Too many hits? It is an old sports term, used to describe the running back who suddenly went from a Hall of Fame credentials, to ordinary, to out of football. It seems like half of the greatest running backs of all time went thru it.
If you are old enough to remember Earl Campbell, you would argue that no modern running back could carry his helmet. Yet, he went from absolutely amazing to positively mediocre, almost overnight. In 1983, he gained 1301 yards. In 1984, he had only 468. Even playing for his beloved coach Bum Phillips in New Orleans in 1985, he could only muster 643 yards, and then he was gone. http://www.profootballhof.com/hof/member.jsp?player_id=40
The younger readers may have only heard of Earl because of his relationship to the scandal of the way the NFL treats its veterans and their medical needs. http://www.cyclonefanatic.com/forum/pro-sports/18098-earl-campell-texas-legend.html
Others have their explanations for his disability. Mine: It all starts in the brain. We know that boxers ultimately become demented because of too many hits, but think of the force that a running back absorbs on nearly every carry. Is it a surprise that the cumulative impact of that force on the microscopic connective wires within the brain – the axons, ultimately effects thought, the nervous system and the way in which the brain and nervous system control the body?
There are three incomparable running backs in my adult years: Earl Campbell, Walter Payton and Emmitt Smith. Payton is the exception, I have no head injury theories with respect to him. But I remember the Cowboy Emmitt Smith in a way that only a Packer fan can. He just found a way to beat you. Not the fastest, not the biggest, not perhaps even the most elusive. He just had a knack. Big difference between Emmitt and Earl was that while Emmitt could run over people, he preferred to make them miss. Earl just ran over you for the sport of it. Well, Emmitt didn’t have that sudden career collapse that Earl did. He played successfully his last years in the game although the Cowboys did give up on him.
In my theories, the big change in Emmitt wasn’t because of the cumulative total of a lot of hits. His change seemed to occur all at once. On a Monday night game, against the Bears, Emmitt jumped over a pile and landed straight on his head. The way I remember it, it was a touchdown. It was the neck injury that got everyone excited. But I don’t believe Emmitt ever had quite the same knack after that play. His Cowboys never knocked the Packers out of the Playoffs again.
Why is Subtle Brain Injury© so disabling to a running back? A Subtle Brain Injury first effects the processing speed potentials of the brain because it disrupts white matter, the axons. While men in general are not as white matter dependent as women (a topic for another blog) athletes, especially those who must have instantaneous responses, are.
Assume that a running back needs 2 billion axons (to pick an entirely artificial number) to be able to react quickly enough to all of the different stimuli, applied memory and decision making of carrying the football. This pre-injury capacity gives the great runner the ability to know to cut left instead of right, situationally depending on whether it is All Pro Jimmy Linebacker who is trying to crush him versus Johnny Lineman. For more on diffuse axonal injury, click here.
Well, let’s also assume that our hypothetical running back started his career with 2.5 billion axons, but every hit robs him of a few and all of the blindsided ones, millions. Well when suddenly his reserves drop below 2 billion, he can’t react quickly enough to avoid the All Pros, but can still make the average defensive player miss. But now when Mr. All Pro hits him hundreds of millions of axons are lost, and it only takes a few more games until he can’t avoid even Mr. Average anymore. His strength is the same, his speed is the same, but his instincts are gone. Pretty soon the speed will go too because of the cumulative total of all those hits on his muscles and joints.
Well, this week’s news has another story of a legendary running back who went from All World, to worst trade in history in a short span, Herschel Walker. Walker went from 1514 yards in 1988 to 915 yards in 1989. While there are those who will say that this had to do with the way in which he was used after he left the Cowboys for Minnesota, true football fans will know that he just never had the same special quality after leaving the Cowboys. Like Earl Campbell, Walker used his amazing strength and power to punish defenders.
Now, Herschel Walker is newsworthy because of mental illness. See http://www.philly.com/philly/sports/eagles/20080415_NFL___Herschel_Walker_talks_of_mental_illness.html OK, that is possibly the explanation, but I am not convinced. Too many hits equals too much brain damage, which adds up to potential for serious neurobehavioral disorders.
If you think I am seeing brain injury under every rock, perhaps I am. But would someone please explain to me why the Poster Child for brain injury in sport – Mike Tyson, was never disqualified from boxing because of brain injury? If his complete inability to not bite Evander Holyfield’s ears is not a symptom of brain injury, then the world is flat. (For someone who shares my belief about Mike Tyson and brain injury, click here.)
I am not an expert in football or boxing although my first career was as a sport writer. I am not a medical doctor, so technically I am not an expert in brain injury either. But I do know both sports and brain injury and I know enough to recognize the patterns that point to brain damage. Is there enough force, is there evidence of injury and is there a change in the person? Emmitt I am suspicious about, especially the short term effect of the season he landed on his head. Of Earl, Herschel and Mike Tyson, I have no doubt.
TBI Act Reauthorization
From the Brain Injury Association of Wisconsin
But how come the tail of the brain injury animal, war injuries, gets all of the research and attention? There are a million Subtle Brain Injuries© a year in the U.S. and perhaps, a few thousand in Iraq. What about all the civilians who have brain injuries? Isn’t it time we did some major research on those most likely to be disabled by brain injuries, those over 40 – especially women over 40, those with prior head injuries and those with co-morbid issues such as other neurologic or emotional disorders?
A Subtle Brain Injury is a complicated synergistic maze. Limiting our research to young jocks and war casualties is not going to enlighten us as to why some people have apparent full recoveries and others never get better. It is not an accident that there is consistently 10-15% of those with concussions who wind up with persistant post concussion syndrome. Let us start screaming louder so that the real pathology in those cases is understood, and treated.
- TBI Act Reauthorization Update: Last week the US Congress passed legislation to reauthorize the Traumatic Brain Injury Act! The bill appears ready to be sent on to President Bush for his signature. In addition to authorizing ongoing CDC, NIH and HRSA TBI programs, the bill also authorizes a new study by the CDC and NIH in collaboration with the Dept. of Defense and the Dept. of Veterans Affairs to identify the incidence of brain injury among our veterans, especially veterans of Iraq and Afghanistan. Again, THANK YOU to all who took time to share their opinions with Congress regarding this legislation during the past year.
But how come the tail of the brain injury animal, war injuries, gets all of the research and attention? There are a million Subtle Brain Injuries© a year in the U.S. and perhaps, a few thousand in Iraq. What about all the civilians who have brain injuries? Isn’t it time we did some major research on those most likely to be disabled by brain injuries, those over 40 – especially women over 40, those with prior head injuries and those with co-morbid issues such as other neurologic or emotional disorders?
A Subtle Brain Injury is a complicated synergistic maze. Limiting our research to young jocks and war casualties is not going to enlighten us as to why some people have apparent full recoveries and others never get better. It is not an accident that there is consistently 10-15% of those with concussions who wind up with persistant post concussion syndrome. Let us start screaming louder so that the real pathology in those cases is understood, and treated.
Another Brain Injury Goodbye
Yesterday I dedicated this blog to the death of a great pioneer in the field of brain injury, Bryan Jennett, M.D. of the GCS scale. Today, I would like to give best wishes to a former advocacy colleague of mine, Pat David, of the Brain Injury Association of Wisconsin. I joined this organization in 1994 and became a member of its board for several years thereafter. Pat was the rock of that organization since that time and today announced her retirement. It comes with some good news, the passing in the House of Representatives of the TBI Act.
Here is the BIAW’s press release relative to Pat:
Dear Members & Donors:
I wanted to inform you of my pending retirement from the Brain Injury Association in June of 2008. I am so grateful for the past fifteen years and the opportunity to serve individuals with brain injury and their families in Wisconsin. I want to thank you, our members and donors, because it is your support that is the foundation upon which this organization was built and will grow. It has been a true privilege for which I am grateful.
Our Board of Directors is currently in the process of screening applicants for the Executive Director position and establishing a process for interviewing. We are also receiving input from our collaborative partners from the Dept. of Health and Family Services and the WI Brain Injury Advisory Council. Our plan is to have an individual in place before my departure to facilitate a smooth transition. I will keep you informed as that process further evolves.
I also need to share some breaking news….Yesterday, the US House of Representatives passed legislation to reauthorize the TBI Act (S. 793), by a vote of 392-1. The bill authorizes programs over the period of FY 2009 through FY 2012. Thanks to all who made their opinions known by contacting their Representative! The bill will next go to the US Senate once again, where approval is expected. Pending passage in the Senate, it would then be sent on to the President for his signature.
Thank you and do not hesitate to contact us at admin@biaw.org or 1-800-882-9282 with questions.
Sincerely yours,
Pat David
Director of Operations
Pat, your absence will be felt and I trust that your successor will do his or her best to carry on your mission.
Here is the BIAW’s press release relative to Pat:
Dear Members & Donors:
I wanted to inform you of my pending retirement from the Brain Injury Association in June of 2008. I am so grateful for the past fifteen years and the opportunity to serve individuals with brain injury and their families in Wisconsin. I want to thank you, our members and donors, because it is your support that is the foundation upon which this organization was built and will grow. It has been a true privilege for which I am grateful.
Our Board of Directors is currently in the process of screening applicants for the Executive Director position and establishing a process for interviewing. We are also receiving input from our collaborative partners from the Dept. of Health and Family Services and the WI Brain Injury Advisory Council. Our plan is to have an individual in place before my departure to facilitate a smooth transition. I will keep you informed as that process further evolves.
I also need to share some breaking news….Yesterday, the US House of Representatives passed legislation to reauthorize the TBI Act (S. 793), by a vote of 392-1. The bill authorizes programs over the period of FY 2009 through FY 2012. Thanks to all who made their opinions known by contacting their Representative! The bill will next go to the US Senate once again, where approval is expected. Pending passage in the Senate, it would then be sent on to the President for his signature.
Thank you and do not hesitate to contact us at admin@biaw.org or 1-800-882-9282 with questions.
Sincerely yours,
Pat David
Director of Operations
Pat, your absence will be felt and I trust that your successor will do his or her best to carry on your mission.
In Memoriam Bryant Jennett – Glasgow Coma Scale Author
In general, brain injury research and work is a pretty anonymous field. I can rattle off a bunch of names of researchers, but even most defense experts have never heard of many of these people. One of the names that almost everyone in the brain injury field has heard is Bryan Jennett. If they haven’t heard of him, they have heard of his most famous work: the Glasgow Coma Scale, commonly referred to as the GCS. The GCS score is the most single common denominator in all of head injury diagnosis, and any cursory review of a brain injury medical record will have a GCS score on it.
Bryan Jennett, CBE, M.D., the brain injury expert of Glasgow, Scotland, died on 16 February 2008. For a nice treatment on Dr. Jennett click here. The North East Center also includes a nice comment on his work on such link by Nathan Zasler, M.D. that is worth reading – Reflections on the Life and Work of William Bryan Jennett, CBE, M.D., FRCS. Dr. Zasler had this to say about Dr. Jennett:
“During his career, Dr. Jennett not only distinguished himself as a clinician and scholar but lectured and wrote extensively on issues relating to brain injury.
“He remained one of the driving forces behind some of the more recent international work in the area of disorders of consciousness over the last 15 years. What was most amazing was Dr. Jennett’s ability to look back on his own work and be constructively critical of it, including acknowledging some of the limitations of his own thinking. He continued to provide encouragement to other clinicians to pursue further honing of our collective understanding of the complexities of both assessment and management of this special population of persons with acquired brain injury.”
Only if this generation of doctors, scholars and researchers can share Dr. Jennett’s passion and vision for the future of brain injury research, will the advocacy that propelled Dr. Jennett’s career, be fulfilled. I hope his death reminds the medical community of that what we don’t know about brain injury is infinitely greater than what we know. Research on…
Next: the GCS score. What it tells us and what it does not.
Bryan Jennett, CBE, M.D., the brain injury expert of Glasgow, Scotland, died on 16 February 2008. For a nice treatment on Dr. Jennett click here. The North East Center also includes a nice comment on his work on such link by Nathan Zasler, M.D. that is worth reading – Reflections on the Life and Work of William Bryan Jennett, CBE, M.D., FRCS. Dr. Zasler had this to say about Dr. Jennett:
“During his career, Dr. Jennett not only distinguished himself as a clinician and scholar but lectured and wrote extensively on issues relating to brain injury.
“He remained one of the driving forces behind some of the more recent international work in the area of disorders of consciousness over the last 15 years. What was most amazing was Dr. Jennett’s ability to look back on his own work and be constructively critical of it, including acknowledging some of the limitations of his own thinking. He continued to provide encouragement to other clinicians to pursue further honing of our collective understanding of the complexities of both assessment and management of this special population of persons with acquired brain injury.”
Only if this generation of doctors, scholars and researchers can share Dr. Jennett’s passion and vision for the future of brain injury research, will the advocacy that propelled Dr. Jennett’s career, be fulfilled. I hope his death reminds the medical community of that what we don’t know about brain injury is infinitely greater than what we know. Research on…
Next: the GCS score. What it tells us and what it does not.
EDITORS NOTE: From the Brain Injury Association of America:
Attorney Gordon Johnson
http://subtlebraininjury.com
http://tbilaw.com
https://waiting.com
http://vestibulardisorder.com
http://youtube.com/profile?user=braininjuryattorney
g@gordonjohnson.com
800-992-9447
Brain Injury Association of America
Policy Corner E-Newsletter – April 4, 2008
A weekly update on federal policy activity related to traumatic brain injury
__________________________________________________________________
Dear Advocates:
This week BIAA submitted written testimony to the House Appropriations Subcommittee in charge of funding TBI programs within the Department of Health and Human Services and the Department of Education, urging an increase in Fiscal Year 2009 funding for TBI programs.
On Wednesday, April 2, the House Veterans Affairs Subcommittee on Oversight and Investigations held a hearing on TBI Related Vision Issues, which highlighted the high rate of vision disturbances in cases of servicemembers returing from Iraq and Afghanistan with TBI.
Also this week, the House Energy and Commerce Committee held a hearing on H.R. 5613, legislation recently introduced which would place a moratorium until March 2009 on seven Medicaid regulations issued by the Department of Health and Human Services. BIAA has endorsed this legislation, and signed a letter of support spearheaded by the Consortium of Citizens with Disabilities (CCD) in favor of the legislation.
Unfortunately, no activity occurred this week on H.R. 1418, the House version of legislation to reauthorize the TBI Act, which was passed by the House Energy and Commerce Act on March 13, 2008. BIAA will continue to advocate strongly for floor consideration of the bill by the entire House of Representatives and full passage by Congress into law as quickly as possible.
*Distributed by Laura Schiebelhut, BIAA Public Affairs Manager, on behalf of the Brain Injury Association of America; 703-761-0750 ext. 637; lschiebelhut@biausa.org
The Policy Corner is made possible by the Adam Williams Initiative, Centre for Neuro Skills, and Lakeview Healthcare Systems, Inc. The Brain Injury Association of America gratefully acknowledges their support for legislative action.
__________________________________________________________________
BIAA Submits Testimony to House Labor-HHS-Education Appropriations Subcommittee
This week BIAA submitted written testimony to the House Appropriations Subcommittee in charge of funding TBI programs within the Department of Health and Human Services and the Department of Education. BIAA’s testimony urges an increase in Fiscal Year 2009 funding for programs authorized through the TBI Act, as well as for TBI research programs conducted within the National Institute on Disability and Rehabilitation Research (NIDRR).
In the testimony, BIAA’s President and CEO Susan H. Connors states, “BIAA was gravely disappointed that last year, even as Congress had the good judgment to add hundreds of millions dollars to the budgets of the Department of Defense and the Department of Veterans Affairs to help address the problem of TBI among returning servicemembers, funding for the HRSA Federal TBI Program was reduced from $8.91 million to $8.754 million.”
Within the testimony, BIAA requests $30 million in funding for programs authorized through the TBI Act, as well as sufficient funding to sustain and increase medical rehabilitation research within NIDRR. The testimony also urges an allocation of at least $8.3 million to allow NIDRR to continue to fund 16 TBI Model Systems research centers.A copy of the testimony can be obtained by visiting BIAA’s website at the following address: http://www.biausa.org/policyissues.htm.
House VA Subcommittee Holds Hearing on TBI And Vision Problems
On Wednesday, April 2, the House Veterans Affairs Subcommittee on Oversight and Investigations held a hearing on TBI Related Vision Issues.
Testimony highlighted the high rate of vision disturbances in cases of servicemembers returing from Iraq and Afghanistan with TBI, and the need for a seamless system of care within the Department of Defense and Department of Veterans Affairs to address these eye injuries, including greater use of specialized vision screening.
In the hearing, the Blinded Veterans Association (BVA) noted research showing that 75 percent of servicemembers with documented TBI injuries also have complaints about vision problems, and that approximately 60 percent of those injured have associated neurological visual disorders. A study conducted by one of the panelists, Gregory L. Goodrich, who is a research psychologist at the VA Palo Alto Health Care System, found that both Polytrauma Level I and Level II patients had high rates of visual impairment and/or visual dysfunction, and that injuries caused by a blast event were associated with more vision related loss and/or deficits than other causes.
In his testimony, Tom Zampieri, Director of Government Relations at BVA, asserted, “At present the current system of screening, treatment, tracking, and follow-up care for TBI vision dysfunction is inadequate. Adding visual dysfunction to this complex mix, especially if undiagnosed, makes attempts at rehabilitation even more daunting and potentially disastrous unless there are significant improvements soon.”
Mr. Zampieri urged the Subcommittee to request that DoD/VA provide for the full implementation of the “Military Eye Trauma Center of Excellence and Eye Trauma Registry,” which was recently authorized as one of the Wounded Warrior provisions in last year’s defense authorization bill (H.R. 4986). BIAA has officially endorsed legislation (S. 1999) to create such a Center.
BIAA Supports Bill to Enact Moratorium on Harmful Medicaid Regulations
Also this week, the House Energy and Commerce Committee held a hearing on H.R. 5613, legislation recently introduced which would place a moratorium until March 2009 on seven Medicaid regulations issued by the Department of Health and Human Services. BIAA has endorsed this legislation, and signed a letter of support spearheaded by the Consortium of Citizens with Disabilities (CCD) in favor of the legislation.
The legislation, which was introduced by Representatives John D. Dingell (D-MI) and Tim Murphy (R-PA) on March 13, 2008, would delay the implementation of seven harmful Medicaid regulations through March 2009, including several rules which would be especially deleterious to individuals with traumatic brain injury.
One of these rules would limit rehabilitation services for Medicaid beneficiaries, severely curtailing the ability of people with disabilities – including TBI – to receive rehabilitation services now covered under Medicaid. Access to these rehabilitative services is essential, as in many cases, these services play a vital role in allowing people with TBI to live independently in the community.
Attorney Gordon Johnson
http://subtlebraininjury.com
http://tbilaw.com
https://waiting.com
http://vestibulardisorder.com
http://youtube.com/profile?user=braininjuryattorney
g@gordonjohnson.com
800-992-9447
Brain Injury Association of America
Policy Corner E-Newsletter – April 4, 2008
A weekly update on federal policy activity related to traumatic brain injury
__________________________________________________________________
Dear Advocates:
This week BIAA submitted written testimony to the House Appropriations Subcommittee in charge of funding TBI programs within the Department of Health and Human Services and the Department of Education, urging an increase in Fiscal Year 2009 funding for TBI programs.
On Wednesday, April 2, the House Veterans Affairs Subcommittee on Oversight and Investigations held a hearing on TBI Related Vision Issues, which highlighted the high rate of vision disturbances in cases of servicemembers returing from Iraq and Afghanistan with TBI.
Also this week, the House Energy and Commerce Committee held a hearing on H.R. 5613, legislation recently introduced which would place a moratorium until March 2009 on seven Medicaid regulations issued by the Department of Health and Human Services. BIAA has endorsed this legislation, and signed a letter of support spearheaded by the Consortium of Citizens with Disabilities (CCD) in favor of the legislation.
Unfortunately, no activity occurred this week on H.R. 1418, the House version of legislation to reauthorize the TBI Act, which was passed by the House Energy and Commerce Act on March 13, 2008. BIAA will continue to advocate strongly for floor consideration of the bill by the entire House of Representatives and full passage by Congress into law as quickly as possible.
*Distributed by Laura Schiebelhut, BIAA Public Affairs Manager, on behalf of the Brain Injury Association of America; 703-761-0750 ext. 637; lschiebelhut@biausa.org
The Policy Corner is made possible by the Adam Williams Initiative, Centre for Neuro Skills, and Lakeview Healthcare Systems, Inc. The Brain Injury Association of America gratefully acknowledges their support for legislative action.
__________________________________________________________________
BIAA Submits Testimony to House Labor-HHS-Education Appropriations Subcommittee
This week BIAA submitted written testimony to the House Appropriations Subcommittee in charge of funding TBI programs within the Department of Health and Human Services and the Department of Education. BIAA’s testimony urges an increase in Fiscal Year 2009 funding for programs authorized through the TBI Act, as well as for TBI research programs conducted within the National Institute on Disability and Rehabilitation Research (NIDRR).
In the testimony, BIAA’s President and CEO Susan H. Connors states, “BIAA was gravely disappointed that last year, even as Congress had the good judgment to add hundreds of millions dollars to the budgets of the Department of Defense and the Department of Veterans Affairs to help address the problem of TBI among returning servicemembers, funding for the HRSA Federal TBI Program was reduced from $8.91 million to $8.754 million.”
Within the testimony, BIAA requests $30 million in funding for programs authorized through the TBI Act, as well as sufficient funding to sustain and increase medical rehabilitation research within NIDRR. The testimony also urges an allocation of at least $8.3 million to allow NIDRR to continue to fund 16 TBI Model Systems research centers.A copy of the testimony can be obtained by visiting BIAA’s website at the following address: http://www.biausa.org/policyissues.htm.
House VA Subcommittee Holds Hearing on TBI And Vision Problems
On Wednesday, April 2, the House Veterans Affairs Subcommittee on Oversight and Investigations held a hearing on TBI Related Vision Issues.
Testimony highlighted the high rate of vision disturbances in cases of servicemembers returing from Iraq and Afghanistan with TBI, and the need for a seamless system of care within the Department of Defense and Department of Veterans Affairs to address these eye injuries, including greater use of specialized vision screening.
In the hearing, the Blinded Veterans Association (BVA) noted research showing that 75 percent of servicemembers with documented TBI injuries also have complaints about vision problems, and that approximately 60 percent of those injured have associated neurological visual disorders. A study conducted by one of the panelists, Gregory L. Goodrich, who is a research psychologist at the VA Palo Alto Health Care System, found that both Polytrauma Level I and Level II patients had high rates of visual impairment and/or visual dysfunction, and that injuries caused by a blast event were associated with more vision related loss and/or deficits than other causes.
In his testimony, Tom Zampieri, Director of Government Relations at BVA, asserted, “At present the current system of screening, treatment, tracking, and follow-up care for TBI vision dysfunction is inadequate. Adding visual dysfunction to this complex mix, especially if undiagnosed, makes attempts at rehabilitation even more daunting and potentially disastrous unless there are significant improvements soon.”
Mr. Zampieri urged the Subcommittee to request that DoD/VA provide for the full implementation of the “Military Eye Trauma Center of Excellence and Eye Trauma Registry,” which was recently authorized as one of the Wounded Warrior provisions in last year’s defense authorization bill (H.R. 4986). BIAA has officially endorsed legislation (S. 1999) to create such a Center.
BIAA Supports Bill to Enact Moratorium on Harmful Medicaid Regulations
Also this week, the House Energy and Commerce Committee held a hearing on H.R. 5613, legislation recently introduced which would place a moratorium until March 2009 on seven Medicaid regulations issued by the Department of Health and Human Services. BIAA has endorsed this legislation, and signed a letter of support spearheaded by the Consortium of Citizens with Disabilities (CCD) in favor of the legislation.
The legislation, which was introduced by Representatives John D. Dingell (D-MI) and Tim Murphy (R-PA) on March 13, 2008, would delay the implementation of seven harmful Medicaid regulations through March 2009, including several rules which would be especially deleterious to individuals with traumatic brain injury.
One of these rules would limit rehabilitation services for Medicaid beneficiaries, severely curtailing the ability of people with disabilities – including TBI – to receive rehabilitation services now covered under Medicaid. Access to these rehabilitative services is essential, as in many cases, these services play a vital role in allowing people with TBI to live independently in the community.
Consistent Best Effort
This week I have been discussing the basic principles of neuropsychological assessment, and its two foundational assumptions: the ability to reconstruct pre-morbid IQ and the need for “consistent best effort”. Yesterday’s blog dealt with the pre-morbid IQ. Today, we will discuss the issue of “consistent best effort.”
The number side of the neuropsychological assessment is based upon the theory that a neuropsychologist can make certain conclussions about pathology based upon an examination of the pattern of test scores. The process of doing this is called “discrepancy analysis”, meaning that if there is a discrepancy in certain areas, this points to pathology. Two other terms are important: “relative weakness” and “intraindividual comparison”. If while doing the intraindividual comparision (mean comparing the patient, only to his or her own scores versus the population as a whole) a “relative weakness” shows up, then that means something.
In a perfect world, it is a beautiful theory. You chart the scores, the “relative weakness” jumps out at the neuropsychologist, you look to the part of the brain that controls that area of function, and thus, make a diagnosis. The fundamental problem is that you must be able to presume that the test subject was making the same effort during the test where he or she did poorly, as across the entire battery of tests. But can we make that assumption?
I like to quote from depositions I have done to make these type of points, and I will do that again. My apologies to my son for my references to his middle school running career.
12 Q (By Mr. Johnson) Do you still have your Exhibit Number 1
13 before you?
14 A I do.
15 Q Page 6?
16 A Yes.
17 Q Now, as I understand what you’re saying in the first
18 paragraph of Page 6, what you’re saying is that because you
19 cannot be sure that the patient did not give optimum effort,
20 that you can’t reach conclusions based on the data in those
21 testing — in that testing; is that correct?
22 A I can make certain conclusions, but not on her current
23 status, on that date. That’s what I’m — all I’m trying to say
24 is this set of data had serious reservations because of lack of
25 effort.
54
1 Q Now, there are any number of things — strike that. Let’s
2 talk about the continuum of effort when you’re giving someone a
3 test; all right? I’ll give you an example.
4 My son, who is a 13 year old, goes out and runs a six-
5 minute mile, and he gave better effort than anyone else in the
6 class if you judge it just based on his performance, because he
7 won the race; okay?
8 A Got you.
9 Q Now, would that be considered best effort?
10 A It was certainly a sufficient effort to be recorded, yes.
11 Q Two months later in a track meet in his conference meet,
12 he’s able to run a five-minute, six-second mile without
13 significant change in this training status. In comparison to
14 the gym class — in comparison to the conference meet time of
15 five minutes and six seconds, did he give best effort in gym
16 class?
17 A There are other variables that have to be considered, and
18 I’d have to know other things. I’m not really following you.
19 Q Okay. Tell me what the variables would be.
20 A Like the environmental conditions, the contingencies if he
21 won or if he didn’t win, the particular mood or attitude that he
22 had on that day, how his physical health was, if he had a cold,
23 if he had some sort of limitation.
24 Q Now, we always have all of those limitations anytime we
25 give someone any type of test; is that correct?
55
1 A Exactly right.
2 Q If we were going to pick an example of when we might get
3 the highest percentage of people giving maximal effort or
4 optimal effort, is there a better example than the law school
5 admission test?
6 A Well, I’ve never seen the law school admission test, but if
7 it’s like the test that I took to get to graduate school, then
8 one certainly has to do well, as best as they can, yes.
9 Q And can we — if there ever — can we ever presume a higher
10 likelihood of maximum effort in an academic test than we would
11 in something like a law school or a medical college admissions?
12 A Well, I agree. I mean, one can’t do better than one can
13 do.
14 Q But what’s unique about the law school and the medical
15 school admission test, is people’s whole lives revolve around
16 how they do on this test; correct?
17 A Well, that’s probably their interpretation, but it’s not
18 real. They probably think —
19 Q And that thinking that would convince them at least
20 relative to other variables to give it their best shot?
21 A I would think so, yes.
22 Q Despite that, sometimes people who are testing in high-
23 pressure situations like a law school admissions test or a
24 medical college entrance exam, do not wind up at their optimum
25 performance level; correct?
56
1 A I presume that’s correct.
2 Q And what explanations for that would do?
3 A Again, we just went through some of them. They have a
4 cold, they’re worried about money, they have stress at home,
5 they have stress on the job, I mean, there are all kinds of
6 events that could influence particular effort on a particular
7 day.
8 Q Or actually the stress of the test itself?
9 A Well, yes, of course. There’s some people who don’t do
10 well on tests.
11 Q And there are some people who do worse the more the
12 pressure is?
13 A Right. It’s not really the pressure; it’s how the patient
14 manages the pressure that’s the issue.
Now as we consider this long introduction in the context of the search for “relative weaknesses”, what does that mean? What if our test subject was only using the gym class effort level, versus the conference meet effort level? Can we make statistical comparisons then? Or should we compare that performance to how people do in gym class, and not comparing how they do in more stimulating environments?
Neuropsychology is a science, right? They should have control out all of these variables, right? Guess again, not because they don’t want to, but because they are dealing with human beings, and in brain injury evaluations, human beings who prevented from doing what they are presumed to do, based upon the precise disability for which we are evaluating them: brain damage.
Next: The Scope of the Problem for Brain Injured Person in Giving Consistent Best Effort.
The number side of the neuropsychological assessment is based upon the theory that a neuropsychologist can make certain conclussions about pathology based upon an examination of the pattern of test scores. The process of doing this is called “discrepancy analysis”, meaning that if there is a discrepancy in certain areas, this points to pathology. Two other terms are important: “relative weakness” and “intraindividual comparison”. If while doing the intraindividual comparision (mean comparing the patient, only to his or her own scores versus the population as a whole) a “relative weakness” shows up, then that means something.
In a perfect world, it is a beautiful theory. You chart the scores, the “relative weakness” jumps out at the neuropsychologist, you look to the part of the brain that controls that area of function, and thus, make a diagnosis. The fundamental problem is that you must be able to presume that the test subject was making the same effort during the test where he or she did poorly, as across the entire battery of tests. But can we make that assumption?
I like to quote from depositions I have done to make these type of points, and I will do that again. My apologies to my son for my references to his middle school running career.
12 Q (By Mr. Johnson) Do you still have your Exhibit Number 1
13 before you?
14 A I do.
15 Q Page 6?
16 A Yes.
17 Q Now, as I understand what you’re saying in the first
18 paragraph of Page 6, what you’re saying is that because you
19 cannot be sure that the patient did not give optimum effort,
20 that you can’t reach conclusions based on the data in those
21 testing — in that testing; is that correct?
22 A I can make certain conclusions, but not on her current
23 status, on that date. That’s what I’m — all I’m trying to say
24 is this set of data had serious reservations because of lack of
25 effort.
54
1 Q Now, there are any number of things — strike that. Let’s
2 talk about the continuum of effort when you’re giving someone a
3 test; all right? I’ll give you an example.
4 My son, who is a 13 year old, goes out and runs a six-
5 minute mile, and he gave better effort than anyone else in the
6 class if you judge it just based on his performance, because he
7 won the race; okay?
8 A Got you.
9 Q Now, would that be considered best effort?
10 A It was certainly a sufficient effort to be recorded, yes.
11 Q Two months later in a track meet in his conference meet,
12 he’s able to run a five-minute, six-second mile without
13 significant change in this training status. In comparison to
14 the gym class — in comparison to the conference meet time of
15 five minutes and six seconds, did he give best effort in gym
16 class?
17 A There are other variables that have to be considered, and
18 I’d have to know other things. I’m not really following you.
19 Q Okay. Tell me what the variables would be.
20 A Like the environmental conditions, the contingencies if he
21 won or if he didn’t win, the particular mood or attitude that he
22 had on that day, how his physical health was, if he had a cold,
23 if he had some sort of limitation.
24 Q Now, we always have all of those limitations anytime we
25 give someone any type of test; is that correct?
55
1 A Exactly right.
2 Q If we were going to pick an example of when we might get
3 the highest percentage of people giving maximal effort or
4 optimal effort, is there a better example than the law school
5 admission test?
6 A Well, I’ve never seen the law school admission test, but if
7 it’s like the test that I took to get to graduate school, then
8 one certainly has to do well, as best as they can, yes.
9 Q And can we — if there ever — can we ever presume a higher
10 likelihood of maximum effort in an academic test than we would
11 in something like a law school or a medical college admissions?
12 A Well, I agree. I mean, one can’t do better than one can
13 do.
14 Q But what’s unique about the law school and the medical
15 school admission test, is people’s whole lives revolve around
16 how they do on this test; correct?
17 A Well, that’s probably their interpretation, but it’s not
18 real. They probably think —
19 Q And that thinking that would convince them at least
20 relative to other variables to give it their best shot?
21 A I would think so, yes.
22 Q Despite that, sometimes people who are testing in high-
23 pressure situations like a law school admissions test or a
24 medical college entrance exam, do not wind up at their optimum
25 performance level; correct?
56
1 A I presume that’s correct.
2 Q And what explanations for that would do?
3 A Again, we just went through some of them. They have a
4 cold, they’re worried about money, they have stress at home,
5 they have stress on the job, I mean, there are all kinds of
6 events that could influence particular effort on a particular
7 day.
8 Q Or actually the stress of the test itself?
9 A Well, yes, of course. There’s some people who don’t do
10 well on tests.
11 Q And there are some people who do worse the more the
12 pressure is?
13 A Right. It’s not really the pressure; it’s how the patient
14 manages the pressure that’s the issue.
Now as we consider this long introduction in the context of the search for “relative weaknesses”, what does that mean? What if our test subject was only using the gym class effort level, versus the conference meet effort level? Can we make statistical comparisons then? Or should we compare that performance to how people do in gym class, and not comparing how they do in more stimulating environments?
Neuropsychology is a science, right? They should have control out all of these variables, right? Guess again, not because they don’t want to, but because they are dealing with human beings, and in brain injury evaluations, human beings who prevented from doing what they are presumed to do, based upon the precise disability for which we are evaluating them: brain damage.
Next: The Scope of the Problem for Brain Injured Person in Giving Consistent Best Effort.
Best Performance Method in Neuropsychological Assessment
There are two fundamental premises upon which the statistical application of the science of neuropsychology is based: The first is that a determination can be made of what a given individual’s premorbid abilities were. The second is that an individual is giving consistent best effort throughout the test battery. Neither assumption works perfectly, but the extent to which these two assumptions work well enough, will determine whether legitimate statistical based diagnostic conclusions can be incorporated into the assessment. In today’s blog, we will discuss the Premorbid Ability assumption. In tomorrow’s, the consistent best effort issue.
Premorbid ability. By premorbid ability, we mean a given individuals abilities prior to the onset of the accident or disease process. If no assumptions can be made about premorbid ability, no diagnosis about “cause” can be made by a neuropsychologist. All they are capable of saying is that a given individual has certain weaknesses and disabilities, but no definitive diagnosis can be made. Thus, some method of assessing premorbid ability is essential.
Most neuropsychologists don’t look at enough information in determining pre-morbid IQ. They base far too much of their assessment with respect to pre-morbid ability on the test battery itself. In our earlier example of the person with the IQ of 135 post the accident, that is less of a problem. Clearly a person who has a post-morbid IQ of 135, was very superior before the onset. But most cases are not so clear cut. A previously brilliant person may not continue to have a very superior IQ after the accident. If certain deficits bring the person down into an IQ range of 110 or so, we would likely need to look for other evidence to determine IQ.
One way is by looking at the areas where they still have strengths. If their average scores are in the 130 or above area, and there are a few scores in areas we might suspect would be effected by the injury, then it might be easy to say this person was very superior before. But again, that is the easy pattern to spot. Most profiles are not that obvious.
Another method is to look at certain subtest scores, where it is believed that a given ability is unlikely to be substantially effected by the given injury. Reading scores are often thought to be an ability that is rarely changed significantly by a mild or moderate injury. Thus, a neuropsychologist might say that a person with a “very superior” reading score and a much lower current IQ, had pathological deficits, based on the retained ability to read at a high level.
All of these methods work far better with someone with a very high IQ. When you are dealing with people in the average range, IQ’s of 90-110, it becomes much more difficult to make such assumptions about premorbid IQ from subtest scores.
Another method is to assume IQ based on a assessment of that person’s educational level. So a person with a college degree would be assumed to have a higher IQ than someone without. The obvious flaw in such logic, that some brilliant people don’t go to college, isn’t even the most significant problem. The significant problem is that it groups all college graduates together. Ask anyone who went to college. Not all of their classmates were of equal intelligence and ability.
Another method, one I believe to be considerably better than the first two, is called the ‘best performance method.” The best performance method is based upon the assumption that a person’s highest areas of achievement are the best indicators of premorbid ability. If these areas of highest achievement are in contrast to significantly lower subtests scores that may point to pathology.
Of course, there is considerable disagreement as to how to apply the “best performance method.” Many neuropsychologists dismiss it as they interpret this method as applying only to the best performance on individual tests, within the full battery of tests. That would mean if the person got 99% in arithmetic or vocabulary, that would mean that such person is in the 99%. It is easy to poke holes in a restricted use of the “best performance method” because we all have normal variances in what we are good at.
However, another interpretation of the best performance method is that it makes a full assessment – not just of the scores on the given battery of tests – but also the person’s real world performances or achievements. For example, if a person has graduated from medical school, one assumes that they are very near the top of the pre-morbid ability level. Likewise, if they have risen to the top of any profession, they would be assumed to be near the top.
In my opinion, the overall preferred method, which of course is harder to reduce to statistical probabilities, is to use of the real world “best performance method”. Such method considersall factors, school records, work performance records, areas of retained strength on the test. If someone got a math score of 700 and a verbal score of 700 on the SAT when applying to college, they clearly were way above average at that time. If they went on to graduate from a competitive law school or medical school, we must almost assume that they were at the superior or likely very superior level.
If the scores were good, but not great, if they graduated from college with more than a B average and went on to have a successful career, we can’t assume they were only average. Whether they are high average or superior is open to interpretation but that is what professionals are supposed to do: make subjective interpretations of complex multi-faceted variables, to reach conclusions.
Who a person was before injury is far more complex than how well they do now on a reading score. Only if neuropsychologists look at not the basic outline of a person’s premorbid life, but level of achievement within that life, will neuropsychology be able to identify the true areas of acquired deficits and disability.
Tomorrow the concept of “consistent best effort.”
Premorbid ability. By premorbid ability, we mean a given individuals abilities prior to the onset of the accident or disease process. If no assumptions can be made about premorbid ability, no diagnosis about “cause” can be made by a neuropsychologist. All they are capable of saying is that a given individual has certain weaknesses and disabilities, but no definitive diagnosis can be made. Thus, some method of assessing premorbid ability is essential.
Most neuropsychologists don’t look at enough information in determining pre-morbid IQ. They base far too much of their assessment with respect to pre-morbid ability on the test battery itself. In our earlier example of the person with the IQ of 135 post the accident, that is less of a problem. Clearly a person who has a post-morbid IQ of 135, was very superior before the onset. But most cases are not so clear cut. A previously brilliant person may not continue to have a very superior IQ after the accident. If certain deficits bring the person down into an IQ range of 110 or so, we would likely need to look for other evidence to determine IQ.
One way is by looking at the areas where they still have strengths. If their average scores are in the 130 or above area, and there are a few scores in areas we might suspect would be effected by the injury, then it might be easy to say this person was very superior before. But again, that is the easy pattern to spot. Most profiles are not that obvious.
Another method is to look at certain subtest scores, where it is believed that a given ability is unlikely to be substantially effected by the given injury. Reading scores are often thought to be an ability that is rarely changed significantly by a mild or moderate injury. Thus, a neuropsychologist might say that a person with a “very superior” reading score and a much lower current IQ, had pathological deficits, based on the retained ability to read at a high level.
All of these methods work far better with someone with a very high IQ. When you are dealing with people in the average range, IQ’s of 90-110, it becomes much more difficult to make such assumptions about premorbid IQ from subtest scores.
Another method is to assume IQ based on a assessment of that person’s educational level. So a person with a college degree would be assumed to have a higher IQ than someone without. The obvious flaw in such logic, that some brilliant people don’t go to college, isn’t even the most significant problem. The significant problem is that it groups all college graduates together. Ask anyone who went to college. Not all of their classmates were of equal intelligence and ability.
Another method, one I believe to be considerably better than the first two, is called the ‘best performance method.” The best performance method is based upon the assumption that a person’s highest areas of achievement are the best indicators of premorbid ability. If these areas of highest achievement are in contrast to significantly lower subtests scores that may point to pathology.
Of course, there is considerable disagreement as to how to apply the “best performance method.” Many neuropsychologists dismiss it as they interpret this method as applying only to the best performance on individual tests, within the full battery of tests. That would mean if the person got 99% in arithmetic or vocabulary, that would mean that such person is in the 99%. It is easy to poke holes in a restricted use of the “best performance method” because we all have normal variances in what we are good at.
However, another interpretation of the best performance method is that it makes a full assessment – not just of the scores on the given battery of tests – but also the person’s real world performances or achievements. For example, if a person has graduated from medical school, one assumes that they are very near the top of the pre-morbid ability level. Likewise, if they have risen to the top of any profession, they would be assumed to be near the top.
In my opinion, the overall preferred method, which of course is harder to reduce to statistical probabilities, is to use of the real world “best performance method”. Such method considersall factors, school records, work performance records, areas of retained strength on the test. If someone got a math score of 700 and a verbal score of 700 on the SAT when applying to college, they clearly were way above average at that time. If they went on to graduate from a competitive law school or medical school, we must almost assume that they were at the superior or likely very superior level.
If the scores were good, but not great, if they graduated from college with more than a B average and went on to have a successful career, we can’t assume they were only average. Whether they are high average or superior is open to interpretation but that is what professionals are supposed to do: make subjective interpretations of complex multi-faceted variables, to reach conclusions.
Who a person was before injury is far more complex than how well they do now on a reading score. Only if neuropsychologists look at not the basic outline of a person’s premorbid life, but level of achievement within that life, will neuropsychology be able to identify the true areas of acquired deficits and disability.
Tomorrow the concept of “consistent best effort.”
Understanding Neuropsychological Statistics in Diagnosing Brain Injury
Yesterday’s blog threw out a few numbers to illustrate some basic starting principles about neuropsychology. As an aid to our further discussion of this neuropsychology, today I will give some basic numerical principles to help in further understanding the numeric part of neuropsychological assessment.
First, neuropsych scores are typical given in one of three scoring methods: Standard score, percentile score and T scores. T scores are a little bit too complicated to try to explain to a laymen, so I will limit this discussion to standard scores and convert them to percentile scores.
Most people are somewhat familiar to standard scores, because IQ’s are given in them. Yesterday I used the example of our successful professional who had a post accident IQ of 135. An IQ of 100 is perfectly in the middle. Something below 70 is evidence of significant impairment. Each time you move down the standard score grid by 10 points, it represents a significant drop.
Here are the basic categories of Standard scores, with their percentile equivalents.
Very superior — 130 and above — 98% and above
Superior __ 120 to 129 — 92% to 97%
High Average — 110 to 119 — 76% to 91%
Average — 90 to 109 — 25% to 75%
Low Average — 80 to 89 — 8% to 24%
Borderline — 70 to 79 — 3% to 7%
Impaired — below 70 — 2% and below
T scores use the same basic concept, and again using 10 points as the break point, but with a T score, the mid point is 50. Some neuropsychologists may disagree as to the exact point that separates these categories, but this is certainly representative of the concept.
The second term to understand in terms of understanding the statistical analysis done by a neuropsychologist is the concept of “deviations”. While I am incapable of synthesizing the dozens of different explanations of this concept into one cohesive definition, in essence, when you move from one category like very superior, to superior, you have moved one deviation. When you move from very superior to high average, that would be two deviations. Movements of two deviations are deemed to be significant.
Yesterday’s example of an IQ score of 135, which was very superior, to an average processing speed score of 100, is a movement of three standard deviations. That could be quite significant, but of course is only one factor to be looked at in doing a full blown “assessment.”
Tomorrow: assessing premorbid IQ and other ability levels.
First, neuropsych scores are typical given in one of three scoring methods: Standard score, percentile score and T scores. T scores are a little bit too complicated to try to explain to a laymen, so I will limit this discussion to standard scores and convert them to percentile scores.
Most people are somewhat familiar to standard scores, because IQ’s are given in them. Yesterday I used the example of our successful professional who had a post accident IQ of 135. An IQ of 100 is perfectly in the middle. Something below 70 is evidence of significant impairment. Each time you move down the standard score grid by 10 points, it represents a significant drop.
Here are the basic categories of Standard scores, with their percentile equivalents.
Very superior — 130 and above — 98% and above
Superior __ 120 to 129 — 92% to 97%
High Average — 110 to 119 — 76% to 91%
Average — 90 to 109 — 25% to 75%
Low Average — 80 to 89 — 8% to 24%
Borderline — 70 to 79 — 3% to 7%
Impaired — below 70 — 2% and below
T scores use the same basic concept, and again using 10 points as the break point, but with a T score, the mid point is 50. Some neuropsychologists may disagree as to the exact point that separates these categories, but this is certainly representative of the concept.
The second term to understand in terms of understanding the statistical analysis done by a neuropsychologist is the concept of “deviations”. While I am incapable of synthesizing the dozens of different explanations of this concept into one cohesive definition, in essence, when you move from one category like very superior, to superior, you have moved one deviation. When you move from very superior to high average, that would be two deviations. Movements of two deviations are deemed to be significant.
Yesterday’s example of an IQ score of 135, which was very superior, to an average processing speed score of 100, is a movement of three standard deviations. That could be quite significant, but of course is only one factor to be looked at in doing a full blown “assessment.”
Tomorrow: assessing premorbid IQ and other ability levels.
Neuropsychological Assessment to Establish Brain Injury
In yesterday’s blog, I talked about the essentials prerequisites to proving to a jury that a plaintiff is disabled by brain injury. I said there:
Neuropsychologist: is a not an M.D., but a Ph.D. in psychology, who has typically finished a post doctoral fellowship and training in neuropsychology, which is essentially the field of brain behavior and assessment.
Neuropsychological assessment begins with the administration of a battery of psychometric tests. Then the neurospcyhologist will do an analysis of the pattern of the test scores, the clinical interview of the patient and known potential traumatic or disease processes, to make an assessment as to what pathology may exist in the brain, and from what potential causes.
Discrepancy analysis is the technical, statistical analysis of the neuropsychological test battery to determine whether there are relative weaknesses in an intraindividual comparison, upon which conclusions about pathology can be made.
An intraindividual comparison is a method of determining whether or not a portion of a brain is performing abnormaly for that person, based on the pattern of tests scores, primarily within the specific battery of tests that are being performed at that time.
A relative weakness is a test score on a specific test within the battery where the score is sufficiently lower than other tests, that it shows that a particular part of the brain may be functioning in a pathologically changed way.
All of these technical terms and approaches are usually necessary because only in rare cases does an individual have previous neuropsychological assessments that precede their injury or disease. It is thru these technical approaches to evaluations, that a neuropsychologist can make determinations of pathology, without prior batteries to contrast current testing with.
To demonstrate how the statistical part of the assessment would work lets assume a simple example – focusing on a small part of the test battery. Let us assume we are assessing a very smart professional, who had excelled throughout his or her academic life, obtaining an advanced degree and always testing at the high end of all standardized tests.
One of the key elements to all neuropsychological assessments is the administration of the IQ test. Our hypothetical individual does as expected and receives an IQ score of 135, which is considered very superior. (More on the categories of achievement levels in tomorrow’s blog.) In contrast, when given tests which measure this individuals processing speed, the score was 100, which is still average, but is more than 35 points lower than the IQ score. If this person’s processing speed was compared to all individual’s, the score would be considered normal. But if Discrepancy Analysis is used to make an intraindividual comparison of the IQ score to the processing speed score, that person would be found to have a relative weakness. That relative weakness could begin to form the basis of an opinion about pathology, and perhaps pathology related to a specific event.
The key issue in engaging in formal discrepancy analysis would be a determination of how rare it is for someone with a 135 IQ to have a 35 point difference between that score and the processing speed.
One piece of this puzzle that most neuropsychologists would not mention, but I personally find significant, is that if this individual had consistently been in the top few percentiles on standardized testing, we can almost presume that they were capable of fast thinking. If you don’t think fast, you don’t get high scores on college or graduate school admissions tests.
But my practical approach contrasted to the technical approach of most neuropsychologists, is symptomatic of another major schism in the field: the method used to determine pre-morbid (pre-injury or disease) abilities.
More on these issues later this week.
- “Now, we have more cases than we did in 1996 where the neuroimaging is abnormal. Yet, we still must show the same things: an accident with the potential to injure the brain, acute evidence that the brain was injured, deficits that can be determined in how a person functions and a CHANGED PERSON. Neuroimaging adds to the equation, but doesn’t eliminate any of the other issues. The only thing I would seriously change from what I said in 1996 is that there are other ways in addition to neuropsychological assessment, that deficits in ways in which the brain are working, can be identified.”
Neuropsychologist: is a not an M.D., but a Ph.D. in psychology, who has typically finished a post doctoral fellowship and training in neuropsychology, which is essentially the field of brain behavior and assessment.
Neuropsychological assessment begins with the administration of a battery of psychometric tests. Then the neurospcyhologist will do an analysis of the pattern of the test scores, the clinical interview of the patient and known potential traumatic or disease processes, to make an assessment as to what pathology may exist in the brain, and from what potential causes.
Discrepancy analysis is the technical, statistical analysis of the neuropsychological test battery to determine whether there are relative weaknesses in an intraindividual comparison, upon which conclusions about pathology can be made.
An intraindividual comparison is a method of determining whether or not a portion of a brain is performing abnormaly for that person, based on the pattern of tests scores, primarily within the specific battery of tests that are being performed at that time.
A relative weakness is a test score on a specific test within the battery where the score is sufficiently lower than other tests, that it shows that a particular part of the brain may be functioning in a pathologically changed way.
All of these technical terms and approaches are usually necessary because only in rare cases does an individual have previous neuropsychological assessments that precede their injury or disease. It is thru these technical approaches to evaluations, that a neuropsychologist can make determinations of pathology, without prior batteries to contrast current testing with.
To demonstrate how the statistical part of the assessment would work lets assume a simple example – focusing on a small part of the test battery. Let us assume we are assessing a very smart professional, who had excelled throughout his or her academic life, obtaining an advanced degree and always testing at the high end of all standardized tests.
One of the key elements to all neuropsychological assessments is the administration of the IQ test. Our hypothetical individual does as expected and receives an IQ score of 135, which is considered very superior. (More on the categories of achievement levels in tomorrow’s blog.) In contrast, when given tests which measure this individuals processing speed, the score was 100, which is still average, but is more than 35 points lower than the IQ score. If this person’s processing speed was compared to all individual’s, the score would be considered normal. But if Discrepancy Analysis is used to make an intraindividual comparison of the IQ score to the processing speed score, that person would be found to have a relative weakness. That relative weakness could begin to form the basis of an opinion about pathology, and perhaps pathology related to a specific event.
The key issue in engaging in formal discrepancy analysis would be a determination of how rare it is for someone with a 135 IQ to have a 35 point difference between that score and the processing speed.
One piece of this puzzle that most neuropsychologists would not mention, but I personally find significant, is that if this individual had consistently been in the top few percentiles on standardized testing, we can almost presume that they were capable of fast thinking. If you don’t think fast, you don’t get high scores on college or graduate school admissions tests.
But my practical approach contrasted to the technical approach of most neuropsychologists, is symptomatic of another major schism in the field: the method used to determine pre-morbid (pre-injury or disease) abilities.
More on these issues later this week.