Light as part of Augmented Psychotherapy

Entering a stroboscopic light session myself after having informed myself quite extensively, I thought I knew what to expect. However, the experience turned out to exceed my expectations and left me astonished. ‘Speechless’ was the first word that came to my mind after the session. Later on, I described it as a perceptual and emotional rollercoaster. While I felt a subtle sense of anxiety arising in the beginning due to the intensity of the multidimensional, colourful and endless space of geometric patterns I found myself in, this feeling quickly turned into pure amazement. The experience was , soothing and energizing at the same time. Especially the combination of the visual experience with organic sounds followed by Tibetan bowls and choir singing made this a multisensory experience. My body felt heavy and deeply relaxed. Moreover, the experience allowed me to enter a meditative state that was deeper than everything I ever reached in meditation before. I was able to let go of control entirely and fully immerse myself in this state. The intensity and spectrum of colours I saw seemed to be beyond reality. After the 30 minute session, which subjectively felt like five minutes, I felt calm, good-humoured and energized throughout the rest of the day and simply put, grateful for this miraculous experience. –Leonie Schwarz, on her stroboscope light experience

There’s a growing research field devoted to modulating brain waves for therapeutic effect. Some psychedelics, such as DMT, have been shown to create these kinds of neuromodulations, but there are non-pharmacological means of modulating brain waves as well (1). One increasingly popular method is through flickering light, or stroboscope light application. Many clinics now offer light sessions in the context of their therapies or even call these sessions “light therapy”. And there are even “light therapy” apps which use a smartphone’s flashlight to create stroboscopic light sequences that are supposed to guide users into “altered state of consciousness between deep meditation and classic psychedelics.” So far there’s limited scientific research to support the effects of such applications of light, but what literature does exist, along with anecdotal evidence, makes it clear that this may be an accessible and effective option for increasing focus, alleviating depression and stress, improving sleep and memory, and slowing the onset of disorders like Alzheimer’s and mild cognitive impairment (2).

Brain Waves and Mental Disorders

The human brain produces neural oscillations—commonly known as “brain waves”—at different frequencies. Delta waves, at the lowest frequency (0.1-4 Hz), are associated with deep, restorative sleep and the unconscious mind; theta waves (4-7 Hz) with deep meditation and light sleep; alpha waves (7-15 Hz) with deep relaxation while eyes are closed, or during daydreaming; beta waves (15-31 Hz) with waking consciousness, alertness, and sometimes anxiety and stress; and gamma waves (31-100 Hz), being the least studied, with insight and high-level information processing (3). Activities that increase gamma waves in the brain have been shown to improve memory, information processing, problem solving ability, attention span, immunity and cognitive function, and mindfulness (4). Gamma wave therapy has also shown promise in alleviating dementia and Alzheimer’s disease, mood disorders, and other conditions (5).

It is still a mystery to neuroscientists exactly why these different levels of brain waves exist, but there has been some speculation based on the research so far: “In the 90s, neuroscientists found that ‘the distinct patterns of oscillatory activity during sleep mirrored those during a previous learning exercise. Scientists suggested that these waves could be helping to solidify memories.’” (6) It is also been suggested that brain waves can influence conscious perception (7).

What scientists do know is that specific brain wave patterns are related to certain mental disorders. For example, Parkinson’s disease has been connected to disrupted beta waves. ADHD, schizophrenia, and OCD have been tied to increases across lower frequencies (delta, theta) and decreases across higher frequencies (alpha, beta, gamma). Other conditions, however, such as PTSD and addiction, have not been tied to particular brain wave patterns. The data for ADHD has been shown to be most consistent, while data for bipolar disorder, panic disorder, and anxiety is sparse (5).

In a recent literature review on this topic, however, researchers warn: “The extreme lack of standardization across the field raises a strong caution to any clinical interpretation or application of current findings.” They also warn against using neural oscillations as markers of specific disorders: “The generally common pattern across multiple disorders is an indication that individual frequency bands or even a pattern across frequency bands does not serve as a useful measure of distinction between disorders,” they write. “It also strongly makes the case that studying individual disorders in isolation can be very misleading. For instance, a higher theta/beta ratio is considered an indicator of ADHD in children and even approved as a diagnostic marker by the FDA. However, a similarly higher theta/beta ratio would be likely for schizophrenia and OCD as well.”

Even if there’s still too little research on exactly how brain wave activity correlates with different disorders, therapies that target neural oscillations have already shown promise in human studies.

What do Stroboscope Light devices target?

Stroboscope light devices makes use of gamma waves in a process known as “gamma wave entrainment.” Gamma entrainment is the synchronization of gamma brain oscillations with an external stimulus, such as light, which occupies the same frequency. Some light devices“hypnagogic” state—one between wakefulness and sleep. These states can also be described as Flicker Induced Hallucination (FIH). Patients lie on a massage chair or daybed with their eyes closed, listening to music, while they are guided by this combination of light impulses and music and an introduction by a specialist into an altered state. There may be a demo session, a few minutes long, to prepare the patient before the proper session begins. The whole session typically lasts around thirty minutes.

How Does Stroboscope Light Work?

Over the past several years, stroboscopic light systems have made headlines for showing promise in treating Alzheimer’s disease and dementia.

In 2016, a research team at the Massachusetts Institute of Technology found that shining a flickering light into the eyes of mice at a rate of 40 flickers per second (four times as fast as a disco strobe light) triggered specialized immune cells in the mouse brain to clean up amyloid plaques, toxic proteins that lead to dementia (8). After one session, amyloid plaque reduction in the visual cortex lasted around 12 to 24 hours, but the researchers found that daily sessions led to even greater reductions. What’s more, stimulating specific parts of the brain—such as the hippocampus, which is heavily involved in memory—led to reductions of plaque in those areas. This process “shifts neurons to a less degenerative state, improving synaptic function, enhancing neuroprotective factors, and reducing DNA damage in neurons while also reducing inflammatory response in microglia,” the researchers explain. The study was reported by the BBC and The Guardian and led to the development of a string of commercial companies offering “light therapies” to the public.

One surprising finding to come out of the research is that sound can affect brain waves in similar ways, and may serve as a compliment to light sessions in the near future for reasons related to neuroanatomy: “Playing rodents a 40-hertz noise, for example, seems to cause a decrease in amyloid in the hippocampus,” writes journalist Helen Thomas in a piece for Nature, “perhaps because the hippocampus sits closer to the auditory cortex than to the visual cortex.” This finding suggests that the specific effects of a light session may vary depending on which part of the brain is stimulated.

Another promising use of strobocope light is for improving sleep cycles and treating insomnia. Researchers at the Stanford University Medical Center found that study participants who were exposed to two-millisecond-long flashes of light set off at 10-second intervals while they slept were able to prevent sleep disturbances such as jet leg much better than those who did not receive the treatment (9). The light was believed to work by triggering communication between the retina and the “circadian system” in the brain, altering the biological clock. In contrast to gamma wave entrainment, intermittent light for sleep works by targeting circadian block genes. A team at the University of Amsterdam showed to be effective in treating insomnia as well, especially at a higher intensity (10). In early 2021, researchers at the Rensselaer Polytechnic Institute in New York proposed that flickering light may be effective in treating not only Alzheimer’s disease but also mild cognitive impairment (MCI) (2). It’s important to note, however, that such research is far from extensive, and it will be some time before medical claims can be made regarding the effectiveness of this stroboscopic light application for conditions like these.

Challenges to using stroboscopic light include difficulties implementing it into a patient’s daily routine, which may result in a lack of patient adherence, but new technologies are cropping up to make it easier to integrate, such as “light therapy apps”. In fact, technologies are now being developed to help people modulate their own brain waves more generally. Neurofeedback, for example, where people learn to control their own brain waves by measuring them with an EEG and receiving audio or visual cues as feedback, is one of the simplest forms of this.


The use of stroboscope light will continue to gain popularity as a non-pharmacological means of harnessing altered states of consciousness for therapeutic benefit. Further research is expected on not only the effects but the method itself, from the type of light used (luminance, color, etc.) to the preparation and after-care process following a session.

At the OVID Clinics stroboscopic light is part of the S.A.N.D. concept. S.A.N.D. stands for serotonergic psychedelics (psilocybin, DMT, LSD, etc.) , atypical psychedelics (ketamine, MDMA, etc.), non-pharmacological methods to alter consciousness (breathwork, stroboscopic light, etc.) and digital technologies to improve the patient journey (neuromeditation, digital journaling, etc.). Stroboscopic light is used for preparing patients for substance-induced therapy sessions, e.g. with ketamine. Patients report relief, relaxation, loss of anxiety, and newfound confidence in their ability to master altered states, as well as building trust towards the psychotherapists and following ketamine sessions. For some it seems to have a “psychedelic” quality of its own with dream-like and emotionalizing effects that can become part of the psychotherapy at OVID.

At the OVID Clinics, stroboscopic light is one of several tools for learning how to navigate altered states of consciousness, training mindfulness, and observing mental, emotional and somatic effects with care and non-judgmental attention. Learn more about it in one of our OVID Clinics.

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