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The effect of 10 Hz repetitive transcranial magnetic stimulation of posterior parietal cortex on visual attention.

Dombrowe I, Juravle G, Alavash M, Gießing C, Hilgetag CC - PLoS ONE (2015)

Bottom Line: Our results were mixed.However, this effect did not reach statistical significance.Thus, although we found a trend to better performance after rTMS with task than after rTMS during rest, we could not reject the hypothesis that high frequency rTMS with task and high frequency rTMS during rest equally affect performance.

View Article: PubMed Central - PubMed

Affiliation: Department of Experimental Psychology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

ABSTRACT
Repetitive transcranial magnetic stimulation (rTMS) of the posterior parietal cortex (PPC) at frequencies lower than 5 Hz transiently inhibits the stimulated area. In healthy participants, such a protocol can induce a transient attentional bias to the visual hemifield ipsilateral to the stimulated hemisphere. This bias might be due to a relatively less active stimulated hemisphere and a relatively more active unstimulated hemisphere. In a previous study, Jin and Hilgetag (2008) tried to switch the attention bias from the hemifield ipsilateral to the hemifield contralateral to the stimulated hemisphere by applying high frequency rTMS. High frequency rTMS has been shown to excite, rather than inhibit, the stimulated brain area. However, the bias to the ipsilateral hemifield was still present. The participants' performance decreased when stimuli were presented in the hemifield contralateral to the stimulation site. In the present study we tested if this unexpected result was related to the fact that participants were passively resting during stimulation rather than performing a task. Using a fully crossed factorial design, we compared the effects of high frequency rTMS applied during a visual detection task and high frequency rTMS during passive rest on the subsequent offline performance in the same detection task. Our results were mixed. After sham stimulation, performance was better after rest than after task. After active 10 Hz rTMS, participants' performance was overall better after task than after rest. However, this effect did not reach statistical significance. The comparison of performance after rTMS with task and performance after sham stimulation with task showed that 10 Hz stimulation significantly improved performance in the whole visual field. Thus, although we found a trend to better performance after rTMS with task than after rTMS during rest, we could not reject the hypothesis that high frequency rTMS with task and high frequency rTMS during rest equally affect performance.

No MeSH data available.


Related in: MedlinePlus

Experimental design and timeline for one experimental session of the experiment.Filled lightning signs indicate the rTMS, whereas the empty signs indicate the Sham stimulation. The screen symbols represent the occurence of the visual detection task. In the stimulation phase (first 10 min) participants received either rTMS or sham stimulation while they were performing the task or resting passively. In the subsequent test phase, participants performed the task while they were receiving sham stimulation.
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pone.0126802.g001: Experimental design and timeline for one experimental session of the experiment.Filled lightning signs indicate the rTMS, whereas the empty signs indicate the Sham stimulation. The screen symbols represent the occurence of the visual detection task. In the stimulation phase (first 10 min) participants received either rTMS or sham stimulation while they were performing the task or resting passively. In the subsequent test phase, participants performed the task while they were receiving sham stimulation.

Mentions: The experimental design is outlined in Fig 1. We used a repeated measures, fully crossed factorial design. This design allowed us not only to assess the main effects, such as the difference between performance after task and performance after rest, but also the interactions among factors. The first factor (i.e. independent variable) was condition, with the levels of Task (i.e., visual detection of Gabor patches) and Rest (i.e., rest with eyes closed). For each of the conditions, participants received either 10 Hz rTMS or Sham (second factor, stimulation type), leading to four different combinations: Task with rTMS, Task with Sham, Rest with rTMS, and Rest with Sham. Each of these four combinations was tested in a separate session, with only one session tested per day. As such, participants had four appointments per experiment, with the order of the sessions counterbalanced across participants. The third factor was Gabor location with the three levels of Left, Right, and Bilateral presentation.


The effect of 10 Hz repetitive transcranial magnetic stimulation of posterior parietal cortex on visual attention.

Dombrowe I, Juravle G, Alavash M, Gießing C, Hilgetag CC - PLoS ONE (2015)

Experimental design and timeline for one experimental session of the experiment.Filled lightning signs indicate the rTMS, whereas the empty signs indicate the Sham stimulation. The screen symbols represent the occurence of the visual detection task. In the stimulation phase (first 10 min) participants received either rTMS or sham stimulation while they were performing the task or resting passively. In the subsequent test phase, participants performed the task while they were receiving sham stimulation.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4430548&req=5

pone.0126802.g001: Experimental design and timeline for one experimental session of the experiment.Filled lightning signs indicate the rTMS, whereas the empty signs indicate the Sham stimulation. The screen symbols represent the occurence of the visual detection task. In the stimulation phase (first 10 min) participants received either rTMS or sham stimulation while they were performing the task or resting passively. In the subsequent test phase, participants performed the task while they were receiving sham stimulation.
Mentions: The experimental design is outlined in Fig 1. We used a repeated measures, fully crossed factorial design. This design allowed us not only to assess the main effects, such as the difference between performance after task and performance after rest, but also the interactions among factors. The first factor (i.e. independent variable) was condition, with the levels of Task (i.e., visual detection of Gabor patches) and Rest (i.e., rest with eyes closed). For each of the conditions, participants received either 10 Hz rTMS or Sham (second factor, stimulation type), leading to four different combinations: Task with rTMS, Task with Sham, Rest with rTMS, and Rest with Sham. Each of these four combinations was tested in a separate session, with only one session tested per day. As such, participants had four appointments per experiment, with the order of the sessions counterbalanced across participants. The third factor was Gabor location with the three levels of Left, Right, and Bilateral presentation.

Bottom Line: Our results were mixed.However, this effect did not reach statistical significance.Thus, although we found a trend to better performance after rTMS with task than after rTMS during rest, we could not reject the hypothesis that high frequency rTMS with task and high frequency rTMS during rest equally affect performance.

View Article: PubMed Central - PubMed

Affiliation: Department of Experimental Psychology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Department of Computational Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

ABSTRACT
Repetitive transcranial magnetic stimulation (rTMS) of the posterior parietal cortex (PPC) at frequencies lower than 5 Hz transiently inhibits the stimulated area. In healthy participants, such a protocol can induce a transient attentional bias to the visual hemifield ipsilateral to the stimulated hemisphere. This bias might be due to a relatively less active stimulated hemisphere and a relatively more active unstimulated hemisphere. In a previous study, Jin and Hilgetag (2008) tried to switch the attention bias from the hemifield ipsilateral to the hemifield contralateral to the stimulated hemisphere by applying high frequency rTMS. High frequency rTMS has been shown to excite, rather than inhibit, the stimulated brain area. However, the bias to the ipsilateral hemifield was still present. The participants' performance decreased when stimuli were presented in the hemifield contralateral to the stimulation site. In the present study we tested if this unexpected result was related to the fact that participants were passively resting during stimulation rather than performing a task. Using a fully crossed factorial design, we compared the effects of high frequency rTMS applied during a visual detection task and high frequency rTMS during passive rest on the subsequent offline performance in the same detection task. Our results were mixed. After sham stimulation, performance was better after rest than after task. After active 10 Hz rTMS, participants' performance was overall better after task than after rest. However, this effect did not reach statistical significance. The comparison of performance after rTMS with task and performance after sham stimulation with task showed that 10 Hz stimulation significantly improved performance in the whole visual field. Thus, although we found a trend to better performance after rTMS with task than after rTMS during rest, we could not reject the hypothesis that high frequency rTMS with task and high frequency rTMS during rest equally affect performance.

No MeSH data available.


Related in: MedlinePlus