Toward unraveling reading–related modulations of tDCS–induced neuroplasticity in the human visual cortex

Stimulation using weak electrical direct currents has shown to be capable of inducing polarity-dependent diminutions or elevations in motor and visual cortical excitability. The aim of the present study was to test if reading during transcranial direct current stimulation (tDCS) is able to modify stimulation-induced plasticity in the visual cortex. Phosphene thresholds (PTs) in 12 healthy subjects were recorded before and after 10 min of anodal, cathodal, and sham tDCS in combination with reading. Reading alone decreased PTs significantly, compared to the sham tDCS condition without reading. Interestingly, after both anodal and cathodal stimulation there was a tendency toward smaller PTs. Our results support the observation that tDCS-induced plasticity is highly dependent on the cognitive state of the subject during stimulation, not only in the case of motor cortex but also in the case of visual cortex stimulation.

[1]  Walter Paulus,et al.  Manipulation of phosphene thresholds by transcranial direct current stimulation in man , 2003, Experimental Brain Research.

[2]  M. Nitsche,et al.  Partially non‐linear stimulation intensity‐dependent effects of direct current stimulation on motor cortex excitability in humans , 2013, The Journal of physiology.

[3]  M. Nitsche,et al.  External modulation of visual perception in humans , 2001, Neuroreport.

[4]  H. Onishi,et al.  Corticomotor excitability induced by anodal transcranial direct current stimulation with and without non-exhaustive movement , 2013, Brain Research.

[5]  O. Carter,et al.  Transcranial direct current stimulation: five important issues we aren't discussing (but probably should be) , 2014, Front. Syst. Neurosci..

[6]  K. Hoffmann,et al.  Direct Current Stimulation over V5 Enhances Visuomotor Coordination by Improving Motion Perception in Humans , 2004, Journal of Cognitive Neuroscience.

[7]  K. Welch,et al.  Transcranial magnetic stimulation confirms hyperexcitability of occipital cortex in migraine , 1998, Neurology.

[8]  M. Nitsche,et al.  Pharmacological approach to the mechanisms of transcranial DC-stimulation-induced after-effects of human motor cortex excitability. , 2002, Brain : a journal of neurology.

[9]  D B McCreery,et al.  Considerations for safety in the use of extracranial stimulation for motor evoked potentials. , 1987, Neurosurgery.

[10]  L. Bindman,et al.  The action of brief polarizing currents on the cerebral cortex of the rat (1) during current flow and (2) in the production of long‐lasting after‐effects , 1964, The Journal of physiology.

[11]  Martin Eimer,et al.  The neural signature of phosphene perception , 2010, Human brain mapping.

[12]  T. Kammer,et al.  Phosphene thresholds evoked with single and double TMS pulses , 2010, Clinical Neurophysiology.

[13]  B U Meyer,et al.  Magnetic stimuli applied over motor and visual cortex: influence of coil position and field polarity on motor responses, phosphenes, and eye movements. , 1991, Electroencephalography and clinical neurophysiology. Supplement.

[14]  M. Nitsche,et al.  Excitability changes induced in the human motor cortex by weak transcranial direct current stimulation , 2000, The Journal of physiology.

[15]  Walter Paulus,et al.  Transcranial direct current stimulation--update 2011. , 2011, Restorative neurology and neuroscience.

[16]  Walter Paulus,et al.  Therapeutic effects of non-invasive brain stimulation with direct currents (tDCS) in neuropsychiatric diseases , 2014, NeuroImage.

[17]  O. Creutzfeldt,et al.  Influence of transcortical d-c currents on cortical neuronal activity. , 1962, Experimental neurology.

[18]  Walter Paulus,et al.  Modulation of moving phosphene thresholds by transcranial direct current stimulation of V1 in human , 2003, Neuropsychologia.

[19]  L. Cohen,et al.  Reduction of human visual cortex excitability using 1-Hz transcranial magnetic stimulation , 2000, Neurology.

[20]  Antje Kraft,et al.  Excitability changes in the visual cortex quantified with signal detection analysis. , 2011, Restorative neurology and neuroscience.

[21]  W. Paulus,et al.  Towards unravelling task-related modulations of neuroplastic changes induced in the human motor cortex , 2008, Brain Stimulation.

[22]  M. Nitsche,et al.  Excitability changes induced in the human primary visual cortex by transcranial direct current stimulation: direct electrophysiological evidence. , 2004, Investigative ophthalmology & visual science.

[23]  S. Aurora,et al.  The Threshold for Phosphenes is Lower in Migraine , 2003, Cephalalgia : an international journal of headache.

[24]  Carlo Miniussi,et al.  Transcranial stimulation and cognition. , 2013, Handbook of clinical neurology.

[25]  E. Chronicle,et al.  Visual Cortex Excitability in Migraine With and Without Aura , 2001, Headache.

[26]  W. Byblow,et al.  Task-dependent modulation of inputs to proximal upper limb following transcranial direct current stimulation of primary motor cortex. , 2010, Journal of neurophysiology.

[27]  Walter Paulus,et al.  Induction of Late LTP-Like Plasticity in the Human Motor Cortex by Repeated Non-Invasive Brain Stimulation , 2013, Brain Stimulation.

[28]  Walter Paulus,et al.  Towards unravelling task‐related modulations of neuroplastic changes induced in the human motor cortex , 2007 .

[29]  Neri Accornero,et al.  Visual evoked potentials modulation during direct current cortical polarization , 2007, Experimental Brain Research.

[30]  B. Fierro,et al.  Modulation of visual cortical excitability in migraine with aura: effects of 1 Hz repetitive transcranial magnetic stimulation , 2002, Experimental Brain Research.

[31]  H. Siebner,et al.  Unravelling homeostatic interactions in inhibitory and excitatory networks in human motor cortex , 2012, The Journal of physiology.

[32]  H. Diener,et al.  Visual Cortex Excitability in Migraine Evaluated by Single and Paired Magnetic Stimuli , 2005, Headache.

[33]  L. Cohen,et al.  Enhanced excitability of the human visual cortex induced by short-term light deprivation. , 2000, Cerebral cortex.

[34]  A. Antal,et al.  Transcranial Direct Current Stimulation Reveals Inhibitory Deficiency In Migraine , 2007, Cephalalgia : an international journal of headache.

[35]  A. Quartarone,et al.  Long lasting effects of transcranial direct current stimulation on motor imagery , 2004, Neuroreport.

[36]  S. Brandt,et al.  Transcranial direct current stimulation affects visual perception measured by threshold perimetry , 2010, Experimental Brain Research.