Hemispheric visual atentional imbalance in patients with traumatic brain injury

We find a spatially asymmetric allocation of attention in patients with traumatic brain injury (TBI) despite the lack of obvious asymmetry in neurological indicators. Identification performance was measured for simple spatial patterns presented briefly to a locus 5 degrees into the left or right hemifield, after precuing attention to the same (ipsilateral) or opposite (cross-hemifield) side. Though the cue was non-predictive of target location overall, performance was significantly slower for cross than for ipsilateral trials in both patients and controls. We tested 21 TBI patients without overt focal brain damage and nine control subjects. Only patients demonstrated significantly worse performance for left side presentation in the ipsilateral condition. Furthermore, in the cross-hemifield condition, the left-right difference seen in TBI patients was significantly larger-reflecting a failure in producing a leftward attention shift. Again no significant difference was found in controls. These hemifield effects suggest an asymmetry in the ability of TBI patients in shifting attention to the left hemifield, whether from central fixation or from a cue in the contra-lateral hemifield. The results support basic hypotheses regarding visual attention: Attentional control may be asymmetric and attention may be a distributed, rather than localized cortical function.     

Time perception and time perspective differences between adolescents and adults

The present experiment aimed to investigate the differences in time perception and time perspective between subjects representing two developmental stages, namely adolescence and middle adulthood. Twenty Chinese adolescents aged 15–25 and twenty Chinese adults aged 35–55 participated in the study. A time discrimination task and a time reproduction task were implemented to measure the accuracy of their time perception. The Zimbardo Time Perspective Inventory (Short-Form) was adopted to assess their time orientation. It was found that adolescents performed better than adults in both the time discrimination task and the time reproduction task. Adolescents were able to differentiate different time intervals with greater accuracy and reproduce the target duration more precisely. For the time reproduction task, it was also found that adults tended to overestimate the duration of the target stimuli while adolescents were more likely to underestimate it. As regards time perspective, adults were more future-oriented than adolescents, whereas adolescents were more present-oriented than adults. No significant relationship was found between time perspective and time perception.     

Regional cortical volume and cognitive functioning following traumatic brain injury

There has been limited examination of the effect of brain pathology on subsequent function. The current study examined the relationships between regional variation in grey matter volume, age and cognitive impairment using a semi-automated image analysis tool. This study included 69 individuals with mild-to-severe TBI, 41 of whom also completed neuropsychological tests of attention, working memory, processing speed, memory and executive functions. A widespread reduction in grey matter volume was associated with increasing age. Regional volumes that were affected also related to the severity of injury, whereby the most severe TBI participants displayed the most significant pathology. Poorer retention of newly learned material was associated with reduced cortical volume in frontal, parietal, and occipital brain regions. In addition, poorer working memory and executive control performance was found for individuals with lower cortical volume in temporal, parietal, and occipital regions. These findings are largely in line with previous literature, which suggests that frontal, temporal, and parietal regions are integral for the encoding of memories into long-term storage, memory retrieval, and working memory. The present study suggests that automated image analysis methods may be used to explore the relationships between regional variation in grey matter volume and cognitive function following TBI.     

Executive function outcomes of children with traumatic brain injury sustained before three years

Traumatic brain injury (TBI) is a common cause of disability in childhood. While the outcomes of TBI sustained in school years has been heavily researched, very little is known about the impact of TBI in infants and young children. The aim of this study was to investigate the impact of TBI on executive function (EF) in children who sustained a TBI before 3 years of age. A group of 55 children, 19 with a mild TBI, 16 children with a moderate-severe TBI, and 20 uninjured comparison children participated. The EF of children aged 3 to 6 years were compared using child-based measures of attentional control and information processing. Parents completed questionnaires rating their child's EF. Severity groups differed on the child-based EF measure of attentional control with children with TBI performing below the control group. There were no significant group differences for information processing or parent-rated EF. It appears that children who sustain a TBI before the age of 3 years display impairments in some areas of attentional control 3–4 years postinjury. The findings fit with the existing EF literature for older children.     

Liberal bias mediates emotion recognition deficits in frontal traumatic brain injury

It is well-known that patients having sustained frontal-lobe traumatic brain injury (TBI) are severely impaired on tests of emotion recognition. Indeed, these patients have significant difficulty recognizing facial expressions of emotion, and such deficits are often associated with decreased social functioning and poor quality of life. As of yet, no studies have examined the response patterns which underlie facial emotion recognition impairment in TBI and which may lend clarity to the interpretation of deficits. Therefore, the present study aimed to characterize response patterns in facial emotion recognition in 14 patients with frontal TBI compared to 22 matched control subjects, using a task which required participants to rate the intensity of each emotion (happiness, sadness, anger, disgust, surprise and fear) of a series of photographs of emotional and neutral faces. Results first confirmed the presence of facial emotion recognition impairment in TBI, and further revealed that patients displayed a liberal bias when rating facial expressions, leading them to associate intense ratings of incorrect emotional labels to sad, disgusted, surprised and fearful facial expressions. These findings are generally in line with prior studies which also report important facial affect recognition deficits in TBI patients, particularly for negative emotions.     

Working memory outcomes following traumatic brain injury in children: A systematic review with meta-analysis

The aim of this review is to systematically examine the literature concerning multicomponent working memory (WM)—comprising a central executive (CE), two storage components (phonological loop, PL and visuo-spatial sketchpad, VSSP), and episodic buffer (EB)—in pediatric traumatic brain injury (TBI). Electronic searches were conducted of MEDLINE, PsychINFO and EMBASE up to October 2014 with the inclusion criteria of children and adolescents with TBI, and quantitative methods to assess at least one component of WM. Meta-analytic procedures calculated pooled effect sizes for WM outcomes. Of the studies examined, 27 met the inclusion criteria. Children with TBI exhibited deficits in the CE and PL, but not in the VSSP, and no study could be found which examined the EB. Qualitative analysis found that greater TBI severity was associated with poorer CE functioning in five out of nine studies. Differences in patterns of brain activation were evident in four out of five fMRI studies that examined WM in TBI children and controls. Deficits in CE were associated with poorer mathematical skills in the only study that examined relations between WM and academic deficits. Notwithstanding the heterogeneity of the studies reviewed, TBI places children at risk of WM deficits. Moreover, this meta-analysis suggests that various components of WM have differential vulnerability to pediatric TBI, with significant deficits found in the CE and PL, but not in the VSSP (although the VSSP has rarely been examined to date). Future studies should be theoretically driven, employ tasks assessing all components of the WM model and examine the functional ramifications (including academic outcomes) of WM deficits in this population.     

Disfluency clusters in speakers with and without neurogenic stuttering following traumatic brain injury

PurposeAnalyze the characteristics and rate of disfluency clusters in adults with and without neurogenic stuttering after traumatic brain injury (TBI).MethodTwenty adults with TBI participated in this study, including 10 with neurogenic stuttering (Group B) and 10 without -stuttering (Group A). Disfluency clusters in speech samples were classified into three types: Stuttering-like (SLD), other (OD), and mixed (MIX).ResultsSpeakers with and without neurogenic stuttering produced the same mean number of disfluency clusters. In addition, the mean length of clusters did not differ between these speaker groups although the longest clusters did. The most frequently occurring cluster type for people with neurogenic stuttering was MIX and OD for people without stuttering. Although the speakers in Group A produced stuttering-like disfluencies, these never occurred together to form a SLD type cluster. For Group B, the starter units of the clusters were usually stuttering-like disfluencies, while for Group A, the starter units were mostly interruptions.ConclusionsCompared to non-stuttering speakers, stuttering after TBI did not increase the number of clusters, but rather lengthened them. In speakers with neurogenic stuttering, the number and length of clusters were related to the manifestation of other communication deficits, not to the frequency of stuttering-like disfluencies. Still, SLD clusters occurred only in those people with neurogenic stuttering. These findings raise questions about the nature of both neurogenic stuttering and the dynamics of disfluency clustering.     

Attentional distractor interference may be diminished by concurrent working memory load in normal participants and traumatic brain injury patients

A reduction in congruency effects under working memory (WM) load has been previously described using different attentional paradigms (e.g.,  and ). One hypothesis is that different types of WM load have different effects on attentional selection, depending on whether a specific memory load demands resources in common with target or distractor processing. In particular, if information in WM is related to the distractors in the selective attention task, there is a reduction in distraction (Kim et al., 2005). However, although previous results seem to point to a decrease in interference under high WM load conditions (Kim et al., 2005), the lack of a neutral baseline for the congruency effects makes it difficult to differentiate between a decrease in interference or in facilitation. In the present work we included neutral trials in the task introduced by Kim et al. (2005) and tested normal participants and traumatic brain injury patients. Results support a reduction in the processing of distractors under WM load, at least for incongruent trials in both groups. Theoretical as well as applied implications are discussed.     

Long-term ability to interpret facial expression after traumatic brain injury and its relation to social integration

There is considerable evidence that individuals with traumatic brain injury (TBI) experience problems interpreting the emotional state of others. However, the functional implications of these changes have not been fully investigated. A study of 13 individuals with severe TBI and an equal number of matched controls found that TBI participants had significantly more difficulty interpreting facial expression and matching emotions to social situations. A significant relationship was also established between social integration and ability to interpret facial expression for TBI participants. These results support the inclusion of therapy targeting this area within rehabilitation programs for individuals with TBI.     

Generalizability of WISC-IV index and subtest score profiles in children with traumatic brain injury

The Wechsler Intelligence Scale for Children, 4th edition (WISC-IV) is often used to assess children with traumatic brain injury (TBI); although limited information is available regarding its psychometric properties in these children. Two recent reports suggest that the Perceptual Reasoning Index is not uniquely sensitive to TBI, which differs from the Perceptual Organization Index of the WISC-III. The current study examined WISC-IV profiles in two independently gathered samples of children with TBI. Examination of profiles indicated similarities between the current findings and those reported in other studies, in that the greatest deficits were present on the Processing Speed Index and its component subtests of Coding and Symbol Search, while the Perceptual Reasoning index score was comparable to the Verbal Comprehension Index. Also, no significant index or subtest score differences were present when the current sample was compared to the children with TBI reported by Allen, Thaler, Donohue and Mayfield (2010 Allen, D. N., Thaler, N. S., Donohue, B. and Mayfield, J. 2010. WISC-IV profiles in children with traumatic brain injury: Similarities to and differences from the WISC-III. Psychological Assessment, 22(1): 57–64. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). The present findings are consistent with two prior studies of the WISC-IV in children with TBI, providing additional evidence for profile differences between the WISC-III and WISC-IV. The results also suggest that WISC-IV profiles reported in prior studies are generalizable across TBI samples and study sites.     

Metamemory following childhood brain injury: A consequence of executive impairment

In this study, we investigated the influence of children’s level of executive functioning on two types of metamemory knowledge following a traumatic brain injury (TBI). For this purpose, 22 children (aged 7 to 14 years) who had sustained a moderate to severe TBI and 44 typically developing children were recruited. The children with TBI were divided into two groups according to the severity of their executive impairment. Injury severity was determined by the Glasgow Coma Scale (GCS) score on admission or by the duration of unconsciousness. All children were then tested on both their knowledge of general memory functioning and their level of memory self-awareness, respectively assessed using the total number of correct responses on an adapted version of a metamemory interview and a self-other discrepancy score on a questionnaire evaluating everyday memory abilities. Data analyses revealed that participants with TBI who suffered impaired executive functions demonstrated less general metamemory knowledge, and underestimated the frequency of their memory problems, compared with children with TBI who had preserved executive functions and with control participants. Considering the well-established effect of metamemory knowledge on people’s spontaneous implementation of strategies, the interest and the importance of these findings on both theoretical and clinical grounds are discussed.     

Traumatic brain injury: Implications for practice

This article presents a brief overview of the prevalence and history of traumatic brain injury (TBI), discusses the multidimensional effects of TBI, describes the current focus of TBI rehabilitation, and summarizes outcomes from (re)habilitation work with individuals with traumatic brain injury. The importance of this critical area to rehabilitation personnel is discussed, along with suggestions for future research and evaluation studies.     

Traumatic brain injury: Implications for practice

This article presents a brief overview of the prevalence and history of traumatic brain injury (TBI), discusses the multidimensional effects of TBI, describes the current focus of TBI rehabilitation, and summarizes outcomes from (re)habilitation work with individuals with traumatic brain injury. The importance of this critical area to rehabilitation personnel is discussed, along with suggestions for future research and evaluation studies.     

Development and preliminary validation of the Paediatric Awareness Questionnaire for children and adolescents with traumatic brain injury

There is a lack of validated measures for assessing self-awareness of deficits after pediatric traumatic brain injury (TBI). The current study aimed to develop and examine the psychometric properties of the Paediatric Awareness Questionnaire (PAQ), and investigate factors related to self-awareness. The PAQ was administered to 32 children aged 8–16 years with mild to severe TBI (72% male, M age = 11.75, SD = 2.9), their parents, and treating clinicians, and to 32 age- and gender-matched typically developing controls and their parents. Children with TBI and their parents also completed the Knowledge of Injury Checklist (KIC), and parents completed the Depression Anxiety and Stress Scale 21. The PAQ was found to have fair to excellent (α = .79–.97) internal consistency for all versions across both groups and good concordance between parent and clinician total scores (ICC = .78). There was also evidence of convergent validity between the PAQ and KIC for both child (r = ?.45, p < .05) and parent ratings (r = ?.66, p < .001). Poorer self-awareness was significantly related to younger age at injury for the TBI group and lower parental education for the total sample. ANCOVA identified that children with TBI demonstrated significantly poorer awareness than controls after controlling for parental education. Children with TBI typically overestimated their functioning compared to their parents, whereas typically developing children tended to rate their functioning lower than their parents. These findings provide preliminary support for the reliability and validity of the PAQ for assessing self-awareness after pediatric TBI.     

Cognitive reserve as a moderator of responsiveness to an online problem-solving intervention for adolescents with complicated mild-to-severe traumatic brain injury

Children and adolescents with traumatic brain injury (TBI) often experience behavior difficulties that may arise from problem-solving deficits and impaired self-regulation. However, little is known about the relationship of neurocognitive ability to post-TBI behavioral recovery. To address this question, we examined whether verbal intelligence, as estimated by Vocabulary scores from the Wechsler Abbreviated Scale of Intelligence, predicted improvements in behavior and executive functioning following a problem-solving intervention for adolescents with TBI. One hundred and thirty-two adolescents with complicated mild-to-severe TBI were randomly assigned to a six-month Web-based problem-solving intervention (CAPS; n = 65) or to an Internet resource comparison (IRC; n = 67) group. Vocabulary moderated the association between treatment group and improvements in metacognitive abilities. Examination of the mean estimates indicated that for those with lower Vocabulary scores, pre-intervention Metacognition Index scores from the Behavior Rating Inventory of Executive Function (BRIEF) did not differ between the groups, but post-intervention scores were significantly lower (more improved) for those in the CAPS group. These findings suggest that low verbal intelligence was associated with greater improvements in executive functioning following the CAPS intervention and that verbal intelligence may have an important role in response to intervention for TBI. Understanding predictors of responsiveness to interventions allows clinicians to tailor treatments to individuals, thus improving efficacy.     

A review of social disinhibition after traumatic brain injury

Acquired social disinhibition refers to a debilitating behavioural syndrome commonly reported after a severe traumatic brain injury (TBI) and is characterized by inappropriate social behaviour, often described as immaturity and insensitivity towards others. These behaviours can have enduring effects on the social capability of the individual and their relationships with others. However, research into socially disinhibited behaviour after TBI has been thwarted by a lack of consensus in the literature on definition and measurement. This review provides an overview of our current understanding of the definition, measurement, prevalence, associated outcomes, neuropathology, and underlying mechanisms of social disinhibition after TBI. In addition, suggestions are made for future research to further our understanding of this syndrome with the eventual aim of rehabilitating problematic behaviours. It is concluded that an improved understanding of what causes disinhibited behaviour after TBI will be necessary for the development of effective treatment strategies aimed at the rehabilitation of underlying impairments.     

An attempt towards differentiating attentional deficits in traumatic brain injury

Attentional deficits in patients suffering traumatic brain injury (TBI) can occur with minor to severe impact to the brain. Based on reviews of both the cognitive and neurobehavioral literature, the following three concepts of attention are addressed: (a) arousal/alertness, (b) selective attention, and (c) energetic aspects of attention, which include such components as effort, resource allocation, and speed of processing. Within each concept, definitions are proposed, the underlying brain mechanisms are identified, and the specific deficits associated with TBI are explored. This review combines theoretical perspectives and clinical findings with the objective of leading toward a diagnostic differentiation that in turn will benefit treatment planning.