hubert dinse - Academia.edu (original) (raw)
Papers by hubert dinse
eneuro, 2021
Although we use our visual and tactile sensory systems interchangeably for object recognition on ... more Although we use our visual and tactile sensory systems interchangeably for object recognition on a daily basis, little is known about the mechanism underlying this ability. This study examined how 3D shape features of objects form two congruent and interchangeable visual and tactile perceptual spaces in healthy male and female participants. Since active exploration plays an important role in shape processing, a virtual reality environment was used to visually explore 3D objects called digital embryos without using the tactile sense. In addition, during the tactile procedure, blindfolded participants actively palpated a 3D-printed version of the same objects with both hands. We first demonstrated that the visual and tactile perceptual spaces were highly similar. We then extracted a series of 3D shape features to investigate how visual and tactile exploration can lead to the correct identification of the relationships between objects. The results indicate that both modalities share th...
<p>Mean values±SD of the gait parameters print area (A), lengths of the print (C), stride-l... more <p>Mean values±SD of the gait parameters print area (A), lengths of the print (C), stride-lengths (B) and track-widths (D) for the young (black) and the aged rats (red), * p<0.01. (A+C): In contrast to the prints obtained from the forepaws (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0003399#pone-0003399-g004" target="_blank">Fig. 4</a>), the limb-specific parameters print area and the lengths of the prints of the hindpaw were significantly increased in old animals. (B+D): As in the forepaw (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0003399#pone-0003399-g004" target="_blank">Fig. 4</a>), for the global parameters we found decreasing stride-lengths and increasing track-widths for the hindpaw in the aged animals.</p
Nature Communications, 2019
Cognition and perception are closely coupled to alpha power, but whether there is a link between ... more Cognition and perception are closely coupled to alpha power, but whether there is a link between alpha power and perceptual learning efficacy is unknown. Here we show that somatosensory alpha power can be successfully up- and down-regulated with short-term neurofeedback training, which in turn controls subsequent tactile perceptual learning. We find that neurofeedback-induced increases in alpha power lead to enhanced learning, whereas reductions in alpha power impede learning. As a consequence, interindividual learning variability is substantially reduced. No comparable impact is observed for oscillatory power in theta, beta, and lower gamma frequency bands. Our results demonstrate that high pre-learning alpha levels are a requirement for reaching high learning efficiency. These data provide further evidence that alpha oscillations shape the functional architecture of the brain network by gating neural resources and thereby modulating levels of preparedness for upcoming processing.
Research article Differential effects of tactile high- and low-frequency stimulation on tactile d... more Research article Differential effects of tactile high- and low-frequency stimulation on tactile discrimination in human subjects
Neuroscience for Psychologists, 2020
Neuron, 2003
Pleger et al., 2001). From a number of animal studies, the importance of temporally correlated in... more Pleger et al., 2001). From a number of animal studies, the importance of temporally correlated inputs has been assumed to play a key role in mediating plastic changes
Klinische Neurophysiologie, 2010
PLoS Biology, 2005
Repetitive transcranial magnetic stimulation (rTMS) is increasingly used to investigate mechanism... more Repetitive transcranial magnetic stimulation (rTMS) is increasingly used to investigate mechanisms of brain functions and plasticity, but also as a promising new therapeutic tool. The effects of rTMS depend on the intensity and frequency of stimulation and consist of changes of cortical excitability, which often persists several minutes after termination of rTMS. While these findings imply that cortical processing can be altered by applying current pulses from outside the brain, little is known about how rTMS persistently affects learning and perception. Here we demonstrate in humans, through a combination of psychophysical assessment of two-point discrimination thresholds and functional magnetic resonance imaging (fMRI), that brief periods of 5 Hz rTMS evoke lasting perceptual and cortical changes. rTMS was applied over the cortical representation of the right index finger of primary somatosensory cortex, resulting in a lowering of discrimination thresholds of the right index finger. fMRI revealed an enlargement of the right index finger representation in primary somatosensory cortex that was linearly correlated with the individual rTMS-induced perceptual improvement indicative of a close link between cortical and perceptual changes. The results demonstrate that repetitive, unattended stimulation from outside the brain, combined with a lack of behavioral information, are effective in driving persistent improvement of the perception of touch. The underlying properties and processes that allow cortical networks, after being modified through TMS pulses, to reach new organized stable states that mediate better performance remain to be clarified.
NeuroReport, 1992
We report that the response of neurons in rat somatosensory cortex to tactile stimulation consist... more We report that the response of neurons in rat somatosensory cortex to tactile stimulation consists of two components, a short-latency response and an oscillatory response, observable as up to 8 peaks in the post-stimulus-time-histogram with interpeak intervals in the order of 100 ms (10 Hz). While the first component is always stimulus locked, the second component is strictly stimulus-locked only when elicited from the resting state: once started, the oscillations are only weakly affected by further stimulation. This implies generally that the question of stimulus locking of oscillatory response components is not a yes/no question. Instead, the concept of dynamic coupling is shown to adequately capture the different limit cases. We present a simple dynamic model that exemplifies this point.
European Journal of Neuroscience, 2004
Musician's brains constitute an interesting model for neuroplasticity. Imaging studies demonstrat... more Musician's brains constitute an interesting model for neuroplasticity. Imaging studies demonstrated that sensorimotor cortical representations are altered in musicians, which was assumed to arise from the development of skilled performance. However, the perceptual consequences of the cortical changes remain elusive. Here we ask whether cortical reorganization induced by professional musical skill training is paralleled by the evolution of other, unrelated perceptual abilities. We therefore studied psychophysically tactile spatial acuity as an indirect marker of cortical changes in professional pianists and non-musician control subjects using a simultaneous two-point discrimination paradigm. We show that long-lasting piano practising resulted in lower spatial discrimination thresholds in comparison to non-musicians. In musicians, individual discrimination thresholds were linearly correlated with the daily training duration, indicating a direct link between tactile acuity and the degree of piano practising. To investigate whether the superior acuity in pianists is subject to further improvement, we used a Hebbian stimulation protocol of tactile coactivation known to improve spatial tactile acuity. Three hours of coactivation further reduced their discrimination thresholds. The coactivation-induced gain in pianists was signi®cantly larger in comparison to control subjects and correlated with the years of heavy daily practising (>3 h/day), but not with the total years including casual playing. Our results suggest that despite already high-level performance in pianists, Hebbian learning was more effective in musicians than in controls. This implies stronger capacities for plastic reorganization and points to enhanced learning abilities implicating a form of meta-plasticity in professional pianists.
Archives of Physical Medicine and Rehabilitation, 2009
Objective: To explore the effectiveness of repetitive electrical stimulation referred to here as ... more Objective: To explore the effectiveness of repetitive electrical stimulation referred to here as tactile coactivation and to improve sensory discrimination and function in the most involved hand of a person recovering from stroke. Design: Pre-experimental 1-group (nϭ4) design with multiple measures. Setting: Outpatient stroke treatment center. Participants: Subjects with 6 months or longer poststroke with self-reported sensory loss and a mild motor impairment in the most involved hand. Intervention: Electrical stimulation (coactivation) of the fingers of the involved hand for 90 minutes 4 days a week for 6 weeks. Main Outcome Measures: Primary-dependent measures included touch threshold, tactile acuity, haptic object recognition, motor tapping task, pegboard activities, and functional tasks from the Wolf Motor Function Test. Results: Posttreatment assessments revealed improvements in sensory discrimination and motor task performance in all subjects in varying degrees; these results held 4 weeks posttreatment. Conclusions: The type of repetitive electrical stimulation or tactile coactivation used in this study has not been explored previously in subjects with sensory loss caused by stroke. The results of this pilot study suggest that coactivation may have the potential to be a useful therapeutic modality for this population.
Neural plasticity, 2010
Age-related changes occur on all stages of the human somatosensory pathway, thereby deteriorating... more Age-related changes occur on all stages of the human somatosensory pathway, thereby deteriorating tactile, haptic, and sensorimotor performance. However, recent studies show that age-related changes are not irreversible but treatable through peripheral stimulation paradigms based on neuroplasticity mechanisms. We here applied repetitive electric stimulation (rES) to the fingers on a bi-weekly basis for 4 weeks to induce enduring amelioration of age-related changes in healthy individuals aged 60-85 years. Tactile, haptic, and motor performance gradually improved over time of intervention. After termination of rES, tactile acuity recovered to baseline within 2 weeks, while the gains in haptic and motor performance were preserved for 2 weeks. Sham stimulation showed no comparable changes. Our data indicate that age-related decline of sensorimotor performance can be ameliorated by rES and can be stabilized by the repeated application. Thus, long-term application of rES appears as a prim...
Copyright © 2011 Tobias Kalisch et al. This is an open access article distributed under the Creat... more Copyright © 2011 Tobias Kalisch et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. As life expectancy continues to rise, in the future there will be an increasing number of older people prone to falling. Accordingly, there is an urgent need for comprehensive testing of older individuals to collect data and to identify possible risk factors for falling. Here we use a low-cost force platform to rapidly assess deficits in balance under various conditions. We tested 21 healthy older adults and 24 young adults during static stance, unidirectional and rotational displacement of their centre of pressure (COP). We found an age-related increase in postural sway during quiet standing and a reduction of maximal COP displacement in unidirectional and rotational displacement tests. Our data show that even low-cost computerized ...
We assume that the visual system serves for orientation in space, recognition of objects and the ... more We assume that the visual system serves for orientation in space, recognition of objects and the interpretation of scenes and scene sequences. This task breaks up into a series of partially interdependent subproblems which are solved by some 13–15 usually retinotopically organized areas. So far it has not been possible to correlate functions and areas unequivocally. One reason for this could be the inadequacy of the questions posed as a basis for experiments. However, we think it more likely that correlating a function with an area is, as a rule, inadmissible since the degree of the coupling in the whole system does not permit a simple divsion. Rather the type and degree of coupling determine the separation or integration of “elementary units”. It follows that co-operation between subsystems is an essential aspect. The data available to us from neurophysiological, neuroanatomic and behavioral physiological findings is insufficient to analyse such a system: they ensure neither the complete observability nor the complete controllability of the systems. So one is forced to use model comparison for analysis. Depending on the type of data, we use three models which complement each other to order the data and predict results which can be experimentally verified.
Scientific Reports
The levels of the gonadal hormones estradiol and progesterone vary throughout the menstrual cycle... more The levels of the gonadal hormones estradiol and progesterone vary throughout the menstrual cycle thereby affecting cognition, emotion, mood, and social behaviour. However, how these hormones modulate the balance of neural excitation and inhibition, which crucially regulate processing and plasticity, is not fully understood. We here used paired-pulse stimulation to investigate in healthy humans the action of low and high estradiol and progesterone on intracortical inhibition in somatosensory (SI) and visual cortex (V1). We found that paired-pulse suppression in both SI and VI depended on estradiol. During high estradiol levels, paired-pulse suppression was significantly reduced. No comparable effects were found for progesterone, presumably due to a confounding effect of estradiol. Also, no hormone level-depending effects were observed for single-pulse evoked SEPs (somatosensory evoked potentials) and VEPs (visual evoked potentials) indicating a specific hormonal action on intracorti...
Frontiers in Human Neuroscience
Behavioral and Brain Sciences
Single cell receptive field dynamics characterized by highly complicated spatio-temporal activity... more Single cell receptive field dynamics characterized by highly complicated spatio-temporal activity distributions observable during sensory information processing transforms into much simpler spatio-temporal activity pattern at a population level, indicating a qualitative transformational step of time-variant processing from microscopic to mesoscopic levels. As these dynamics are subject to significant modifications during learning, dynamic information processing is in a permanent state of use-dependent fluctuations.
Behavioral and Brain Sciences
Modified action, either artificially induced or occurring naturally during life-span, alters orga... more Modified action, either artificially induced or occurring naturally during life-span, alters organization and processing of primary somatosensory cortex, thereby serving as a predictor of age-related changes. These findings, together with the interconnectedness between motor-sensory systems and temporally-distributed processing across hierarchical levels, throws into question a sharp division between early perception and cognition, and suggest that composite codes of perception and action might not be limited to higher areas.
BMC Neurology
Background: Repetitive sensory stimulation (RSS) adapts the timing of stimulation protocols used ... more Background: Repetitive sensory stimulation (RSS) adapts the timing of stimulation protocols used in cellular studies to induce synaptic plasticity. In healthy subjects, RSS leads to widespread sensorimotor cortical reorganization paralleled by improved sensorimotor behavior. Here, we investigated whether RSS reduces sensorimotor upper limb impairment in patients with subacute stroke more effectively than conventional therapy. Methods: A single-blinded sham-controlled clinical trial assessed the effectiveness of RSS in treating sensorimotor deficits of the upper limbs. Patients with subacute unilateral ischemic stroke were randomly assigned to receive standard therapy in combination with RSS or with sham RSS. Patients were masked to treatment allocation. RSS consisted of intermittent 20 Hz electrical stimulation applied on the affected hand for 45 min/day, 5 days per week, for 2 weeks, and was transmitted using custom-made stimulation-gloves with built-in electrodes contacting each fingertip separately. Before and after the intervention, we assessed light-touch and tactile discrimination, proprioception, dexterity, grip force, and subtasks of the Jebsen Taylor hand-function test for the non-affected and the affected hand. Data from these quantitative tests were combined into a total performance index serving as primary outcome measure. In addition, tolerability and side effects of RSS intervention were recorded. Results: Seventy one eligible patients were enrolled and randomly assigned to receive RSS treatment (n = 35) or sham RSS (n = 36). Data of 25 patients were not completed because they were transferred to another hospital, resulting in n = 23 for each group. Before treatment, sensorimotor performance between groups was balanced (p = 0.237). After 2 weeks of the intervention, patients in the group receiving standard therapy with RSS showed significantly better restored sensorimotor function than the control group (standardized mean difference 0.57; 95% CI-0.013-1.16; p = 0.027) RSS treatment was superior in all domains tested. Repetitive sensory stimulation was well tolerated and accepted, and no adverse events were observed.
eneuro, 2021
Although we use our visual and tactile sensory systems interchangeably for object recognition on ... more Although we use our visual and tactile sensory systems interchangeably for object recognition on a daily basis, little is known about the mechanism underlying this ability. This study examined how 3D shape features of objects form two congruent and interchangeable visual and tactile perceptual spaces in healthy male and female participants. Since active exploration plays an important role in shape processing, a virtual reality environment was used to visually explore 3D objects called digital embryos without using the tactile sense. In addition, during the tactile procedure, blindfolded participants actively palpated a 3D-printed version of the same objects with both hands. We first demonstrated that the visual and tactile perceptual spaces were highly similar. We then extracted a series of 3D shape features to investigate how visual and tactile exploration can lead to the correct identification of the relationships between objects. The results indicate that both modalities share th...
<p>Mean values±SD of the gait parameters print area (A), lengths of the print (C), stride-l... more <p>Mean values±SD of the gait parameters print area (A), lengths of the print (C), stride-lengths (B) and track-widths (D) for the young (black) and the aged rats (red), * p<0.01. (A+C): In contrast to the prints obtained from the forepaws (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0003399#pone-0003399-g004" target="_blank">Fig. 4</a>), the limb-specific parameters print area and the lengths of the prints of the hindpaw were significantly increased in old animals. (B+D): As in the forepaw (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0003399#pone-0003399-g004" target="_blank">Fig. 4</a>), for the global parameters we found decreasing stride-lengths and increasing track-widths for the hindpaw in the aged animals.</p
Nature Communications, 2019
Cognition and perception are closely coupled to alpha power, but whether there is a link between ... more Cognition and perception are closely coupled to alpha power, but whether there is a link between alpha power and perceptual learning efficacy is unknown. Here we show that somatosensory alpha power can be successfully up- and down-regulated with short-term neurofeedback training, which in turn controls subsequent tactile perceptual learning. We find that neurofeedback-induced increases in alpha power lead to enhanced learning, whereas reductions in alpha power impede learning. As a consequence, interindividual learning variability is substantially reduced. No comparable impact is observed for oscillatory power in theta, beta, and lower gamma frequency bands. Our results demonstrate that high pre-learning alpha levels are a requirement for reaching high learning efficiency. These data provide further evidence that alpha oscillations shape the functional architecture of the brain network by gating neural resources and thereby modulating levels of preparedness for upcoming processing.
Research article Differential effects of tactile high- and low-frequency stimulation on tactile d... more Research article Differential effects of tactile high- and low-frequency stimulation on tactile discrimination in human subjects
Neuroscience for Psychologists, 2020
Neuron, 2003
Pleger et al., 2001). From a number of animal studies, the importance of temporally correlated in... more Pleger et al., 2001). From a number of animal studies, the importance of temporally correlated inputs has been assumed to play a key role in mediating plastic changes
Klinische Neurophysiologie, 2010
PLoS Biology, 2005
Repetitive transcranial magnetic stimulation (rTMS) is increasingly used to investigate mechanism... more Repetitive transcranial magnetic stimulation (rTMS) is increasingly used to investigate mechanisms of brain functions and plasticity, but also as a promising new therapeutic tool. The effects of rTMS depend on the intensity and frequency of stimulation and consist of changes of cortical excitability, which often persists several minutes after termination of rTMS. While these findings imply that cortical processing can be altered by applying current pulses from outside the brain, little is known about how rTMS persistently affects learning and perception. Here we demonstrate in humans, through a combination of psychophysical assessment of two-point discrimination thresholds and functional magnetic resonance imaging (fMRI), that brief periods of 5 Hz rTMS evoke lasting perceptual and cortical changes. rTMS was applied over the cortical representation of the right index finger of primary somatosensory cortex, resulting in a lowering of discrimination thresholds of the right index finger. fMRI revealed an enlargement of the right index finger representation in primary somatosensory cortex that was linearly correlated with the individual rTMS-induced perceptual improvement indicative of a close link between cortical and perceptual changes. The results demonstrate that repetitive, unattended stimulation from outside the brain, combined with a lack of behavioral information, are effective in driving persistent improvement of the perception of touch. The underlying properties and processes that allow cortical networks, after being modified through TMS pulses, to reach new organized stable states that mediate better performance remain to be clarified.
NeuroReport, 1992
We report that the response of neurons in rat somatosensory cortex to tactile stimulation consist... more We report that the response of neurons in rat somatosensory cortex to tactile stimulation consists of two components, a short-latency response and an oscillatory response, observable as up to 8 peaks in the post-stimulus-time-histogram with interpeak intervals in the order of 100 ms (10 Hz). While the first component is always stimulus locked, the second component is strictly stimulus-locked only when elicited from the resting state: once started, the oscillations are only weakly affected by further stimulation. This implies generally that the question of stimulus locking of oscillatory response components is not a yes/no question. Instead, the concept of dynamic coupling is shown to adequately capture the different limit cases. We present a simple dynamic model that exemplifies this point.
European Journal of Neuroscience, 2004
Musician's brains constitute an interesting model for neuroplasticity. Imaging studies demonstrat... more Musician's brains constitute an interesting model for neuroplasticity. Imaging studies demonstrated that sensorimotor cortical representations are altered in musicians, which was assumed to arise from the development of skilled performance. However, the perceptual consequences of the cortical changes remain elusive. Here we ask whether cortical reorganization induced by professional musical skill training is paralleled by the evolution of other, unrelated perceptual abilities. We therefore studied psychophysically tactile spatial acuity as an indirect marker of cortical changes in professional pianists and non-musician control subjects using a simultaneous two-point discrimination paradigm. We show that long-lasting piano practising resulted in lower spatial discrimination thresholds in comparison to non-musicians. In musicians, individual discrimination thresholds were linearly correlated with the daily training duration, indicating a direct link between tactile acuity and the degree of piano practising. To investigate whether the superior acuity in pianists is subject to further improvement, we used a Hebbian stimulation protocol of tactile coactivation known to improve spatial tactile acuity. Three hours of coactivation further reduced their discrimination thresholds. The coactivation-induced gain in pianists was signi®cantly larger in comparison to control subjects and correlated with the years of heavy daily practising (>3 h/day), but not with the total years including casual playing. Our results suggest that despite already high-level performance in pianists, Hebbian learning was more effective in musicians than in controls. This implies stronger capacities for plastic reorganization and points to enhanced learning abilities implicating a form of meta-plasticity in professional pianists.
Archives of Physical Medicine and Rehabilitation, 2009
Objective: To explore the effectiveness of repetitive electrical stimulation referred to here as ... more Objective: To explore the effectiveness of repetitive electrical stimulation referred to here as tactile coactivation and to improve sensory discrimination and function in the most involved hand of a person recovering from stroke. Design: Pre-experimental 1-group (nϭ4) design with multiple measures. Setting: Outpatient stroke treatment center. Participants: Subjects with 6 months or longer poststroke with self-reported sensory loss and a mild motor impairment in the most involved hand. Intervention: Electrical stimulation (coactivation) of the fingers of the involved hand for 90 minutes 4 days a week for 6 weeks. Main Outcome Measures: Primary-dependent measures included touch threshold, tactile acuity, haptic object recognition, motor tapping task, pegboard activities, and functional tasks from the Wolf Motor Function Test. Results: Posttreatment assessments revealed improvements in sensory discrimination and motor task performance in all subjects in varying degrees; these results held 4 weeks posttreatment. Conclusions: The type of repetitive electrical stimulation or tactile coactivation used in this study has not been explored previously in subjects with sensory loss caused by stroke. The results of this pilot study suggest that coactivation may have the potential to be a useful therapeutic modality for this population.
Neural plasticity, 2010
Age-related changes occur on all stages of the human somatosensory pathway, thereby deteriorating... more Age-related changes occur on all stages of the human somatosensory pathway, thereby deteriorating tactile, haptic, and sensorimotor performance. However, recent studies show that age-related changes are not irreversible but treatable through peripheral stimulation paradigms based on neuroplasticity mechanisms. We here applied repetitive electric stimulation (rES) to the fingers on a bi-weekly basis for 4 weeks to induce enduring amelioration of age-related changes in healthy individuals aged 60-85 years. Tactile, haptic, and motor performance gradually improved over time of intervention. After termination of rES, tactile acuity recovered to baseline within 2 weeks, while the gains in haptic and motor performance were preserved for 2 weeks. Sham stimulation showed no comparable changes. Our data indicate that age-related decline of sensorimotor performance can be ameliorated by rES and can be stabilized by the repeated application. Thus, long-term application of rES appears as a prim...
Copyright © 2011 Tobias Kalisch et al. This is an open access article distributed under the Creat... more Copyright © 2011 Tobias Kalisch et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. As life expectancy continues to rise, in the future there will be an increasing number of older people prone to falling. Accordingly, there is an urgent need for comprehensive testing of older individuals to collect data and to identify possible risk factors for falling. Here we use a low-cost force platform to rapidly assess deficits in balance under various conditions. We tested 21 healthy older adults and 24 young adults during static stance, unidirectional and rotational displacement of their centre of pressure (COP). We found an age-related increase in postural sway during quiet standing and a reduction of maximal COP displacement in unidirectional and rotational displacement tests. Our data show that even low-cost computerized ...
We assume that the visual system serves for orientation in space, recognition of objects and the ... more We assume that the visual system serves for orientation in space, recognition of objects and the interpretation of scenes and scene sequences. This task breaks up into a series of partially interdependent subproblems which are solved by some 13–15 usually retinotopically organized areas. So far it has not been possible to correlate functions and areas unequivocally. One reason for this could be the inadequacy of the questions posed as a basis for experiments. However, we think it more likely that correlating a function with an area is, as a rule, inadmissible since the degree of the coupling in the whole system does not permit a simple divsion. Rather the type and degree of coupling determine the separation or integration of “elementary units”. It follows that co-operation between subsystems is an essential aspect. The data available to us from neurophysiological, neuroanatomic and behavioral physiological findings is insufficient to analyse such a system: they ensure neither the complete observability nor the complete controllability of the systems. So one is forced to use model comparison for analysis. Depending on the type of data, we use three models which complement each other to order the data and predict results which can be experimentally verified.
Scientific Reports
The levels of the gonadal hormones estradiol and progesterone vary throughout the menstrual cycle... more The levels of the gonadal hormones estradiol and progesterone vary throughout the menstrual cycle thereby affecting cognition, emotion, mood, and social behaviour. However, how these hormones modulate the balance of neural excitation and inhibition, which crucially regulate processing and plasticity, is not fully understood. We here used paired-pulse stimulation to investigate in healthy humans the action of low and high estradiol and progesterone on intracortical inhibition in somatosensory (SI) and visual cortex (V1). We found that paired-pulse suppression in both SI and VI depended on estradiol. During high estradiol levels, paired-pulse suppression was significantly reduced. No comparable effects were found for progesterone, presumably due to a confounding effect of estradiol. Also, no hormone level-depending effects were observed for single-pulse evoked SEPs (somatosensory evoked potentials) and VEPs (visual evoked potentials) indicating a specific hormonal action on intracorti...
Frontiers in Human Neuroscience
Behavioral and Brain Sciences
Single cell receptive field dynamics characterized by highly complicated spatio-temporal activity... more Single cell receptive field dynamics characterized by highly complicated spatio-temporal activity distributions observable during sensory information processing transforms into much simpler spatio-temporal activity pattern at a population level, indicating a qualitative transformational step of time-variant processing from microscopic to mesoscopic levels. As these dynamics are subject to significant modifications during learning, dynamic information processing is in a permanent state of use-dependent fluctuations.
Behavioral and Brain Sciences
Modified action, either artificially induced or occurring naturally during life-span, alters orga... more Modified action, either artificially induced or occurring naturally during life-span, alters organization and processing of primary somatosensory cortex, thereby serving as a predictor of age-related changes. These findings, together with the interconnectedness between motor-sensory systems and temporally-distributed processing across hierarchical levels, throws into question a sharp division between early perception and cognition, and suggest that composite codes of perception and action might not be limited to higher areas.
BMC Neurology
Background: Repetitive sensory stimulation (RSS) adapts the timing of stimulation protocols used ... more Background: Repetitive sensory stimulation (RSS) adapts the timing of stimulation protocols used in cellular studies to induce synaptic plasticity. In healthy subjects, RSS leads to widespread sensorimotor cortical reorganization paralleled by improved sensorimotor behavior. Here, we investigated whether RSS reduces sensorimotor upper limb impairment in patients with subacute stroke more effectively than conventional therapy. Methods: A single-blinded sham-controlled clinical trial assessed the effectiveness of RSS in treating sensorimotor deficits of the upper limbs. Patients with subacute unilateral ischemic stroke were randomly assigned to receive standard therapy in combination with RSS or with sham RSS. Patients were masked to treatment allocation. RSS consisted of intermittent 20 Hz electrical stimulation applied on the affected hand for 45 min/day, 5 days per week, for 2 weeks, and was transmitted using custom-made stimulation-gloves with built-in electrodes contacting each fingertip separately. Before and after the intervention, we assessed light-touch and tactile discrimination, proprioception, dexterity, grip force, and subtasks of the Jebsen Taylor hand-function test for the non-affected and the affected hand. Data from these quantitative tests were combined into a total performance index serving as primary outcome measure. In addition, tolerability and side effects of RSS intervention were recorded. Results: Seventy one eligible patients were enrolled and randomly assigned to receive RSS treatment (n = 35) or sham RSS (n = 36). Data of 25 patients were not completed because they were transferred to another hospital, resulting in n = 23 for each group. Before treatment, sensorimotor performance between groups was balanced (p = 0.237). After 2 weeks of the intervention, patients in the group receiving standard therapy with RSS showed significantly better restored sensorimotor function than the control group (standardized mean difference 0.57; 95% CI-0.013-1.16; p = 0.027) RSS treatment was superior in all domains tested. Repetitive sensory stimulation was well tolerated and accepted, and no adverse events were observed.