Mark Tommerdahl

24 posts

What is the overall corticalmetric score?

If you are a Brain Gauge user, you've probably noticed the overall corticalmetric score. This comprehensive measure is calculated from all the tests that were taken in a single test session. If that is a sufficint explanation, then read no further.

When we first started developing cortical metrics – all the different measures collected by the Brain Gauge (and also the name of the company... we realize that can be confusing!) – we wanted to create a unique metric that could summarize the brain profile of each individual. We believe that it


Autism, GABA and the Brain Gauge: the history of our scientific efforts in the field.

The Brain Gauge methods predicted GABA deficits in autism that were later validated with medical imaging

After having many discussions with people who are interested in the Brain Gauge technology, I became increasingly aware that a vast majority assume the Brain Gauge was designed exclusively for assessing traumatic brain injury (TBI) abd concussion. Although we have received support from the Office of Naval Research for the development of the Brain Gauge as a standardized concussion tool, the development of the device began as a means for studying alterations in brain


Alzheimer’s and Diabetes: Cause or Effect?

Alzheimer’s is often called “diabetes type 3” because there appears to be a correlation between the two disorders.

After first identifying amyloid β plaques and tau tangles in the brain of a deceased patient in the early 1900’s, Alois Alzheimer was careful to not infer that these structures had caused the dementia in the patient. Until recently, most of the research (at least by drug companies) has been aimed at finding ways to reverse the accumulation, or at least stop the spread of these structures. While drugs have


The Timing Perception Measure

Timing perception is derived from your duration discrimination task. This is the test that asks “Which stimulus lasted longer?” The first trial of the task (during training) delivers a 650 msec duration stimulus to one finger and subsequently a 500 msec duration stimulus to the other (a 150 msec difference). Each time the person taking the test identifies the finger that received the longer stimulus correctly, the difference between the two durations on the next trial is reduced. Most people track down to a difference limen of 35-60 msec, and


Pain – does anyone know how to treat it?

Or maybe a better question is – Did anyone ever successfully treat it?

One of the unique things about the somatosensory system that separates it from the other sensory modalities is that there are pain receptors in the skin that project to the somatosensory cortex. All of the painful stimuli we encounter is modulated through the sense of touch. This has been well known for decades, if not centuries, and this concept did not escape medical practitioners - the idea ofremoving this part of the brain to eliminate pain surfaced in


Can HRV be used to monitor brain functions like the Brain Gauge?

Many heart medications that improve HRV have a negative impact on brain health that can be measured with the Brain Gauge.

Several people have asked us how heart rate variability (HRV) compares to the Brain Gauge. The question we keep getting is: "Is the HRV measure from my smartwatch as good of an indicator of brain health as the Brain Gauge measures?"

The short answer to this question is no, HRV and Brain Gauge measure completely different things. Heart rate variability gives a measure of the autonomic nervous


The Accuracy Measure

Lateral inhibition: using amplitude discrimination to probe the balance between excitation and inhibition
Lateral inhibition is the brain's way of improving contrast between adjacent or near-adjacent cortical areas. In the 1960s, Nobel prize winner Georg Von Bekesy postulated the idea of lateral inhibition. The basic idea was that when you deliver a stimulus, brain activity will be correlated with the stimulus site, and the surrounding areas will be inhibited or turned off. Long story short, Von Bekesy’s predictions, which were based on sensory testing, turned out to be true.


How often should you test your brain function?

Frequency of testing brain function can be analogous to weighing yourself.

The question of how frequently someone should test themselves (or be tested by a clinician) with the Brain Gauge comes up quite often. The short answer: it depends on the reason that you are testing. Many people are doing things to make their brain function better. This is a bit like doing things to lose weight. If you are on a diet and trying to lose weight by increasing physical activity as well as cutting back on the calories,


Cause or Effect? Alcohol Consumption and Farming Practices

When considering the health effects of “conventional” vs. “organic” food, the debate is usually centered around the consumer: Are there more nutrients in one or the other? Are pesticide/herbicide levels on conventional food significant enough to cause problems? Sometimes the discussion will veer towards which is more costly to the environment, or which is more efficient for feeding a growing world population. However the discussion rarely ventures to the subject of the health of the farmer growing the food, and thus applying the fertilizers, pesticides, and herbicides. But a


Treating chronic pain with tactile discrimination?

Can the Brain Gauge be used to decrease pain or improve brain function?

For many years, people have found modest success with treating different forms of chronic pain with different types of tactile stimulation (vibration, electrical stimuli, etc.). Results from those studies (and there were quite a few) are both divergent in terms of results obtained from tactile stimulation and inconclusive. In our own work, we demonstrated a reduced effect of high frequency tactile stimulation (this means we delivered 150 Hz vibration to the skin at the same time as