What is a Ganzfeld effect? The Ganzfeld (German for “complete/full field”) effect happens when the sensory system is steadily overloaded with a uniform signal. For example, a uniform, steady and all-encompassing soft light to the eyes will cause a “loss of vision”. This happens because, essentially, there is no change in the signal going to the brain, so the brain stops processing the signal.

Ganzfeld experimenter

The Ganzfeld is interesting because it is a simple, yet effective tool which provides a mild form of sensory deprivation. And sensory deprivation is interesting because the effects include hallucinations, relaxation and time distortion – it’s like turning on the screen saver in your brains.

Mild sensory deprivation through the Ganzfeld effect gives mild effects. The sensory deprivation effect can be deepened, but be advised that for prolonged total sensory deprivation there will also be some adverse effects, for example loss of identity, apathy and depression.

Anyway, to enhance the effect, the basic idea is to extend the Ganzfeld idea to other senses than vision. For example, you can use earphones with white noise sound for hearing, thick gloves on hands to prevent touch sensations, and so on. In such a multimodal Ganzfeld (MMGF), dreamlike, pseudo-hallucinatory images are frequently induced.

While trying out the Ganzfeld with a big blank wall in a darkened room, for a short period of time I saw myself in a snowy parking lot. After that I saw as if I was sitting on the ground at street level and people were walking by – I could see legs of people walking by.

Experimenting with the Ganzfeld Effect

A simple “Ganzfeld device” is easy to build; first, cut a uniform colour ping-pong ball in two. Make the cut slightly wavy to fit the eye socket better. File the sharp edges down a bit e.g. with a nail file. Now, place the ball halves over the eyes. Operating the device is likewise easy: while wearing the apparatus and keeping the eyes open, shine a light source at the ping-pong balls. The visual field should appear to be of an uniform colour and intensity. Stay still and just relax your eyes while staring at the uniform visual field.

You can also achieve a kind of Ganzfeld effect by staring at a stationary point for some time. The eyes should not move. Eventually the vision will begin to fade out, and will return once the eyes are moved enough. Starting to see an afterimage is a good sign, but it also means your eyes are moving. It may help to try to reduce the rate of blinking. Also, it might be easier to experiment with a large area of uniform colour, such as a wall.

Extending the Ganzfeld Effect to Do Basic Sensory Deprivation

If you want to block your aural senses, put earplugs into your ears, or play noise for example with a portable music player. To avoid background noises, e.g. traffic noises from outside, sports earphones which go inside the ears, or more expensive active noise cancellation earphones work well. If you use earplugs, you’ll be hearing a silent noise-like whoosh sound which is the sound of circulating blood – like music from your body.

Here are 60 second loopable clips of white, pink and brown noise for your experiments.

To block the touch sense of your hands, you can wear gloves, or cross the fingers of the left and right hands, or place the hands inside each other, and so on – find a configuration which feels comfortable. After some time, the hands will feel like a uniform warm mass and you cannot feel your individual fingers.

For some real sensory deprivation, you can check around if there’s a spa with a “sensory deprivation tank” in your area.

Uses of Ganzfeld

The Ganzfeld effect can be used in combination with other methods which do not require inputs from the senses. For instance, a Ganzfeld effect could be desireable during visualization or relaxation practices to reduce distractions and to deepen the state of visualization and relaxation.

Also, the mild hallucinations might be interesting to experiment with. Since it’s hard to command dreams to appear at will, Ganzfeld is a good alternative for gaining better access to your brain’s capabilities.