Closed Head Injured Patients Research Articles

Identification of hematomas in mild traumatic brain injury using an index of quantitative brain electrical activity.

Rapid identification of traumatic intracranial hematomas following closed head injury represents a significant health care need because of the potentially life-threatening risk they present. This study demonstrates the clinical utility of an index of brain electrical activity used to identify intracranial hematomas in traumatic brain injury (TBI) presenting to the emergency department (ED). Brain electrical activity was recorded from a limited montage located on the forehead of 394 closed head injured patients who were referred for CT scans as part of their standard ED assessment. A total of 116 of these patients were found to be CT positive (CT+), of which 46 patients with traumatic intracranial hematomas (CT+) were identified for study. A total of 278 patients were found to be CT negative (CT-) and were used as controls. CT scans were subjected to quantitative measurements of volume of blood and distance of bleed from recording electrodes by blinded independent experts, implementing a validated method for hematoma measurement. Using an algorithm based on brain electrical activity developed on a large independent cohort of TBI patients and controls (TBI-Index), patients were classified as either positive or negative for structural brain injury. Sensitivity to hematomas was found to be 95.7% (95% CI = 85.2, 99.5), specificity was 43.9% (95% CI = 38.0, 49.9). There was no significant relationship between the TBI-Index and distance of the bleed from recording sites (F = 0.044, p = 0.833), or volume of blood measured F = 0.179, p = 0.674). Results of this study are a validation and extension of previously published retrospective findings in an independent population, and provide evidence that a TBI-Index for structural brain injury is a highly sensitive measure for the detection of potentially life-threatening traumatic intracranial hematomas, and could contribute to the rapid, quantitative evaluation and treatment of such patients.

Comparison Between Three Memory Tests: Cued Recall, Priming and Saving Closed-Head Injured Patients and Controls

Twenty closed-head injured (CHI) patients and 20 matched controls were tested with three different memory tasks: cued recall, word stem completion (WSC), and saving. Saving is defined as the advantage of relearning of a list of word pairs, in terms of the number of learning trials to the criterion of one errorless trial, over the original learning of the same list. It was predicted that CHI patients' explicit memory (i.e., cued recall), but not implicit memory (i.e., WSC), would be impaired. The question addressed in this study is whether the memory of CHI patients will be impaired when memory is tested with a saving task, with 2 weeks delay between original learning and relearning. The findings confirm impairment of CHI patients in explicit memory, although the learning rate is preserved. Implicit memory is preserved in CHI patients only when based on reactivation of preexisting knowledge, but not when dependent on forming new associations. Finally, the CHI patients, even after 2 weeks delay, demonstrated a significant saving in relearning old, as compared to new, pairs of words. The clinical contribution of this study is the delineation of those aspects of memory that are impaired and those that are preserved in CHI patients. The theoretical implications of the finding that memory could be preserved in CHI patients when measured by saving, are discussed in terms of the relationship between implicit memory and saving.

Acquisition of skilled visual search performance following severe closed-head injury.

This study used a semantic-category visual search task to investigate skill acquisition and automatic process development in a severe closed-head injured (CHI) population. Eighteen severe CHI participants (> I year post injury) and 18 matched controls completed over 3600 trials of training in both consistent mapping (CM) and varied mapping (VM) training situations. Transfer conditions were also used to test for development of an automatic attention response (AAR) that was independent of general, task-related learning. For both the severe CHI and control group, CM training, where individuals always responded in the same way to a specific class of stimuli, resulted in dramatic performance improvements and the development of an AAR. In the VM training condition, where individuals could not respond in the same way to a class of stimuli from one stimulus exposure to the next, there was little performance improvement and continued reliance on controlled processes. The visual search rates of the CHI participants also remained slower than those of controls following extended VM but not extended CM practice. These results indicate that skill acquisition training guidelines can be used to teach severe CHI patients to develop a new automatic skill.

The use of cranial electrotherapy stimulation in the management of chronic pain: A review

Cranial Electrotherapy Stimulation (CES) has a growing history of applications in rehabilitation medicine in the United States dating back to early 1970. As a recognized non-drug treatment of anxiety, depression and insomnia, CES gained its first major application in the field of addiction treatment and rehabilitation. By the mid 1980s research was showing additional important uses of CES in the treatment of closed head injured patients, and in paraplegic and quadriplegic patients. The most recent research is showing CES to be highly effective in the management of chronic pain patients. It may be elevating the pain threshold due to its stress reducing effects when anxiety and depression are reduced below clinical levels. Modern theorists of a pain neuromatrix in the cerebral cortex may provide an additional basis for understanding CES mechanisms in the control of pain related disorders.

Naming Famous Faces and Buildings

Reports of a dissociation between impaired retrieval of people's names and spared retrieval of other categories of proper names have led to the suggestion that there are separate brain mechanisms for processing different categories of proper names. An alternative explanation states that geographical proper names (e.g. cities, countries) may be spared in patients with proper name anomia because they are easier to retrieve than people's names. Unlike people's names, geographical names are also used as adjectives. However, this explanation can not explain why retrieval of proper names that are never used as adjectives (e.g. buildings) was spared in some patients. This study investigated whether retrieving people's names is equally difficult as retrieving the names of buildings. Results from normal subjects and closed-head injured patients revealed no differences between retrieval of people's names and buildings' names, and suggested that both categories of proper names are equally vulnerable to brain injury.

Event-related brain potentials reveal covert distractibility in closed head injuries.

Event-related brain potentials (ERPs) to auditory stimuli were recorded from 11 closed head injured (CHI) and 10 age-matched healthy adults. Auditory stimuli consisted of sequences of repetitive standard tones (600 Hz), occasionally replaced by deviant tones (660 Hz) or by natural novel sounds. Subjects were instructed to ignore auditory stimuli while concentrating on a demanding visuo-motor tracking task. CHI patients showed, in comparison to control subjects, significantly enhanced late P3a component in the ERPs to novel sounds. This suggests that novel stimuli cause greater distraction in CHI patients than in controls, demonstrating that ERPs provide a powerful tool to determine the physiological basis of attentional deficits in CHI patients.

Biophysical Linkage between MRI and EEG Coherence in Closed Head Injury

Using conventional MRI procedures, nuclear magnetic resonance (NMR) of brain water proton (1H)T2 relaxation times and EEG coherence were obtained from two independent groups of closed head injured (CHI) patients and a group of normal control subjects. Statistically significant intercorrelations were observed between1HT2 relaxation times of the cortical gray and white matter and EEG coherence. The analyses showed that lengthened1HT2 relaxation times of the cortical gray and white matter were related to: (1) decreased EEG coherence between short interelectrode distances (e.g., 7 cm) and increased EEG coherence between long interelectrode distances (e.g., 28 cm), (2) differences in EEG frequency in whichT2 relaxation time was most strongly related to the gray matter in the delta and theta frequencies in CHI patients, and (3) increasedT2 relaxation time and decreased short-distance EEG coherence were related to reduced cognitive function. The results were interpreted in terms of reduced integrity of protein/lipid neural membranes and the efficiency and effectiveness of short- and long-distance neural synchronization following traumatic brain injury.

Biophysical Linkage between MRI and EEG Amplitude in Closed Head Injury

Nuclear magnetic resonance of brain water proton (1H) T2 relaxation times and measures of absolute amplitude of EEG were obtained from 19 closed head injured patients. The relationship between EEG and T2 relaxation time differed as a function of both EEG frequency and gray matter versus white matter. White matter T2 relaxation time was positively correlated with increased EEG amplitude in the δ frequency band (0.5–3.5 Hz). In contrast, lengthened gray matter T2 relaxation time was inversely correlated with EEG amplitude in the α and β frequency bands (7–22 Hz). These findings are consistent with clinical EEG studies in which white matter lesions are related to increased EEG δ amplitude and gray matter lesions are related to decreased EEG α and β frequency amplitude. Estimates of the severity of injury were obtained by neuropsychological measurements, in which lengthened T2 relaxation times in both the neocortical gray and white matter were correlated with diminished cognitive function. Decreased EEG β and α amplitude and increased EEG δ amplitude were also correlated with diminished cognitive function. The findings imply a biophysical linkage between the state of protein–lipid structures of the brain as measured by the MRI and the scalp-recorded EEG.

Hyperawareness of Neuropsychological Deficits in Patients with Mild Closed Head Injuries: A Preliminary Investigation

This study investigated awareness in mild closed head injured (CHI) patients by comparing patient and significant other ratings on personality and neuropsychological items. Twenty CHI patients, their significant others, and 20 control participants and their significant others completed the DSM-IV aligned, Coolidge Axis II Inventory. The CHI group rated themselves significantly higher than controls on the neuropsychological dysfunction scale indicative, perhaps, not only of an awareness of deficits, but even a kind of hyperawareness of deficits. The CHI group also rated themselves significantly lower than the controls on the emotional control scale. There were no differences between the two groups in their self-ratings or on the significant other ratings on the executive function (EF) deficits, anxiety, depression, or social interactions scales. Overall, CHI patients more often appeared hyperaware of their neuropsychological deficits and emotional limitations than unaware of these deficits. The discussion explores implications of the findings.

The effect of level of processing on perceptual and conceptual priming: Control versus closed-head-injured patients

Twenty-four closed-head-injured (CHI) and 24 control participants studied two word lists under shallow (i.e., nonsemantic) and deep (i.e., semantic) encoding conditions. They were then tested on free recall, perceptual priming (i.e., perceptual partial word identification) and conceptual priming (i.e., category production) tasks. Previous findings have demonstrated that memory in CHI is characterized by inefficient conceptual processing of information. It was thus hypothesized that the CHI participants would perform more poorly than the control participants on the explicit and on the conceptual priming tasks. On these tasks the CHI group was expected to benefit to a lesser degree from prior deep encoding, as compared to controls. The groups were not expected to significantly differ from each other on the perceptual priming task. Prior deep encoding was not expected to improve the perceptual priming performance of either group. All findings were as predicted, with the exception that a significant effect was not found between groups for deep encoding in the conceptual priming task. The results are discussed (1) in terms of their theoretical contribution in further validating the dissociation between perceptual and conceptual priming; and (2) in terms of the contribution in differentiating between amnesic and CHI patients. Conceptual priming is preserved in amnesics but not in CHI patients.

Performance on the Wechsler Memory Scale-Revised for patients with mild traumatic brain injury and mild dementia.

The purpose of this study was to delineate significant differences among mild traumatic brain-injured and early onset mild dementia patients examined using the Wechsler Memory Scale-Revised subtests. In comparison to 12 mild traumatic brain-injured patients, 11 mild dementia patients scored significantly lower on Verbal Paired Associates I and II, Visual Reproduction I and II, and Visual Paired Associates I. Raw score summaries for the Wechsler Memory Scale-Revised indicated significantly lower scores on Verbal Memory, Visual Memory, and the over-all composite. General Memory for mild dementia patients in comparison to individuals who sustained a mild traumatic brain injury. Despite equivalent scores on Attention/Concentration, the dementia group did not show significantly lowered delay in memory recall by comparison with mild closed-head injured patients. The study recommends replication with much larger sample sizes to validate the results.

Four-year follow-up of a controlled memory training study in closed head injured patients

Abstract In a controlled group study Berg, Koning-Haanstra, and Deelman (1991) compared the effects of memory strategy training with the effects of drill and practice training and no treatment in severely head injured patients. Four months after training the group in the strategy condition performed significantly better on three memory tests than the patient groups in the other two conditions. Four years following this last evaluation, 31 of the 38 patients from the original training study were retested on the same memory tests. Thirteen normal subjects, who had already served as normal controls in the training study, were also retested. In contrast to the results four years earlier, memory performance was the same for all three patient groups. The level of performance of the patients was still well below the level of the normal controls. One reason for the disappearance of the advantage of the strategy group over the other two patient groups, was the drop-out of patients with relatively poor memory scores on the previous evaluation. A second reason was the improvement in memory performance relative to the previous evaluation found in the drill and practice and the no-treatment groups.

Stroop color-word task as a measure of selective attention: efficiency in closed-head-injured patients.

Deficits in attention and concentration are reported to be among the most common symptoms following head injury. Various underlying mechanisms of selective attention such as excitation, inhibition, and habituation have been isolated in recent studies. In the present study 27 control and 25 closed-head-injured (CHI) subjects were compared on four conditions based on the Stroop color-word task (neutral, habituation, Stroop, and negative priming). Cross-comparison of the different tasks enables examination of the various components of selective attention. The hypothesis that the control group's overall reading time would be faster than that of the CHI group was confirmed. Also confirmed was the hypothesis that the overall reading time pattern between task conditions would be neutral < habituation < Stroop < negative priming. The prediction that the CHI patients, due to their impaired inhibitory mechanism, would not show a slower reading time on the negative priming as compared to the Stroop condition, was confirmed as well. The theoretical and diagnostic implications of the results are discussed.

Long-term vocational functioning after severe closed head injury: A controlled study

Vocational functioning at least 2 years postinjury was examined in a group of 57 severely closed-head injured (CHI) patients and 50 nonbrain-injured spinal-cord injured (SCI) patients. The two groups were equated on the following preinjury parameters: age, education, socioeconomic status (SES), male/female ratio, and marital status. The CHI and SCI patients had a similar number of members who were employed at follow-up. However, mean follow-up socioeconomic status was significantly lower in the CHI group and premorbidly employed CHI patients suffered a greater loss of SES than did premorbidly employed SCI patients. These results indicate that the degree of vocational impairment after severe CHI goes beyond impairment seen with another chronic disabling condition (i.e., SCI) that is associated with severe physical impairment but not neuropsychological impairment. In the CHI group, the following variables were all correlated with SES at follow-up: preinjury education, posttraumatic amnesia duration, degree of neuropsychological impairment soon after injury, and emotional adjustment at follow-up.

Relative importance of informational units and their role in long-term recall by closed-head-injured patients and control groups.

The purpose of this study was to apply qualitative analysis to the information recalled by control Ss and closed-head-injured (CHI) patients. The Logical Memory subtest of the Wechsler Memory Scale (Wechsler, 1945) was administered to 40 CHI and 40 control Ss. Recall was tested immediately after administration, 40 min later, and 24 hr later. The analysis took into account the importance of recalled information as determined by a prior rating according to 3 levels of importance. Results suggest that CHI patients have difficulty selectively retrieving the most important information after a long delay.

Effects of closed-head injury on attentional processes: An information-processing stage analysis

The present study, based on Sternberg's (1969) additive-factor method, examined attentional processes in terms of four information-processing stages (feature extraction, identification, response selection, and motor adjustment). Four task variables were used to operationally define the stages (signal quality, signal similarity, signal-response compatibility, and foreperiod uncertainty). In two studies, a visuo-spatial reaction-time task was undertaken by a group of university subjects (Experiment 1) and by three groups of closed-head-injured patients (severe short-term, severe long-term, and mild short-term) and their corresponding matched controls (Experiment 2). The results indicated that both patients and normals exhibited a similar mode of linear information processing. In addition, it was found that the severe short-term group was impaired on the response-selection stage and response selection stage; the severe long-term group was impaired only on the response-selection; and no evidence of impairment was found for the mild short-term patients. The implications of these findings with reference to the study of attentional processes in closed-head injured patients and to neuropsychological assessment and rehabilitation are discussed.

Recovery of memory after severe closed head injury: dissociations in recovery of memory parameters and predictors of outcome.

This study examined selective reminding and recognition memory performance of 21 severe closed-head injured patients tested within 6 months of regaining consciousness and then again after at least 1 year. Performances on selective reminding parameters were highly correlated and patients performed significantly worse at both testings than did hospitalized controls matched for age, education, and sex. Patients improved from testing 1 to testing 2 on only four of six memory variables. Average Impairment Rating at testing 1 was a marginally better predictor of memory performance at testing 2 than was length of coma. Results are discussed in terms of (a) utility of selective reminding parameters and predictors of outcome and (b) dissociations in recovery of memory parameters.

Local cerebral glucose abnormalities in mild closed head injured patients with cognitive impairments.

Mild-moderate closed head injury (CHI) can be followed by neuropsychological impairments in recent memory and attention, despite the absence of discernible structural abnormalities in a significant number of patients. To determine whether CHI may result in cerebral glucose metabolic abnormalities, we used fluorodeoxyglucose (FDG) technique with PET imaging to measure local cerebral metabolic rates for glucose (LCMRGlu) in three CHI patients and three matched normal controls. The CHI patients were between 3-12 months post-injury. All had deficits in attention and recent memory shown by neuropsychological testing. CT, MRI, EEG and drug screens were negative at the time of PET scanning. Subjects were engaged in a vigilance task throughout the initial 30 min following FDG administration. Group comparisons were made using t tests. There were no significant group differences found in global glucose metabolic rate. Nevertheless, the CHI group exhibited significantly decreased LCMRGLu in medial temporal, posterior temporal, and posterior frontal cortices, as well as in the left caudate nucleus. LCMRGlu was significantly increased, relative to controls, in anterior temporal and anterior frontal cortices. These results suggest that CHI patients can have regional glucose metabolic abnormalities, indicative of altered neuronal function, despite the absence of discernible anatomic abnormalities.

The efficacy of cognitive rehabilitation with mildly closed head injured patients with premorbid high achievement functioning

Journal Article The efficacy of cognitive rehabilitation with mildly closed head injured patients with premorbid high achievement functioning Get access L. Derr, L. Derr Neuropsychological Services of Virginia, Inc. Search for other works by this author on: Oxford Academic PubMed Google Scholar E. Peck E. Peck Neuropsychological Services of Virginia, Inc. Search for other works by this author on: Oxford Academic PubMed Google Scholar Archives of Clinical Neuropsychology, Volume 4, Issue 2, 1989, Page 141, https://doi.org/10.1093/arclin/4.2.141 Published: 01 April 1989

The efficacy of cognitive rehabilitation with mildly closed head injured patients with premorbid high achievement functioning

The efficacy of cognitive rehabilitation with mildly closed head injured patients with premorbid high achievement functioning