RUSSELL M. BAUER, PH.D.JUNE 30 , 2014

Forensic Neuropsychology in Personal Injury Cases I

Compensation for Mental Injury

law in this area is called “tort” law in the case of civil proceedings

governs compensation of individuals whose interests have been violated

recognizes potential fault or negligence of injured party

Neuropsychologists generally not concerned with liability; “damages” is the focus

personal injury vs. worker’s compensation

Tort Law vs. Worker’s Compensation

WC handled administratively; tort law handled judicially

WC regulated by legislature; tort law by the courts

WC compensates according to fixed injury schedule according to earning capacity; tort law is theoretically limitless (e.g., pain and suffering, loss of consort, etc.)

Worker’s Compensation

designed to compensate injured workers for losses, incurred during the course of employment, in their wage-earning power

actually the result of a different set of guidelines than “tort” law

designed to allow workers to circumvent frequently used employer defenses: contributory negligence you assumed the risk another employee (who can’t pay you salary and

benefits) was responsible

Worker’s Compensation Criteria

an injury or disability affecting wage-earning capacity facial disfigurement, loss of sexual potency

doesn’t countarising out of or in the course of, employment

assumes causal relationship positional risk (injury would not have occurred

“but for employment”)which is “accidental”

some nonaccidents are compensable

Procedures for WC Claims

Employee serves noticeMedical examinationProceeding for Adjustment and Compensation

administrative hearing before hearing officer once settled, claimant can’t take case to court for

further action

Mental Injury

Physical Trauma Causing Mental InjuryMental Stimulus Causing Physical InjuryMental Stimulus Causing Mental Injury

Key Elements of Tort Law

act or omission + causation + fault + protected interest + damage = liability

existence of duty owed the plaintiff by the defendant

violation of duty by the defendantan injury “proximately caused” by the

violation, andthe injury is compensable

Duty

“an obligation, to which the law will give recognition, to conform to a particular standard of conduct toward another”

we have certain duties, for example, when we Drive a car Handle firearms Maintain our homes Etc.

Obligation

Something you MUST do because of a law, rule, promise, etc.

Not fulfilling obligation (violation) can be by act (commission) or by omission

can be intentional or negligentnegligence is “conduct which falls below the

standard of care established by law for the protection of others against reasonable risk of harm”

Proximate Cause

given the actions of A, could one reasonably foresee the consequences that occurred?

alternative: but for the actions/omissions of A, event/consequences would not have occurred

most psychological theories have elaborate cause-effect chains

courts will generally recognize only certain aspects in the chain of events as proximate causes

Compensable Damages

an invasion of “legally protected interests”“feeling of harm” not sufficient; law must define

interests as sufficiently important or worthy of protection to hold the person causing harm liable for damages

major importance of neuropsychological testimony is in this area; extent of neuropsychological injury

Compensatory damages: replace what is lostPunitive damages: punish offender as a deterrent

for future action

Mental Injury and Tort Law

reluctance to compensate “mental injuries” without some physical manifestation

basic mental injury torts: tort of intentional infliction (e.g., slander) tort of negligent infliction (e.g., residents

emotionally affected by flood damage)the “predisposed plaintiff”the “as they are” principle

Predisposed Plaintiff: Aggravation

Castillo v. Young – plaintiff with TMJ injury and pre-existing TMJ condition from previous injury

Physician testimony: “There are patients – it's like a truck. If you rear end a truck that’s full of bricks, you’re probably

[not] going to hurt your truck – you’re going to hurt yourself, not the truck. If you rear end a truck full of eggs, you’re more likely to do damage than if you rear end a truck full of bricks. Unfortunately I think in [Castillo’s] case, they rear-ended her being full of eggs. She was fragile. . . . Any time you’ve had injury to a joint that would cause fracture of that bone, there has to be consequence to the system, whether there [are] symptoms provoked at that time or not.”

Eggshell jury instructions proposed (but denied): There is evidence that the Plaintiff had broken her jaw in 1983 and experienced a disk

displacement in her jaw prior to the December 20, 2000, accident. The Defendant(s) is liable only for any damages that you find to be proximately caused by the Defendants' negligence relating to the December 20, 2000, accident. If you cannot separate damages caused by the pre [sic] existing broken jaw from those caused by the accident of December 20, 2000, then the Defendant(s) are liable for all of those damages.

Plaintiff awarded $13,058.67. Appealed to State Supreme Court, which opined that the eggshell jury instructions SHOULD have been given, and remanded the case for retrial

Issues in Evaluation

potential examiner bias (in both directions)retrospective analysis of prior mental

functioning often critically importantissue in damages: can the individual

function “as s/he was”?impact of mental/emotional reactions, some

of which are, themselves, compensableeffects of litigation, distortions, malingering

Definition of Mild TBI

Traumatically induced physiological disruption of brain function

At least one of the following:1. any period of loss of consciousness 2. any loss of memory for events immediately before or after the

accident 3. any alteration of mental state at the time of accident (e.g., feeling

dazed, disoriented, or confused) 4. Focal neurological deficit(s) that may or may not be transient

Exclusion Criteria:1. loss of consciousness exceeding approximately 30 minutes 2. after 30 minutes, a GCS falling below 13 3. post-traumatic amnesia (PTA) persisting longer than 24 hours

American College of Rehabilitative Medicine, 1993

Common Case Scenario in “Mild Head Injury”

• minor MVA with no or questionable LOC, PTA, but some indication of possible orthopedic injury

• normal ED evaluation• delayed development of “de novo” cognitive

problem (e.g., memory, concentration difficulty) • subsequent referral to a neurologist-

neuropsychologist • neuropsychological exam reveals abnormal

neuropsychological or neuropsychiatric test findings indicative of “brain damage”

What does the literature on MHI say What does the literature on MHI say about longabout long--term outcome?term outcome?

Dikmen, et al. (1995): studied 1-year outcome in 436 head injured and 121 general trauma controls– MHT has good outcome in vast majority (95%) of

patients Binder, Rohling & Larrabee (1997)

– used “d” - control group SD– used “g” - pooled SD of both groups– found very small effects of MHT

Effect Sizes in Prospective and Effect Sizes in Prospective and QuasiQuasi--Prospective NP StudiesProspective NP Studies

STUDY d Effect Hedges gEffect

MHTSample

ContSample

TSI

Ewing .737 .737 10 10 2.2yAlterman -.181 -.208 25 25 remoteHugenholz .466 .371 22 22 3mRuff 89 .260 .187 16 26 3mRuff 89 -.411 -.461 06 12 3mRuff 89 .317 .112 10 18Montgomery -.154 -.228 26 26 6mBornstein .278 .223 24 24 15yDikmen .019 .023 161 121 1yCremona-Meteyard 1

.821 .523 06 09 1y

Cremona-Meteyard 2

.444 .245 08 09 1y ormore

Binder, Rohling, & Larrabee, 1997 (JCEN, 19, 421-431)

P ossible P P V and N P V of N P D iagnosis P ossible P P V and N P V of N P D iagnosis --T B I P revalence of .05T B I P revalence of .05

Sensitivity Specificity P P V N P V.80 .88 .26 .99.90 .70 .14 .99.90 .90 .32 .99.70 .90 .27 .98.70 .80 .16 .98.70 .70 .11 .98

B inder, R ohling, & L arrabee, 1997 (JCEN, 19, 421-431)

Conclusions

Severe long-term sequelae of mild TBI are rare (<10%)

Mild TBI results in NP effect sizes that average less than .5 SD

NP evals in MHT have low PPVTherefore, some NP evaluations lead to “false

positive” diagnoses

Caveats (Bigler, 2001)

The “lesion” is always larger than visualizedNormal scans may not signify absence of

pathologyDOI scans may not be enoughLong-term sequelae (e.g., accelerated aging)

“Noninjury” Contributors to Neuropsychological Impairment in MHI

Adversarial patient-examiner relationshipExaggeration or poor effort

Impairment as communication Frank malingering for gain; financial incentives Factitious disorders

Fatigue, pain, other physical factorsPsychiatric disturbance (e.g., psychosis, anxiety,

depression)Pre-existing factors affecting neuropsychological

performance (e.g., learning disability, limited education)Occupational/life experience factors

Financial Incentives and Disability

Binder & Rohling (AJP, 1996, 153, 7-10) Meta-analytic review of financial incentives and

symptoms 18 study groups, 2,353 subjects Weighted mean effect size of difference between

groups with and without financial incentives was 0.47 More late-onset symptoms in groups seeking

compensation

Checks against False Positives: Consistency Analysis

Consistency of results between/within domains

Consistency with known syndromes example: “hemi-anomia”

Consistency with injury severityConsistency with other aspects of

behavior e.g. memory abilities during vs. apart from formal

testing

Post-Concussion Syndrome

Post-Concussion Syndrome: DSM-IV Definition

“acquired impairment in cognitive functioning, accompanied by specific neurobehavioral symptoms, that occurs as a consequence of closed head injury of sufficient severity to produce a significant cerebral concussion” (LOC, PTA, etc.)

Symptoms, cognition, balance

PCS: DSM-IV Criteria

A Hx of head trauma that has caused significant cerebral concussion

B Evidence from NP testing or quantified cognitive assessment of difficulty in attention or memory

C Three (or more) of the following occur shortly after trauma and last at least 3 months: easy fatigue disordered sleep headache dizziness/vertigo irritability or aggression with little/no provocation anxiety, depression, or affective lability changes in personality apathy or lack of spontaneity

PCS: DSM-IV Criteria (cont’d)

D. Symptoms begin after head trauma or else represent a worsening of pre-existing symptoms

E. Significant impairment in social or occupational function; decline from previous functional level

F. Do not meet criteria for dementia and are not better accounted for by another mental disorder

PCS-Like Complaints of NP Dysfunction

CommonNonspecific Potentially related to non-neurological factors

(anxiety, depression, fatigue, stress)Correlate better with distress than with

objective indicators of CNS injuryEasy to feign or exaggerate

Complaints as “Evidence”

In the absence of objective neuro-psychological deficit, complaints are often taken to indicate the existence of occult disease

There is a difference between symptoms (subjective evidence) and signs (objective evidence) of illness

Symptom reports subject to cognitive distortions and attributional processes

“She reports feeling tired, moving slowly, losing her balance, tripping over things, and feeling weak and dizzy. She also reported increased sensitivity to noise, altered perception of the ambient temperature (feeling warm when others are comfortable), poor concentration, forgetfulness, finding once routine activities now complicated, diminished sexual functioning, sleep problems, fatigue and low energy level, anxiety and nervousness, “panic attacks”, lack of patience, decline in handling household chores, fear of certain situations, decline in recreational activities, concerns and worried about her health, depressed mood, decline in her ability to work, diminished interest in pleasurable activities, weight gain of 55 pounds, feelings of worthlessness and guilt, difficulty with language and word-finding, difficulty with concentration and thought processing, difficulties with making conversation and understanding it, writing slowly and illegibly, finding it difficulty to get started on things, trouble making decisions, difficulty pronouncing words, forgetting people’s names, getting her mind off certain thoughts, misplacing things, and becoming easily distracted. Scattered and confused behavior permeates all aspects of her life. She also reports periods of time where she becomes completely disoriented to her place and purpose. She experiences severe headaches, shoulder, neck, back, and leg problems, severe depression and cognitive dysfunction”.

Complaints (N=45) as “Evidence”

Problems with Using Complaints as Evidence of MHI

Mittenberg et al. (1992, 1997): “expectation as etiology” ‘imaginary concussion’ produces symptom complaint

cluster identical to that reported by patients with ‘real’ head injury

patients with minor TBI significantly underestimate degree of pre-injury problems

Major PCS Symptoms

“Imaginary

concussion”

produces a pattern of symptom

reports virtually identical

to that seen after

MHI

MHT patients

significantly underestimate preinjury

symptoms compared to

a noninjured

control group

Base Rates of Post-Concussion Symptoms (Base Rates of Post-Concussion Symptoms (LarrabeeLarrabee,,1997, based on Lees-Haley & Brown, 1993)1997, based on Lees-Haley & Brown, 1993)

Symptoms Medical Controls Non-CNS Litigantsa

Headaches 62% 88%Fatigue 58% 79%Dizziness 26% 44%Blurred Vision 22% 32%Bothered by Noiseb 18%c 29%c

Bothered by Light - -Insomniab 52%d 92%d

Poor Concentration 26% 78%Irritability 38% 77%Loss of Temper - -Memory Problemsb 20% 53%Anxiety 54% 93%

aNon CNS Litigants: in litigation for emotional or industrual stress, but not for CNSinjuries, bsignificant difference from controls at 1m, but not 1y in Dikmen et al.,1986; c”hearing problems in Lees-Haley & Brown, 1993;d”sleeping problems in Lees-Haley & Brown, 1993

Conclusions

You don’t have to have had a head injury to have post-concussion symptoms

Once something bad has happened to you, you tend to attribute more of your problems to it

Complaints reflect the subjective, not necessarily the objective, consequences of MTBI

Implications for Understanding PCS5-8% of MHI patients have persistent deficitsPhysiogenic causes likely operative in the

first 1-3 monthsPsychogenic causes important (though

probably not exclusively so) thereafterComplaints have low specificity for MHIBaserate issues importantAttributional processes importantSuggests need for a scientific approach to

assessing persistent complaints after MHT