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Mircea Ariel Schoenfeld - One of the best experts on this subject based on the ideXlab platform.
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effects of a single Mental Chronometry training session in subacute stroke patients a randomized controlled trial
Sports Medicine Arthroscopy Rehabilitation Therapy & Technology, 2020Co-Authors: Joachim Liepert, Jana Sturner, Imke Busching, Aida Sehle, Mircea Ariel SchoenfeldAbstract:Motor imagery training might be helpful in stroke rehabilitation. This study explored if a single session of motor imagery (MI) training induces performance changes in Mental Chronometry (MC), motor execution, or changes of motor excitability. Subacute stroke patients (n = 33) participated in two training sessions. The order was randomized. One training consisted of a Mental Chronometry task, the other training was a hand identification task, each lasting 30 min. Before and after the training session, the Box and Block Test (BBT) was fully executed and also performed as a Mental version which served as a measure of MC. A subgroup analysis based on the presence of sensory deficits was performed. Patients were allocated to three groups (no sensory deficits, moderate sensory deficits, severe sensory deficits). Motor excitability was measured by transcranial magnetic stimulation (TMS) pre and post training. Amplitudes of motor evoked potentials at rest and during pre-innervation as well as the duration of cortical silent period were measured in the affected and the non-affected hand. Pre-post differences of MC showed an improved MC after the MI training, whereas MC was worse after the hand identification training. Motor execution of the BBT was significantly improved after Mental Chronometry training but not after hand identification task training. Patients with severe sensory deficits performed significantly inferior in BBT execution and MC abilities prior to the training session compared to patients without sensory deficits or with moderate sensory deficits. However, pre-post differences of MC were similar in the 3 groups. TMS results were not different between pre and post training but showed significant differences between affected and unaffected side. Even a single training session can modulate MC abilities and BBT motor execution in a task-specific way. Severe sensory deficits are associated with poorer motor performance and poorer MC ability, but do not have a negative impact on training-associated changes of Mental Chronometry. Studies with longer treatment periods should explore if the observed changes can further be expanded. DRKS, DRKS00020355 , registered March 9th, 2020, retrospectively registered
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Mental Chronometry and Mental rotation abilities in stroke patients with different degrees of sensory deficit
Restorative Neurology and Neuroscience, 2016Co-Authors: Joachim Liepert, Imke Busching, Aida Sehle, Mircea Ariel SchoenfeldAbstract:BACKGROUND Motor imagery is used for treatment of motor deficits after stroke. Clinical observations suggested that motor imagery abilities might be reduced in patients with severe sensory deficits. This study investigated the influence of somatosensory deficits on temporal (Mental Chronometry, MC) and spatial aspects of motor imagery abilities. METHODS Stroke patients (n = 70; <6 months after stroke) were subdivided into 3 groups according to their somatosensory functions. Group 1 (n = 31) had no sensory deficits, group 2 (n = 27) had a mild to moderate sensory impairment and group 3 (n = 12) had severe sensory deficits. Patients and a healthy age-matched control group (n = 23) participated in a Mental Chronometry task (Box and Block Test, BBT) and a Mental rotation task (Hand Identification Test, HIT). MC abilities were expressed as a ratio (motor execution time-motor imagery time/motor execution time). RESULTS MC for the affected hand was significantly impaired in group 3 in comparison to stroke patients of group 1 (p = 0.006), group 2 (p = 0.005) and healthy controls (p < 0.001). For the non-affected hand MC was similar across all groups. Stroke patients had a slower BBT motor execution than healthy controls (p < 0.001), and group 1 executed the task faster than group 3 (p = 0.002). The percentage of correct responses in the HIT was similar for all groups. CONCLUSION Severe sensory deficits impair Mental Chronometry abilities but have no impact on Mental rotation abilities. Future studies should explore whether the presence of severe sensory deficits in stroke patients reduces the benefit from motor imagery therapy.
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assessment of Mental Chronometry mc in healthy subjects
Archives of Gerontology and Geriatrics, 2014Co-Authors: Johanna Greiner, Mircea Ariel Schoenfeld, Joachim LiepertAbstract:Abstract Objective : This study examined the temporal congruency between real and imagined movements and explored intermanual transfer effects in healthy subjects. Methods : Seventy-six right-handed healthy subjects were allocated to three age groups and tested with a modified version of the Box and Block Test (BBT). We focussed on two aspects. First, the BBT was evaluated with respect to its ability to assess MC. Second, we were interested whether performance of motor imagery (MI) and real execution with one hand would modify performance with the other hand. To explore MC, we measured motor execution (ME) time as the time needed to perform the BBT, and MC time as the time difference between ME and the time needed for imagination of task execution. The BBT was performed with both hands consecutively to study transfer effects from one hand to the other and then repeated with the first hand for practice effects. Results : The age group with the oldest subjects exhibited a slower BBT performance and a less precise MC than the other 2 age groups. Irrespective of the age, MC abilities could be transferred to the other hand, whereas ME only improved when repeating the task with the same hand. Conclusions : The BBT was able to demonstrate an age-related decline of dexterity and MC. Intermanual transfer of MI abilities occurred even after a single run.
Patrik Vuilleumier - One of the best experts on this subject based on the ideXlab platform.
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the influence of individual motor imagery ability on cerebral recruitment during gait imagery
Human Brain Mapping, 2014Co-Authors: Marian Van Der Meulen, Gilles Allali, Sebastian W. Rieger, Frédéric Assal, Patrik VuilleumierAbstract:r r Abstract: Motor imagery (MI) is often used in combination with neuroimaging techniques to study the cog- nitive control of gait. However, imagery ability (IA) varies widely across individuals, potentially influencing the pattern of cerebral recruitment during MI. The aim of the current study was to investigate this effect of IA on the neural correlates of gait control using functional magnetic resonance imaging (fMRI). Twenty healthy young subjects were subdivided into a good and bad imagers group, on the basis of their perform- ance on two Mental Chronometry tests. For the whole group, MI activated a bilateral network of areas highly consistent with previous studies, encompassing primary motor cortex (BA 4), supplementary motor area, and other frontal and parietal areas, anterior insula, and cerebellum. Compared to bad imagers, good imagers showed higher activation in the right BA 4, left prefrontal cortex (BA 10), right thalamus, and bilat- eral cerebellum. Good imagers thus appear better able to recruit motor areas during MI, but also activate a prefrontal executive area (BA 10), which integrates information from the body and the environment and participates in higher-order gait control. These differences were found even though the two groups did not differ in other imagery abilities according to a standard questionnaire for vividness of motor and visual im- agery. Future studies on MI should take into account these effects, and control for IA when comparing dif- ferent populations, using appropriate measures. A better understanding of the neural mechanisms that underlie MI ability is crucial to accurately evaluate locomotor skills in clinical measures and neurorehabilita- tion techniques. Hum Brain Mapp 00:000-000, 2012. V C 2012 Wiley-Periodicals, Inc.
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r Human Brain Mapping 00:000–000 (2012) r The Influence of Individual Motor Imagery Ability on Cerebral Recruitment During Gait Imagery
2014Co-Authors: Marian Van Der Meulen, Gilles Allali, Sebastian W. Rieger, Frédéric Assal, Patrik VuilleumierAbstract:Abstract: Motor imagery (MI) is often used in combination with neuroimaging techniques to study the cognitive control of gait. However, imagery ability (IA) varies widely across individuals, potentially influencing the pattern of cerebral recruitment during MI. The aim of the current study was to investigate this effect of IA on the neural correlates of gait control using functional magnetic resonance imaging (fMRI). Twenty healthy young subjects were subdivided into a good and bad imagers group, on the basis of their performance on two Mental Chronometry tests. For the whole group, MI activated a bilateral network of areas highly consistent with previous studies, encompassing primary motor cortex (BA 4), supplementary motor area, and other frontal and parietal areas, anterior insula, and cerebellum. Compared to bad imagers, good imagers showed higher activation in the right BA 4, left prefrontal cortex (BA 10), right thalamus, and bilateral cerebellum. Good imagers thus appear better able to recruit motor areas during MI, but also activate a prefrontal executive area (BA 10), which integrates information from the body and the environment and participates in higher-order gait control. These differences were found even though the two groups did not differ in other imagery abilities according to a standard questionnaire for vividness of motor and visual imagery. Future studies on MI should take into account these effects, and control for IA when comparing different populations, using appropriate measures. A better understanding of the neural mechanisms that underlie MI ability is crucial to accurately evaluate locomotor skills in clinical measures and neurorehabilitatio
Joachim Liepert - One of the best experts on this subject based on the ideXlab platform.
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effects of a single Mental Chronometry training session in subacute stroke patients a randomized controlled trial
Sports Medicine Arthroscopy Rehabilitation Therapy & Technology, 2020Co-Authors: Joachim Liepert, Jana Sturner, Imke Busching, Aida Sehle, Mircea Ariel SchoenfeldAbstract:Motor imagery training might be helpful in stroke rehabilitation. This study explored if a single session of motor imagery (MI) training induces performance changes in Mental Chronometry (MC), motor execution, or changes of motor excitability. Subacute stroke patients (n = 33) participated in two training sessions. The order was randomized. One training consisted of a Mental Chronometry task, the other training was a hand identification task, each lasting 30 min. Before and after the training session, the Box and Block Test (BBT) was fully executed and also performed as a Mental version which served as a measure of MC. A subgroup analysis based on the presence of sensory deficits was performed. Patients were allocated to three groups (no sensory deficits, moderate sensory deficits, severe sensory deficits). Motor excitability was measured by transcranial magnetic stimulation (TMS) pre and post training. Amplitudes of motor evoked potentials at rest and during pre-innervation as well as the duration of cortical silent period were measured in the affected and the non-affected hand. Pre-post differences of MC showed an improved MC after the MI training, whereas MC was worse after the hand identification training. Motor execution of the BBT was significantly improved after Mental Chronometry training but not after hand identification task training. Patients with severe sensory deficits performed significantly inferior in BBT execution and MC abilities prior to the training session compared to patients without sensory deficits or with moderate sensory deficits. However, pre-post differences of MC were similar in the 3 groups. TMS results were not different between pre and post training but showed significant differences between affected and unaffected side. Even a single training session can modulate MC abilities and BBT motor execution in a task-specific way. Severe sensory deficits are associated with poorer motor performance and poorer MC ability, but do not have a negative impact on training-associated changes of Mental Chronometry. Studies with longer treatment periods should explore if the observed changes can further be expanded. DRKS, DRKS00020355 , registered March 9th, 2020, retrospectively registered
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Mental Chronometry and Mental rotation abilities in stroke patients with different degrees of sensory deficit
Restorative Neurology and Neuroscience, 2016Co-Authors: Joachim Liepert, Imke Busching, Aida Sehle, Mircea Ariel SchoenfeldAbstract:BACKGROUND Motor imagery is used for treatment of motor deficits after stroke. Clinical observations suggested that motor imagery abilities might be reduced in patients with severe sensory deficits. This study investigated the influence of somatosensory deficits on temporal (Mental Chronometry, MC) and spatial aspects of motor imagery abilities. METHODS Stroke patients (n = 70; <6 months after stroke) were subdivided into 3 groups according to their somatosensory functions. Group 1 (n = 31) had no sensory deficits, group 2 (n = 27) had a mild to moderate sensory impairment and group 3 (n = 12) had severe sensory deficits. Patients and a healthy age-matched control group (n = 23) participated in a Mental Chronometry task (Box and Block Test, BBT) and a Mental rotation task (Hand Identification Test, HIT). MC abilities were expressed as a ratio (motor execution time-motor imagery time/motor execution time). RESULTS MC for the affected hand was significantly impaired in group 3 in comparison to stroke patients of group 1 (p = 0.006), group 2 (p = 0.005) and healthy controls (p < 0.001). For the non-affected hand MC was similar across all groups. Stroke patients had a slower BBT motor execution than healthy controls (p < 0.001), and group 1 executed the task faster than group 3 (p = 0.002). The percentage of correct responses in the HIT was similar for all groups. CONCLUSION Severe sensory deficits impair Mental Chronometry abilities but have no impact on Mental rotation abilities. Future studies should explore whether the presence of severe sensory deficits in stroke patients reduces the benefit from motor imagery therapy.
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assessment of Mental Chronometry mc in healthy subjects
Archives of Gerontology and Geriatrics, 2014Co-Authors: Johanna Greiner, Mircea Ariel Schoenfeld, Joachim LiepertAbstract:Abstract Objective : This study examined the temporal congruency between real and imagined movements and explored intermanual transfer effects in healthy subjects. Methods : Seventy-six right-handed healthy subjects were allocated to three age groups and tested with a modified version of the Box and Block Test (BBT). We focussed on two aspects. First, the BBT was evaluated with respect to its ability to assess MC. Second, we were interested whether performance of motor imagery (MI) and real execution with one hand would modify performance with the other hand. To explore MC, we measured motor execution (ME) time as the time needed to perform the BBT, and MC time as the time difference between ME and the time needed for imagination of task execution. The BBT was performed with both hands consecutively to study transfer effects from one hand to the other and then repeated with the first hand for practice effects. Results : The age group with the oldest subjects exhibited a slower BBT performance and a less precise MC than the other 2 age groups. Irrespective of the age, MC abilities could be transferred to the other hand, whereas ME only improved when repeating the task with the same hand. Conclusions : The BBT was able to demonstrate an age-related decline of dexterity and MC. Intermanual transfer of MI abilities occurred even after a single run.
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reduced upper limb sensation impairs Mental Chronometry for motor imagery after stroke clinical and electrophysiological findings
Neurorehabilitation and Neural Repair, 2012Co-Authors: Joachim Liepert, Johanna Greiner, Violetta Nedelko, Christian DettmersAbstract:Background. Motor imagery (MI) is increasingly recognized as a treatment option after stroke, but not all stroke patients are able to perform MI. Objective. To examine if severe somatosensory defic...
Eva Hofmann - One of the best experts on this subject based on the ideXlab platform.
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coercive and legitimate authority impact tax honesty evidence from behavioral and erp experiments
Social Cognitive and Affective Neuroscience, 2017Co-Authors: Katharina Gangl, Daniela M Pfabigan, Claus Lamm, Erich Kirchler, Eva HofmannAbstract:: Cooperation in social systems such as tax honesty is of central importance in our modern societies. However, we know little about cognitive and neural processes driving decisions to evade or pay taxes. This study focuses on the impact of perceived tax authority and examines the Mental Chronometry mirrored in ERP data allowing a deeper understanding about why humans cooperate in tax systems. We experiMentally manipulated coercive and legitimate authority and studied its impact on cooperation and underlying cognitive (experiment 1, 2) and neuronal (experiment 2) processes. Experiment 1 showed that in a condition of coercive authority, tax payments are lower, decisions are faster and participants report more rational reasoning and enforced compliance, however, less voluntary cooperation than in a condition of legitimate authority. Experiment 2 confirmed most results, but did not find a difference in payments or self-reported rational reasoning. Moreover, legitimate authority led to heightened cognitive control (expressed by increased MFN amplitudes) and disrupted attention processing (expressed by decreased P300 amplitudes) compared to coercive authority. To conclude, the neuronal data surprisingly revealed that legitimate authority may led to higher decision conflict and thus to higher cognitive demands in tax decisions than coercive authority.
Katharina Gangl - One of the best experts on this subject based on the ideXlab platform.
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coercive and legitimate authority impact tax honesty evidence from behavioral and erp experiments
Social Cognitive and Affective Neuroscience, 2017Co-Authors: Katharina Gangl, Daniela M Pfabigan, Claus Lamm, Erich Kirchler, Eva HofmannAbstract:: Cooperation in social systems such as tax honesty is of central importance in our modern societies. However, we know little about cognitive and neural processes driving decisions to evade or pay taxes. This study focuses on the impact of perceived tax authority and examines the Mental Chronometry mirrored in ERP data allowing a deeper understanding about why humans cooperate in tax systems. We experiMentally manipulated coercive and legitimate authority and studied its impact on cooperation and underlying cognitive (experiment 1, 2) and neuronal (experiment 2) processes. Experiment 1 showed that in a condition of coercive authority, tax payments are lower, decisions are faster and participants report more rational reasoning and enforced compliance, however, less voluntary cooperation than in a condition of legitimate authority. Experiment 2 confirmed most results, but did not find a difference in payments or self-reported rational reasoning. Moreover, legitimate authority led to heightened cognitive control (expressed by increased MFN amplitudes) and disrupted attention processing (expressed by decreased P300 amplitudes) compared to coercive authority. To conclude, the neuronal data surprisingly revealed that legitimate authority may led to higher decision conflict and thus to higher cognitive demands in tax decisions than coercive authority.