Body-Mind Reader

Announcing the Body-Mind Reader, a biofeedback device that measures heart rate, heart rate variability, and a composite of these two parameters, all presented in a pleasing-to-use, attractive graphical format.

By william Bernstein, PhD

About the Body-Mind Reader

Our bodies are somewhat like cars. Cars need an accelerator, brakes, and a steering wheel. The body’s accelerator and brakes are in the autonomic nervous system. The Autonomic or Automatic nervous system uses mostly unconscious processes to regulate bodily functions like the operation of the liver, kidneys, stomach, heart and, in part, the lungs. The sympathetic part of the automatic system is the accelerator. It works to increase arousal or energy as it beats faster.

The other arm of this unconscious system is the parasympathetic part. It works to brake or control arousal. Moment to moment changes in the intervals between heart beats is called Heart Rate Variability (HRV). If HRV changes faster than it had during a baseline measurement, control is increasing.


The Body-Mind Reader is different from other Heart Rate and HRV devices in that it measures and correlates both heart rate and heart rate variability. It assesses the degree of alignment between arousal and control. This information is the feedback provided on your phone. Such feedback can teach one how to increase the alignment between these usually unconscious parts of the nervous system.

Changes in the autonomic system can be caused by changes in bodily activity and by thoughts. More positive thoughts and feeling tend to increase alignment. Thinking is the task of the conscious mind, the part that makes decisions to direct the car (the steering wheel). Thoughts connect the conscious mind to the unconscious accelerator and brakes of the body. The Body-Mind Reader can help bring unconscious processes into conscious awareness.

The Body-Mind Reader is a Do-It-Yourself project

You’ll need two things:

  1. An iPhone app: The Body-Mind Reader.
  2. A heart monitor

See the Build-a-Device page for more details.

Here are views of the Reader indicating three different alignment states:

Example A

Alignment decreasing (red).

Example B

No change in alignment from baseline (blue).

Example C

Alignment increasing (green).

The device is amazing. At first I guided the Reader by changing activity, and I noticed the color changed as soon as I formulated the intent to do something. I can see that being “in the green” is a state of mind, not necessarily linked to any particular activity, or even the extent to which that activity is burdensome or enjoyable. That’s the potential of this device: to help us get into the right state of mindfulness no matter what the task.

David M, MD. Neurologist

What Does Science Say About HRV?