging, Neural Networks, Neural Network, Magnetism, and 15 moreMental rotation, Contrast sensitivity, Magnetic Susceptibility, Smoothing, Self Organization, High Resolution, Rest, Regional Cerebral Blood Flow, Self Organized Map, Nuclear Magnetic Resonance Imaging, Mr Imaging, High Spatial Resolution, Hemodynamic Response Function, Feature Space, and Motion Artifact
Research on (hand-)writing has revealed that Exner&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s area subserves transferring linguistic impulses into... more
Research on (hand-)writing has revealed that Exner&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s area subserves transferring linguistic impulses into writing programmes. We report on a patient with a lesion affecting Broca&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s and Exner&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s area suffering from severe peripheral agraphia for letters but not for Arabic digits. Analogous to semantic (magnitude) information in numbers, we developed a specifically tailored writing training: additional mental imagery based semantic information was attached to letters. The training resulted in significant improvements. Imaging data revealed stronger fronto-parietal network activity including perilesional activation around Exner&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s area and precuneus for writing letters to dictation than for writing letters corresponding to their mental image expressions. Follow-up testing showed not only stable training effects but also an activation shift into the left angular gyrus. Results document neuronal correlates of a successful intervention by attaching additional meanings to letters in order to retrieve their grapho-motor patterns. These findings contribute to understanding the impact of Exner&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s area.
Research Interests:
In neuropsychological research, single-cases are often compared with a small control sample. Crawford and colleagues developed inferential methods (i.e., the modified t-test) for such a research design. In the present article, we suggest... more
In neuropsychological research, single-cases are often compared with a small control sample. Crawford and colleagues developed inferential methods (i.e., the modified t-test) for such a research design. In the present article, we suggest an extension of the methods of Crawford and colleagues employing linear mixed models (LMM). We first show that a t-test for the significance of a dummy coded predictor variable in a linear regression is equivalent to the modified t-test of Crawford and colleagues. As an extension to this idea, we then generalized the modified t-test to repeated measures data by using LMMs to compare the performance difference in two conditions observed in a single participant to that of a small control group. The performance of LMMs regarding Type I error rates and statistical power were tested based on Monte-Carlo simulations. We found that starting with about 15-20 participants in the control sample Type I error rates were close to the nominal Type I error rate using the Satterthwaite approximation for the degrees of freedom. Moreover, statistical power was acceptable. Therefore, we conclude that LMMs can be applied successfully to statistically evaluate performance differences between a single-case and a control sample.
Research Interests:
Superior early numerical competencies of children in several Asian countries have (amongst others) been attributed to the higher transparency of their number word systems. Here, we directly investigated this claim by evaluating whether... more
Superior early numerical competencies of children in several Asian countries have (amongst others) been attributed to the higher transparency of their number word systems. Here, we directly investigated this claim by evaluating whether Japanese children&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s transcoding performance when writing numbers to dictation (e.g., &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;twenty five&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; → 25) was less error prone than that of German-speaking children - both in general as well as when considering language-specific attributes of the German number word system such as the inversion property, in particular. In line with this hypothesis we observed that German-speaking children committed more transcoding errors in general than their Japanese peers. Moreover, their error pattern reflected the specific inversion intransparency of the German number-word system. Inversion errors in transcoding represented the most prominent error category in German-speaking children, but were almost absent in Japanese-speaking children. We conclude that the less transparent German number-word system complicates the acquisition of the correspondence between symbolic Arabic numbers and their respective verbal number words.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
The results from a topographic analysis of the early median nerve SEPs allowed to design a method for recording and analysing the SEPs in the routine laboratory. The detailed analysis of the topography of 50 normal subjects revealed: 1.... more
The results from a topographic analysis of the early median nerve SEPs allowed to design a method for recording and analysing the SEPs in the routine laboratory. The detailed analysis of the topography of 50 normal subjects revealed: 1. An inter- and intraindividual variability of the location of the maximal amplitudes, 2. A significantly longer latency of the cortical potentials after left side stimulation, 3. A significantly higher amplitude of N20 after left side stimulation and 4. A significantly higher amplitude of the later potentials P25 and N30 after right side stimulation. It was shown that a 4-channel recording from the neck at C7 with a Fz-reference as well as from stimulus contralateral F3, CP3 and P3 or F4, CP4 and P4 with an stimulus contralateral earlobe reference provides all necessary parameters in comparison to an 20-channel recording. The definition of normal values has to take into account these results. Absolute maximum values were taken instead of the standard ...
Research Interests:
Vocal emotions are signaled by specific patterns of prosodic parameters, most notably pitch, phone duration, intensity, and phonation type. Phonation type was so far the least accessible parameter in emotion research, because it was... more
Vocal emotions are signaled by specific patterns of prosodic parameters, most notably pitch, phone duration, intensity, and phonation type. Phonation type was so far the least accessible parameter in emotion research, because it was difficult to extract from speech signals and difficult to manipulate in natural or synthetic speech. The present study built on recent advances in articulatory speech synthesis to exclusively control phonation type in re-synthesized German sentences spoken with seven different emotions. The goal was to find out to what extent the sole change of phonation type affects the perception of these emotions. Therefore, portrayed emotional utterances were re-synthesized with their original phonation type, as well as with each purely breathy, modal, and pressed phonation, and then rated by listeners with respect to the perceived emotions. Highly significant effects of phonation type on the recognition rates of the original emotions were found, except for disgust. ...
Research Interests:
Major theories on the neural basis of schizophrenic core symptoms highlight aberrant salience network activity (insula and anterior cingulate cortex), prefrontal hypoactivation, sensory processing deficits as well as an impaired... more
Major theories on the neural basis of schizophrenic core symptoms highlight aberrant salience network activity (insula and anterior cingulate cortex), prefrontal hypoactivation, sensory processing deficits as well as an impaired connectivity between temporal and prefrontal cortices. The mismatch negativity is a potential biomarker of schizophrenia and its reduction might be a consequence of each of these mechanisms. In contrast to the previous electroencephalographic studies, functional magnetic resonance imaging may disentangle the involved brain networks at high spatial resolution and determine contributions from localized brain responses and functional connectivity to the schizophrenic impairments. Twenty-four patients and 24 matched control subjects underwent functional magnetic resonance imaging during an optimized auditory mismatch task. Haemodynamic responses and functional connectivity were compared between groups. These data sets further entered a diagnostic classification ...
Research Interests:
Different specific mechanisms have been suggested for solving single-digit arithmetic operations. However, the neural correlates underlying basic arithmetic (multiplication, addition, subtraction) are still under debate. In the present... more
Different specific mechanisms have been suggested for solving single-digit arithmetic operations. However, the neural correlates underlying basic arithmetic (multiplication, addition, subtraction) are still under debate. In the present study, we systematically assessed single-digit arithmetic in a group of acute stroke patients (n = 45) with circumscribed left- or right-hemispheric brain lesions. Lesion sites significantly related to impaired performance were found only in the left-hemisphere damaged (LHD) group. Deficits in multiplication and addition were related to subcortical/white matter brain regions differing from those for subtraction tasks, corroborating the notion of distinct processing pathways for different arithmetic tasks. Additionally, our results further point to the importance of investigating fiber pathways in numerical cognition.
Research Interests:
Numbers and space are two semantic primitives that interact with each other. Both recruit brain regions along the dorsal pathway, notably parietal cortex. This makes parietal cortex a candidate for the origin of numerical-spatial... more
Numbers and space are two semantic primitives that interact with each other. Both recruit brain regions along the dorsal pathway, notably parietal cortex. This makes parietal cortex a candidate for the origin of numerical-spatial interaction. The underlying cognitive architecture of the interaction is still under scrutiny. Two classes of explanations can be distinguished. The early interaction approach assumes that numerical and spatial information are integrated into a single representation at a semantic level. A second approach postulates independent semantic representations. Only at the stage of response selection and preparation these two streams interact. In this study we used a numerical landmark task to identify the locus of the interaction between numbers and space. While lying in an MR scanner participants decided on the smaller of two numerical intervals in a visually presented number triplet. The spatial position of the middle number was varied; hence spatial intervals we...
Research Interests:
In an fMRI study the functional networks involved in auditory selective attention for sounds and words were investigated. 24 healthy volunteers (12 male, 12 female) had to respond to a category of targets (animal sounds vs. musical... more
In an fMRI study the functional networks involved in auditory selective attention for sounds and words were investigated. 24 healthy volunteers (12 male, 12 female) had to respond to a category of targets (animal sounds vs. musical instruments, spoken names of instruments vs. animals; 6 targets, 12 nontargets) presented via headphones. Under both the sound and word condition besides left superior and middle temporal lobe activation there was bilateral activity in the superior frontal (including the anterior cingulate cortex ACC), middle and inferior frontal and inferior parietal lobes. Under both conditions we also found cerebellar activity. In general there was a high overlap of the related attention networks for both conditions. The activation patterns revealed a high overlap across stimulus conditions with only slight modulation caused by the quality of the auditory material. For rehabilitation of attention deficits after brain damage this implicates that a single training proced...
Research Interests:
Currently, there are three competing theoretical accounts concerning the nature of two-digit number magnitude representation: a holistic, a strictly decomposed, and a hybrid model. Observation of the unit-decade compatibility effect... more
Currently, there are three competing theoretical accounts concerning the nature of two-digit number magnitude representation: a holistic, a strictly decomposed, and a hybrid model. Observation of the unit-decade compatibility effect (Nuerk et al. in Cognition 82:B25-B33, 2001) challenged the view of two-digit number magnitude to be represented as one integrated entity. However, at the moment there is no study distinguishing between the decomposed and the hybrid model. The present study addressed this issue using a computational modelling approach. Three network models complying with the constraints of all three theoretical models were programmed and trained on two-digit number comparison. Models were compared as to how well they accounted for empirical effects in the most parsimonious way. Generally, this evaluation indicated that the empirical data were simulated best by the strictly decomposed model. Implications of these results for our understanding of the nature of human number...
Research Interests:
Different theories conceptualise dyslexia as either a phonological, attentional, auditory, magnocellular, or automatisation deficit. Such heterogeneity suggests the existence of yet unrecognised subtypes of dyslexics suffering from... more
Different theories conceptualise dyslexia as either a phonological, attentional, auditory, magnocellular, or automatisation deficit. Such heterogeneity suggests the existence of yet unrecognised subtypes of dyslexics suffering from distinguishable deficits. The purpose of the study was to identify cognitive subtypes of dyslexia. Out of 642 children screened for reading ability 49 dyslexics and 48 controls were tested for phonological awareness, auditory discrimination, motion detection, visual attention, and rhythm imitation. A combined cluster and discriminant analysis approach revealed three clusters of dyslexics with different cognitive deficits. Compared to reading-unimpaired children cluster no. 1 had worse phonological awareness; cluster no. 2 had higher attentional costs; cluster no. 3 performed worse in the phonological, auditory, and magnocellular tasks. These results indicate that dyslexia may result from distinct cognitive impairments. As a consequence, prevention and rem...
Research Interests:
We employed a source memory task in an event related fMRI study to dissociate MTL processes associated with either contextual retrieval or item recognition. To introduce context during study, stimuli (photographs of buildings and natural... more
We employed a source memory task in an event related fMRI study to dissociate MTL processes associated with either contextual retrieval or item recognition. To introduce context during study, stimuli (photographs of buildings and natural landscapes) were transformed into one of four single-color-scales: red, blue, yellow, or green. In the subsequent old/new recognition memory test, all stimuli were presented as gray scale photographs, and old-responses were followed by a four-alternative source judgment referring to the color in which the stimulus was presented during study. Our results suggest a clear-cut process dissociation within the human MTL. While an activity increase accompanies successful retrieval of contextual information, an activity decrease provides a familiarity signal that is sufficient for successful item recognition.
Research Interests: Cognitive Science, Magnetic Resonance Imaging, Biology, Face recognition (Psychology), Recognition memory, and 15 moreMedicine, Color Perception, Brain Mapping, Hippocampus, Temporal Lobe, Humans, Female, Male, Reaction Time, Source Memory, Declarative Memory, Oxygen, Adult, Neurosciences, and photic stimulation
The lack of a standardized Thai Language aphasia test raises difficulties not only with the assessment and treatment planning for the clinical but also with the accurate diagnosis and the reliable incidence for research on aphasiology in... more
The lack of a standardized Thai Language aphasia test raises difficulties not only with the assessment and treatment planning for the clinical but also with the accurate diagnosis and the reliable incidence for research on aphasiology in Thailand. This study aimed to use the Thai version of German Aachen aphasia (THAI-AAT), which is systematically adapted according to well-defined linguistic criteria and psychometric requirement, to assess the language deficit of Thai aphasic patients. The subjects participating in this study were 125 aphasia patients, 60 non-aphasic brain damaged patients and 120 normal subjects. The result revealed that the THAI-AAT is linguistically parallel in test design and fulfills the same psychometric properties as the original. The THAI-AAT obtains the goals: to differential diagnosis of aphasia distinguishing it from non-aphasic disturbance and to identify the type of aphasic syndrome.
Research Interests:
The hypothesis of prefrontal-temporolimbic disconnectivity, considered to be relevant to the pathogenesis of schizophrenia, has been tested in 29 drug-naive schizophrenic patients, comparing the active with the remitted state. A... more
The hypothesis of prefrontal-temporolimbic disconnectivity, considered to be relevant to the pathogenesis of schizophrenia, has been tested in 29 drug-naive schizophrenic patients, comparing the active with the remitted state. A pre-post-treatment design was applied to 29 drug-naive schizophrenic inpatients, 18 male, mean age 32 years, 11 female, mean age 32 years, mean duration of illness 29 months. Psychopathological symptoms were assessed using PANSS, regional cerebral blood (rCBF) was measured by HMPAO-SPECT. RCBF values were calculated for 21 regions of interest after normalization to cerebellum, and plotted by Euklidean diagrams using the ordinal, nonmetric, multidimensional scaling method. These diagrams represent similarity correlations visualized as spatial distances. High correlation levels as indicated by small Euklidean distances have been interpreted as functional connectivity. In active schizophrenia, functional disconnectivity was observed between prefrontal and tempo...
Research Interests:
The Aachen Aphasia Test (AAT), originally developed as a test for aphasia language disorders in Germany, consists of six spontaneous speech rating scales and five subtests: Token Test, Repetition, Written Language, Confronting Naming and... more
The Aachen Aphasia Test (AAT), originally developed as a test for aphasia language disorders in Germany, consists of six spontaneous speech rating scales and five subtests: Token Test, Repetition, Written Language, Confronting Naming and Comprehension. The study aimed to describe the linguistic properties of the AAT Thai version and to investigate the test performances of the normal subjects. In this study some problems of linguistic changes in the construction of the Thai version were discussed. The results revealed that the normal subjects' performances on the test were independent of age, sex and education level. Therefore, the Thai version of AAT is applicable to the differential diagnosis of the communicative abilities of Thai aphasic patients.
Research Interests:
Despite growing evidence for an association between overweight and attention-deficit/hyperactivity disorder (ADHD), still little is known about the mechanisms underlying this relationship. Within a two (no ADHD, ADHD) × two (normal... more
Despite growing evidence for an association between overweight and attention-deficit/hyperactivity disorder (ADHD), still little is known about the mechanisms underlying this relationship. Within a two (no ADHD, ADHD) × two (normal weight, overweight) factorial design (n = 94) we tested disordered eating behaviour in a laboratory breakfast procedure as well as delay aversion (DA) in male children aged 7-15 years. While children with ADHD tended to eat above the normal level particularly at the beginning of the meal, children with overweight tended to eat above the normal level throughout the whole meal. Furthermore, preference for immediately available food was predicted by parental ratings of inattention and neuropsychological measures of DA in overweight children, and by impulsivity in children with ADHD. Our results suggest distinct neuropsychopathological pathways to abnormal eating in ADHD and overweight. Thus, children with overweight might benefit more from specialized treatment programmes that aim at improving attention functions while in children with ADHD the treatment should focus on impulsivity.
Research Interests: Decision Making, Eating Disorders, Adolescent, Comorbidity, Reward, and 12 moreOverweight, Humans, Child, Male, Feeding Behavior, Clinical Sciences, Reference Values, Cross Sectional Studies, Neurosciences, Impulsive behavior, Neuropsychological Tests, and Attention deficit disorder with hyperactivity
Permanent neuropsychological changes such as memory disturbances and depression have been found in professional divers, even in those who have never had decompression sickness. The changes are probably the result of intravascular gas... more
Permanent neuropsychological changes such as memory disturbances and depression have been found in professional divers, even in those who have never had decompression sickness. The changes are probably the result of intravascular gas bubbles insufficient to cause acute symptoms. We examined amateur divers with long histories of self-contained underwater breathing apparatus diving by magnetic resonance imaging and compared them with normal controls. Hyperintense lesions of the subcortical cerebral white matter and degenerative changes of the cervical disks were significantly more common in the divers. 27 of 52 divers had a total of 86 focal hyperintensities versus 10 of 50 controls with 14 focal hyperintensities (p < 0.01). 32 divers had at least one degenerated intravertebral disc versus 9 controls (p < 0.0001). These results suggest that amateur divers are at risk of accumulating lesions in the central nervous system and in cartilage.