Sentence processing in children with early unilateral brain injury

This study examined how children use word order and animacy cues to determine the agent of the action in an on-line sentence-comprehension task. The subject group included 15 children, 5-12 years old, with brain injury incurred prior to the age of 2 months; 12 had left hemisphere (LH) damage and 3 had right hemisphere (RH) damage. The comparison group included 141 children, 5-10 years old, who were at the appropriate grade for age. The task required children to listen to sentences composed of two noun phrases (N) that varied in terms of animacy and a verb phrase (V) and then to indicate the agent of the action. Three word orders were presented: NVN, VNN, and NNV. Measures included the proportion of trials in which the first noun was selected (choice) and reaction time. Word order and animacy significantly influenced choice. The effect of subject group approached significance for choice. Word order and age influenced reaction time. The children with LH injury and two children with RH injury showed a developmental delay in choosing the appropriate N as agent; one child with RH injury had mature responses. The overlapping performance of children with LH and RH injury suggests that delays in the development of sentence comprehension strategies are more likely related to reliance on a smaller than usual neural network rather than to congenital specialization of the LH.     

Narrative skill in children with early unilateral brain injury: a possible limit to functional plasticity

Children with pre‐ or perinatal brain injury (PL) exhibit marked plasticity for language learning. Previous work has focused mostly on the emergence of earlier‐developing skills, such as vocabulary and syntax. Here we ask whether this plasticity for earlier‐developing aspects of language extends to more complex, later‐developing language functions by examining the narrative production of children with PL. Using an elicitation technique that involves asking children to create stories de novo in response to a story stem, we collected narratives from 11 children with PL and 20 typically developing (TD) children. Narratives were analysed for length, diversity of the vocabulary used, use of complex syntax, complexity of the macro‐level narrative structure and use of narrative evaluation. Children’s language performance on vocabulary and syntax tasks outside the narrative context was also measured. Findings show that children with PL produced shorter stories, used less diverse vocabulary, produced structurally less complex stories at the macro‐level, and made fewer inferences regarding the cognitive states of the story characters. These differences in the narrative task emerged even though children with PL did not differ from TD children on vocabulary and syntax tasks outside the narrative context. Thus, findings suggest that there may be limitations to the plasticity for language functions displayed by children with PL, and that these limitations may be most apparent in complex, decontextualized language tasks such as narrative production.     

Face and location processing in children with early unilateral brain injury

Human visuospatial functions are commonly divided into those dependent on the ventral visual stream (ventral occipitotemporal regions), which allows for processing the ‘what’ of an object, and the dorsal visual stream (dorsal occipitoparietal regions), which allows for processing ‘where’ an object is in space. Information about the development of each of the two streams has been accumulating, but very little is known about the effects of injury, particularly very early injury, on this developmental process. Using a set of computerized dorsal and ventral stream tasks matched for stimuli, required response, and difficulty (for typically-developing individuals), we sought to compare the differential effects of injury to the two systems by examining performance in individuals with perinatal brain injury (PBI), who present with selective deficits in visuospatial processing from a young age. Thirty participants (mean = 15.1 years) with early unilateral brain injury (15 right hemisphere PBI, 15 left hemisphere PBI) and 16 matched controls participated. On our tasks children with PBI performed more poorly than controls (lower accuracy and longer response times), and this was particularly prominent for the ventral stream task. Lateralization of PBI was also a factor, as the dorsal stream task did not seem to be associated with lateralized deficits, with both PBI groups showing only subtle decrements in performance, while the ventral stream task elicited deficits from RPBI children that do not appear to improve with age. Our findings suggest that early injury results in lesion-specific visuospatial deficits that persist into adolescence. Further, as the stimuli used in our ventral stream task were faces, our findings are consistent with what is known about the neural systems for face processing, namely, that they are established relatively early, follow a comparatively rapid developmental trajectory (conferring a vulnerability to early insult), and are biased toward the right hemisphere.     

Cognitive development following early brain injury: evidence for neural adaptation

Over the past few decades a large body of work from developmental neurobiology has shown that mammalian brain development is the product of dynamic and adaptive processes operating within highly constrained, but continually changing, biological and environmental contexts. The recent study of children with prenatal focal brain injury supports this dynamic view of development for humans. Children's injuries often affect substantial portions of one cerebral hemisphere, resulting in damage that would compromise cognitive ability in adults. However, longitudinal behavioral studies of this population have revealed only mild deficits. It is suggested here that children's capacity for adaptation reflects normal developmental processes operating against a backdrop of serious neural perturbation. Data from three behavioral domains--linguistics, spatial cognition and affective development--illustrate this complex profile of change.     

Attachment and early reading: a longitudinal study

The relationship between quality of attachment in infancy and preschooler's reading interests and skills was explored. At 24 months, 77 children and their mothers were tested using the Strange Situation procedure. In a follow-up study 3 years later, 65 mothers completed a questionnaire about the reading interests and skills of their children. Preschool teachers completed a questionnaire about preparatory reading instruction, and the children's intelligence was measured with the Leiden Diagnostic Test. After 3 years, the securely attached children showed more interest in written material than did the insecurely attached children, regardless of their intelligence and the amount of preparatory reading instruction.     

Structuring of early reaching movements: a longitudinal study

Reaches, performed by 5 infants, recorded at 19 weeks of age and every third week thereafter until 31 weeks of age, were studied quantitatively. Earlier findings about action units were confirmed. At all ages studied, movements were structured into phases of acceleration and deceleration. Reaching trajectories were found to be relatively straight within these units and to change direction between them. It was also found that at all ages, there was generally one dominating transport unit in each reach. The structuring of reaching movements changed in four important ways during the period studied. First, the sequential structuring became more systematic with age, with the dominating transport unit beginning the movement. Second, the duration of the transport unit became longer and covered a larger proportion of the approach. Third, the number of action units decreased with age, approaching the two-phase structure of adult reaching. Finally, reaching trajectories became straighter with age.     

Prosocial development in early adulthood: a longitudinal study

Consistency of measures of a prosocial personality and prosocial moral judgment over time, and the interrelations among them, were examined. Participants and friends' reports of prosocial characteristics were obtained at ages 21-22, 23-24, and 25-26 years. In addition, participants' prosocial judgment was assessed with interviews and with an objective measure of prosocial moral reasoning at several ages. Reports of prosocial behavior and empathy-related responding in childhood and observations of prosocial behavior in preschool also were obtained. There was interindividual consistency in prosocial dispositions, and prosocial dispositions in adulthood related to empathy/sympathy and prosocial behavior at much younger ages. Interview and objective measures of moral reasoning were substantially interrelated in late adolescence/early adulthood and correlated with participants' and friends' reports of a prosocial disposition.     

Normality and impairment following profound early institutional deprivation: a longitudinal follow-up into early adolescence

Longitudinal analyses on normal versus impaired functioning across 7 domains were conducted in children who had experienced profound institutional deprivation up to the age of 42 months and were adopted from Romania into U.K. families. Comparisons were made with noninstitutionalized children adopted from Romania and with nondeprived within-U.K. adoptees placed before the age of 6 months. Specifically, the validity of the assessment, the degree of continuity and change in levels of functioning from 6 to 11 years, and the factors in the pre- and postadoption environment accounting for heterogeneity in outcome were examined. Pervasive impairment was significantly raised in children experiencing institutional deprivation for > or =6 months of life, with a minority within this group showing no impairment. There was no additional significant effect of duration of deprivation beyond the 6-month cutoff, and few other predictors explained outcome. The pattern of normality/impairment was mainly established by 6 years of age, with considerable continuity at the individual level between 6 and 11 years. The findings are discussed in terms of the possibility of a sensitive period for development.     

Language development after unilateral brain injury.

This longitudinal study describes the growth of syntactic abilities and vocabulary size in nine children with unilateral antepartum or perinatal brain injury. Five children with left hemisphere damage (LHD) and four with right hemisphere damage (RHD), ages 15 to 48 months, were evaluated on three or more occasions. Language samples generated from parent-child interaction were transcribed, coded, and analyzed using the Child Language Data Exchange System. Individual growth trajectories were constructed by graphing three dependent variables--MLU, scores on the Index of Productive Syntax (IPSYN), and number of different words--as a function of the child's age. One subject remained in a prelinguistic stage throughout the study. Simple linear functions best described the growth of MLU, IPSYN scores, and vocabulary in the other eight children. The slopes of the individual growth trajectories, the graphic representations of rates of progress, were comparable in the eight children. Seven children showed developmental delays in initial word use and five in the onset of multiword utterances. However, by age 24 months, four children with LHD and two children with RHD had syntactic capabilities comparable to those of children without brain injuries. The developmental patterns suggested that both cerebral hemispheres may play critical roles in the very earliest stages of language acquisition. Some unilateral lesions caused little discernible effect on language outcome in the toddler-preschool years after the initial developmental delays.     

Maturation of EEG power spectra in early adolescence: a longitudinal study

This study investigated the fine-grained development of the EEG power spectra in early adolescence, and the extent to which it is reflected in changes in peak frequency. It also sought to determine whether sex differences in the EEG power spectra reflect differential patterns of maturation. A group of 56 adolescents were tested at age 10 years and then at two further time-points approximately 18 months apart. The EEG was recorded during both eyes-closed and eyes-open conditions and Fourier transformed to provide estimates of absolute and relative spectral power at 0.5 Hz intervals from 0.5 to 40 Hz. The peak alpha frequency for each individual at each time-point was also determined for relative spectral power. Partial Least Squares (PLS) analysis was used to determine the combination of electrodes and frequencies that showed developmental change, or differed between the sexes. As a function of age, absolute delta and theta frequencies power decreased, and relative alpha2 and beta frequencies increased, replicating the standard findings of a decrease in lower, and increase in higher, frequencies with age. A small but significant increase in peak alpha frequency with age was detected. Moreover PLS analysis performed with individual alpha frequencies aligned to 10 Hz suggested that the age-related increase seen in alpha2 relative power was driven by changes in the peak frequency. Although males demonstrated higher alpha power than females, there were no sex differences in peak frequency, suggesting that there may be more to sex differences in EEG power than simply different rates of maturation between the two sexes.     

Recovery of intellectual function after a brain injury: a comparison of longitudinal and cross-sectional approaches

The goal of this study was to investigate recovery of intellectual function as a function of age at the time of a brain lesion. Participants with unilateral cortical lesions were selected from an initial data base of 685 patients. Ninety-six participants formed a longitudinal cohort for a first study and 314 participants formed a cross-sectional cohort for a second study. Participants of each study were split into two age groups according to the age at the time of the lesion: (1) before 7 years, (2) 7 years or more. Results showed a significantly different recovery profile as a function of age in the longitudinal study. Older participants manifested recovery on VIQ and PIQ, while younger participants presented stable profiles. The longitudinal and cross-sectional studies revealed differing recovery profiles as a function of age. Results are discussed in the context of the Kennard principle and with regard to the methodological approaches.     

Psychosocial issues following traumatic brain injury

The author contends that Dean, Colantonio, Ratcliff, and Chase in 2000 probably underestimated the importance of psychosocial factors in the very long-term adaptation to disability by 166 individuals with traumatic brain injury.     

IQ change and occupational level: A longitudinal study with Third Harvard Growth Study participants

Eighty subjects from a larger number of participants in a longitudinal study were selected according to their 1916 Stanford-Binet Intelligence Test scores, administered in the 1930s, and their 1977 occupations. They were then individually administered the Wechsler Adult Intelligence Scale. The research questions asked were: Did subjects shift their positions relative to age peers with regard to measured intelligence from Time 1 (1930s) testing to Time 2 (1977) testing? And, if they did, were these shifts related to their occupational levels? A secondary question asked whether subjects as a group showed mean T score increments between test times. A Pearson correlation coefficient (r = .62) showed that subjects had significantly maintained their positions relative to peers with regard to measured intelligence over approximately one-half of a century. The hypothesis that persons in higher level occupations should show greater gains in measured intelligence over time was not supported. Using multiple regression procedures, no significant difference was found from analysis of effects of occupational level on D (D = T₂ ? T₁) scores. An 80-subject mean T score increase (M = +8.13) was found. This represented an average increase of four-fifths of a standard deviation in T score units. These data suggest that, on average, persons increase in mental abilities over time while maintaining IQ positions relative to peers and that those changes in IQ which do occur are not related to occupational level experience.     

Correlates of memory decline: a 4-year longitudinal study of older adults with memory complaints.

Change in memory performance and its correspondence to change in speed of performance and self-reported memory functioning were investigated longitudinally in 30 older adults with memory complaints. Subjects were assessed by self-report questionnaires and cognitive tests 3 times, at near 2-year intervals. A significant decline in word-recall scores was found, which was accompanied at the group level by significant self-reported decline in everyday memory functioning and nonsignificant decline in Wechsler Adult Intelligence Scale Digit Symbol scores (alpha = .05). The oldest subjects showed the most substantial declines in memory performance. At the individual level, however, memory change did not significantly correlate with either change in self-reports or change in Digit Symbol scores. Although these results do not support a cognitive slowing model of decline at the intraindividual level, they do have implications for intervention of age-related memory decline.     

Neurocognitive outcomes following pediatric brain injury: A developmental approach

Developmental neuropsychologists postulate that “immaturity” of the cerebral cortex should no longer be perceived as a protective factor. They argue that injury to the young brain may affect new learning by disrupting the skills in the midst of being acquired and skills that are yet to be developed. Cognitive deficits or weaknesses that are not detectable in the acute phase following a traumatic brain injury (TBI) may emerge over development as more complex skills are needed, thereby creating a developmental lag between children who sustained a pediatric TBI and typical age peers. This literature review was conducted to evaluate the developmental perspective on neurocognitive recovery/development following a TBI. Overall, the described findings support a developmental view and suggest that predictions of prognosis should be based on the child's remaining ability to learn.     

Traumatic stress symptoms following a lower limb amputation in diabetic patients: a longitudinal study

Objective: Limited research has focussed on the development of traumatic stress symptoms following an amputation due to a chronic disease such as Diabetes. This study analysed whether coping strategies, anxiety and depression symptoms, sociodemographic and clinical variables were related to traumatic stress symptoms in a sample of patients who had undergone a lower limb amputation.

Design: A longitudinal design with three assessments, one month (T1), six (T2) and ten months after an amputation surgery (T3), included 144 patients.

Main outcome measures: IES-R, WOC and HADS.

Results: Traumatic stress symptoms were prevalent at T1 (M?=?15.65, SD?=?15.40) and probable PTSD was observed in 13.9% patients. Presence of pain, high level of anxiety symptoms and emotion-focused strategies contributed to traumatic stress symptoms, and the period between T1 and T2, was critical. Six to ten months (Λ?=?0.871, F (2,84) =6.245, p=. 003), after surgery, symptoms tended to decrease 0.122 units (SE?=?0.032, p?=?0.002) per assessment.

Conclusions: Findings raise awareness to the need of urgent identification of traumatic stress symptoms in medically ill patients who underwent a lower limb amputation, given the prevalence of traumatic stress symptoms right after surgery and in the following six months.     

A study of emotionalism in patients undergoing rehabilitation following severe acquired brain injury

The present study describes the phenomenon of emotionalism in a sample of brain injured patients of mixed aetiology, with a view to identifying issues relevant to clinical management, and possible causal factors. 82 subjects with severe acquired brain injury undergoing rehabilitation participated in a structured interview in which they were asked to report the presence/absence of emotionalism and degree of distress associated with it. Their overt crying behaviour was also observed and recorded. Independent variables that predicted crying during the interview were identified using a multiple logistic regression procedure. Prevalence rates of emotionalism-tearfulness were high in this sample (52% self-report, 36--41% Emotionalism-laughter was much less common (13%) Emotionalism-tearfulness was usually accompanied by negative affect, occurred in response to identifiable precipitants, and was often controllable. It was associated with major personal distress in about half the subjects who reported it. Independent variables which predicted crying behaviour were female gender and focal damage to the right cerebral hemisphere. It is concluded that an increased readiness to cry is common in people with severe acquired brain injury of mixed aetiology. The behaviour is meaningful, though not always distressing. The intensity of the behaviour is variable, and it may be most appropriate to regard emotionalism as a dimension rather than a syndrome. Implications for clinical management are discussed.