Neuropsychological function in a group of patients 25 years after sustaining minor head injuries as children and adolescents

Previous studies suggest that neuropsychological impairment following mild to moderate pediatric head injury may become persistent and interrupt the normal course of intellectual development. In this study 45 subjects were assessed with a standardized neuropsychological test battery 25 years after sustaining mild to moderate head injury as children. Although the group scores in the normal range, significant relations between head injury severity and current neuropsychological function were found. The most important predictor of poor outcome was length of PTA at injury, EEG pathology, and loss of consciousness at injury. No significant influence of pre- and post-injury risk factors on current neuropsychological function was evident. The findings support the view that complicated mild and moderate paediatric head injury may heighten the risk of developing subtle neuropsychological problems later in life.     

Components of analogical reasoning in a mildly head injured population

This study sought to investigate the effects of mild head injury on a particular type of cognitive ability, verbal analogical reasoning. The performance of 19 individuals with head injuries was compared to a group of 30 control subjects matched for age, education, and gender on 100 verbal analogies. Solution times and error rates were modeled. Unstandardized regression weights for individual subjects were correlated with subjects’ performance on a number of standardized ability tests. Results showed that compared to the control subjects, the head injured subjects: (a) were significantly slower to solve the analogies, and were particularly slow to perform certain processes: encoding/inference and comparison; (b) tended to show greater variability in performance; and (c) had data that had a poorer componential model fit. The data suggest that analogical reasoning is affected by a head injury, and that certain information processes may be responsible for performance deficits.     

Verb retrieval in brain-damaged subjects: 2. Analysis of errors

Verb retrieval for action naming was assessed in 53 brain-damaged subjects by administering a standardized test with 100 items. In a companion paper (Kemmerer & Tranel, 2000), it was shown that impaired and unimpaired subjects did not differ as groups in their sensitivity to a variety of stimulus, lexical, and conceptual factors relevant to the test. For this reason, the main goal of the present study was to determine whether the two groups of subjects manifested theoretically interesting differences in the kinds of errors that they made. All of the subjects' errors were classified according to an error coding system that contains 27 distinct types of errors belonging to five broad categories-verbs, phrases, nouns, adpositional words, and "other" responses. Errors involving the production of verbs that are semantically related to the target were especially prevalent for the unimpaired group, which is similar to the performance of normal control subjects. By contrast, the impaired group had a significantly smaller proportion of errors in the verb category and a significantly larger proportion of errors in each of the nonverb categories. This relationship between error rate and error type is consistent with previous research on both object and action naming errors, and it suggests that subjects with only mild damage to putative lexical systems retain an appreciation of most of the semantic, phonological, and grammatical category features of words, whereas subjects with more severe damage retain a much smaller set of features. At the level of individual subjects, a wide range of "predominant error types" were found, especially among the impaired subjects, which may reflect either different action naming strategies or perhaps different patterns of preservation and impairment of various lexical components. Overall, this study provides a novel addition to the existing literature on the analysis of naming errors made by brain-damaged subjects. Not only does the study advance our knowledge of the relatively under investigated topic of action naming errors, but it also approaches the analysis from the point of view of a detailed, theoretically motivated, and reliable error coding system.     

Assessment of performance validity in the Stroop Color and Word Test in mild traumatic brain injury patients: A criterion‐groups validation design

The current study assessed performance validity on the Stroop Color and Word Test (Stroop) in mild traumatic brain injury (TBI) using criterion‐groups validation. The sample consisted of 77 patients with a reported history of mild TBI. Data from 42 moderate–severe TBI and 75 non‐head‐injured patients with other clinical diagnoses were also examined. TBI patients were categorized on the basis of Slick, Sherman, and Iverson (1999) criteria for malingered neurocognitive dysfunction (MND). Classification accuracy is reported for three indicators (Word, Color, and Color–Word residual raw scores) from the Stroop across a range of injury severities. With false‐positive rates set at approximately 5%, sensitivity was as high as 29%. The clinical implications of these findings are discussed.     

Social cognition after head injury: sarcasm and theory of mind

Closed head injury (CHI) is associated with communication difficulties in everyday social interactions. Previous work has reported impaired comprehension of sarcasm, using sarcastic remarks where the intended meaning is the opposite of the sincere or literal meaning. Participants with CHI in the present study were assessed using two types of sarcastic items, those with a directly opposite meaning and those with an indirect, non-literal but not directly opposite meaning. The CHI group was differentially poorer at comprehending sarcastic versus sincere remarks, although type of sarcastic materials did not influence performance. Errors involved not only literal interpretations, but also incorrect non-literal interpretations. Theory of mind (mentalising) was also assessed by comparing comprehension of human actions with control physical events. The CHI group was selectively impaired on the mentalising component of this task, and mentalising scores correlated with sarcasm comprehension. The implications of the findings for our understanding of impaired sarcastic comprehension after acquired brain injury are discussed.     

Mild Head Injury in Children and Adolescents

Although mild head injury is the most prevalent type of head injury in children and adolescents, only a relatively small number of studies on this kind of head injury have been reported. This article summarizes a review of studies examining cognitive, academic, and psychosocial outcomes in children who sustained mild head injuries. Despite earlier claims of mild head injury being a "silent epidemic," the studies, which were published from 1970 to 1998, provide no compelling evidence to support this view.     

Reported head injury and sex differences in color naming, color matching, and digit-string matching.

It was hypothesized that the observed sex differences on three speeded tasks could be accounted for in terms of the greater incidence of head injury in men than in women. In two studies of 64 male and 66 female college students significant sex differences were found on digit-string matching and color-matching tasks. When the data from those 39 subjects with reported histories of head injury were eliminated from the analysis or head-injury reports were statistically controlled, significant sex differences remained. Digit-string matching times were significantly correlated with reported head injury in both studies, suggesting that this test is sensitive to residual effects of head injury.     

Knowledge-based inferencing after childhood head injury

Inferencing was studied with a story comprehension task that required inferences to be made from a controlled knowledge base. Despite similar rates of knowledge base acquisition, knowledge base retention, and speeded access to the knowledge base across groups, the 18 children with severe head injury had lower rates of inferencing than the 15 children with mild head injury or the 18 age-matched controls. Results suggest that cognitive functions such as working memory and metacognitive skill that are disrupted by severe head injury may also play a role in some of the text- and discourse-level deficits commonly reported in these children, notably those involving inferencing.     

Flexible attention deployment in threatening contexts: An instructed fear conditioning study

Factors leading humans to shift attention away from danger cues remain poorly understood. Two laboratory experiments reported here show that context interacts with learning experiences to shape attention avoidance of mild danger cues. The first experiment exposed 18 participants to contextual threat of electric shock. Attention allocation to mild danger cues was then assessed with the dot-probe task. Results showed that contextual threat caused subjects to avert attention from danger cues. In the second experiment, 36 participants were conditioned to the same contextual threat used in Experiment 1. These subjects then were randomly assigned to either an experimental group, trained to shift attention toward danger cues, or a placebo group exposed to the same stimuli without the training component. As in Experiment 1, contextual threat again caused attention allocation away from danger in the control group. However, this did not occur in the experimental group. These experiments show that acute contextual threat and learning experiences interact to shape the deployment of attention away from danger cues. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Neuropsychological impairment as a consequence of football (soccer) play and football heading: a preliminary analysis and report on school students (13-16 years).

Footballers run the risk of incurring mild head injury from a variety of sources, including the intentional use of the head to play the ball, known as heading. This paper presents a preliminary exploratory analysis of data collected to examine whether cumulative incidence of mild head injury, or cumulative heading frequency, are related to neuropsychological functioning in male adolescent footballers. In a quasi-experimental cross-sectional design, neuropsychological test scores of school team footballers were compared with those of similarly aged rugby players and noncontact sport players. Cumulative mild head injury incidence was estimated using self-reports, and cumulative heading was estimated using a combination of observation and self-reports. No participants had sustained a head injury within 3 months of testing. There was no relationship between head injury and neuropsychological performance, and there were no decrements in either the footballers or the rugby players in comparison with the noncontact sport players. Within the footballers, cumulative heading did not predict any of the neuropsychological test scores. These findings indicate the absence of neuropsychological impairment arising due to cumulative mild head injury incidence, or cumulative heading. Although these null findings may be reassuring to players, parents, and football organizers, we stress that they are preliminary. Further data is being collected from the same populations to provide more reliable effect estimates.     

Laterality effects in perceived spatial location of hallucination-like voices

Aydin and colleagues reported a reversal of physiological 'right-ear advantage' in a group of right-handed patients with schizophrenia, using an auditory acuity test. In schizophrenia, auditory hallucinations may appear to be spatially located inside or outside the patient's head. Here we show, using virtual acoustic space techniques, that normal right-handed subjects have a right-ear advantage for correctly locating the 'source' of hallucination-like voices as from either inside or outside the head. We propose a model for understanding lateralised, external hallucinations in schizophrenia based upon reversal of normal cortical asymmetry for auditory spatial processing.     

Neuropsychological impairment as a consequence of football (soccer) play and football heading: A preliminary analysis and report on school students (13–16 years)

Footballers run the risk of incurring mild head injury from a variety of sources, including the intentional use of the head to play the ball, known as heading. This paper presents a preliminary exploratory analysis of data collected to examine whether cumulative incidence of mild head injury, or cumulative heading frequency, are related to neuropsychological functioning in male adolescent footballers. In a quasi-experimental cross-sectional design, neuropsychological test scores of school team footballers were compared with those of similarly aged rugby players and noncontact sport players. Cumulative mild head injury incidence was estimated using self-reports, and cumulative heading was estimated using a combination of observation and self-reports. No participants had sustained a head injury within 3 months of testing. There was no relationship between head injury and neuropsychological performance, and there were no decrements in either the footballers or the rugby players in comparison with the noncontact sport players. Within the footballers, cumulative heading did not predict any of the neuropsychological test scores. These findings indicate the absence of neuropsychological impairment arising due to cumulative mild head injury incidence, or cumulative heading. Although these null findings may be reassuring to players, parents, and football organizers, we stress that they are preliminary. Further data is being collected from the same populations to provide more reliable effect estimates.     

Prevalence of traumatic brain injury in an inpatient psychiatric population

This study investigated the prevalence of traumatic brain injury (TBI) in an inpatient psychiatric population. We hypothesized increased prevalence of TBI relative to the general population due to a variety of risk factors observed in psychiatric patients. One hundred (mean age = 34) psychiatric inpatients completed the revised Head Injury Questionnaire. Chart review of 17 subjects reporting injuries established whether injuries were documented in medical records. Sixty-eight percent of this psychiatric population reported one or more injuries in which they were unconscious or dazed. This number is higher than the prevalence in the general population. Injuries were generally of mild to moderate severity; multiple injuries were common. Chart review of 17 subjects reporting TBI indicated that histories of TBI had not been noted in the medical record. Finally, 63% of TBI subjects reported that their injury predated the onset of their psychiatric symptoms. These results suggest a possible role of TBI in psychiatric symptomatology and have implications for psychiatric treatment in this population.     

Attributions of behavior in the pediatric mild closed head injury (CHI) population

Forty-one children between the ages of 6 and 11 years with a history of a mild closed head injury and 23 age-, gender-, and IQ-matched typically developing control children participated. All of the children in the CHI sample were referred for a magnetic resonance imaging (MRI) scan at 3 months post-injury and children in the CHI sample were further divided into MRI-Negative (n=31) and MRI-Positive (n=10) conditions according to the MRI results. Parents and teachers completed behavioral checklists at three points, including just prior to the MRI and 6 months post-injury. Prior to the MRI (Time 2), in both samples of children with a CHI, parents reported an increase in externalizing symptoms after the CHI. At 6 months post-injury (Time 3: post-MRI), parents of children in the MRI-Positive group did not report any significant changes in their child's externalizing behaviors when compared with pre-MRI, yet parents of children in the MRI-Negative group reported a further increase in externalizing behaviors. Parent attributions also changed as a function of group membership; whereas no changes were noted in the other two groups, parents of children in the MRI-Negative sample ascribed more controllability at Time 3 when compared with Time 2.     

Individualized behavior therapy for alcoholics: a third year independent double-blind follow-up.

An independently conducted double-blind study providing third year follow-up data for 53 of 70 male alcoholics who served as subjects in an experiment evaluating “Individualized Behavior Therapy (IBT)” techniques is reported. In the original study, subjects were initially assigned to either a controlled drinking or non-drinking (abstinence) treatment goal, and were then randomly assigned to either an experimental group receiving IBT or a control group receiving conventional state hospital treatment oriented towards abstinence. Previously reported results showed that IBT subjects functioned significantly better than control subjects throughout the first year of follow-up. Second year follow-up results found that IBT subjects treated with a controlled drinking goal functioned significantly better than their respective control subjects on a variety of measures, including drinking behavior. Differences between IBT subjects treated with a non-drinking goal and their control subjects did not retain statistical significance during the second year of follow-up. The independently determined follow-up data showed that during the third post-treatment year, subjects in the experimental groups generally functioned better than their respective control subjects. Comparison of the controlled drinking experimental group with its control group showed the significantly better functioning of subjects in the experimental condition on a number of drinking and other life functioning measures. Comparison of the non-drinking groups indicated only one possible difference on the drinking related measures involving a trend for subjects in the experimental condition to abstain more than those in the non-drinker control group. On other life functioning measures, however, subjects in the non-drinking experimental condition showed consistent improvement over their respective control subjects. Both of the controlled drinking groups reported more controlled drinking days than the non-drinking groups throughout the third year follow-up period.     

Parameters of digitally averaged potentials of individual motor units]

Of sixty normal subjects of different age six different muscles each were examined electromyographically. The activity pattern was recorded for moderate voluntary innervation and superposed digitally. The parameters of digitally averaged summation action potentials were compared with those of manually assessed potentials. The two methods gave identical results: The duration of potentials was between 5 and 10 ms. It increased in the younger and older age groups and showed only slight changes in middle-aged persons. Only minor differences were found between the muscles of one age group, an exception being the orbicularis oris muscle. The results obtained are compared with values reported in the literature.     

Linguistic recovery after closed head injury

Recovery from acute aphasia after closed head injury was studied in 21 young adults at least 6 months after injury. Three profiles of scores were found using standardized language tests. Persistent expressive and receptive impairment was present in 6 patients who sustained severe diffuse brain injury resulting in global cognitive deficit. Residual expressive impairment, primarily of naming, was associated with mild diffuse brain injury though focal left-hemisphere injury was present in 3 of 6 cases. Patients who recovered to normal levels on all language tests generally had acute neurologic findings consistent with mild diffuse brain injury. Cranial computed tomography at the time of followup frequently disclosed ventricular enlargement.     

Cognitive contributions to theory of mind ability in children with a traumatic head injury

The objective of the current study is to examine the contribution of intellectual abilities, executive functions (EF), and facial emotion recognition to difficulties in Theory of Mind (ToM) abilities in children with a traumatic head injury. Israeli children with a traumatic head injury were compared with their non-injured counterparts. Each group included 18 children (12 males) ages 7–13. Measurements included reading the mind in the eyes, facial emotion recognition, reasoning the other’s characteristics based on motive and outcome, Raven’s Coloured Progressive Matrices, similarities and digit span (Wechsler Intelligence Scale for Children – Revised 95 subscales), verbal fluency, and the Behaviour Rating Inventory of Executive Functions. Non-injured children performed significantly better on ToM, abstract reasoning, and EF measures compared with children with a traumatic head injury. However, differences in ToM abilities between the groups were no longer significant after controlling for abstract reasoning, working memory, verbal fluency, or facial emotion recognition. Impaired ToM recognition and reasoning abilities after a head injury may result from other cognitive impairments. In children with mild and moderate head injury, poorer performance on ToM tasks may reflect poorer abstract reasoning, a general tendency to concretize stimuli, working memory and verbal fluency deficits, and difficulties in facial emotion recognition, rather than deficits in the ability to understand the other’s thoughts and emotions. ToM impairments may be secondary to a range of cognitive deficits in determining social outcomes in this population.     

Foreperiod and stuttering severity effects on acoustic laryngeal reaction time

An earlier paper presented a model of the laryngeal reaction time (LRT) paradigm that included several factors that appeared to affect LRT values. The present study assesses the effects of two of these factors: foreperiod and stuttering severity. The former was assessed by the use of 13 foreperiod durations. The latter was assessed by classifying experimental subjects as either mild or severe stutterers. Both factors significantly affected LRT values. More importantly, these factors demonstrated a composite effect on group LRT differences. Specifically, mild stutterers' LRT values approached normal values as foreperiod increased, whereas severe stutterers' LRT values remained significantly greater than normal values at all foreperiods. Results are discussed in terms of differential posturing and/or vibration initiation deficits underlying stutterers' delayed LRT values. We caution that acoustic measurements alone are insufficient to specify fully the nature of the underlying deficits.     

Psychological functioning after severe closed head injury

The residual effects of severe closed head injury on psychological functioning, as determined by data from the Rorschach test, were examined. Thirty-five young adult patients with severe closed head injury were compared to a nonpatient, non-head injured matched group sample of 36 subjects. The utility of the Rorschach test in distinguishing the characteristic psychological functioning of inpatients who have suffered from severe closed head injury was outlined. The apperceptive disturbance, affective/cognitive problems, and interpersonal difficulties were discussed.