title: Causal manipulation of functional connectivity in a specific neural pathway during behaviour and at rest.
abstract: Correlations in brain activity between two areas (functional connectivity) have been shown to relate to their underlying structural connections. We examine the possibility that functional connectivity also reflects short-term changes in synaptic efficacy. We demonstrate that paired transcranial magnetic stimulation (TMS) near ventral premotor cortex (PMv) and primary motor cortex (M1) with a short 8-ms inter-pulse interval evoking synchronous pre- and post-synaptic activity and which strengthens interregional connectivity between the two areas in a pattern consistent with Hebbian plasticity, leads to increased functional connectivity between PMv and M1 as measured with functional magnetic resonance imaging (fMRI). Moreover, we show that strengthening connectivity between these nodes has effects on a wider network of areas, such as decreasing coupling in a parallel motor programming stream. A control experiment revealed that identical TMS pulses at identical frequencies caused no change in fMRI-measured functional connectivity when the inter-pulse-interval was too long for Hebbian-like plasticity.
authors: Department of Experimental Psychology, Oxford University, Oxford, United Kingdom.
authors: Vanessa M
authors: VM
authors: Johnen
authors: Department of Experimental Psychology, Oxford University, Oxford, United Kingdom.
authors: Franz-Xaver
authors: FX
authors: Neubert
authors: Human Cortical Physiology and Neurorehabilitation Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States.
authors: Ethan R
authors: ER
authors: Buch
authors: Department of Experimental Psychology, Oxford University, Oxford, United Kingdom.
authors: Lennart
authors: L
authors: Verhagen
authors: Centre for Functional Magnetic Resonance Imaging of the Brain, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom.
authors: Jill X
authors: JX
authors: O'Reilly
authors: Department of Experimental Psychology, Oxford University, Oxford, United Kingdom.
authors: Rogier B
authors: RB
authors: Mars
authors: Department of Experimental Psychology, Oxford University, Oxford, United Kingdom.
authors: Matthew F S
authors: MF
authors: Rushworth
mesh_terms: D000328:Adult; D063132:Connectome; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009044:Motor Cortex; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: TMS; functional connectivity; human; motor system; neuroscience; plasticity; premotor cortex; resting-state connectivity