Cognitive Functioning,Behavior, and Quality of Life After Stroke in Childhood

Rationale: To provide a better understanding of cognitive functioning, motor outcome, behavior and quality of life after childhood stroke and to study the relationship between variables expected to influence rehabilitation and outcome (age at stroke, time elapsed since stroke, lateralization, location and size of lesion).

Methods: Children who suffered from stroke between birth and their eighteenth year of life underwent an assessment consisting of cognitive tests (WISC-III, WAIS-R, K-ABC, TAP, Rey-Figure, German Version of the CVLT) and questionnaires (Conner's Scales, KIDSCREEN).

Results: Twenty-one patients after stroke in childhood (15 males, mean 11;11 years, SD 4;3, range 6;10–21;2) participated in the study. Mean Intelligence Quotients (IQ) were situated within the normal range (mean Full Scale IQ 96.5, range IQ 79–129). However, significantly more patients showed deficits in various cognitive domains than expected from a healthy population (Performance IQ p?=?.000; Digit Span p?=?.000, Arithmetic's p?=?.007, Divided Attention p?=?.028, Alertness p?=?.002). Verbal IQ was significantly better than Performance IQ in 13 of 17 patients, independent of the hemispheric side of lesion. Symptoms of ADHD occurred more often in the patients' sample than in a healthy population (learning difficulties/inattention p?=?.000; impulsivity/hyperactivity p?=?.006; psychosomatics p?=?.006). Certain aspects of quality of life were reduced (autonomy p?=?.003; parents' relation p?=?.003; social acceptance p?=?.037). Three patients had a right-sided hemiparesis, mean values of motor functions of the other patients were slightly impaired (sequential finger movements p?=?.000, hand alternation p?=?.001, foot tapping p?=?.043). In patients without hemiparesis, there was no relation between the lateralization of lesion and motor outcome. Lesion that occurred in the midst of childhood (5–10 years) led to better cognitive outcome than lesion in the very early (0–5 years) or late childhood (10–18 years). Other variables such as presence of seizure, elapsed time since stroke and size of lesion had a small to no impact on prognosis.

Conclusion: Moderate cognitive and motor deficits, behavioral problems, and impairment in some aspects of quality of life frequently remain after stroke in childhood. Visuospatial functions are more often reduced than verbal functions, independent of the hemispheric side of lesion. This indicates a functional superiority of verbal skills compared to visuospatial skills in the process of recovery after brain injury. Compared to the cognitive outcome following stroke in adults, cognitive sequelae after childhood stroke do indicate neither the lateralization nor the location of the lesion focus. Age at stroke seems to be the only determining factor influencing cognitive outcome.     

Neuropsychological sequelae following pediatric stroke: A nonlinear model of age at lesion effects

Aim: The distribution and quality of brain recovery following pediatric arterial ischemic stroke remains controversial. The literature suggests that age at stroke may be an important modulator of neuropsychological outcome, with reports inferring either greater vulnerability or plasticity in the nascent brain. Our aim was to investigate neuropsychological outcomes following pediatric stroke in a clinical sample with reference to age at lesion, lesion laterality, elapsed time from stroke to assessment, and persistent neurological sequelae.

Methods: Using comprehensive neuropsychological assessment batteries, we investigated retrospectively a large (n?=?44) and evenly distributed group of children who had ischemic stroke during “infancy” (1 month to 1 year), “early childhood” (1 to 6 years), and “late childhood” (6 to 16 years).

Results: Children who suffered a stroke performed significantly worse on a range of neuropsychological measures when compared to a normative sample. However, children who suffered a stroke between 1 and 6 years old demonstrated better preserved neuropsychological profiles than either the earlier (before age 1) or later (after age 6) age groups. In addition, those children suffering a left hemisphere lesion performed more poorly on a range of neuropsychological measures than did children with right hemisphere lesions.

Interpretation: Age at stroke is an important determinant of recovery following insult and may modulate neuropsychological and cognitive outcome.     

Is body mass index in old age related to cognitive abilities? The Lothian Birth Cohort 1936 Study

We tested the hypothesis that the previously reported association between a higher body mass index (BMI) and poorer cognition in later adulthood is an artifact of confounding by previous cognitive ability and socioeconomic status. Participants were 1,079 adults aged about 70 years in the Lothian Birth Cohort 1936 Study, on whom there are IQ data from age 11. Cognitive outcome measures included: IQ at age 70 using the same test that was administered at age 11; composite measures of general cognitive ability (g factor), speed of information processing, and memory; and two tests of verbal ability. People classified as overweight or obese in later adulthood had significantly lower scores on tests of childhood IQ, age 70 IQ, g factor, and verbal ability. There was no significant association with processing speed or memory performance. After adjusting for childhood IQ and social class in general linear models, associations with age 70 IQ and g factor were nonsignificant or attenuated. However, throughout the models, there was a persistent (inverse) relationship between BMI and performance on the National Adult Reading Test (NART) and Wechsler Test of Adult Reading (WTAR), which remained significant after full adjustment for all sociodemographic and health covariates (for the NART, p = .025; for the WTAR, p = .011). The findings suggest that the previously reported BMI-cognition associations in later adulthood could be largely accounted for by prior ability and socioeconomic status, and by the possible influence of these factors on the adoption of health behaviors in adulthood.     

Typical intellectual engagement and cognition in the ninth decade of life: The Lothian Birth Cohort 1921

Investment traits-the tendency to seek out and engage in cognitive activity-might affect intellectual growth across the life span, specifically the development from fluid to crystallized intelligence. Here we explore how childhood IQ at age 11 years, IQ at age 79, and the investment trait Typical Intellectual Engagement (TIE) at age 81 affect the mean level and change in verbal fluency scores, used as an indicator of crystallized intelligence, across the ages 79, 83, and 87 in the Lothian Birth Cohort 1921 (maximum N = 569; Deary, Whiteman, Starr, Whalley, & Fox, 2004). A first latent growth model showed significant variance in the mean level of verbal fluency and significant decline in verbal fluency from age 79 to age 87. The rate of change was invariant across study participants in the Lothian Birth Cohort 1921. A second model found that IQ at age 11 significantly predicted IQ at age 79 (β = .66; p < .001), which in turn predicted verbal fluency and TIE in the ninth decade of life with standardized path parameters of .46 and .15 (p < .001), respectively. TIE had a significant association with verbal fluency (β = .14, p = .002); together, IQ at age 11 and 79 and TIE accounted for 25.5% of the variance in verbal fluency. A final model identified the TIE subfactor of intellectual curiosity as a significant mediator of the effect of IQ on verbal fluency; the TIE subfactors abstract thinking, reading, and problem solving showed no significant associations. In summary, TIE-in particular, intellectual curiosity-significantly mediated the effects of IQ on crystallized intelligence in old age. Because there was no significant between-subjects variance in verbal fluency trajectories in the current study, neither TIE nor IQ were associated with individual differences in cognitive decline. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

The impact of childhood intelligence on later life: following up the Scottish mental surveys of 1932 and 1947

The Scottish Mental Surveys of 1932 and 1947 collected valid IQ-type test scores for almost everyone born in 1921 and 1936 and attending school on June 1, 1932 (N=89,498) and June 4, 1947 (N=70,805). These surveys are described. This research, using the surveys' data, examined (a) the stability of intelligence differences across the life span, (b) the determinants of cognitive change from childhood to old age, and (c) the impact of childhood intelligence on survival and health in old age. Surviving participants of the Scottish Mental Surveys were tested, and the surveys' data were linked with public and health records. Novel findings on the stability of IQ scores from age 11 to age 80; sex differences in cognitive aging; the dedifferentiation hypothesis of cognitive aging; and the effect of childhood IQ on all-cause and specific mortality, morbidity, and frailty in old age are presented.     

Language comprehension vs. language production: age effects on fMRI activation

Normal language acquisition is a process that unfolds with amazing speed primarily in the first years of life. However, the refinement of linguistic proficiency is an ongoing process, extending well into childhood and adolescence. An increase in lateralization and a more focussed productive language network have been suggested to be the neural correlates of this process. However, the processes underlying the refinement of language comprehension are less clear. Using a language comprehension (Beep Stories) and a language production (Vowel Identification) task in fMRI, we studied language representation and lateralization in 36 children, adolescents, and young adults (age 6-24 years). For the language comprehension network, we found a more focal activation with age in the bilateral superior temporal gyri. No significant increase of lateralization with age could be observed, so the neural basis of language comprehension as assessed with the Beep Stories task seems to be established in a bilateral network by late childhood. For the productive network, however, we could confirm an increase with age both in focus and lateralization. Only in the language comprehension task did verbal IQ correlate with lateralization, with higher verbal IQ being associated with more right-hemispheric involvement. In some subjects (24%), language comprehension and language production were lateralized to opposite hemispheres.     

Attention,Memory, and Language after Pediatric Ischemic Stroke

A previous study evaluating receptive language after unilateral brain damage in childhood hypothesized lateralized attention and memory deficits without direct measurement. Our study directly measured attention, memory, and language in order to evaluate empirically the severity and laterality of sequelae. The performances of 11 individuals with a unilateral ischemic-lesion (7 right and 4 left hemisphere) were compared to controls matched on age, sex, and socioeconomic status. Results suggest subtle but persistent deficits in verbal memory, functional memory, and speed of processing after a lesion to either hemisphere. Lesions sustained before two years of age were associated with the lowest IQ scores. Our findings provide support for a configural representation of language that can to some extent compensate for inefficient or damaged components (Bates, 1994), and the middle-ground lateralization position (Thal et al., 1991) that asserts initial hemispheric specialization with the potential for reorganization.     

Prevalence,and intellectual outcome of unilateral focal cortical brain damage as a function of age,sex and aetiology

Neurologists and neuropsychologists are aware that aging men are more at risk than women for brain damage, principally because of the well known male-predominant risk for cardiovascular disease and related cerebrovascular accidents. However, a disproportion in prevalence of brain damage between the sexes in childhood may be less suspected. Furthermore, sex-specific risk for other aetiologies of brain damage may be little known, whether in the pediatric or adult populations. Proposals of a sex difference in cognitive recovery from brain damage have also been controversial. Six hundred and thirty five "consecutive" cases with cortical focal lesions including cases of all ages and both sexes were reviewed. Aetiology of the lesion was determined for each case as was postlesion IQ. Risk was highly male prevalent in all age groups, with a predominance of cardiovascular aetiology explaining much of the adult male prevalence. However, several other aetiological categories were significantly male prevalent in juveniles (mitotic, traumatic, dysplasic) and adults (mitotic, traumatic). There was no sex difference in outcome (i.e., postlesion IQ) of these cortical brain lesions for the cohort as a whole, after statistical removal of the influence of lesion extent, aetiology and presence of epilepsy. Mechanisms potentially responsible for sex differences in prevalence, aetiology of brain damage, and recovery, are reviewed and discussed.     

Intellectual similarity of virtual twin pairs: Developmental trends

Virtual twins (VTs) are same-age unrelated siblings reared together from infancy who replicate twinship, but without the genetic relatedness. A 2005 report from the ongoing Fullerton Virtual Twin Study found an IQ intraclass correlation of .26 (p < .01, n = 113 pairs) and a within-pair difference of 13.22 IQ points. The average age of VTs in that study was 8.10 years (SD = 8.56, range: 4.01-54.84 years). An opportunity to retest members of 43 VT pairs, 1.70-8.96 years after their time 1 assessment, allowed additional analyses of genetic and environmental influences underlying general intellectual development. A decrease in the VT IQ correlation and an increase in the within-pair difference were indicated, consistent with increasing genetic and/or non-shared environmental influences and decreasing shared environmental influence on general intellectual development throughout childhood.     

Neuropsychological sequelae of stroke as a function of handedness.

The preservation of visuospatial ability relative to verbal ability following right middle cerebral artery stroke was assessed in 19 left- and 19 right-handed male patients who were group-matched on the basis of age, education, and time elapsed since stroke. Analysis of covariance (covarying education) indicated that the left- and right-handed groups were significantly different with regard to the discrepancy between Verbal IQ and Performance IQ, with the left-handed patients showing a smaller difference than the right-handers. These results provide further evidence that sinistrality may be associated with less hemispheric specialization.     

Training of School Psychologists in Neuropsychology and Brain Injury: Results of a National Survey of Training Programs

A previous study evaluating receptive language after unilateral brain damage in childhood hypothesized lateralized attention and memory deficits without direct measurement. Our study directly measured attention, memory, and language in order to evaluate empirically the severity and laterality of sequelae. The performances of 11 individuals with a unilateral ischemic-lesion (7 right and 4 left hemisphere) were compared to controls matched on age, sex, and socioeconomic status. Results suggest subtle but persistent deficits in verbal memory, functional memory, and speed of processing after a lesion to either hemisphere. Lesions sustained before two years of age were associated with the lowest IQ scores. Our findings provide support for a configural representation of language that can to some extent compensate for inefficient or damaged components (Bates, 1994), and the middle-ground lateralization position (Thal et al., 1991) that asserts initial hemispheric specialization with the potential for reorganization.     

A parent-offspring adoption study of cognitive abilities in early childhood

Do cognitive abilities in early childhood relate genetically and/or environmentally to isomorphic abilities in adulthood? Are specific cognitive abilities diffentiated in early childhood in terms of their prediction of adult cognitive abilities? The present study, the first behavioral genetic analysis of specific cognitive abilities in early childhood, explored these questions using parent-offspring data for 186 adopted children and 151 nonadopted children tested in the longitudinal Colorado Adoption Project at 3 years of age and 162 adopted children and 138 nonadopted children tested at 4 years. The children's Stanford-Binet IQ and scores for four specific cognitive abilities (verbal, spatial, perceptual speed, and memory) were correlated with corresponding measures for their parents—the biological and adoptive parents of the adopted children and the natural parents of the nonadopted children. Significant correlations were found between biological mothers' IQ and the IQ of their adopted away offspring at 3 and 4 years of age, suggesting genetic influence for IQ. However, specific cognitive abilities yielded no significant correlations between biological mothers and their adopted-away offspring. These results suggest that substantial genetic continuity exists for IQ from early childhood to adulthood, but not for specific cognitive abilities.     

The effect of IQ level on the degree of cognitive deterioration experienced during acute hypoglycemia in normal humans

Acute hypoglycemia provokes a deterioration in cognitive function both in normal individuals and patients with Type 1 diabetes. A large interindividual variation is observed in the magnitude of the cognitive dysfunction observed during hypoglycemia, the reasons for which are not apparent. This study examines whether IQ level exerts a differential effect on the impairment of cognitive performance induced during acute hypoglycemia. Twenty-four nondiabetic participants were divided into high and average IQ groups according to their results on the Alice Heim 4 test and the National Adult Reading Test. Cognitive function was assessed during hypoglycemia using the following cognitive test battery: Paced Auditory Serial Addition Test (PASAT), Rapid Visual Information Processing (RVIP), Trail-Making B (TMB), Digit Symbol Substitution Test (DSST), and Four-Choice Reaction Time (CRT). In Condition A (the placebo condition), the participants' blood glucose was maintained at 4.5 mmol/1 throughout. On two occasions (Conditions B and C), the blood glucose was stabilized at 4.5 mmol/1 for 30 min, lowered to 2.5 mmol/1 (hypoglycemia) for 60 min, and restored to 4.5 mmol/1 for 30 min. Under each condition, the cognitive test battery was performed immediately after stabilization of blood glucose at 4.5 mmol/1, and the battery was repeated as follows: Condition A—after a further 40 min of euglycemia; Condition B—after 5 min of hypoglycemia; Condition C—after 40 min of hypoglycemia. Multivariate analysis of variance demonstrated a detoriation in cognitive performance as a result of hypoglycemia irrespective of IQ group (p< .005). Acute hypoglycemia induced a significant deterioration in cognitive function in all tests except TMB (p< .05). No overall effect of IQ on deterioration in cognitive performance could be ascertained, although univariate analysis of variance revealed an IQ effect on two of the test: The avergae IQ group deteriorated significantly less than the higher IQ group during hypoglycemia in the 4-s PASAT task (p = .03) and tended to have higher false alarm rates in the RVIP (p = .06). In conclusion, individuals with a higher IQ do not appear to be protected from tge adverse effects of acute hypoglycemia on cognitive function.     

Pendular energy transduction in the different phases of gait cycle in post-stroke subjects

MainTo analyze spatiotemporal gait parameters and the body center of mass (CoM) energy transduction at self-selected speed walking in a group of older patients with stroke.MethodsA cross-sectional study, fifteen subjects with 4.06 years post ̵stroke hemiparesis (eleven men and four women) and fifteen healthy subjects (four men and eleven women) participate in this study. Pendulum-like determining variables; Recovery (R) and Congruity percentage (%Cong) were analyzed in addition to immediate pendular re-conversion (Rint) during the phases in which the gait cycle is usually divided in clinical evaluations.ResultsHealthy subjects walked faster that stroke group (p = 0.001). %Cong was significantly higher in post-stroke respect to healthy subjects (p = 0.05). Rint showed significant differences between the groups for all phases (p = 0.05). The relation between speed and R was confirmed, for healthy (r = 0.67, p = 0.006) and post-stroke subjects (r = 0.851, p = 0.001), %Cong y Rint (r = −0.79, p = 0.001), (r = −0.93, p = 0.001) and periods of double support (r = −0.76, p = 0.001), (r = 0.69, p = 0.004) respectively.ConclusionAlteration of pendular mechanism in subjects post-stroke is associated mainly with energy transduction; mechanical energy recovered during double support phases in healthy and post-stroke subjects follows a different trend, in post-stroke subjects, a longer duration of the double support is associated with less energy loss.     

Clinical,Sociobiological, and Cognitive Predictors of ADHD Persistence in Children Followed Prospectively Over Time

With increasing awareness that ADHD is chronically disabling, a burgeoning literature has examined childhood clinical indicators of ADHD persistence. This study investigates whether childhood factors reflecting biological risk and cognitive reserve have additive predictive value for the persistence of ADHD that is unique beyond childhood indicators of disorder severity. One-hundred thirty children with ADHD (mean age = 8.9 years, 75 % male) were followed into adolescence (mean age = 14.0 years). Childhood ADHD and co-morbidities were assessed via interviews with parents and teachers; parental psychopathology was assessed via parent interview; exposure to neurobiological and psychosocial adversity were indexed by parent questionnaire; and cognitive reserve was evaluated through children’s performance on measures of IQ and executive functioning. Univariate analyses identified childhood inattention and hyperactivity-impulsivity, co-morbid oppositional defiant disorder, overall impairment, and paternal anxiety and depression as more prevalent amongst adolescents with persistent compared with remitted ADHD. Only child-level predictors remained significant in a final multivariate model. These results suggest that children who are most likely to experience persistent ADHD have a more severe clinical presentation in childhood, reflected by increased levels of inattention, oppositional behavior, and impairment. They also are more likely to have fathers with internalizing concerns, but these concerns do not uniquely predict ADHD persistence beyond child-level factors. Contrary to expectations, childhood adversity and cognitive functioning did not predict the course of ADHD.     

Atypical speech lateralization in adults with developmental coordination disorder demonstrated using functional transcranial Doppler ultrasound

Research using clinical populations to explore the relationship between hemispheric speech lateralization and handedness has focused on individuals with speech and language disorders, such as dyslexia or specific language impairment (SLI). Such work reveals atypical patterns of cerebral lateralization and handedness in these groups compared to controls. There are few studies that examine this relationship in people with motor coordination impairments but without speech or reading deficits, which is a surprising omission given the prevalence of theories suggesting a common neural network underlying both functions. We use an emerging imaging technique in cognitive neuroscience; functional transcranial Doppler (fTCD) ultrasound, to assess whether individuals with developmental coordination disorder (DCD) display reduced left‐hemisphere lateralization for speech production compared to control participants. Twelve adult control participants and 12 adults with DCD, but no other developmental/cognitive impairments, performed a word‐generation task whilst undergoing fTCD imaging to establish a hemispheric lateralization index for speech production. All participants also completed an electronic peg‐moving task to determine hand skill. As predicted, the DCD group showed a significantly reduced left lateralization pattern for the speech production task compared to controls. Performance on the motor skill task showed a clear preference for the dominant hand across both groups; however, the DCD group mean movement times were significantly higher for the non‐dominant hand. This is the first study of its kind to assess hand skill and speech lateralization in DCD. The results reveal a reduced leftwards asymmetry for speech and a slower motor performance. This fits alongside previous work showing atypical cerebral lateralization in DCD for other cognitive processes (e.g., executive function and short‐term memory) and thus speaks to debates on theories of the links between motor control and language production.     

Risk- and protective factors for memory plasticity in aging

ABSTRACT

Risk and protective factors for cognitive function in aging may affect how much individuals benefit from their environment or life experiences by preserving or improving cognitive abilities. We investigated the relations between such factors and outcome from episodic-memory training in 136 healthy young and older adults. Tested risk factors included carrying the ?4 variant of the apolipoprotein E allele (APOE), age, body mass index, blood pressure, and cholesterol. Protective factors included higher levels of education, intelligence quotient (IQ), physical activity, fatty acids, and vitamin D. Average increases in memory performance were seen after training, with ample variation between individuals. Being young, female, and having higher IQ were positive predictors of memory improvement. No other relationships were observed. Similar benefit was observed across APOE allelic variation. This indicates that beyond IQ, age, and sex, known risk -and protective factors of cognitive function in aging were not significantly related to memory plasticity.     

What Does the DAP:IQ Measure?: Drawing Comparisons between Drawing Performance and Developmental Assessments

Human figure drawing tasks such as the Draw-a-Person test have long been used to assess intelligence (F. Goodenough, 1926). The authors investigate the skills tapped by drawing and the risk factors associated with poor drawing. Self-portraits of 345 preschool children were scored by raters trained in using the Draw-a-Person Intellectual Ability test (DAP:IQ) rubric (C. R. Reynolds & J. A. Hickman, 2004). Analyses of children's fine motor, gross motor, social, cognitive, and language skills revealed that only fine motor skill was an independent predictor of DAP:IQ scores. Being a boy and having a low birth weight were associated with lower DAP:IQ scores. These findings suggest that although the DAP:IQ may not be a valid measure of cognitive ability, it may be a useful screening tool for fine motor disturbances in at-risk children, such as boys who were born at low birth weights. Furthermore, researchers who use human figure drawing tasks to measure intelligence should measure fine motor skill in addition to intelligence.     

A Quantitative Trait Locus Associated With Cognitive Ability in Children

Quantitative trait loci (QTLs) associated with general cognitive ability ( g ) were investigated for several groups of children selected for very high or for average cognitive functioning. A DNA marker in the gene for insulin-like growth factor-2 receptor (IGF2R) on Chromosome 6 yielded a significantly greater frequency of a particular form of the gene (allele) in a high- g group (.303; average IQ = 136, N = 51) than in a control group (.156; average IQ = 103, N = 51). This association was replicated in an extremely-high- g group (all estimated IQs > 160, N = 52) as compared with an independent control group (average IQ = 101, N = 50), with allelic frequencies of .340 and .169, respectively. Moreover, a high-mathematics-ability group ( N = 62) and a high-verbal-ability group ( N = 51) yielded results that were in the same direction but only marginally significant ( p = .06 and .08, respectively).     

Recycling,evolution and the structure of human personality

Lower childhood cognitive ability may be a risk factor for greater cognitive decline in late life and progression to dementia. To assess variation in age-related cognitive change, it is helpful to have valid measures of cognitive ability from early life. Here, we examine the relation between childhood intelligence and cognitive change in later life in two samples, one born in 1921 and the other in 1936. All participants completed the same test of mental ability (one of the Moray House Test series) at age about 11 years, and were re-examined on Raven’s Progressive Matrices at age 77 (1921-born) or age 64 (1936-born). Where possible, the 1921 sample was re-tested at the age of about 80 years old and the 1936 sample re-tested at about 66 years. After taking into account various covariates, including sex, education and occupation, childhood intelligence was a significant predictor of cognitive change in later life. Results were in the direction that participants with lower childhood mental ability experienced relatively greater cognitive decline, whereas those of higher childhood mental ability showed improved performance. This result suggests that higher premorbid cognitive ability is protective of decline in later life.