Microsoft word - hemoencephalography

Hemoencephalography (HEG)
As so often happens in science, the development of new instrumentation has opened a new field.
The new field of hemoencephalography (HEG) studies cortical hemodynamics: vascularity,blood volume, oxygenation, metabolism or temperature in real time. This study is developinginformation vital to the well being the cerebral cortex.
The new instrument, the near infrared spectrophotometer (NIRS), was first introduced by Jobsisin 1977, a student of Professor Britton Chance at the University of Pennsylvania.
Using these new instruments, NIRS, has led to the discovery that the vascular variables, bloodoxygenation and flow, are voluntarily controllable. Voluntary control is leading to furtherdiscoveries of HEG’s usefulness as a therapeutic exercise agent in neurofeedback. The discoveryof voluntary control further led Jeff Carmen to explore a new use for an old instrument,measurement and feedback of cerebral temperature with an infrared thermometer.
In this paper Hershel Toomim and Jeff Carmen present case material derived from their workwith HEG. Each has described a successful and an unsuccessful case The purpose of thisjuxtaposition is to help build criteria for successful handling of cases more difficult to treat withEEG.
HEG has the advantage relative to EEG of being almost immune to muscle artifact. Eyemovement, for example, has no effect on the indications. This opens the frontal and prefrontalcortex to treatments very difficult with EEG. Relaxation is no longer necessary to protect thefeedback signal from contamination with muscle artifact. Removal of the relaxation requirementallows more usual styles of intense concentration as required to motivate and enhance the effectsof the HEG exercise training.
A salient advantages of HEG over EEG is the ease of learning control. The first part of onesession usually suffices. The remarkable clarity of the HEG feedback signal simplifies learningand supplies a simple criterion for successful sessions. A 10% increase of HEG average readingsin a 10 minute trial has proven to be a good, easily measured rule of thumb for therapeuticeffectiveness. The goal, thus established, leads to more effective efforts on the part of the trainee.
New HEG instruments supply useful feedback signals from any placement. Targeting treatmentto the affected brain area now becomes simple and fosters more efficient treatments. Treatmentsno longer must rely on connectivity of cortical areas to bring the treatment to inaccessible brainareas. No longer must we move to the light to look for the brass ring lost in the dark. This factorprovides greater efficiency and helps provide for shorter less expensive treatments.
The simplicity of HEG application, and training evaluation makes home training practical.
Measurement of gains with the new home based T.O.V.A. PC computer program empowers thehome trainer to communicate effectively with a supervising professional.
The targeting possibilities of HEG makes the SPECT or QEEG coherence studies extremelyvaluable aids in defining the hypoperfused brain areas most likely to underly brain dysfunction.
SPECT, QEEG, vascularity and HEG form a science foundation for neurofeedback and make theprocess understandable to the professional and layman alike.
A recent comparison of SPECT with QEEG promises to make QEEG a less expensive route toeffective targeting of the therapeutic exercise.
I, Hershel Toomim, find the label “ADD” unhelpful in determining the course of therapy for itsbearer. I find targeted treatments to those brain areas most involved in the functions limitingthe child’s development. more effective than my earlier work with generalized EEG. HEG makestargeted treatments convenient. Figure 1 shows the vascular effectiveness on Fpz of training atCz to be approximately 10% as effective at Fpz as similar training at Fpz.
The technique of HEG rests on extensive investigation of the optical properties of cerebral tissue.
The scientific and medical literature on NIRS contains more than 200 peer reviewed papers inpremier journals of science and medicine. The field of optical examination through the skull ofliving cerebral cortices was introduced by Jobsis (Jobsis FF 1977), a student at the time ofProfessor Britton Chance of the University of Pennsylvania, showed that radiant energy, light orheat, easily penetrates the skull and carries information about cerebral tissue oxygenation.
From that modest start extensive work through the years has made great progress. The NIRSinstrumentation has since been brought to a high state of development by Prof. Chance, hisstudents and collaborators. For a review see Elwell, C., Hebden, J. (1999) “Near InfraredSpectroscopy” This excellent discussion of NIRS can be found on the internet. It is now possibleto see pictures of vascular brain events as they occur To see the latest imaging development see.Chance et al (1998) “A novel method for fast imaging of brain function, non-invasively, withlight”.
. Jeff and I are now engaged in modifying these events with HEG neurofeedback. I, Hershel
Toomim, illuminate the brain with light and present the colored reflections to the client. Jeff
presents cortical temperatures via infrared energy emitted by metabolically warmed brain blood.
Both techniques are yielding efficient interventions in the alleviation of brain dysfunctions.
Hershel’s Cases
The following study compares outcomes of two 13 year old boys, George and John, initiallysimilar in intelligence and attention as measured by MicroCog, (General Cerebral Functioningand General Cerebral Accuracy) and T.O.V.A (Omissions, Impulsivity, Reaction Time, andVariability).
Figure 2: MicroCog is normalized for 18 years and older. It is used here as a tracking device foryoungsters 10 yr. and up. Scores shown in order: General Cognitive Proficiency, GeneralCognitive Functioning T.O.V.A. Scores in order: Attention, Impulsivity, Reaction Time, Variability Differences:
Note the similarity of the two boys ten session MicroCog scores. MicroCog is a test ofintellectual ability and both boys gained in the 10 sessions. T.O.V.A. scores reveal anotherview. T.O.V.A. is more direct physiological measure than MicroCog. It shows a markeddifference in gain in the Attention score, from <40 to 61 for George and from 98 to 104. forJohn. George was significantly impaired and failed to reach normalcy. John was normal inattention from the beginning.
Careful histories revealed significant facts: George, a “crack baby”, was adopted at age 3 from a drug addicted mother. He is a ten yearmember of his very caring aware adoptive family. His mother felt he had no conscience. He feelsno guilt. She was afraid, before the birth of her new child, that George would harm the newbornchild. Instead, George developed a caring, affectionate relationship with his new sister, Carla,and loves to be assigned for her care. George’s history revealed he had had a severe trauma to thebridge of his nose at age 5 and has been subject to short episodes of feeling “weird” ever since.
His school mates tease him about it. His mother was unaware of this result of the injury. With thehistory of maternal cocaine addiction and suspected seizures a SPECT study and CoherenceQEEG study were ordered John, an engaging youngster with a charming smile, is a juvenile actor earning significant sumstoward his college education. His main difficulties were distractibility and trouble focusing onhis homework. He was recognized as ADD by a neighbor who saw characteristics in John whichwere present in her ADD child. John’s father, also suspected of ADD, is an authoritarian whoexpects perfection in his son. This is a source of continuing stress in the family deflecting thechild’s development .
Neither boy exhibited florid symptoms of hyperactivity although each showed some evidence ofrestless legs during testing. John reached a very high score for the T.O.V.A ADHD whileGeorge had yet to reach a measurable value.
Discussion
The initial MicroCog and T.O.V.A. tests revealed nothing unusual for ADD children in thesetwo youngsters although John’s lower MicroCog scores suggest he would fare less well thanGeorge.
The HEG ability for targeting treatment gives the SPECT study great usefulness. The SPECTlocation of hypoperfused areas mark brain areas with below normal activity which can beactivated with intense neurofeedback exercise.
George’s SPECT study showed significant hypoperfusion in the anterior poles of the temporallobes, hypoperfused foci on the anterior poles of the prefrontal cortex, more severe on the rightthan the left. There is mild hypoperfusion on both cortices above the Sylvian fissure, Werneke’sarea on the left and the visual comparison area on the right. In addition, the right occipital poleshows significant hypoperfusion as does also the right basal ganglia. Significantly, the orbito-frontal cortices, in sagittal section views, show significant hypoperfusion. This area, as shown byAllan N. Schore, is the seat of emotional control and it’s hypoperfusion is likely a residual of theneglected first 3 years of this young man’s life. Kleist (1931, cited in Starkstein, Boston &Robinson 1988) considered the orbito- frontal cortex to be the center of emotional life, and to beimplicated in ethical and moral behaviors. It is noted that there is some evidence of increasedperfusion on the edges of these areas in George’s SPECT study. One can speculate this isevidence of a repair process at work, probably attributable to his 10 years with his present family.
It offers hope that such neglectful injury is not permanent. George, at present is a delightfullyresponsive playful youngster who took to his treatment with appropriate seriousness. There wasno hint of hurt in his recall of his early life.
These considerations guided the selection of HEG treatment areas. Training was for ten minutesat each site, three to four sites per session. For both boys most of the ten session treaning timewas shared among Fp1, Fp2 and Fpz while for George time at F7 and F8 was included and forJohn T5 and T6 were added.
The simplicity of HEG use makes home training practical. George lives in northern Californiawhere there are no known therapists using the HEG technology. His Mother mastered the use ofthe instrumentation in two days and began the study of the brain anatomy involved in George’s injury. She is now using a home HEG trainer to complete George’s therapy. This course oftherapy is expected to require 3 months of three hours weekly.
George’s initial course of therapy at the Biofeedback Institute of Los Angeles was accomplishedin ten consecutive days. This highly intensive exposure is considered to be less than optimallyefficient. There have been no adverse effects noted. Time between sessions is required forvascularity to develop the capacity to supply more oxygenated blood to the exercised corticaltissue. Time for growth between sessions will require fewer sessions.
The treatment plan for George involves continued effort at Fp1, Fpz, Fp2, F7, F8, and Oz untilthe T.O.V.A. normalizes.
George’s brain, so clearly impacted by the bump on the bridge of his nose as shown by thehypoperfused prefrontal areas under Fpz and the contra coup area at Oz, will require upward of40 targeted HEG sessions, far more than the projected 20 sessions for John. Without the targetingcapabilities of HEG there would have been no use for the SPECT study. There would have beenno guidance toward these critical areas.
No treatment is planned for the basal ganglia which is beyond the depth limit of current HEGinstrumentation John’s HEG treatment plan focused on the prefrontal area where the initial T.O.V.A. showedexcess impulsivity errors. These impulsivity errors maximized in half two The target, rare in halfone becomes common in half two of the T.O.V.A. test. John knew each time he made animpulsive error and noted each one with a gasp or body movement. This fact signaled that theinhibitory prefrontal cortex made the proper decision each time but failed to inhibit the buttonpress. The inhibitory neural impulse failed to reach the critical brain area in time to inhibit the, bynow, habitual button press. The frontal cortex was too slow! Further, John’s difficulty in retaining read material could not be traced to working memory sincethe MicroCog working memory sub test was his best score. Careful questioning revealed hisspatial memory was also intact and his difficulty lay in Werneke’s area where translation of theperceived word is translated into understanding.
These considerations led to specifying HEG targeted exercise at Fp1, Fpz, and Fp2 for frontalcortex speed improvement. Eye movement artifact would have precluded this choice if EEGwere the instrument used. T5 was targeted for word translation area exercise while T6maintained brain symmetry.
The validation of these choices is shown by the follow-on testing with T.O.V.A. andMicroCog. After 10 sessions John measured in the normal range for T.O.V.A. Even thoughhe is only 13 years old he scored in the MicroCog normal range for 18 year olds boys. Hismother is happy with his progress in his studies and his teachers report significant improvementin reading. He no longer has to read everything twice.
John is continuing HEG therapy for a projected total of 20 sessions, even though his objectivemeasures are in the normal range. This is mainly because his mother and I have no way to predictthe eventual outcome.
George, on the other hand, still shows deficits in QEEG, SPECT and T.O.V.A.. His motherreports he has been caught stealing and shows no guilt or remorse. His brain injuries clearlysuggest continued training with no clear end as yet in sight.
HEG, in the two cases above illustrates a progression toward more efficient neurofeedbacktherapy made possible by the simplicity and targeting capabilities of the new instrumentation.
HEG enhances the value of SPECT and QEEG coherence studies in shortening and clarifyingobjectives of the neurofeedback process.
Jeff’s Cases
For several years prior to learning about Hershel’s work with HEG, I had been using infraredtechnology to monitor migraine activity. I had also made some unsuccessful attempts at makingthe infrared data work within a feedback paradigm, eventually giving up on the idea. Once Irealized that Hershel had succeeded in using vascular information for feedback, I tried somethings in a different manner than before. Perhaps based as much on serendipity as anything else,the system worked.
My hope was to be able to gain enough control over vascular behavior to directly impactmigraine activity. In monitoring the effects of this system however, I think the mechanism is alittle different. I have been using it in exclusively an Fpz location, picking up data from a circleabout 1.25 inches in diameter. This appears to activate the prefrontal cortex in a manner thatimproves neurovascular regulation. What appears to be happening is that the system responds toincreased frontal perfusion. The perfusion is an effect and possibly also a cause of increasedneural activity, which then improves regulation throughout the brain. It has not been a surprisethat it has produced migraine prophylaxis. It has been a surprise that it can stop a migrainemidstream, because migraine researchers have considered this stage to represent a kind ofvascular paralysis.
I have actively used this system only since 10/1999, so there is no long term data. I have used iton migraine, attentional disturbances, depression and emotional control problems. Migrainestend to respond rapidly and consistently. Attentional problems respond rapidly but sometimesthe effect holds and sometimes not. About 50% of the depression cases have improved rapidlyand held with the other 50% showing no effect at all. I have only limited and variable data onemotional control problems so I am unable to say much at this point.
Although it is very easy to learn to increase the display on the meter, my impression is that unlikeHershel’s 10% criteria, learning and possibly physiological growth occur only after the easyincreases have been achieved and it has started to become difficult to produce further increases.
Time spent in this condition represents “exercise” of the prefrontal cortex. That usually occursafter an increase of about 3 degrees. That is the usual starting point for setting the thresholds tooperate a video. This requires a combination of sustained mental effort with a relaxed affect.
Thresholds are then changed upwards to maintain continued effort. Sessions are 45 to 50minutes in length with 30 to 40 minutes of actual time connected to instruments.
I have selected two cases because they are both interesting and both completed. The firstrepresents a success, the second less so.
This is a 40 year old woman, college graduate, professionally employed, married, referred by herneurologist for medication resistant severe migraine like headaches with aura (scotoma). Theheadaches had increased in frequency over a period of 6 years from occasional to daily. MRI andsleep deprived EEG were normal. There were no correlations with external variables such astime of day, day of week, month, weather. None of the standard prophylactic medications hadhelped. Prednisone stopped one headache but not subsequent ones. Imitrex in various formsreduced pain but did not eliminate the headache. She had a positive family history for migraine.
She also had a tentative diagnosis of Systemic Lupus Erythematosus, which complicated theheadache diagnosis due to the possibility of the pain being generated by vasculitis rather thanmigraine. Raynaud like spasms often preceded headache onset. Mental confusion occurred as anintermittent variable, without warning, lasting several minutes, and leaving without warning.
Fatigue was chronic.
This is not an optimistic scenario. Some of the features present as migraine and some asvasculitis. Based on my experience with Lupus patients, my suspicion was that the headachesrepresented vasculitis, a disorder that is not responsive to biofeedback or neurofeedback. I waswrong.
Headache activity improved after the first HEG session, was gone completely after the fifthsession and has not returned. The patient had a headache during the first and second but notsubsequent sessions. HEG training had no impact on the Raynaud symptoms, nor did subsequentperipheral thermal training. None of the other symptoms changed.
Discussion: This woman has a migraine condition, now probably resolved. She also hasprobable Systemic Lupus Erythematosus that appears to be getting worse. In this case theheadache activity really was migraine activity, probably familial, and probably not directlycaused by the presence of an inflammatory disease process. It is likely that the disease processserved as an aggravating variable possibly influencing the increased frequency of migraines. It islikely that the Raynaud symptoms were inflammatory as they did not respond to peripheraltraining.
This was a highly intelligent 12 year old boy. He was referred by his pediatrician fordysfunctional patterns of attention at home and school with accompanied hyperactivity, meetingDSM IV criteria for 314.01 (Attention-Deficit/Hyperactivity Disorder, PredominantlyHyperactive-Impulsive Type. These patterns had existed since birth. No prenatal factors wereidentified, but a strong family history for similar behaviors was present. Unlike many childrendiagnosed with ADHD, he had a pleasant disposition, and presented no behavior problems.
School performance was erratic through elementary years, but had deteriorated to a level ofconsistent borderline failing by middle school. His WISC III scores were in the 95th percentilerange.
He could not sit still at home or school. Squirms per minute while trying to sit still averaged 60per minute. Typical sustained attention by self report and also as measured with skinconductance responses was 5 to 10 seconds, while trying to maintain attention. He was easilydistracted under all conditions and all locations, including home, school and my office. Theshort attention span and easy distractibility maintained even when engaged in activities that forhim held high interest. He had an excellent response to Ritalin, but due to a coexisting migrainecondition could not continue with it as it produced a rebound migraine at the end of the day.
Even when not taking Ritalin, severe migraines would occur 1 or 2 times per week, accompaniedby photophobia. The headaches were not a target of treatment.
Treatment combined a primary emphasis on HEG at Fpz for increased focus, along with asecondary emphasis on skin conductance for general arousal reduction training. He was a willingand active participant in the process. Improvements were noted in the first session, with allmeasures normalizing. Squirms per minute reduced to an average of 1. Measured and reportedshifts of attention were only occasional with sustained attention typically exceeding 60 seconds.
Skin conductance levels reduced from an average of 16 to 5 micromho’s, with increased stability.
His skin became less sensitive and less ticklish. I saw him at 8:00 in the morning for the firstsession. He had an abnormally excellent day at school.
I worked with this young man for 8 months, incorporating 20 sessions, primarily HEG with someskin conductance. Two response curves developed.
The first relates to his attentional patterns. Normalization occurred gradually over a period of 3months. At the end of that period, his behavior was as well managed as when he was on Ritalin.
Then it slowly reversed itself. By the end of 8 months, his behavior had essentially returned tobaseline. It still normalized as soon as he was connected to an instrument, but deteriorated againas soon as he was “free” of the instrument.
The second relates to his headache activity. By the end of the initial 3 months he noticed that hewas no longer getting migraines. This was a non-targeted symptom. The migraines have notreturned.
Discussion: It is very difficult to say what happened here. The normalization of a neurologicalcondition such as migraine suggests that there has been some neurological reorganization. Theinitial improvements in his ADHD related behaviors also suggests that, but the subsequent deterioration is a curiosity. One hint as to the source of the problem comes from the young manhimself. He stated that he likes himself much better when he is “hyper”. He doesn’t like thefeeling that comes with being “steady”. It seems that we may have ultimately entered the realmof personal choice.
Summary:
We have reported two sets of case studies using two different HEG systems. For the sake ofperspective, each of us has chosen to report one case in which HEG was very effective, and onecase in which it was less than optimally effective. The typical response to both systems has beena relatively rapid improvement in symptoms that often take longer to resolve with EEG andperipheral based formats. We have both found that HEG’s freedom from eye movement artifactsand EMG artifacts makes working with the frontal regions of the brain easy rather thanfrustrating. Also, because of that freedom from artifact, it may be producing data for feedbackthat is more reliable and valid than EEG based systems.
References
Chance, B., Anday, E., Nioka, S., Zhou, S., Hong, H., Worden, K., Li, C., Murray, T., Ovetsky, Y., Pigilikity, D., Thomas, R. (1998) A novel method for fast imaging ofbrain function, non-invasively, with light. Optics Express. 10 (pp 411-423) Chance, B., Zhung, Z., Chu, U., Alter, C., Lipton, L. Cognition activated low frequency modulation of light absorption in human brain. (1993) Proc. Natl. Acad. Sci USA. 90, (pp 2660-2774)Elwell, C., Hebden, J. Near Infrared Spectroscopy. Biomedical Optics Research Group http//www.medphys.ucl.ac.ik/research/borg/research/NIR-topics/nrs.htm.
Jobsis, FF. Monitor of metabolic changes with near infra red light transmittance, (1977) Roland, Per E. (1993) Brain Activation. New York, Wiley-Liss (pp 469-504) References
Chance, B., Anday, E., Nioka, S., Zhou, S., Hong, H., Worden, K., Li, C., Murray, T., Ovetsky, Y., Pigilikity, D., Thomas, R. (1998) A novel method for fast imaging ofbrain function, non-invasively, with light. Optics Express. 10 (pp 411-423) Chance, B., Zhung, Z., Chu, U., Alter, C., Lipton, L. Cognition activated low frequency modulation of light absorption in human brain. (1993) Proc. Natl. Acad. Sci USA. 90, (pp 2660-2774)Elwell, C., Hebden, J. Near Infrared Spectroscopy. Biomedical Optics Research Group http//www.medphys.ucl.ac.ik/research/borg/research/NIR-topics/nrs.htm.
Jobsis, FF. Monitor of metabolic changes with near infra red light transmittance, (1977) Kleist (1931), cited in Starkstein ,S.E., Boston, J.D., & Robinson, R.F., (1988).
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Roland, Per E. (1993) Brain Activation. New York, Wiley-Liss (pp 469-504)

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