Brain cells (actually all cells) communicate through electrical impulses. If there is insufficient impulse generation between neurons, or if the timing of impulses is too fast or too slow to be meaningful, then people experience consequences ranging from seizures, depression, and autism to anxiety, sleep disorders, and ADHD. Fisher Behavior recommends stimulation technologies to assist the brain in finding balance in amount or timing of its signals. CES, pEMF, and AVE are types of "entrainment" devices. They are like metronomes for the music of the brain. Your brain responds to timed stimulation, just as you respond automatically to the beat of your favorite music. Of these devices, tDCS is not pulsed. tDCS just gives the brain a little extra energy to get its work done. (So does CES, but it is also pulsed.) A little boost is especially useful when the brain is producing weak signals due to metabolic (energy production) issues, or tissue injury, in brain cells.
Fisher Behavior recommends home use of tDCS, CES, and pEMF technologies when the brain map so indicates.
The prestigious Johns Hopkins Department of Psychiatry and Behavioral Sciences uses Brain Stimulation technologies as a specialty area. Here is their explanation and rationale for use of tDCS. "Transcranial direct current stimulation (tDCS) is a non-invasive, painless brain stimulation treatment that uses direct electrical currents to stimulate specific parts of the brain. A constant, low intensity current is passed through two electrodes placed over the head which modulates neuronal activity. There are two types of stimulation with tDCS: anodal and cathodal stimulation. Anodal stimulation acts to excite neuronal activity while cathodal stimulation inhibits or reduces neuronal activity. Although tDCS is still an experimental form of brain stimulation, it potentially has several advantages over other brain stimulation techniques. It is cheap, non-invasive, painless and safe. It is also easy to administer and the equipment is easily portable. The most common side effect of tDCS is a slight itching or tingling on the scalp. Several studies suggest it may be a valuable tool for the treatment of neuropsychiatric conditions such as depression, anxiety, Parkinson’s disease, and chronic pain. Research has also demonstrated cognitive improvement in some patients undergoing tDCS. Currently, tDCS is not an FDA-approved treatment. Our neurology colleagues use brain stimulation to address a variety of conditions, including traumatic brain injury (TBI) and stroke, and for addressing symptoms related to: language disorders, movement disorders, impaired cognition, and chronic pain." tDCS is recommended for problems with frontal lobes or for low-energy brain map results.
Audiovisual Entrainment (AVE) - also called Audiovisual Stimulation (AVS) - has been in use since the 1930s, but can be traced to the 1800s. As it's name suggests, AVE uses rhythmic pulses of light and sound to help the brain establish a beneficial rhythm. When areas of the brain communicate, they send coordinated signals. But if two areas are sending and receiving signals with different timing, then the message may never get through. A deep brain structure called the thalamus is the brain's drummer, its metronome. When healthy, it provides the brain with global, coordinated rhythms. AVE is used when the thalamus fails to generate a single, strong, background rhythm. AVE is used for insomnia, for problems with focus and attention, for relaxation, and even for what is called top-down chronic pain. Sometimes AVE is used to treat a brain that has developmental trauma because, due to early threat conditions, that brain never became healthy enough to develop a strong background rhythm. As for the safety of AVE, there is one study, done in 1955, that argues against the use of AVE in seizure patients. This makes sense because seizures are a state of hypercoherence (the brain waves are too strongly coordinated). AVE is recommended when it the beneficial background alpha rhythm lacks strength, or when sleep is disordered. Studies have shown efficacy for cognitive improvement in school children.
Dr. Lila Massoumi, MD is Chairperson of the Caucus on Complementary, Alternative, and Integrative Medicine of the American Psychiatric Association. In the Carlat Report, this physician talks about the use of Cranio-Electric Stimulation (CES) devices to treat anxiety and insomnia, depression, and some pain syndromes. CES has been researched since the 1960s, resulting in hundreds of peer-reviewed studies for safety and efficacy. The FDA has cleared CES treatment for anxiety, insomnia, depression and some chronic pain syndromes. Because of their long safety record, all new devices have grandfathered FDA approval. CES is used to help people who have relied on benzodiazepines or other sleeping medications, or to reduce the anxiety that keeps them awake at night. Emily Deans, MD, is a psychiatrist who uses CES devices to help people tolerate withdrawal. According to Dr. Deans, fMRI shows that CES decreases cortical activity and increases serotonin and beta-endorphins in the central nervous system. When CES is set to the clear and calm rhythm of alpha brainwaves, brain maps (QEEG) show that CES decreases deep sleep delta brain waves and increases relaxation alpha waves associated with meditation and the beginning stage of sleep. Alpha is associated with well-being. CES devices can be set at other frequencies for various issues, including mitigation of proteins associated with Alzheimer's. CES is not a feedback technology, but rather is an "entrainment" technology. CES is recommended when there are sleep or anxiety problems or when brain injury or diabetes prevent adequate levels of brain signaling.
Pulsed Electromagnetic Frequency stimulation (pEMF) belongs to a group of biomagnetic therapies that deliver "neuroelectromagnetic pulses" to the body. You may have heard that EMF is detrimental, however that is referring to cell towers and microwaves which give off very high frequency signals (in Gigahertz). pEMF is a low frequency (in hertz) weaker version of repetitive Transcranial Electromagnetic Stimulation (rTMS). rTMS is FDA approved for treatment of depression, OCD (and more to come). rTMS is painful and has to be administered by an MD. pEMF devices are generally handheld devices that deliver a small fraction of the pulsed electromagnetic energy approved for rTMS. pEMF therapy is a painless treatment -- also called subthreshold that is known for pain relief (analgesia) and for treatment of inflammatory conditions. It earned FDA approval in the early 1980s to help with repair of "nonunion" bone fractures. in 2015, the FDA reclassified pEMF devices from Class 3 to Class 2 status. In 2017, the first over-the-counter device was approved by the FDA. pEMF devices have been studied for knee osteoarthritis, depression, postoperative pain, and musculoskeletal pain. This form of therapy is recommended when a brain map indicates inflammatory conditions in the brain.