tDCS

Amblyopia is a neurodevelopmental disorder of vision caused by abnormal visual experience during early childhood that is often considered to be untreatable in adulthood. Recently, it has been shown that a novel dichoptic videogame-based treatment for amblyopia can improve visual function in adult patients, at least in part, by reducing inhibition of inputs from the amblyopic eye to the visual cortex. Non-invasive anodal transcranial direct current stimulation has been shown to reduce the activity of inhibitory cortical interneurons when applied to the primary motor or visual cortex. In this double-blind, sham-controlled cross-over study we tested the hypothesis that anodal transcranial direct current stimulation of the visual cortex would enhance the therapeutic effects of dichoptic videogame-based treatment. A homogeneous group of 16 young adults (mean age 22.1 ± 1.1 years) with amblyopia were studied to compare the effect of dichoptic treatment alone and dichoptic treatment combined with visual cortex direct current stimulation on measures of binocular (stereopsis) and monocular (visual acuity) visual function. The combined treatment led to greater improvements in stereoacuity than dichoptic treatment alone, indicating that direct current stimulation of the visual cortex boosts the efficacy of dichoptic videogame-based treatment. This intervention warrants further evaluation as a novel therapeutic approach for adults with amblyopia.

Background:
Transcranial direct current stimulation (tDCS), a non-invasive method of brain stimulation, is an adjunctive research-therapy for aphasia.The concept supporting translational application of tDCS is that brain plasticity, facilitated by language intervention, can be enhanced by non-invasive brain stimulation. This study combined tDCS with an ecologically-focused behavioral approach that involved training nouns and verbs in sentences.
Method:
Participant: A 43-year-old, right-handed male with fluent-anomic aphasia who sustained a single-left-hemisphere-temporal-parietal stroke was recruited. Treatment: Instrumentation included the Soterix Medical 1×1 Device. Anodal tDCS was applied over Broca’s area. Behavioral materials included: sentence production, naming in the sentence context, and implementation of a social-conversational-discourse treatment.
Design and Procedures: The independent variable of this crossover case-study was tDCS, and the dependent variables were language and quality-of-life measures. In each session the subject received language treatment with the first 20 minutes additionally including tDCS.
Results: Performance in naming nouns and verbs in single words and sentences were obtained. Verb production in the sentence context increased after active anodal tDCS and speech-language treatment.
Conclusion: Aphasia treatment that involves naming in the sentence context in conjunction with translational application of tDCS may be a promising approach for language-recovery post stroke.

The role of prefrontal cortex (PFC) in influencing creative thinking has been investigated by many researchers who, while succeeding in proving an effective involvement of PFC, reported suggestive but sometimes conflicting results. In order to better understand the relationships between creative thinking and brain activation in a more specific area of the PFC, we explored the role of dorsolateral PFC (DLPFC). We devised an experimental protocol using transcranial direct-current stimulation (tDCS).
The study was based on a 3 (kind of stimulation: anodal vs. cathodal vs. sham)  2 (priming: divergent vs. convergent) design. Forty-five healthy adults were randomly assigned to one stimulation condition. Participants’ creativity skills were assessed using the Product Improvement subtest from the Torrance Tests of Creative Thinking (TTCT). After 20 min of tDCS stimulation, participants were presented with visual images of common objects. Half of the participants were instructed to visualize themselves using the object in an unusual way (divergent priming), whereas the other half were asked to visualize themselves while using the object in a common way (convergent priming). Priming was aimed at inducing participants to adopt different attitudes toward the creative task. Afterwards, participants were asked to describe all of the possible uses of the objects that were presented. Participants’  physiological activation was recorded using a biofeedback equipment. Results showed a significant effect of anodal stimulation that enhanced creative performance, but only after divergent priming. Participants showed lower skin temperature values after cathodal stimulation, a finding which is coherent with studies reporting that, when a task is not creative or creative thinking is not prompted, people show lower levels of arousal. Differences in individual levels of creativity as assessed by the Product Improvement test were not influential. The involvement of DLPFC in creativity has been supported, presumably in association to shift of attention modulated by priming.

Our (2014) model for the regulation of cognitive enhancement devices (CEDs) received a great deal of interest from those involved in European device regulation and from academic commentators. Further, since the publication of our recommendations, the number of manufacturers of brain stimulation devices for non-medical purposes has increased, underscoring the need for a regulatory response. In this paper, we clarify aspects of our original proposal and address additional regulatory issues beyond our original focus on the sale of devices. We begin with theoretical points pertaining to the definition of a CED and the distinction between treatment and enhancement. We then respond to practical challenges raised by the prospect of implementing our regulatory framework. Next, we address some wider societal considerations relating to users and other stakeholders. Finally, we revisit the broader regulatory context within which the various discussions are situated.

Background
Amblyopia is a neurodevelopmental disorder of vision that is associated with abnormal patterns of neural inhibition within the visual cortex. This disorder is often considered to be untreatable in adulthood due to insufficient visual cortex plasticity. There is increasing evidence that interventions which target inhibitory interactions within the visual cortex, including certain types of non-invasive brain stimulation, can improve visual function in adults with amblyopia.
Objective
We tested the hypothesis that anodal transcranial direct current stimulation (a-tDCS) would improve visual function in adults with amblyopia by enhancing the neural response to inputs from the amblyopic eye.

Methods
Thirteen adults with amblyopia participated and contrast sensitivity in the amblyopic and fellow fixing eye was assessed before, during and after a-tDCS or cathodal tDCS (c-tDCS). Five participants also completed an fMRI study designed to investigate the effect of a-tDCS on the BOLD response within the visual cortex to inputs from the amblyopic vs. the fellow fixing eye.
Results
A subgroup of 8/13 participants showed a transient improvement in amblyopic eye contrast sensitivity for at least 30 minutes after a-tDCS. fMRI measurements
3
indicated that the characteristic cortical response asymmetry in amblyopes which favours the fellow eye was reduced by a-tDCS.

Conclusions
These preliminary results suggest that a-tDCS deserves further investigation as a potential tool to enhance amblyopia treatment outcomes in adults.""""

Research has shown that direct current stimulation (tDCS) over left temporoparietal cortex – a region implicated in phonological processing – aids new word learning. The locus of this effect remains unclear since (i) experiments have not empirically separated the acquisition of phonological forms from lexical-semantic links and (ii) outcome measures have focused on learnt associations with a referent rather than phonological stability. We tested the hypothesis that left temporoparietal tDCS would strengthen the acquisition of phonological forms, even in the absence of the opportunity to acquire lexical-semantic associations. Participants were familiarised with nonwords paired with (i) photographs of concrete referents or (ii) blurred images where no clear features were visible. Nonword familiarisation proceeded under conditions of anodal tDCS and sham stimulation in different sessions. We examined the impact of these manipulations on the stability of the phonological trace in an immediate serial recall (ISR) task the following day, ensuring that any effects were due to the influence of tDCS on long-term learning and not a direct consequence of short-term changes in neural excitability. We found that only a few exposures to the phonological forms of nonwords were sufficient to enhance nonword ISR overall compared to entirely novel items. Anodal tDCS during familiarisation further enhanced the acquisition of phonological forms, producing a specific reduction in the frequency of phoneme migrations when sequences of nonwords were maintained in verbal short-term memory. More of the phonemes that were recalled were bound together as a whole correct nonword following tDCS. These data show that tDCS to left temporoparietal cortex can facilitate word learning by strengthening the acquisition of long-term phonological forms, irrespective of the availability of a concrete referent, and that the consequences of this learning can be seen beyond the learning task as strengthened phonological coherence in verbal short-term memory.

ABSTRACT There are only a few treatments available for Tourette syndrome (TS). These treatments frequently do not work in patients with moderate to severe TS [1]. Neuroimaging studies show a correlation between tics severity and increased activation over motor pathways, along with reduced activation over the control areas of the cortico-striato-thalamo-cortical circuits [2]. Moreover, the temporal pattern of tic generation suggests that cortical activation especially in the SMA precedes subcortical activation [3].