Traumatic Brain Injury
Conditions
Keywords
cognitive training, neuroplasticity, cognitive impairment, recovery of function, memory, attention
Brief summary
The investigators evaluated whether it was possible to improve the measurement of memory, attention, and executive function in patients who have suffered traumatic brain injury through the use of computer-based testing. Note: the original design of the study was altered due to failure to recruit sufficient numbers of patients who were willing to undergo prolonged cognitive training.
Detailed description
Here we describe a series of computer-based tests that were used to evaluate memory, attention, and executive function in large groups of control subjects and in patients with chronic mild and moderate/severe TBI. This extensive battery of neuropsychological tests (NPTs) and subjective rating scale measures were obtained at study entry from the TBI cohort. NPT and rating scale data were compared to those obtained from control subjects to characterize the cognitive deficits following mild, moderate and severe TBI. . Normative data were obtained by regressing the influences of age, education, and computer use on scores to create normed z-scores on different NPTs,. We hypothesized that patient with TBI would show deficits on tests of memory, attention, and executive function relative to their predicted z-scores (based on the aforementioned regression functions) and that deficits would be more pronounced in patients with severe TBI than in patients with mild TBI.
Interventions
BEHAVIORALDigit span testing
Testing of short-term verbal memory with digit span
BEHAVIORALSpatial span testing
Testing of short-term visuospatial memory with spatial span.
BEHAVIORALFinger tapping
Testing motor speed with a finger tapping test.
BEHAVIORALSimple reaction time
Testing the time to respond to the appearance of a visual stimulus.
BEHAVIORALChoice reaction time
Testing the time needed to discriminate and respond to different visual stimuli.
BEHAVIORALVerbal fluency
Evaluating how many words are produced in 90s.
BEHAVIORALVerbal list learning
Evaluating short-term memory, learning, and memory interference in the recall of 12-word lists, presented three times. Evaluating long-term memory and recognition after a 20 min interval.
BEHAVIORALTrail making test
Evaluating visuomotor speed and executive function in Trail Making Tests, A and B. In the first, subjects connect successive numbers with the mouse. In the second, they connect numbers and letters in alternation.
BEHAVIORALDesign fluency
Subjects create the maximal number of 4-line patterns in 90 s.
BEHAVIORALQuestionnaire completion
Question completion time is measured on each question of the Post-Traumatic Stress Disorder check list (PCL) and on the cognitive failures questionnaire.
Sponsors
US Department of Veterans Affairs
Study design
Observational model
ECOLOGIC_OR_COMMUNITY
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to 78 Years
Healthy volunteers
Yes
Inclusion criteria
Control subjects were required to meet the following inclusion criteria: * (a) fluency in the English language * (b) no current or prior history of bipolar disorder, mania, or schizophrenia * (c) no current substance abuse * (d) no concurrent history of neurologic disease known to affect cognitive functioning * (e) on a stable dosage of any required medication * (f) auditory functioning sufficient to understanding normal conversational speech and visual acuity normal or corrected to 20/40 or better
Exclusion criteria
* History of TBI
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Performance in TBI Patients and Controls | Subjects were tested in a single 2-hr session. | Subjects were assessed on a set of cognitive tests. Here we describe the results on the simple reaction time test in which subjects respond as rapidly as possible to the computer-controlled occurrence of a visual stimulus by pressing a mouse button. Two control groups were used. One large control group underwent a single test to provide data from subjects with a broad range of age and education. The other, smaller, control group underwent three tests at weekly intervals to evaluate the test-retest reliability of the measure. |
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Control Subjects Control subjects = 230. Normal control subjects of various ages. | 237 |
| TBI Patients TBI patients N = 30. Mixed mild and severe TBI group, with most showing PTSD comorbidity. | 28 |
| Total | 265 |
Baseline characteristics
| Characteristic | TBI Patients | Control Subjects | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 15 Participants | 15 Participants |
| Age, Categorical Between 18 and 65 years | 28 Participants | 222 Participants | 250 Participants |
| Age, Continuous | 42.4 years STANDARD_DEVIATION 10.3 | 41.0 years STANDARD_DEVIATION 21.3 | 41.8 years STANDARD_DEVIATION 14.4 |
| Region of Enrollment United States | 28 participants | 237 participants | 265 participants |
| Sex: Female, Male Female | 1 Participants | 107 Participants | 108 Participants |
| Sex: Female, Male Male | 27 Participants | 130 Participants | 157 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 237 | 0 / 28 |
| serious Total, serious adverse events | 0 / 237 | 0 / 28 |
Outcome results
Primary
Performance in TBI Patients and Controls
Subjects were assessed on a set of cognitive tests. Here we describe the results on the simple reaction time test in which subjects respond as rapidly as possible to the computer-controlled occurrence of a visual stimulus by pressing a mouse button. Two control groups were used. One large control group underwent a single test to provide data from subjects with a broad range of age and education. The other, smaller, control group underwent three tests at weekly intervals to evaluate the test-retest reliability of the measure.
Time frame: Subjects were tested in a single 2-hr session.
Population: Data from two TBI patients were excluded due to suspected suboptimal effort.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Simple Reaction Time Test | Performance in TBI Patients and Controls | Control group 1, n=189 | 237.8 ms | Standard Deviation 27.8 |
| Simple Reaction Time Test | Performance in TBI Patients and Controls | Control group 2, n =48 | 231.5 ms | Standard Deviation 17.72 |
| Simple Reaction Time Test | Performance in TBI Patients and Controls | Mild TBI, n =22 | 228.0 ms | Standard Deviation 34.6 |
| Simple Reaction Time Test | Performance in TBI Patients and Controls | Severe TBI, n =4 | 280.0 ms | Standard Deviation 42.4 |
Comparison: The null hypotheses was that the severe TBI group would not differ from the control group in SRT latencies.p-value: <0.001ANOVA
Comparison: The null hypothesis was that the mild TBI group would not differ in age-corrected z-score from that of a control subjects in the large control group.p-value: 0.5ANOVA