Neglect-like visual exploration behaviour after theta burst transcranial magnetic stimulation of the right posterior parietal cortex

• Published in: The European journal of neuroscience 2008-04, Vol.27 (7), p.1809-1813
• Main Authors: Nyffeler, Thomas, Cazzoli, Dario, Wurtz, Pascal, Lüthi, Mathias, Von Wartburg, Roman, Chaves, Silvia, Déruaz, Anouk, Hess, Christian W., Müri, René M.
• Format: Article
• Language: English
• Subjects: Adult; Exploratory Behavior - physiology; Eye Movements - physiology; Female; human; Humans; Male; Middle Aged; Parietal Lobe - physiology; Perceptual Disorders - etiology; Perceptual Disorders - physiopathology; Photic Stimulation - methods; Psychomotor Performance - physiology; saccades; theta burst stimulation; Theta Rhythm - methods; TMS; Transcranial Magnetic Stimulation - adverse effects; Transcranial Magnetic Stimulation - methods; visual fixations; Visual Perception - physiology
• ISSN: 0953-816X; 1460-9568
• DOI: 10.1111/j.1460-9568.2008.06154.x

The right posterior parietal cortex (PPC) is critically involved in visual exploration behaviour, and damage to this area may lead to neglect of the left hemispace. We investigated whether neglect‐like visual exploration behaviour could be induced in healthy subjects using theta burst repetitive transcranial magnetic stimulation (rTMS). To this end, one continuous train of theta burst rTMS was applied over the right PPC in 12 healthy subjects prior to a visual exploration task where colour photographs of real‐life scenes were presented on a computer screen. In a control experiment, stimulation was also applied over the vertex. Eye movements were measured, and the distribution of visual fixations in the left and right halves of the screen was analysed. In comparison to the performance of 28 control subjects without stimulation, theta burst rTMS over the right PPC, but not the vertex, significantly decreased cumulative fixation duration in the left screen‐half and significantly increased cumulative fixation duration in the right screen‐half for a time period of 30 min. These results suggest that theta burst rTMS is a reliable method of inducing transient neglect‐like visual exploration behaviour.