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, Michał
AU - Smigasiewicz, Kamila
AU - Groppa, Sergiu
AU - Siebner, Hartwig R
PY - 2010
Y1 - 2010
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
SN - 0014-4819
VL - 203
SP - 355
EP - 365
JO - Experimental Brain Research
JF - Experimental Brain Research
IS - 2
ER -