Page 90 - NNS 2014 Program & Abstract Book

The objective is to examine differences in symptoms endorsed by
mTBI patients who screen positive for post traumatic stress (PTSD)
versus those who do not.
Service members (n = 139) returning from Iraq and Afghanistan
receiving care in a 4-week intensive program at the National Intrepid
Center of Excellence were evaluated for neurological deficits using
the Neurobehavioral Symptom Inventory (NSI), PTSD using the
PTSD Checklist Military (PCLm), and measure of effort using the
Medical Symptom Validity Test (MSVT). The population was 95.7%
male, 36.20 – 8.3 years old, 14.78 – &.64 years in service, and
2.4 – 0.7 number of military deployments. All were > 6 months from
last TBI. PCLm total score ( ‡ 44) and presence/absence of DSM-IV
criteria for PTSD defined the PTSD positive group (PTSD + ; N = 92)
and a PTSD negative group (PTSD-, N = 47). NSI data were then
compared across groups. The top five symptoms endorsed by each
group were nearly identical: Forgetfulness (M = 3.01, SD = 0.94),
Difficulty sleeping (M = 2.89, SD = 1.10), Irritability ( M = 2.88,
SD = 0.94), Poor concentration (M = 2.79, SD = 0.95), and Slowed
thinking (M = 2.59, SD = 1.06). PTSD+ and PTSD- groups were
compared for individual NSI symptoms, and NSI factors (3 factor
model: Somatic/Sensory, Cognitive, & Affective; 4 factor model:
Physical, Cognitive, Affective, & Sensory).
Results showed that the differences between 19 of the 22 individual
NSI symptoms were statistically significant. Both NSI factor models
were significantly different between the PTSD + and PTSD- groups.
Results show that while forgetfulness, difficulty with falling sleep,
irritability, poor concentration, slowed thinking, and headache are the
top symptoms endorsed by both groups, the PTSD + group had sig-
nificantly greater severity of symptoms.
These findings suggest that PTSD + and PTSD- patients have
similar symptoms, but that PTSD + patients report greater severity. It
further supports that, although the presence of psychological co-
morbidity can worsen perceived symptoms following TBI, symptoms
from TBI alone can account for chronic disability in our service
members.
Key words
military, NSI, PTSD, trauma
B3-08
CONTROLLING CONFOUNDING EFFECTS IN MTBI VI-
SUAL TRACKING ASSESSMENT
Ghajar, J.1,2, Dodson, V.1, Seara, N.1, Modera, P.1, Rajashekar, U.1,
Hedges, J.H.1, Tong, J.1, Spielman, L.A.1 , Maruta, J.1
1Brain Trauma Foundation, New York, USA
2Stanford University School of Medicine, Stanford, USA
Attention can be impaired by mild traumatic brain injury (mTBI). We
have previously identified that attention impairments associated with
mild traumatic brain injury (mTBI) may be detected by quantifying
the performance of predictive visual tracking and comparing against
population norms. However, there may be confounding personal traits
that produce variations in performance norms, which interfere with
detection of abnormalities. We sought to better delineate the effects of
mTBI on visual tracking by considering factors that may influence
performance.
Eye movements during a circular visual tracking task were char-
acterized with indices of gaze-target synchronization and binocular
coordination. Possible influences of age and gender on these indices
were examined in the data from 139 normal adult subjects. Perfor-
mance characteristics of 9 patients with mTBI (tested 2 to 55 days
post-injury) were compared to the norms.
Within normal subjects, age (18–74 years) was not found to affect
performance but male gender was associated with higher smooth
pursuit velocity gain. Gender-adjusted norms changed the patients’
relative percentile standings such that, given similar smooth pursuit
velocity gains, the performance of a male patient can indicate a
greater deficit than that of a female patient.
The sensitivity of visual tracking indices to detect differences from
the norm needs to be adjusted for gender. Identification of other
factors that predict different performance norms is important. Sup-
port: W81XWH-08-1-0646, James S McDonnell Foundation.
Key words
assessment, concussion, neurocognitive outcome, ocular pursuit, post-
concussive syndrome, screening
B3-09
DISPLAY ENHANCED TESTING OF COGNITIVE IMPAIR-
MENT AND MILD TRAUMATIC BRAIN INJURY (DETECT):
A NOVEL TOOL FOR CONCUSSION ASSESSMENT
Espinoza, T.2, Phelps, S.E.3 , Wright, D.W.2, Bazarian, J.4 , Knezevic,
A.5, Gore, R.3,6, Ciaravella, N.M.2, Crooks, C.3, Liu, B.3, Smith, S.3,
LaPlaca, M.C.1
1Georgia Institute of Technology, Department of Biomedical En-
gineering, Atlanta, USA
2Emory University, Department of Emergency Medicine, Atlanta, USA
3Georgia Tech Research Institute, Atlanta, GA
4University of Rochester, Departments of Emergency Medicine,
Neurology, and Neurosurgery, Rochester, USA
5Emory University, Department of Biostatistics, Atlanta, USA
6Emory University, Department of Neurology, Atlanta, USA
Concussion remains difficult to diagnose due to the heterogeneity of
the injury and individual responses. Furthermore, current concussion
assessment methods are generally subjective and lack validation and
standardization. We developed a novel portable neuropsychological
platform—Display Enhanced Testing for Cognitive Impairment and
Traumatic Brain Injury (DETECT)—to deliver abbreviated, objective
neurocognitive tests under immersive conditions to assess reaction
time and working memory. We used DETECT to assess cognitive
function in two high school and two college football teams over the
course of a season (n = 131 subjects). Players were administered
baseline DETECT tests and tested immediately following suspected
concussions. During the study, 14 subjects had confirmed head im-
pacts and were diagnosed with concussion by a certified athletic
trainer or team physician. Choice reaction time, measured using a
shape recognition task, was longer post-concussion as compared to
baseline (95% mean CL: 0.1, 6.9; p = 0.05); moreover, concussed
subjects were less accurate on this task (mean percent correct decrease
of 6.1%; 95% mean CL: - 10.9, - 1.3; p = 0.02). Performance on
delayed word recall after a concussion also worsened compared to
baseline (mean percent correct decrease of 8.7%; 95% mean CL: - 15.5,
- 1.8; p = 0.02). Further data analysis is in progress and will examine
other performance metrics within DETECT across all subjects.
DETECT may offer a substantive advancement in the ability to offer
a more sensitive sideline tool for cognitive assessment following
suspected concussion in athletes as well as other situations where
prompt objective cognitive triage is needed. Funded by DoD
W81XWH-12-C-0203.
Key words
athletics, concussion, mTBI, neurocognitive, neuropsychological test,
reaction time
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