Corticospinal Excitability in the Hand Muscles is Decreased During Eye Movement with Visual Occlusion

2016 ◽  
Vol 122 (1) ◽  
pp. 238-255 ◽  
Author(s):  
Yuta Chujo ◽  
Yasutomo Jono ◽  
Keisuke Tani ◽  
Yoshifumi Nomura ◽  
Koichi Hiraoka
Author(s):  
Kouki Kato ◽  
Tetsuro Muraoka ◽  
Nobuaki Mizuguchi ◽  
Kento Nakagawa ◽  
Hiroki Nakata ◽  
...  

2013 ◽  
Vol 109 (4) ◽  
pp. 1097-1106 ◽  
Author(s):  
Hamid F. Bagce ◽  
Soha Saleh ◽  
Sergei V. Adamovich ◽  
John W. Krakauer ◽  
Eugene Tunik

We used adaptation to high and low gains in a virtual reality setup of the hand to test competing hypotheses about the excitability changes that accompany motor learning. Excitability was assayed through changes in amplitude of motor evoked potentials (MEPs) in relevant hand muscles elicited with single-pulse transcranial magnetic stimulation (TMS). One hypothesis is that MEPs will either increase or decrease, directly reflecting the effect of low or high gain on motor output. The alternative hypothesis is that MEP changes are not sign dependent but rather serve as a marker of visuomotor learning, independent of performance or visual-to-motor mismatch (i.e., error). Subjects were required to make flexion movements of a virtual forefinger to visual targets. A gain of 1 meant that the excursions of their real finger and virtual finger matched. A gain of 0.25 (“low gain”) indicated a 75% reduction in visual versus real finger displacement, a gain of 1.75 (“high gain”) the opposite. MEP increases (>40%) were noted in the tonically activated task-relevant agonist muscle for both high- and low-gain perturbations after adaptation reached asymptote with kinematics matched to veridical levels. Conversely, only small changes in excitability occurred in a control task of pseudorandom gains that required adjustments to large errors but in which learning could not accumulate. We conclude that changes in corticospinal excitability are related to learning rather than performance or error.


2012 ◽  
Vol 41 (1) ◽  
pp. 30-37 ◽  
Author(s):  
Sören Kliem* ◽  
Christoph Kröger* ◽  
Nico Bayat Sarmadi ◽  
Joachim Kosfelder
Keyword(s):  

Zusammenfassung. Theoretischer Hintergrund: Bei der Behandlung der posttraumatischen Belastungsstörung (PTBS) nach einem Typ-II-Trauma werden im klinischen Alltag gegenwärtig unterschiedliche traumabearbeitende Interventionen eingesetzt. Fragestellung: Wie werden die Verbesserungen in verschiedenen Symptombereichen (plötzliches Wiedererleben, Vermeidung, Übererregung, Dissoziation und zusätzliche Symptomatik) in Abhängigkeit von dem Einsatz unterschiedlicher traumabearbeitender Interventionen von den Behandlern retrospektiv eingeschätzt? Methode: Aus einer Umfrage unter Psychologischen Psychotherapeuten (N = 272) wurden die Fälle ausgewählt, bei denen die Therapeuten (1) ein Ereignis nannten, das einem Typ-II-Trauma zugeordnet werden konnte, und (2) angaben, traumabearbeitende Interventionen gemäß der traumafokussierenden, kognitiven Verhaltenstherapie (TF-KVT), der Methode des Eye Movement Desensitization and Reprocessing (EMDR-Methode) oder der Psychodynamisch-imaginativen Traumatherapie (PITT) durchgeführt zu haben (n = 37). Außerdem beurteilten die Therapeuten retrospektiv die Verbesserungen in den Symptombereichen zu Therapieende. Ergebnisse: Über 40% der Therapeuten gaben an, die Vorstellungsübungen bzw. Bearbeitung des Täter Introjekts gemäß der PITT eingesetzt zu haben, gefolgt von den traumabearbeitenden Interventionen der TF KVT (35.1%) und der EMDR Methode (21.6%). Die Therapeuten, die Interventionen eines der beiden zuletzt genannten Verfahren einsetzten, schätzten die Verbesserungen in den verschiedenen Symptombereichen höher ein als diejenigen, die angaben, eine Intervention gemäß der PITT durchgeführt zu haben. Schlussfolgerungen: Die retrospektiven Einschätzungen der Verbesserungen durch die Therapeuten stehen im Einklang mit den Empfehlungen der Behandlungsleitlinien zur PTBS.


2019 ◽  
Vol 24 (4) ◽  
pp. 297-311
Author(s):  
José David Moreno ◽  
José A. León ◽  
Lorena A. M. Arnal ◽  
Juan Botella

Abstract. We report the results of a meta-analysis of 22 experiments comparing the eye movement data obtained from young ( Mage = 21 years) and old ( Mage = 73 years) readers. The data included six eye movement measures (mean gaze duration, mean fixation duration, total sentence reading time, mean number of fixations, mean number of regressions, and mean length of progressive saccade eye movements). Estimates were obtained of the typified mean difference, d, between the age groups in all six measures. The results showed positive combined effect size estimates in favor of the young adult group (between 0.54 and 3.66 in all measures), although the difference for the mean number of fixations was not significant. Young adults make in a systematic way, shorter gazes, fewer regressions, and shorter saccadic movements during reading than older adults, and they also read faster. The meta-analysis results confirm statistically the most common patterns observed in previous research; therefore, eye movements seem to be a useful tool to measure behavioral changes due to the aging process. Moreover, these results do not allow us to discard either of the two main hypotheses assessed for explaining the observed aging effects, namely neural degenerative problems and the adoption of compensatory strategies.


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