Transcranial direct current stimulation - what is the evidence for its efficacy and safety?

Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, has emerged in the past decade as a useful investigative and therapeutic technique. A number of recent studies suggest that tDCS is safe and may be efficacious in the treatment of a variety of psychiatric and neurological disorders, including major depressive disorder, chronic neuropathic pain, and stroke. More evidence is necessary, however, before it can be recommended for general clinical application

Assessing Legislative Interest for a Sugar-Sweetened Beverage Tax in a Midwestern State

BACKGROUND: This study sought to ascertain the opinions of members of the Kansas Legislature regarding pending sugar-sweetened beverage taxation legislation, including perceptions that such a tax would generate revenue or be associated with personal sugar-sweetened beverage consumption habits. METHODS: This study utilized a cross-sectional survey design and was conducted by administering an electronic or telephone survey of the 2010-2011 Kansas Legislature. Publicly-listed contact information for the 165 members in both chambers of the 2010-2011 Kansas Legislature was obtained. State legislators were invited via e-mail, telephone, or both to complete the survey. The main outcome measure was the degree of agreement or disagreement with the idea of sugar-sweetened beverage taxation. RESULTS: Seventy-eight legislators (47.3%) responded. Of these, 90.5% disagreed or strongly disagreed with taxation of sugar-sweetened beverages, and 86.5% disagreed or strongly disagreed with taxation of sugar-sweetened beverages if generated funds were set aside to subsidize healthy choices. Party affiliation, geographic area represented, and personal consumption of sugar-sweetened behaviors were not associated significantly with legislators’ opinions of sugar-sweetened beverage taxation. CONCLUSIONS: The majority of respondents in the Kansas Legislature reported opposing a sugar-sweetened beverage tax. While some respondents identified obesity as a problem, taxation of sugar-sweetened beverages was not a favorable option among Kansas legislators

Assessing neurophysiological changes associated with combined transcranial direct current stimulation and cognitive-emotional training for treatment-resistant depression

Transcranial direct current stimulation (tDCS), a form of non‐invasive brain stimulation, is a promising treatment for depression. Recent research suggests that tDCS efficacy can be augmented using concurrent cognitive‐emotional training (CET). However, the neurophysiological changes associated with this combined intervention remain to be elucidated. We therefore examined the effects of tDCS combined with CET using electroencephalography (EEG). A total of 20 participants with treatment‐resistant depression took part in this open‐label study and received 18 sessions over 6 weeks of tDCS and concurrent CET. Resting‐state and task‐related EEG during a 3‐back working memory task were acquired at baseline and immediately following the treatment course. Results showed an improvement in mood and working memory accuracy, but not response time, following the intervention. We did not find significant effects of the intervention on resting‐state power spectral density (frontal theta and alpha asymmetry), time–frequency power (alpha event‐related desynchronisation and theta event‐related synchronisation) or event‐related potentials (P2 and P3 components). We therefore identified little evidence of neurophysiological changes associated with treatment using tDCS and concurrent CET, despite significant improvements in mood and near‐transfer effects of cognitive training to working memory accuracy. Further research incorporating a sham‐controlled group may be necessary to identify the neurophysiological effects of the intervention

Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

Objective: Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenenace and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task. Methods: 41 depressed participants and 41 age- and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz). Results: MDD participants had prolonged response times and more positive P3 amplitudes relative to controls. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty. Conclusions: Depression is associated with generalized psychomotor slowing of working memory processes, as well as compensatory hyperactivity in frontal regions.Significance: These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable workig memory performance to controls.</p

Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

OBJECTIVE: Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenance and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task. METHODS: 41 depressed participants and 41 age and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz). RESULTS: MDD participants had prolonged response times and more positive frontal P3 amplitudes (i.e., Fz) relative to controls, mainly in the most difficult 2-back condition. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty. CONCLUSIONS: Depression is associated with generalized psychomotor slowing of working memory processes, and may involve compensatory hyperactivity in frontal and parietal regions. SIGNIFICANCE: These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable working memory performance to controls

Estimating the Quality of Electroconvulsive Therapy Induced Seizures Using Decision Tree and Fuzzy Inference System Classifiers

© 2018 IEEE. Electroconvulsive therapy (ECT) is an effective and widely used treatment for major depressive disorder, in which a brief electric current is passed through the brain to trigger a brief seizure. This study aims to identify seizure quality rating by utilizing a set of seizure parameters. We used 750 ECT EEG recordings in this experiment. Four seizure related parameters, (time of slowing, regularity, stereotypy and post-ictal suppression) are used as inputs to two classifiers, decision tree and fuzzy inference system (FIS), to predict seizure quality ratings. The two classifiers produced encouraging results with error rate of 0.31 and 0.25 for FIS and decision tree, respectively. The classification results show that the four seizure parameters provide relevant information about the rating of seizure quality. Automatic scoring of seizure quality may be beneficial to clinicians working in this field

Effects of High-Definition Transcranial Direct Current Stimulation (HD-tDCS) of the Intraparietal Sulcus and Dorsolateral Prefrontal Cortex on Working Memory and Divided Attention

Objective: There is a need to elucidate the underlying neural mechanisms subserving working memory and divided attention functioning. Recent neuroimaging studies provide evidence for anatomical co-localization of both functions. In the present study we used a functional intervention, whereby we applied a novel type of focalised, non-invasive brain stimulation, High-Definition transcranial Direct Current Stimulation (HD-tDCS), to the regions subserving these processes, the left intraparietal sulcus (IPS) and left dorsolateral prefrontal cortex (LDLPFC). Our aim was therefore to modulate activity in these regions using HD-tDCS and thereby assess their relevance for working memory, divided attention and their shared sub-processes.Method: 78 participants were evenly randomized to one of three conditions in a single blind, parallel group study design. Anodal or sham HD-tDCS was applied to either the left IPS or LDLPFC while participants completed a verbal working memory task, a divided attention task, and two tasks measuring subcomponents of working memory (updating and maintenance).Results: Focalised stimulation of the IPS and LDLPFC did not significantly modulate performance compared to sham stimulation. However, moderate effect sizes were obtained for at least one HD-tDCS condition relative to sham for all tasks, warranting further research into the functional importance of the IPS in subserving these abilities.Conclusions: The current results may be useful for informing future tDCS studies for modulating working memory and divided attention functioning