title: The effect of rTMS over the inferior parietal lobule on EEG sensorimotor reactivity differs according to self-reported traits of autism in typically developing individuals.
abstract: Previous research suggested that EEG markers of mirror neuron system activation may differ, in the normal population as a function of different levels of the autistic spectrum quotient; (AQ). The present study aimed at modulating the EEG sensorimotor reactivity induced by hand movement observation by means of repetitive transcranial magnetic stimulation (rTMS) applied to the inferior parietal lobule. We examined how the resulting rTMS modulation differed in relation to the self-reported autistic traits in the typically developing population. Results showed that during sham stimulation, all participants had significantly greater sensorimotor alpha reactivity (motor cortex-C electrodes) when observing hand movements compared to static hands. This sensorimotor alpha reactivity difference was reduced during active rTMS stimulation. Results also revealed that in the average AQ group at sham there was a significant increase in low beta during hand movement than static hand observation (pre-motor areas-FC electrodes) and that (like alpha over the C electrodes) this difference is abolished when active rTMS is delivered. Participants with high AQ scores showed no significant difference in low beta sensorimotor reactivity between active and sham rTMS during static hand or hand movement observation. These findings suggest that unlike sham, active rTMS over the IPL modulates the oscillatory activity of the low beta frequency of a distal area, namely the anterior sector of the sensorimotor cortex, when participants observe videos of static hand. Importantly, this modulation differs according to the degree of self-reported traits of autism in a typically developing population.
authors.affiliation: Centre for Integrative Neuroscience and Neurodynamics, University of Reading, Whiteknights Campus (Earley Gate), Reading RG6 6AH, United Kingdom; Centre for Brain Science, Department of Psychology, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom. Electronic address: I.Puzzo@reading.ac.uk.
authors.forename: Ignazio
authors.initials: I
authors.lastname: Puzzo
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Cooper
authors.forename: Simona
authors.initials: S
authors.lastname: Cantarella
authors.forename: Paul B
authors.initials: PB
authors.lastname: Fitzgerald
authors.forename: Riccardo
authors.initials: R
authors.lastname: Russo
mesh_terms: D000328:Adult; D001321:Autistic Disorder / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006225:Hand; D006801:Humans; D008297:Male; D059167:Mirror Neurons / Q000502:physiology; D009068:Movement; D010296:Parietal Lobe / Q000502:physiology*; D010775:Photic Stimulation; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: EEG/repetitive TMS; Human Mirror Neuron System; Sensorimotor reactivity; Traits of Autism in the normal population