Mark Tommerdahl

46 posts

The importance of detecting the barely detectible...

Following a mild concussion, individuals typically begin to perceive a sense of normalcy within 1-2 weeks. Symptoms gradually subside, and if undergoing professional assessment, patients often exhibit a return to their initial scores on standard evaluations like SCAT and ImPACT during this post-concussion period. However, the question arises: is their brain genuinely fully recovered?
Unlike a fracture that can be directly observed through an X-ray, head injuries are evaluated indirectly by gauging brain function. This comparison is akin to assessing a broken arm's condition by assessing the arm's mobility – a


New! Brain Training with the Brain Gauge

Brain training 1.0 with the Brain Gauge is no longer in beta testing though versions 2.0 and 3.0 are! If you would like to add brain training to your Brain Gauge, simply contact to get the free update.

What is Brain training?
Brain training refers to a range of cognitive exercises, activities, or programs designed to enhance and optimize various mental processes, such as memory, attention, problem-solving, and reasoning. The primary aim of brain training is to stimulate and challenge the brain's neural networks


What is Grumpy Science?

A year after we launch Grumpy Science, we decide to write about it. After all, we are a couple of curmudgeonly old guys that do whatever we want whenever we want. So what exactly is Grumpy Science? Grumpy Science is a videocast that is co-hosted by Bob Dennis and myself. It evolved from our Friday afternoon impromptu meetings that we could never bring ourselves to call “Happy Hour”. It basically morphed into “grumpy hour” in which we complained about a lot of things and then we realized that we were


Brain Gauge Origins

My first real exposure to neuroscience was in the early 1980s (I say real because I don’t count textbook and classroom exposure). After graduating with an MS in Biomedical Engineering and Mathematics, I was hired as an in-house engineer in a neurophysiological lab. In addition to developing and maintaining experimental protocols for this lab, we were also the “hub” for a multiple investigator group that was studying pain (that program project started in the 1980s and continued for 30+ years). Several different methods were used to study pain by


What's the Brain Gauge Anyways?

The short version of where the Brain Gauge came from, what it does, and how people are using it.

The Brain Gauge is a laboratory grade research tool designed to probe brain function. It is probably one of the only, if not the only, devices with superior resolution for measuring brain health that are available for the home user. Most research grade technology is only available to researchers and clinicians. The Brain Gauge, which is used by both clinicians and researchers, has been in development for 15 years and has


The greatest thing since slicing bread from my diet

Twenty years ago, I would have really benefited from having a Brain Gauge.

At a recent workshop, we were asked some important questions about the Brain Gauge scoring system:

"Can you really see a change with diet?"
"How fast do the changes appear?"

The speed at which your Brain Gauge scores change will depend on the type of lifestyle changes you are making. After beginning an elimination diet, it may be weeks or even months before the toxins have left your body and ceased impairing your


How do my Brain Gauge scores compare to everyone else's?

An introduction to the Brain Gauge scoring system
In the ProTools (or RxTools) app, your Brain Gauge metrics reflect how your brain performance compares to population averages. If you have a score of 100 for any metric, you performed as good as (or better than) healthy controls from our subject population. We calculated the mean scores for our tests through years of clinical trials.

On the other hand, if you have a low Brain Gauge score (between 0 and 70), you scored poorly on that metric's tests compared to our


Self-perception as a means of assessing brain health

Self-assessment may not be the most accurate way to monitor your brain health.

Most people monitor their cognitive function by looking at how well they are able to perform routine activities. They only start to worry about brain health once it becomes difficult to read a book, drive a car, or think creatively. Unfortunately, by that point their brain health has likely been deteriorating for weeks or even months at a rate that is imperceptible but steady. This phenomenon - the inability to detect potentially harmful changes that happen gradually


Problems with concussion testing in sports

Most currently available concussion tests rely on baseline scores. At the beginning of the season, athletes complete an assessment to establish their baseline cognitive health. When an athlete sustains a head injury or shows symptoms of a concussion, a trainer or coach administers the test again and compares the two sets of scores. If the post-injury scores are substantially lower than the baseline results, athletes are removed from play.

At first glance, this approach seems reasonable. Everyone's brain is different, so by comparing a potentially concussed individual to that individual's


Measuring Neuroinflammation

The Timing Perception measure (or Duration Discrimination) comes from the test that asks you “which stimulus lasted longer?”. This score is useful on its own, but you can gain even more insight into your brain health by comparing it to your Duration Discrimination with confound score. The difference between these two scores is based on a brain illusion - a mistake that your brain makes when comparing two sensations. But don't worry - if your brain is making this mistake, it means that it's healthy!

How the illusion is created