title: Rhythmic modulation of visual contrast discrimination triggered by action.
abstract: Recent evidence suggests that ongoing brain oscillations may be instrumental in binding and integrating multisensory signals. In this experiment, we investigated the temporal dynamics of visual-motor integration processes. We show that action modulates sensitivity to visual contrast discrimination in a rhythmic fashion at frequencies of about 5 Hz (in the theta range), for up to 1 s after execution of action. To understand the origin of the oscillations, we measured oscillations in contrast sensitivity at different levels of luminance, which is known to affect the endogenous brain rhythms, boosting the power of alpha-frequencies. We found that the frequency of oscillation in sensitivity increased at low luminance, probably reflecting the shift in mean endogenous brain rhythm towards higher frequencies. Importantly, both at high and at low luminance, contrast discrimination showed a rhythmic motor-induced suppression effect, with the suppression occurring earlier at low luminance. We suggest that oscillations play a key role in sensory-motor integration, and that the motor-induced suppression may reflect the first manifestation of a rhythmic oscillation.
authors.affiliation: Department of Neuroscience, Psychology, Pharmacology and Child Health, University of Florence, 50135 Florence, Italy Department of Translational Research on New Technologies in Medicines and Surgery, University of Pisa, Via San Zeno 31, 56123 Pisa, Italy Institute of Neuroscience, National Research Council (CNR), 56124 Pisa, Italy.
authors.forename: Alessandro
authors.identifier: 0000-0002-9713-1300
authors.initials: A
authors.lastname: Benedetto
authors.affiliation: Department of Human Movement, Social and Health Sciences, University of Rome, 'Foro Italico', Pizza Lauro De Bosis 15, 00135, Rome, Italy IRCCS Santa Lucia Foundation, Rome, Italy.
authors.forename: Donatella
authors.identifier: 0000-0002-4890-6931
authors.initials: D
authors.lastname: Spinelli
authors.affiliation: Department of Translational Research on New Technologies in Medicines and Surgery, University of Pisa, Via San Zeno 31, 56123 Pisa, Italy Scientific Institute Stella Maris, Viale del Tirreno 331, 56018 Calambrone, Pisa, Italy concetta@in.cnr.it.
authors.forename: M Concetta
authors.identifier: 0000-0002-1025-0316
authors.initials: MC
authors.lastname: Morrone
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D015350:Contrast Sensitivity; D005260:Female; D006801:Humans; D010507:Periodicity; D011597:Psychomotor Performance; D013997:Time Factors; D014796:Visual Perception; D055815:Young Adult
keywords: action and perception; contrast discrimination; endogenous rhythm; sensory–motor integration; visual oscillations