Inter-individual Variability
Conditions
Keywords
Transcranial electrical stimulation; random noise;, cognitive interventions; electroencephalography;, inter-individual variability; stochastic resonance;
Brief summary
Inter-individual variability in responsiveness to interventions poses great challenges for translational neuroscience, and health care in general. The investigations sought to examine the potential for high-frequency transcranial random noise stimulation (tRNS) to modulate sustained attention in a manner that was informed by individual differences in EEG indices.
Detailed description
Inter-individual variability in responsiveness to interventions poses great challenges for translational neuroscience, and health care in general. Reliable and cost- effective screening procedures that can identify individuals who are more likely to benefit from an intervention could have substantial real-world benefits. Here, the investigators sought to examine the potential for high-frequency transcranial random noise stimulation (tRNS) to modulate sustained attention in a manner that was informed by individual differences in a well-studied electrocortical marker, spontaneous theta/beta ratio. The investigators hypothesized that individuals with relatively high theta/beta ratios, putatively reflecting suboptimal cortical arousal, would be more likely to benefit from the gains in cortical excitability afforded by tRNS. Seventy-two young healthy adults were administered 1mA, 2mA and sham tRNS in a double-blind, randomised, cross-over manner, while they performed a continuous monitoring paradigm. Electroencephalography was acquired before and after each stimulation condition. This approach may constitute a feasible means of using individual differences in neurophysiology to inform predictions about outcomes from targeted cognitive interventions.
Interventions
The transcranial random noise stimulation was delivered using a StarStim device (Neuroelectrics®, Barcelona, Spain). The electrodes were encased in a pair of saline-soaked sponges (25 cm2 ), and were secured within a Neurolectrics EEG cap over right DLPFC (F4) and right IPL (P4), according to the 10-20 international EEG system. Other details are stated under the 'intervention arm' descriptions.
Sponsors
Study design
Masking description
Randomized Double-Blind
Eligibility
Inclusion criteria
\- Aged 18-35 years
Exclusion criteria
* Left-handedness * Visual impairment * History of fainting, * History of neurological or psychiatric illness, * Neurological insult * Drug or alcohol abuse * Reporting current use of anti- psychotic or anti-depressant medications
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Electroencephalography | 4 minutes | Voltage readings from the scalp |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sustained Attention performance | 20 minutes | Sustained Attention performance was defined as response time variability on a continuous monitoring paradigm |