MRI | DIY tDCS

Not tDCS, but TMS -Transcranial Magnetic Stimulation, another form of TES – Transcranial Electric Stimulation, that is being used both clinically (FDA approved for the treatment of depression) and as a research tool. Unlike tDCS, TMS can be of sufficient power to cause neurons to fire– imagine a finger twitching in response the the activation of the TMS device.

The video describes an experiment where researchers are attempting to improve the quality of memory encoding using TMS. The point of sharing it with you on the blog is to point out how difficult this is in fact to do. tDCS for cognitive enhancement was what initially inspired this blog, and now these six years later, I’m not sure we’re any closer to having a useful tool for cognitive enhancement of any kind, though I am reasonably confident in stating that tDCS for the treatment of depression is at least worth trying. (Other areas of research I’m more optimistic about are tDCS and Aphasia, tDCS and Parkinson’s, and tDCS for the enhancement of physical training. But in all of these the jury is still out, as there is conflicting research results.)

Note as well in the video the elaborate set up for measuring the effect of TMS in the memory study. These are often standardized tests used throughout psychology research. Unfortunately they are often costly and complicated to use. Point being that any sort of DIY cognitive enhancement experiments need to consider how effects will be measured.

Wow! Check the article for the photo showing US Army use/placement of electrodes.

They used magnetoencephalography MEG to record magnetic fields brain waves produced by sensory stimulation sound, touch and light, for example, while test subjects received TDCS. The researchers reported that TDCS gave a six-times baseline boost to the amplitude of a brain wave generated in response to stimulating a sensory nerve in the arm. The boost was not seen when mock TDCS was used, which produced a similar sensation on the scalp, but was ineffective in exciting brain tissue. The effect also persisted long after TDCS was stopped. The sensory-evoked brain wave remained 2.5 times greater than normal 50 minutes after TDCS. These results suggest that TDCS increases cerebral cortex excitability, thereby heightening arousal, increasing responses to sensory input, and accelerating information processing in cortical circuits.

Remarkably, MRI brain scans revealed clear structural changes in the brain as soon as five days after TDCS. Neurons in the cerebral cortex connect with one another to form circuits via massive bundles of nerve fibers axons buried deep below the brain’s surface in “white matter tracts.” The fiber bundles were found to be more robust and more highly organized after TDCS. No changes were seen on the opposite side of the brain that was not stimulated by the scalp electrodes.

via Amping Up Brain Function: Transcranial Stimulation Shows Promise in Speeding Up Learning: Scientific American.

DIY tDCS

Keeping Tabs On Transcranial Direct Current Stimulation

Tag Archives: MRI

Stimulation Excites the Brain to Form Better Memories | NorthwesternU

Amping Up Brain Function: Transcranial Stimulation Shows Promise in Speeding Up Learning: Scientific American