TY - JOUR

T1 - The left visual-field advantage in rapid visual presentation is amplified rather than reduced by posterior-parietal rTMS

AU - Verleger, Rolf

AU - Möller, Friderike

AU - Kuniecki, Michal

AU - Smigasiewicz, Kamila

AU - Groppa, Sergiu

AU - Siebner, Hartwig R

PY - 2010/6/1

Y1 - 2010/6/1

N2 - In the present task, series of visual stimuli are rapidly presented left and right, containing two target stimuli, T1 and T2. In previous studies, T2 was better identified in the left than in the right visual field. This advantage of the left visual field might reflect dominance exerted by the right over the left hemisphere. If so, then repetitive transcranial magnetic stimulation (rTMS) to the right parietal cortex might release the left hemisphere from right-hemispheric control, thereby improving T2 identification in the right visual field. Alternatively or additionally, the asymmetry in T2 identification might reflect capacity limitations of the left hemisphere, which might be aggravated by rTMS to the left parietal cortex. Therefore, rTMS pulses were applied during each trial, beginning simultaneously with T1 presentation. rTMS was directed either to P4 or to P3 (right or left parietal cortex) either as effective or as sham stimulation. In two experiments, either one of these two factors, hemisphere and effectiveness of rTMS, was varied within or between participants. Again, T2 was much better identified in the left than in the right visual field. This advantage of the left visual field was indeed modified by rTMS, being further increased by rTMS to the left hemisphere rather than being reduced by rTMS to the right. It may be concluded that superiority of the right hemisphere in this task implies that this hemisphere is less irritable by external interference than the left hemisphere.

AB - In the present task, series of visual stimuli are rapidly presented left and right, containing two target stimuli, T1 and T2. In previous studies, T2 was better identified in the left than in the right visual field. This advantage of the left visual field might reflect dominance exerted by the right over the left hemisphere. If so, then repetitive transcranial magnetic stimulation (rTMS) to the right parietal cortex might release the left hemisphere from right-hemispheric control, thereby improving T2 identification in the right visual field. Alternatively or additionally, the asymmetry in T2 identification might reflect capacity limitations of the left hemisphere, which might be aggravated by rTMS to the left parietal cortex. Therefore, rTMS pulses were applied during each trial, beginning simultaneously with T1 presentation. rTMS was directed either to P4 or to P3 (right or left parietal cortex) either as effective or as sham stimulation. In two experiments, either one of these two factors, hemisphere and effectiveness of rTMS, was varied within or between participants. Again, T2 was much better identified in the left than in the right visual field. This advantage of the left visual field was indeed modified by rTMS, being further increased by rTMS to the left hemisphere rather than being reduced by rTMS to the right. It may be concluded that superiority of the right hemisphere in this task implies that this hemisphere is less irritable by external interference than the left hemisphere.

KW - Adult

KW - Analysis of Variance

KW - Attention

KW - Brain Mapping

KW - Female

KW - Functional Laterality

KW - Humans

KW - Male

KW - Parietal Lobe

KW - Photic Stimulation

KW - Psychomotor Performance

KW - Reaction Time

KW - Transcranial Magnetic Stimulation

KW - Visual Fields

KW - Visual Perception

U2 - 10.1007/s00221-010-2237-z

DO - 10.1007/s00221-010-2237-z

M3 - Journal article

C2 - 20401472

VL - 203

SP - 355

EP - 365

JO - Experimental Brain Research

JF - Experimental Brain Research

SN - 0014-4819

IS - 2

ER -