Updating Memory after Mild Traumatic Brain Injury and Orthopedic Injuries

Abstract

Few studies have examined the trajectory of recovery of executive function (EF) after mild TBI (mTBI). Therefore, consensus has not been reached on the incidence and extent of EF impairment after mTBI. The present study investigated trajectory of change in executive memory over 3 months after mTBI on 59 right-handed participants with mTBI, as defined by Centers for Disease Control criteria, ages 14-30 years, recruited within 96 hours post-injury and tested <1 week (baseline), 1 month, and 3 months after injury. Also included were 58 participants with orthopedic injury (OI) and 27 typically developing (TD) noninjured participants with similar age, socioeconomic status, sex, and ethnicity. MRI data were acquired at baseline and 3 months. Although criteria included a normal CT scan, lesions were detected by MRI in 19 mTBI patients. Participants completed the KeepTrack task, a verbal recall task placing demands on goal maintenance, semantic memory, and memory updating. Scores reflected items recalled and semantic categories maintained. The mTBI group was divided into two groups: high (score ‡ 12) or low (score < 12) symptoms based on the Rivermead Post-Concussion Symptoms Questionnaire (RPQ). Mixed model analyses revealed the trajectory of change in mTBI patients (high and low RPQ), OI patients, and TD subjects were similar over time (although the TD group differed from other groups at baseline), suggesting no recovery from mTBI up to 90 days. For categories maintained, differences in trajectory of recovery were discovered, with the OI comparison group surprisingly performing similar to those in the mTBI group with high RPQ symptoms, and different from low RPQ and the TD groups, bringing up questions about utility of OIs as a comparison group for mTBI. Patients with frontal lesions (on MRI) were also found to perform worse than those without lesions, a pattern that became more pronounced with time.

Whiplash Injury and Mild Traumatic Brain Injury: Differential Effects on Cognitive Functioning?

“…The outcome of the study is compatible with findings from other studies. However, in contrast to previous studies [1,13,16,17,19,[20][21][22][23], the MTBI patients showed no significantly reduced speed of information processing as was evaluated with the PASAT. An overview of the results of this study can be seen in Table 1.…”

“…In MTBI patients, mild impairments in speed of information processing, (sustained, divided, focused and/or alternating) attention and (auditory-verbal and/or visuospatial) memory have been found [1,13,16,17,19,[20][21][22][23]. With regard to memory, most patients displayed deficits concerning the storage of new information into memory and/ or the reproduction of recently learned information from memory.…”

“…According to some authors [22,[30][31][32], the majority of these lesions are mainly focal because they are localized in the white matter of the frontal and temporal (limbic) lobes.…”

“…With regard to cognitive functioning, WI and MTBI patients often complain of poor attention and memory [7]. Several studies have looked for objective findings concerning cognitive dysfunctions after WI [1,2,[8][9][10][11][12][13][14][15] and MTBI [16][17][18][19][20][21][22][23] and have found the presence of only mild cognitive deficits, if any, in both patient groups, mainly in the domain of attention, information processing and memory.…”

Prevalence and Predictors of Poor Recovery from Mild Traumatic Brain Injury

“…For a complete description of the sample and all study procedures, see Hanten and associates 29 ; only procedures relevant to the present analysis are described below. Neuropsychological measures included the Brief Visual Memory Test-Revised 30 immediate recall (BVMT-R Total), the Verbal Selective Reminding Test 31,32 including the number of words recalled after a delay (VRST Delay) and number of words continuously recalled (VSRT CLTR), and the Symbol-Digit Modalities Test 33 oral (SDMT-O) and written (SDMT-W) administrations.…”