Attentional deficits in head-injured children: an information processing analysis

Evolution of the cognitive profile in school-aged patients with severe TBI during the first 2 years of neurorehabilitation

OBJECTIVE

Persistent post-injury cognitive, academic and behavioural deficits have been documented in children who sustained severe TBI during the school-age years. The major aim of this study was to examine and follow-up for 2 years the cognitive profile of a sample of post-injured patients (aged 6-16.11), in order to verify to what extent they recovered their intellectual functions after rehabilitation.

METHOD

Twenty-six patients who received a specific neuropsychological treatment and three cognitive evaluations with WISC-III were selected from a pool of 77.

RESULTS

This group of patients showed a mild cognitive deficit at baseline, which improved over the 2 years to a borderline level. Despite the improvement in intellectual quotients and single sub-test scores achieved through rehabilitation, different recovery times were seen according to the function under study. The most common deficits are in processing speed, inferential and lexical-semantic skills.

CONCLUSIONS

Detailed analysis of the WISC-III sub-tests allows for an accurate description of single cognitive functions after TBI. This allows one to make differential diagnoses between functional profiles and plan individualized rehabilitation treatments. Post-injured school-aged patients should receive rehabilitation for a period of at least 2 years, which is the time necessary for an at-least partial reorganization of basic cognitive functions.

Cognitive and adaptive functioning after severe TBI in school-aged children

OBJECTIVE

Persistent cognitive and behavioural deficits have been documented in children suffering severe TBI. The aim of the present study was to examine the cognitive and adaptive profile of children of school age with severe TBI.

METHODS

This study selected 118 patients and divided them into three groups according to the severity of their clinical-functional picture. All the patients received a functional assessment using the Wee-FIM. Subjects with reduced responsiveness were evaluated by LOCFAS. Last, the cognitive profile children with a better recovery were described with WISC-III and Leiter-R and their adaptive behaviour with VABS.

RESULTS

Group 1 (n = 77) showed a borderline cognitive level with a disharmonious profile between VIQ and PIQ, significant deficits in the Processing Speed and Perceptual Organization Indices, lastly specific adaptive behavioural deficits. Length of coma correlated with their cognitive and adaptive profile. Group 2 (n = 14) included subjects with severe language and/or motor disabilities presenting with a partial cognitive functioning level moderately impaired. Group 3 (n = 27) included patients with reduced responsiveness (LOCFAS ≤ 3).

CONCLUSIONS

In the first 12 months following severe TBI, 22.9% children stayed in minimal responsiveness, 11.9% showed debilitating language and motor deficits and 65.2% showed a more favourable cognitive recovery and could be assessed by WISC-III.

Mathematical outcomes and working memory in children with TBI and orthopedic injury

This study compared mathematical outcomes in children with predominantly moderate to severe traumatic brain injury (TBI; n550) or orthopedic injury (OI; n547) at 2 and 24 months post-injury. Working memory and its contribution to math outcomes at 24 months post-injury was also examined. Participants were administered an experimental cognitive addition task and standardized measures of calculation, math fluency, and applied problems; as well as experimental measures of verbal and visual-spatial working memory. Although children with TBI did not have deficits in foundational math fact retrieval, they performed more poorly than OIs on standardized measures of math. In the TBI group, performance on standardized measures was predicted by age at injury, socioeconomic status, and the duration of impaired consciousness. Children with TBI showed impairments on verbal, but not visual working memory relative to children with OI. Verbal working memory mediated group differences on math calculations and applied problems at 24 months post-injury. Children with TBI have difficulties in mathematics, but do not have deficits in math fact retrieval, a signature deficit of math disabilities. Results are discussed with reference to models of mathematical cognition and disability and the role of working memory in math learning and performance for children with TBI.

Early attention impairment and recovery profiles after childhood traumatic brain injury

OBJECTIVES

To examine recovery of attention from 3 to 6 months postinjury; to identify effects of injury severity and time since injury on performance; to explore whether complex attention skills (eg, shifting, divided attention, attentional control) are more vulnerable to traumatic brain injury (TBI), and slower to recover than simple attention skills (eg, attentional capacity, selective attention, sustained attention).

DESIGN

Prospective longitudinal investigation.

PARTICIPANTS

A total of 205 school-aged children with TBI were divided into groups according to injury severity (mild = 63%, moderate = 27%, severe = 10%).

SETTING

Emergency departments of 3 metropolitan children's hospitals across Australia.

MAIN MEASURES

Standardized clinical measures of both simple and complex attention were administered at 3 months and 6 months postinjury.

RESULTS

Attention skills were vulnerable to the impact of TBI. More severe injury affected attention skills most negatively. Significant recovery was observed over time. There were few interaction effects, with severity groups exhibiting similar levels of recovery over the 6 months post-TBI. No differences in recovery trajectories were detected for simple and complex attention.

CONCLUSIONS

These findings have important clinical and educational implications, suggesting that children with TBI, and particularly those with more serious injuries, are most vulnerable to attention deficits in the acute stages postinjury. It is important that schools and families are aware of these limitations and structure expectations accordingly. For example, gradual return to school should be considered, and in the early stages of recovery, children should be provided with sufficient rest time, with reduced expectations for tasks such as homework.

Stimulant Use in Paediatric Acquired: Brain Injury: Evaluation of a Protocol

Children with acquired brain injury (ABI) experience deficits in attentional skills such as, sustained attention, distractability and impulsivity, which have the potential to influence all aspects of their functioning. The use of central nervous system (CNS) stimulants is gaining increasing popularity in adult ABI literature. CNS stimulants have been successfully utilised in the management of attentional problems in attention deficit-hyperactivity disorder and are believed to have their therapeutic effect by modulating neurotransmitter function in the neocortex, an area of the brain implicated in the neurobehavioural sequelae of ABI. Research into the use of CNS stimulants in paediatric ABI reports contradictory findings. We present the case of LI a 7-year-old boy with a history of ABI who underwent a trial of stimulant medication for management of attentional deficits. The case is discussed with regard to the efficacy of the pharmacological intervention and the design of objective protocols for stimulant trials.

Attention processing abnormalities in children with traumatic brain injury and attention-deficit/hyperactivity disorder: differential impairment of component processes

Individuals with acquired and neurodevelopmental brain disorders often exhibit deficits in attention. Recent models of attention have conceptualized it as a multicomponent system. One influential model proposed by Mirsky et al. (1991) consists of factors that include focus, sustain, shift, and encode components. This model has been used to examine the structure of attention in a variety of clinical populations although few studies have contrasted performance of various clinical groups in order to determine whether these components are differentially affected. To address this issue, the current study investigated the differential sensitivity of these attention components in 90 children: 30 who had sustained traumatic brain injury (TBI), 30 who were diagnosed with attention-deficit/hyperactivity disorder (ADHD), and 30 normal controls. Results demonstrated that the TBI group had significantly lower focus factor scores, the ADHD group had significantly lower sustain scores, and that both clinical groups had lower encode factor scores than controls. Stepwise discriminant function analysis (DFA) retained the focus and encode factors in predicting clinical groups from controls with 75.6% accuracy. A second DFA retained the focus factor in differentiating the two clinical groups with 70.0% accuracy. These findings provide evidence of differential attention deficits resulting from TBI and ADHD.

Theory of mind in children with traumatic brain injury

OBJECTIVE

This study was designed to examine the existence of deficits in mentalizing or theory of mind (ToM) in children with traumatic brain injury (TBI).

RESEARCH DESIGN

ToM functioning was assessed in 12 children aged 6-12 years with TBI and documented frontal lobe damage and compared to 12 controls matched for age, sex and verbal ability. Brief measures of attention and memory were also included.

MAIN OUTCOME AND RESULTS

The TBI group was significantly impaired relative to controls on the advanced ToM measure and a measure of basic emotion recognition. No difference was found in a basic measure of ToM.

CONCLUSION

Traumatic brain damage in childhood may disrupt the developmental acquisition of emotion recognition and advanced ToM skills. The clinical and theoretical importance of these findings is discussed and the implications for the assessment and treatment of children who have experienced TBI are outlined.

Sustained attention in children and adolescents after traumatic brain injury: relation to severity of injury, adaptive functioning, ADHD and social background

PRIMARY OBJECTIVE

To examine the relationship of child and family psychosocial variables and traumatic brain injury (TBI) severity as it relates to sustained attention (the Paediatric Assessment of Cognitive Efficiency, PACE).

RESEARCH DESIGN

Forty-two children and adolescents were recruited and participated in a 2 year longitudinal study to evaluate sustained attention using the computerized testing metric, PACE. More specifically, errors of omission (inattention) and commission (impulsiveness) were measured.

MAIN OUTCOMES AND RESULTS

Significant improvement on inattention and impulsiveness were observed over time. High pre-injury psychosocial adversity and low pre-injury adaptive functioning significantly predicted a greater number of inattention errors. Severity of injury predicted the reduction of impulsiveness. Moreover, omission errors immediately after TBI predicted later secondary attention-deficit/hyperactivity disorder (SADHD, ADHD that emerges after TBI).

CONCLUSIONS

Based on these findings, it is important to consider pre-injury child and family psychosocial characteristics in addition to severity of injury when predicting outcome of TBI in children.

Do lesion site and severity predict deficits in attentional control after preschool traumatic brain injury (TBI)?

PRIMARY OBJECTIVE

To determine the predictive value of structural neuroimaging in the clinical setting following TBI.

RESEARCH DESIGN

Prospective between-group design, comparing groups with regard to: (i) the presence or absence of cerebral pathology and (ii) the location of cerebral pathology. The predictive value of injury variables was investigated using hierarchical regressions.

METHODS AND PROCEDURES

Thirty-six children, between 6 and 14 years, who sustained a moderate to severe TBI 5 years previously participated in this study. Children's performances on five measures of attentional control were examined in relation to the presence, location and severity of their lesions, as coded by the Coffey classification system 1.

MAIN OUTCOMES AND RESULTS

Frontal lesion severity was not predictive of performance on any of the measures. However, generalized (frontal and extrafrontal) and extrafrontal lesion severity was predictive of poor performance.

CONCLUSIONS

These findings support the argument that functional organization in children may differ from that in adults, suggesting that multiple cerebral regions, or a diffuse cerebral network, may mediate children's executive functions (EF). Results are also consistent with the hypothesis that the amount of damaged brain tissue, rather than its location, may be more predictive of neurobehavioural outcome following early TBI.

The effects of a midbrain glioma on memory and other functions: a longitudinal single case study

Our understanding of the effects of midbrain damage on cognition is largely based on animal studies, though there have been occasional investigations of the effects of human midbrain lesions on cognition. This investigation of a rare case of a glioma initially confined to the dorsal midbrain explores the effects of disease progression on IQ, memory, and choice reaction time. Extensive dorsal midbrain damage did not appear to affect IQ and various memory functions (including span, working memory, story recall, and remote memory). Choice reaction time latencies increased, while verbal and spatial learning and long-term memory deteriorated with tumour growth, but it was not clear how far the deterioration reflected midbrain damage or damage outside the midbrain.

Traumatic injury to the immature brain results in progressive neuronal loss, hyperactivity and delayed cognitive impairments

The immature brain may be particularly vulnerable to injury during critical periods of development. To address the biologic basis for this vulnerability, mice were subjected to traumatic brain injury at postnatal day 21, a time point that approximates that of the toddler-aged child. After motor and cognitive testing at either 2 weeks (juveniles) or 3 months (adults) after injury, animals were euthanized and the brains prepared for quantitative histologic assessment. Brain-injured mice exhibited hyperactivity and age-dependent anxiolysis. Cortical lesion volume and subcortical neuronal loss were greater in brain-injured adults than in juveniles. Importantly, cognitive decline was delayed in onset and coincided with loss of neurons in the hippocampus. Our findings demonstrate that trauma to the developing brain results in a prolonged period of pathogenesis in both cortical and subcortical structures. Behavioral changes are a likely consequence of regional-specific neuronal degeneration.

The Use of Serum Biomarkers to Predict Outcome After Traumatic Brain Injury in Adults and Children

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality in adults and children. Predicting outcome after TBI is difficult, but it is important for acute management, counseling of family members, and provision of rehabilitation services. Serum biomarkers may be useful alone or in combination with clinical variables to predict outcome after TBI. This article reviews the potential uses of serum biomarkers for the clinician, current literature related to the use of serum biomarkers for outcome prediction after adult and pediatric TBI, limitations of the literature, and future direction for this field.

Understanding predictors of functional recovery and outcome 30 months following early childhood head injury

Much is known about outcome following traumatic brain injury (TBI) in school-age children; however, recovery in early childhood is less well understood. Some argue that such injuries should lead to good outcome, because of the plasticity of the developing brain. Other purport that the young brain is vulnerable, with injury likely to result in a substantial impairment (H. G. Taylor & J. Alden, 1997). The aim of this study was to examine outcomes following TBI during early childhood, to plot recovery over the 30 months postinjury, and to identify predictors of outcome. The study compared 3 groups of children sustaining mild, moderate, and severe TBI, ages 2.0 to 6.11 years at injury, with healthy controls. Groups were comparable for preinjury adaptive and behavioral function, psychosocial characteristics, age, and gender. Results suggested a strong association between injury severity and outcomes across all domains. Further, 30-month outcome was predicted by injury severity, family factors, and preinjury levels of child function. In conclusion, children with more severe injuries and lower preinjury adaptive abilities, and whose families are coping poorly, are at greatest risk of long-term impairment in day-to-day skills, even several years postinjury.

Visuomotor response time in children with a mild traumatic brain injury

OBJECTIVE

Compare the visuomotor response times of children after a mild traumatic brain injury (mTBI) with those of noninjured children matched for age, sex, and premorbid level of physical activity.

DESIGN

Prospective cohort study.

SETTING

Pediatric trauma center.

PARTICIPANTS

Thirty-eight children aged 7 to 16 years in each group. Children with mTBI had a mean Glasgow Coma Scale score of 14.8 and were considered normal on a neurological assessment carried out at the time of hospital discharge. Noninjured children were friends of those with mTBI.

INTERVENTION

Assessments of response time were conducted at 1, 4, and 12 weeks after mTBI and at corresponding time intervals for the control children.

MAIN OUTCOME MEASURES

The response speed subtest of the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP); reaction and movement time for upper and lower extremities, for simple, choice, and reversed choice response time paradigms.

RESULTS

Over the assessment period, children with mTBI performed worse than the control group only on the response speed subtest of the BOTMP. The mTBI children however tended to have slower movement times 1 week postinjury for the reversed choice response time paradigm for the lower extremities.

CONCLUSIONS

Some children with mTBI may have some problems in response time persisting until 12 weeks postinjury. Further research is required to better identify and understand the severity of these problems and determine their impact, if any, on participation in physical activities.

A prospective study of the recovery of attention from acute to 2 years following pediatric traumatic brain injury

Limited research has investigated specific attentional sequelae following pediatric traumatic brain injury (TBI), such as sustained, selective, and shifting attention, as well as speed of processing. Little is known about the pattern of recovery of these skills or their interaction with ongoing development. The present study examined attentional abilities at acute, 6-, 12-, and 24-month time points postinjury in a group of 71 children who had sustained a mild, moderate, or severe TBI. Results indicated that children who sustained a severe TBI generally performed poorest, but showed most recovery over time. The pattern of recovery was dependent on the attentional component being measured. Specifically, deficits were most evident on more complex and timed tasks. While a number of areas showed recovery over time, for some attentional components, difficulties persisted to 24 months postinjury.

Children's attentional skills 2 years post-traumatic brain injury

This study examined sustained attention abilities 24 months postinjury, in 3 groups of children who had suffered a traumatic brain injury (TBI): (a). mild TBI (n = 24), (b). moderate TBI (n = 31), and (c). severe TBI (n = 14). Three manipulations of the traditional Continuous Performance Test paradigm (CPT) were employed in the study, to delineate factors that might influence CPT performance, including speed of processing, attentional lapses, and stimulus complexity. No significant differences were evident among the TBI groups on a measure of simple reaction time, nor on a CPT version where the interstimulus interval was lengthened. However, there was a significant difference between the mild and severe TBI groups on the most complex task, which required speed, accuracy, and decision making, suggesting that these factors underlie impaired performances previously identified on the CPT in children with severe TBI. These findings have implications for the development of intervention programs for these children.

The effect of severe traumatic brain injury on the family

BACKGROUND

The effects of traumatic brain injury on family dynamics and finances have not been extensively studied. We designed a 30-item survey to determine the effects of the injury on the child, parent(s), and siblings, and whether parents were retrospectively content with the decisions related to aggressiveness of care.

METHODS

A questionnaire written on a sixth-grade reading level was mailed to 46 families of children who survived a traumatic brain injury resulting in an initial Glasgow Coma Scale score < or = 7. This is a descriptive study without statistical analysis. Human Studies Committee review and informed consent were obtained.

RESULTS

Thirty-two of 46 (69.6%) surveys were completed by mail or telephone. Mean patient age at time of injury was 8.7 years, mean time since injury was 3 years, and mean Glasgow Coma Scale score was 3.7. Approximately one third of children have disabilities related to education, socialization, and/or self-care skills; require multiple health care visits each month; and require prescription medications. Over one third of families were impacted in a moderate to profoundly negative way; 30% of families reported a deterioration in finances or loss of job; and 16% reported a worsening of adult relationships. In 13 of 32 cases, modification of current housing or new housing was required to facilitate home care. Siblings were adversely affected in approximately 16 of 28 families, exhibiting behavioral problems, increased fear, and withdrawal from the injured child. Only 1 of 32 families stated that they would have considered less aggressive treatment, even if it led to the child's death.

CONCLUSION

Traumatic brain injury of a child had a negative impact on family dynamics and/or sibling behavior in more than one third of families. Despite this, most families would not limit or withdraw care if they could reconsider decisions regarding treatment. This information can be used to counsel families.

Outcome of children with traumatic brain injury in rural Malaysia

Malaysia had the second highest crude accident rate in the world until 1998. Most children who were involved in these road traffic accidents required intensive neurosurgical care management. We report a prospective study on 36 paediatric neurotrauma patients in rural North East West Malaysia who underwent uniform intensive therapy and were subsequently followed up over a period of 2 years. The modified paediatric Glasgow Coma Scale with support of the revised Wechlser Intelligence Scale for children was used to test the outcome of these children over a period of two years. All patients were managed aggressively in our intensive care as well as our high dependency units. Our results indicate that improvement in outcome is seen after a six month period. Midline shift, duration of coma and duration of transport were found to be significant variables associated with bad outcome. Other variables i.e. age, sex, Glasgow Coma Scale on admission and on site, and lesions of the dominant lobe were not found to be associated with good outcome in these patients.

Attention following pediatric head injury: a developmental perspective

This study investigated the relations between age at injury (AAI) and attentional functioning, and intellectual and academic achievement following pediatric head injury. The theoretical framework of attention proposed by Mirsky, Anthony, Duncan, Ahern, and Kellam (1991) provided the basis for this analysis, and the profile of attention found in uninjured children was evaluated for this sample. Thirty-three moderately head-injured individuals were recruited, with AAI ranging from 1 to 12 years. First, the development of attentional skills in this closed head injury (CHI) sample was found to be comparable to that of Mirsky et al.'s model. Second, AAI did not predict outcome and appeared not to be associated with the finding of mildly delayed acquisition of spelling and arithmetic skills. Also, AAI did not predict the behavioral symptoms of inattention present in this sample as indicated by parental report. It may be that AAI only influences development following severe CHI in which there is permanent cerebral pathology.

Inhibitory control in children with traumatic brain injury (TBI) and children with attention deficit/hyperactivity disorder (ADHD)

The behavioural and cognitive sequelae of traumatic brain injury (TBI) have features in common with attention deficit/hyperactivity disorder (ADHD), best characterized by deficits in response inhibition.The performance was, therefore, examined of 27 children with TBI, 31 children with developmental ADHD, and 26 matched controls aged 8-12, on two inhibition tasks: the Stop-Signal Task and a Delayed-Response-Task. Children with TBI and children with ADHD showed a pervasive deficit in their inhibitory control processes with respect to inhibition of both pre-potent and on-going responses. In addition, children with TBI were found to suffer from a general slowing of their information processing, which was not correlated with the inhibition deficit. TBI children with and without a secondary ADHD differed only tendentially in their Mean Go-Reaction time in the stop-task. However, subdividing TBI children according to actigraph data into hypo-, hyper- and normokinetic subgroups revealed that the hyperactive TBI children had inhibitory deficit patterns that were similar to children with developmental ADHD. It is concluded that slowing of information processing speed seems to be a general consequence of TBI in childhood, whereas slowing of the stop-processes or inhibitory deficits, specifically, are associated with post-injury hypo- or hyperactivity.

Recovery of memory function following traumatic brain injury in pre-school children

Traumatic brain injury (TBI) may have a profound impact on a child's ongoing development. Various risk factors have been found to predict outcome, but considerable variability remains unexplained. This study used a prospective, longitudinal design to examine recovery of memory function following TBI within the pre school period. Ninety-six children with TBI were divided according to injury severity (mild, moderate, severe), and compared to age and SES matched healthy controls (n = 35). Children were evaluated acutely and at 6,12 and 18 months post-injury using intellectual and memory measures. Results showed a relationship between greater injury severity and poorer intellectual ability. This dose-response relationship was not clearly evident for memory function within the acute phase of recovery, but developed over time, with greater memory impairments evident for children with more severe TBI by 12 months post-injury. Children with mild TBI exhibited few memory problems. Findings are discussed in the context of theories of plasticity and recovery of function.

Long-term dysfunction following diffuse traumatic brain injury in the immature rat

Children often suffer sustained cognitive dysfunction after severe diffuse traumatic brain injury (TBI). To study the effects of diffuse injury in the immature brain, we developed a model of severe diffuse impact (DI) acceleration TBI in immature rats and previously described the early motor and cognitive dysfunction posttrauma. In the present study, we investigated the long-term functional ability after DI (150 gm/2 m) compared to sham in the immature (PND 17) rat. Beam balance and inclined plane latencies were measured daily for 10 days after injury to assess gross vestibulomotor function. The Morris water maze (MWM) paradigm was evaluated monthly up to 3 months after DI and sham injuries. Reduced latencies on the balance beam and inclined plane were observed in DI rats (p < 0.05 vs. sham [n = 10 per group]) at 24 h and persisted for 10 days postinjury. DI produced sustained MWM performance deficits (p < 0.05 vs. sham) as indicated by the greater latencies to find the hidden platform remarkably through 90 days after injury. Lastly, the brain and body weights of the injured animals were less than sham (p < 0.05) after 3 months. We conclude that a diffuse TBI in the immature rat: (a) created a consistent, marked, but reversible motor deficit up to 10 days following injury; (b) produced a long-term, sustained performance deficit in the MWM up to 3 months posttrauma; and (c) affected body and brain weight gain in the developing rat through 3 months after injury. This TBI model should be useful for the testing of novel therapies and their effect on long-term outcome and development in the immature rat.

Attentional skills following traumatic brain injury in childhood: a componential analysis

Recent research has documented residual deficits in attention following traumatic brain injury in childhood. The present study aimed to investigate whether such deficits are global, or affect specific components of attention differentially. Four attentional domains were examined using a newly developed test of attention, the Test of Everyday Attention for Children: sustained attention, focussed attention, divided attention, and response inhibition. Eighteen children with a history of traumatic brain injury, aged between 8 and 14 years, and 18 non-injured matched controls participated in the study. Results indicated that attentional skills may be differentially impaired after TBI, with children who have sustained moderate-to-severe TBI exhibiting significant deficits for sustained and divided attention, and response inhibition, but relatively intact focussed attention.

Automated visual field examination in children aged 5-8 years. Part I: Experimental validation of a testing procedure

In 106 children aged 5-8 years, we determined how much training was needed to stabilize the response strategy prior to actual visual field assessment and we evaluated the reliability and acceptable duration of automated static perimetry (Octopus 2000R). A specially designed familiarization procedure was used to train the children to: (1) gaze at the center of the visual field while paying attention to light stimuli projected onto the periphery and (2) press the buzzer only when light stimuli were perceived. The subsequent examination phase consisted of 15 successive identical blocks of 27 trials (12 stimulus trials, 12 false-positive catch-trials, and three false-negative catch-trials), and was stopped before the end if signs of fatigue appeared. Age had a marked influence both on endurance (the number of blocks performed increased significantly) and on response reliability (false-positive responses decreased between 5- and 6-year-olds). The increase in false-negative responses toward the end indicates that examination is no longer reliable, and should be stopped. We concluded that most children as young as five can undergo examination by automated static perimetry. Changes regarding learning, stimulus intensity and testing procedure are suggested in order to adapt the examination to age, level of vigilance and health condition of the children.

How children with head injury represent real and deceptive emotion in short narratives

Narratives are not only about events, but also about the emotions those events elicit. Understanding a narrative involves not just the affective valence of implied emotional states, but the formation of an explicit mental representation of those states. In turn, this representation provides a mechanism that particularizes emotion and modulates its display, which then allows emotional expression to be modified according to particular contexts. This includes understanding that a character may feel an emotion but inhibit its display or even express a deceptive emotion. We studied how 59 school-aged children with head injury and 87 normally-developing age-matched controls understand real and deceptive emotions in brief narratives. Children with head injury showed less sensitivity than controls to how emotions are expressed in narratives. While they understood the real emotions in the text, and could recall what provoked the emotion and the reason for concealing it, they were less able than controls to identify deceptive emotions. Within the head injury group, factors such as an earlier age at head injury and frontal lobe contusions were associated with poor understanding of deceptive emotions. The results are discussed in terms of the distinction between emotions as felt and emotions as a cognitive framework for understanding other people's actions and mental states. We conclude that children with head injury understand emotional communication, the spontaneous externalization of real affect, but not emotive communication, the conscious, strategic modification of affective signals to influence others through deceptive facial expressions.

'Oops!': performance correlates of everyday attentional failures in traumatic brain injured and normal subjects

Insufficient attention to tasks can result in slips of action as automatic, unintended action sequences are triggered inappropriately. Such slips arise in part from deficits in sustained attention, which are particularly likely to happen following frontal lobe and white matter damage in traumatic brain injury (TBI). We present a reliable laboratory paradigm that elicits such slips of action and demonstrates high correlations between the severity of brain damage and relative-reported everyday attention failures in a group of 34 TBI patients. We also demonstrate significant correlations between self- and informant-reported everyday attentional failures and performance on this paradigm in a group of 75 normal controls. The paradigm (the Sustained Attention to Response Task-SART) involves the withholding of key presses to rare (one in nine) targets. Performance on the SART correlates significantly with performance on tests of sustained attention, but not other types of attention, supporting the view that this is indeed a measure of sustained attention. We also show that errors (false presses) on the SART can be predicted by a significant shortening of reaction times in the immediately preceding responses, supporting the view that these errors are a result of 'drift' of controlled processing into automatic responding consequent on impaired sustained attention to task. We also report a highly significant correlation of -0.58 between SART performance and Glasgow Coma Scale Scores in the TBI group.

Motor and cognitive functional deficits following diffuse traumatic brain injury in the immature rat

To determine the motor and cognitive deficits following a diffuse severe traumatic brain injury (TBI) in immature Sprague Dawley rats (17 days), four groups of animals were injured at different severity levels using a new closed head weight drop model: (sham, severe injury [SI: 100 g/2 m], SH [SI + hypoxemia (30 min of an FiO2 of 8% posttrauma)], and ultra severe injury [US: 150 g/2 m]). Latency on beam balance, grip test performance, and maintenance of body position on an inclined board were measured daily after injury to assess vestibulomotor function. Cognitive function was assessed on days 11-22 using the Morris water maze (MWM). Balance beam latency and inclined plane body position were reduced in both SI and SH rats (n = 20) (p < 0.05 vs. sham) (maximally at 24 h), and lasted 3-4 day postinjury; however, SH did not differ from SI. In the US group (n = 10), motor deficits were profound at 24 h (p < 0.05 vs. all other groups) and persisted for 10 days. The groups did not differ on grip test. In cognitive performance, there were no differences between sham, SI, and SH. US, however, produced significant cognitive dysfunction (vs. sham, SI, and SH), specifically, greater latencies to find the hidden platform through 22 days. Swim speeds were not significantly different between any of the injury groups and shams. These data indicate that (1) beam balance, inclined plane and MWM techniques are useful for assessing motor and cognitive function after TBI in immature rats; (2) SI produces motor but not cognitive deficits, which was not augmented by transient hypoxia; and (3) US created a marked but reversible motor deficit up to 10 days, and a sustained cognitive dysfunction for up to 22 days after TBI.

Neuropsychological consequences of traumatic brain injury in children and adolescents

The study of the relationship between neuroscientific information and cognitive function and dysfunction is clearly a widely expanding field. In particular, there has been a growing body of research on traumatic brain injury (TBI) in children and adolescents. This article conveys recent findings concerning cognitive outcomes, with a particular focus on age differences with TBI, suggests a relationship between specific learning disorders and brain dysfunction, addresses differential hemisphere functioning with TBI, and alludes to recent developments in assessment of TBI.

Clinical neurological trauma parameters as predictors for neuropsychological recovery and long-term outcome in paediatric closed head injury: a review of the literature

We present a review of recent prospective studies of long-term outcome in paediatric closed head injury. Special attention is given to the relationship between the neurological trauma parameters and neuropsychological outcome. First we discuss the most important methods of assessing the severity of the injury. We review the most prominent neurobehavioural and cognitive sequelae. Subsequently we address the question of prediction of residual sequelae in view of the early trauma parameters. The main problem when comparing different studies is the lack of procedural uniformity both in assessment of the severity of the injury as well as in measurement of neuropsychological outcome. Inconsistencies and discrepancies among various studies are pointed out. We summarise those results which are supported by many studies and hence are less controversial. In addition we present some recommendations for future investigations.