Category: Brain Injury; Neuroplasticity (includes neuroscience); Neurodegenerative Disease (e.g. MS, Parkinson's disease)
Objective : The objective was to investigate the neurocognitive profile of TBI-related reading deficits. We evaluated and compared reading and neuropsychological performance in a sample of TBI patients and neurologically healthy controls.
Design : The study design consisted of a survey of TBI clinical features, specifically performance on reading and neuropsychological tasks.
Setting : Data were collected and analyzed at the War Related Illness and Injury study Center, a secondary evaluation clinic at VA Palo Alto Healthcare System (VAPAHCS).
Participants (or Animals, Specimens, Cadavers) : Participants consisted of a convenience sample of 67 adults. Thirty-seven were patients with mild-to-moderate TBI (25 Male; 12 Female; M Age: 44) recruited from the War-Related Injury and Illness Study Center (WRIISC) and the Santa Clara Valley Medical Center. Another 30 were neurologically healthy controls (15 Males; 15 Females; M Age: 39) recruited from the surrounding community.
Interventions : Not applicable.
Main Outcome Measure(s) :
All participants completed a battery of neuropsychological tests and questionnaires including the OSU TBI-ID, MMSE, CVLT-II, WAIS Digit Span, WTAR, TMT – A & B, and the RBANS. Participant reading rates were quantified using the Pepper Visual Skills for Reading Test (VRST), the Test of Word Reading Efficiency (TOWRE), and the International Reading Speed Texts (IReST). We hypothesized measures of reading fluency would correlate with neuropsychological subtests.
Results : We conducted t-tests and correlations on the data using the RBANS sub-tests, the Visual Skills Reading Test (VSRT), Test of Word Reading Efficiency (TOWRE), and the International Speed Reading Texts (IReST). T-tests showed controls had significantly better scores than TBI patients. Pearson's correlations demonstrated that RBANS performance is correlated with reading rate. We also conducted multiple linear regression analyses using the measures of reading rate (VSRT, TOWRE, IReST) as outcomes and Age, Education, and the RBANS subtests as predictors. We found RBANS contributed variance to the model beyond Age and Education. Analysis of the sub-tests demonstrated the language and attention subtests were significant.
Conclusions : These results indicate that reading rate is associated with cognitive abilities unrelated to eye movement. Though traumatic brain injury may hamper eye movement, it is likely a general cognitive slowing also contributes to diminished reading fluency. Future work will attempt to connect these results to diffusion tensor imaging (DTI) data which quantifies the integrity of white matter pathways.
Keith Main– Principal Scientist, Defense and Veterans Brain Injury Center, Silver Spring, Maryland
Maheen Adamson– Senior Scientific Research Director/Clinical Associate Professor, DVBIC, VA Palo Alto/Neurosurgery, Stanford School of Medicine, Palo Alto, California