CONVERSATIONS BETWEEN JEFF AND HERSHEL Friends, inventors, competitors, but mostly friends

picture taken at ISNR 2006 A bit of history: Hershel was clearly the inventor of HEG. It was a Near Infrared Spectroscopy system (nir). pIR (my system) came later. Interestingly, the stimulus for each form of HEG was a “challenge”.

nirHEG Invented by Hershel, 1994 Prompted (challenged) by a colleague who found a theoretical paper on nir spectroscopy. Hershel said: “I can make that!” Originally called the “Thinking Cap” Been through refinements, but original was just as light weight and comfortable as current. One big advantage over EEG was application time. It only took a few seconds. No skin prep.

nirHEG Before that, Hershel’s main focus was multimodal physiological acquisition for feedback but also to help his wife Marjorie with her psychotherapy practice. Originally this was to give her clues as to the emotional state of the patient. Eventually it was used directly by the patient.

nirHEG The nirHEG system became integrated into his Biocomp, which was a DOS based computerized biofeedback system. This was an impressive system. With DOS, a command was a command. With Windows, a command is a “suggestion”. I miss DOS.

pirHEG Invented by Jeff, 1998 Prompted (challenged?) by Ed Sorel and Ben Perkus Because… we all wanted Hershel’s “thinking cap”, but couldn’t afford it. “Think you could make one?” Original pir headset (center) was big and heavy. Current (right) more light weight and comfortable and larger field of view. It evolved from a 7mm (mounted in a kitchen sponge) center weighted circle to a 32mm center weighted circle to a uniform 38mm by 50mm rectangle. With pir, BIGGER IS BETTER!

RSD / CRPS Before that… (1995, 1996, 1997) I was working on infrared technology for RSD, Raynaud’s, and Migraines, but the focus was peripheral thermal. Better than contact for several reasons: –Speed, accuracy, no need to touch RSD backfired badly. Horrible!! But verified that IR could be used to train vascular behavior. Increased blood flow made it worse.

pirHEG Raynaud’s and Migraines responded peripherally (the “gold standard” at the time). Tried reducing cerebral blood flow for migraines but did not work. After aware of Hershel’s system to increase cerebral blood flow I tried it and it worked with migraines.

pirHEG Once the system started working ok, I tried multiple sites around the head, based on infrared images. Poor outcomes. Best effects at Fpz. In addition, Fpz eliminated the potential for messing someone up by training the wrong side of the brain.

HEG / EEG Although both forms of HEG are a bit different technically and operationally, they share an immunity to the eye roll artifact that can be a problem with EEG feedback.

TECHNICAL COMPARISON pirHEG Passive, 7 to 14 microns Measuring thermal metabolic waste – correlate of metabolic activity Large target area (1.5x2 inch) Frontal lobe Response similar to mental effort Response different to emotional activation nirHEG Active, color of blood Measuring color of blood – correlate of metabolic activity Small focus target area Frontal lobe Response similar to mental effort Response different to emotional activation

TECHNICAL COMPARISON

pirHEG Yoda – relaxed focus A bit like “open focus” Behavior change can be based on a shift in dominance. Does not need to be explained by “growth”. But also forcing flipping back and forth between incompatible brain states. No signal gain anticipated If it occurs it is not relevant nirHEG Weight lifting – exercise model Brain growth required for “real” progress, measured over multiple sessions. Unidirectional goal – signal gain pre/post session.

EARLY TREATMENT FOCUS MANY SIMILARITIES BUT SOME DIFFERENCES pirHEG Migraine headaches Depression Rage Attentional Disorders nirHEG Toxic encephalopathy Cortical blindness Autism Head injury There is an unanswered question here: To what extent were these differences due to our personality differences as opposed to the technology differences?

PHILOSOPHICAL COMPARISON Behavioral – psychological perspective with a technical flair Skeptical of fMRI, PET, SPECT, neuropsychological testing “Yes, but what if…” Technical – engineering perspective with a psychological flair Trust data such as fMRI, PET, SPECT, neuropsychological testing Data equals “proof”

So, Hershel would call me with an observation… And I would say “Are you sure?” (Actually that’s why he would call – because he knew I would raise questions he had not considered.) Especially for issues surrounding psychopathology ADHD Depression Etc.

One issue we disagreed on was the issue of brain laterality. Hershel digested every fMRI study he could find, and targeted nir sessions based on the assumption that the brain should be left hemisphere dominant. Although Hershel and I both started out targeting the center of the forehead, we both moved towards targeting very specific sites. He based his site selection on known anatomical functions, while I based my site selection on infrared images. We diverged at this point because Hershel moved on to greater site specificity while I found that no matter how much tracking of deficit areas I did, Fpz produced better results.

We both wandered around the head at various points in time, but Hershel continued while I moved back to the center of the forehead. Note: Brodmann areas 9, 10, and 11 make up the pfc. This area is considered the executive control center and is largely inhibitory.

My concern/response was that lots of folks in our population have messed up brains with ambiguous or reversed laterality. That meant the the control circuits he was targeting could be reversed! Note: this is my own personal soapbox issue, and applies to lateralized EEG protocols as well.

In addition, the issue of processing networks began to creep into the EEG field. Hershel would alternately embrace these concepts and then flip back to a localization/control system frame of reference. These are not incompatible, but all these concepts can get confusing when trying to take them all into consideration at the same time.

Some examples: Depression tends to correlate with low activity levels around Fp1, except with reverse lateralized people, in which case it correlates with low activity levels around Fp2.

14yo female, depression, right handed, left lateralized for language.

20yo female, depression, left handed, reverse lateralized for language.

How to tell language lateralization? Handedness for motor activities is only somewhat suggestive. Solution: Watch to see which hand the person is “talking” with. Not perfect but much safer than the Wada test.

PERSONAL Our wives were our soulmates for over 40 years. Sadly both developed serious fatal illnesses. We spent hours and hours on the phone with each other, just talking about our wives. Marjorie passed away first, my wife about a year later. One day I had told Hershel that I thought my wife was in remission, Hershel broke down and cried – tears of happiness. This was a side of Hershel that very few people had the opportunity to experience.