title: Timing of spatial priming within the fronto-parietal attention network: A TMS study.
abstract: The posterior parietal cortex (PPC) and the dorsolateral prefrontal cortex (DLPFC) are known to be part of a cortical network involved in visual spatial attention. Top-down control can modulate processing at target and distractor positions over a sequence of trials, leading to positive priming at prior target positions and negative priming at prior distractor positions. In order to elucidate the exact time course of this top-down mechanism we here propose a transcranial magnetic stimulation (TMS) protocol. Single-pulses were applied over the right PPC, the right DLPFC or over the vertex (sham stimulation) at five time intervals (50, 100, 150, 200, 250 ms) after onset of a probe display during a spatial negative priming paradigm. Both suppression of the negative priming effect at a previous distractor position and enhancement of positive priming at a previous target position was found if a TMS pulse was applied 100 ms after the probe display onset either over the right DLPFC or the right PPC. We suggest that top-down mechanisms within the right fronto-parietal attention network are compromised during TMS interference in this time window.
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany. Electronic address: stefanie.kehrer@charite.de.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Kehrer
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany; Berlin Institute of Health, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Antje
authors.initials: A
authors.lastname: Kraft
authors.affiliation: Department of Psychiatry, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Stefan P
authors.initials: SP
authors.lastname: Koch
authors.affiliation: Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Kathmann
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Irlbacher
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Stephan A
authors.initials: SA
authors.lastname: Brandt
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000502:physiology; D010296:Parietal Lobe / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D013028:Space Perception / Q000502:physiology*; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: Negative priming; Positive priming; Spatial attention; Transcranial magnetic stimulation; Visual attention