6533b7dcfe1ef96bd1271f64
RESEARCH PRODUCT
Modulation of excitatory and inhibitory circuits for visual awareness in the human right parietal cortex.
Massimiliano OliveriSara TorrieroCarlo CaltagironeGiacomo Kochsubject
Cortical excitability; Neglect; Supramodal integration; TMS; Visuospatial attention;AdultMalemedicine.medical_specialtyNeurologyVisual perceptionVisuospatial attentionmedicine.medical_treatmentCentral nervous systemMagnetics; Humans; Awareness; Neural Inhibition; Electric Stimulation; Parietal Lobe; Cognition; Photic Stimulation; Adult; Space Perception; Neuropsychological Tests; Visual Pathways; Attention; Visual Perception; Female; Functional Laterality; Male; Reaction TimePosterior parietal cortexCortical excitability Neglect Supramodal integration TMS Visuospatial attentionNeuropsychological TestsInhibitory postsynaptic potentialFunctional LateralityNOMagneticsCognitionParietal LobemedicineReaction TimeHumansAttentionVisual PathwaysNeglectBalance (ability)Settore M-PSI/02 - Psicobiologia E Psicologia FisiologicaGeneral NeuroscienceCortical excitabilityNeural InhibitionSupramodal integrationAwarenessElectric StimulationTranscranial magnetic stimulationmedicine.anatomical_structureTMSSpace PerceptionExcitatory postsynaptic potentialVisual PerceptionSettore MED/26 - NeurologiaFemalePsychologyNeurosciencePhotic Stimulationdescription
The balance of specific patterns of excitation and inhibition in critical regions of both hemispheres could be relevant in orienting attention over the extrapersonal space. In the present study a group of normal subjects had to detect small rectangular stimuli presented briefly on a computer screen in three different conditions: unilateral presentation either to left or right visual periphery or bilateral simultaneous presentation. Paired transcranial magnetic stimulation (TMS), was applied over the right parietal cortex 150 ms after the presentation of the visual stimuli with different inter-stimulus intervals (ISIs: 1, 3,5 and 10 ms). When paired TMS was applied 150 ms, but not 100 ms, after simultaneous visual presentation, the number of failures in detecting left targets increased compared to the single-pulse condition if the ISI was 3 ms; on the contrary, it decreased if the ISI was 5 ms. No effects were seen when paired pulses of the same intensity were delivered. These findings provide evidence of a supramodal-specific pattern of excitability of the right posterior parietal cortex in processing visuospatial information.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-01-01 | Experimental brain research |