Marsh Königs

Physical exercise and executive functions in preadolescent children, adolescents and young adults: a meta-analysis

Purpose The goal of this meta-analysis was to aggregate available empirical studies on the effects of physical exercise on executive functions in preadolescent children (6–12 years of age), adolescents (13–17 years of age) and young adults (18–35 years of age). Method The electronic databases PubMed, EMBASE and SPORTDiscus were searched for relevant studies reporting on the effects of physical exercise on executive functions. Nineteen studies were selected. Results There was a significant overall effect of acute physical exercise on executive functions (d=0.52, 95% CI 0.29 to 0.76, p<0.001). There were no significant differences between the three age groups (Q (2)=0.13, p=0.94). Furthermore, no significant overall effect of chronic physical exercise (d=0.14, 95%CI −0.04 to 0.32, p=0.19) on executive functions (Q (1)=5.08, p<0.05) was found. Meta-analytic effect sizes were calculated for the effects of acute physical exercise on the domains inhibition/interference control (d=0.46, 95% CI 0.33 to 0.60, p<0.001) and working memory (d=0.05, 95% CI  −0.51 to 0.61, p=0.86) as well as for the effects of chronic physical exercise on planning (d=0.16, 95% CI 0.18 to 0.89, p=0.18). Conclusions Results suggest that acute physical exercise enhances executive functioning. The number of studies on chronic physical exercise is limited and it should be investigated whether chronic physical exercise shows effects on executive functions comparable to acute physical exercise. This is highly relevant in preadolescent children and adolescents, given the importance of well-developed executive functions for daily life functioning and the current increase in sedentary behaviour in these age groups.

Predictive value of the Bayley Scales of Infant Development on development of very preterm/very low birth weight children: A meta-analysis

BACKGROUND AND AIMS The Bayley scales of infant development (BSID) is the most widely used measure to assess neurodevelopment of very preterm (gestational age ≤32 weeks) and very low birth weight (VLBW, ≤1500 g) infants in the first three years of life. This meta-analysis determines the predictive value of the mental developmental index (MDI) and the psychomotor developmental index (PDI)/motor composite, collectively referred to as Bayley motor scale, of the BSID-I, -II and Bayley-III for later cognitive and motor functioning in very preterm/VLBW children. METHODS Cochrane Library, PubMed, PsychINFO and CINAHL were searched for English-language peer-reviewed studies published before March 2013. Studies were included if they reported odds ratios or correlations between the MDI or Bayley motor scale scores obtained in the first three years of life, and standardized cognitive or motor assessment obtained later in life in very preterm/VLBW children. Meta-analytic methods were applied to aggregate available data. RESULTS A total of 16 studies met inclusion criteria. Across 14 studies (n=1330 children), MDI scores were strongly predictive for later cognitive functioning, r=0.61 (95% CI: 0.57-0.64), explained variance 37%, p<.001. The relationship between MDI scores and later cognitive function was not mediated by birth weight (p=.56), gestational age (p=.70), and time interval between assessments (p=.55). Across five studies (n=555 children), Bayley motor scale scores were moderately predictive for later motor function, r=0.34 (95% CI: 0.26-0.42), explained variance 12%, p<.001. CONCLUSIONS In very preterm/VLBW children, MDI scores explain 37% of the variance in later cognitive functioning, whereas Bayley motor scale scores explain 12% of later motor function. Thus a large proportion of the variance remains unexplained, underlining the importance of enhancing prediction of developmental delay in very preterm children.

Pediatric Traumatic Brain Injury and Attention Deficit

BACKGROUND: We investigated the impact of pediatric traumatic brain injury (TBI) on attention, a prerequisite for behavioral and neurocognitive functioning. METHODS: Children aged 6 to 13 years who were diagnosed with TBI (n = 113; mean 1.7 years postinjury) were compared with children with a trauma control injury (not involving the head) (n = 53). TBI severity was defined as mild TBI with or without risk factors for complicated TBI (mildRF+ TBI, n = 52; mildRF− TBI, n = 24) or moderate/severe TBI (n = 37). Behavioral functioning was assessed by using parent and teacher questionnaires, and the Attention Network Test assessed alerting, orienting, and executive attention. Ex-Gaussian modeling determined the contribution of extremely slow responses (lapses of attention) to mean reaction time (MRT). RESULTS: The TBI group showed higher parent and teacher ratings of attention and internalizing problems, higher parent ratings of externalizing problems, and lower intelligence than the control group (P < .05, d ≥ 0.34). No effect of TBI on alerting, orienting, and executive attention was observed (P ≥ .55). MRT was slower in the TBI group (P = .008, d = 0.45), traced back to increased lapses of attention (P = .002, d = 0.52). The mildRF− TBI group was unaffected, whereas the mildRF+ TBI and moderate/severe TBI groups showed elevated parent ratings of behavior problems, lower intelligence, and increased lapses of attention (P ≤ .03, d ≥ 0.48). Lapses of attention fully explained the negative relation between intelligence and parent-rated attention problems in the TBI group (P = .02). CONCLUSIONS: Lapses of attention represent a core attention deficit in children with mildRF+ TBI (even in the absence of intracranial pathology) or moderate/severe TBI, and relate to daily life problems after pediatric TBI.

Post-traumatic amnesia predicts intelligence impairment following traumatic brain injury: a meta-analysis

Context Worldwide, millions of patients with traumatic brain injury (TBI) suffer from persistent and disabling intelligence impairment. Post-traumatic amnesia (PTA) duration is a promising predictor of intelligence following TBI. Objectives To determine (1) the impact of TBI on intelligence throughout the lifespan and (2) the predictive value of PTA duration for intelligence impairment, using meta-analytic methods. Methods Electronic databases were searched for peer reviewed articles, published until February 2012. Studies reporting intelligence following TBI and injury severity by PTA duration were included. Meta-analytic methods generated effect sizes for full scale IQ (FSIQ), performance IQ (PIQ) and verbal IQ (VIQ), following mild TBI (PTA duration 1–24 h) and severe TBI (PTA duration >7 days), during the subacute phase of recovery (≤6 months post-injury) and the chronic phase (>6 months post-injury). Meta-regression elucidated the predictive value of PTA duration for intelligence impairment. Results Patients with severe TBI exhibited large depressions in FSIQ in the subacute phase of recovery (d=−1.07, 95% CI to 1.52 to −0.62; p<0.001), persisting into the chronic phase (d=−0.78, 95% CI −1.06 to −0.51; p<0.001). PIQ was more severely affected than VIQ in the subacute phase (Q(1) =3.85; p<0.05) but not in the chronic phase (Q(1) =0.03, p=0.87). Most importantly, longer PTA duration strongly predicted greater depressions of FSIQ and PIQ in the subacute phase (−0.76 ≤ βs ≤ −0.73, Ps<0.01) and FSIQ, PIQ and VIQ in the chronic phase (−0.80 ≤ βs ≤ −0.61, Ps<0.05). Conclusions PTA duration is a valuable predictor of intelligence impairment following TBI. Results support the routine assessment of PTA duration in clinical settings.

Intelligence after traumatic brain injury: meta-analysis of outcomes and prognosis

Worldwide, 54–60 million individuals sustain traumatic brain injury (TBI) each year. This meta‐analysis aimed to quantify intelligence impairments after TBI and to determine the value of age and injury severity in the prognosis of TBI. An electronic database search identified 81 relevant peer‐reviewed articles encompassing 3890 patients. Full‐scale IQ (FSIQ), performance IQ (PIQ) and verbal IQ (VIQ) impairments were quantified (Cohens d) for patients with mild, moderate and severe TBI in the subacute phase of recovery and the chronic phase. Meta‐regressions explored prognostic values of age and injury severity measures for intelligence impairments. The results showed that, in the subacute phase, FSIQ impairments were absent for patients with mild TBI, medium‐sized for patients with moderate TBI (d = −0.61, P < 0.001) and large for patients with severe TBI (d = −1.09, P < 0.001). In the chronic phase, FSIQ impairments were small for patients with mild or moderate TBI (d = −0.37 and −0.19, P ≤ 0.008) and large for patients with severe TBI (d = −0.80, P < 0.001). Adults with mild TBI had larger PIQ and VIQ impairments in the chronic phase than children (both Q ≥ 5.21, P ≤ 0.02), whilst children with severe TBI had larger FSIQ and VIQ impairments than adults (both Q ≥ 4.40, P ≤ 0.04). Glasgow Coma Scale score, duration of loss of consciousness and post‐traumatic amnesia duration moderately to strongly predicted FSIQ, PIQ and VIQ impairments (0.41 ≤ r ≤ 0.82, P ≤ 0.02), but no differences in predictive value were observed. In conclusion, TBI causes persisting intelligence impairments, where children may have better recovery from mild TBI and poorer recovery from severe TBI than adults. Injury severity measures predict intelligence impairments and do not outperform one another.

Impaired Visual Integration in Children with Traumatic Brain Injury: An Observational Study.

Background Axonal injury after traumatic brain injury (TBI) may cause impaired sensory integration. We aim to determine the effects of childhood TBI on visual integration in relation to general neurocognitive functioning. Methods We compared children aged 6–13 diagnosed with TBI (n = 103; M = 1.7 years post-injury) to children with traumatic control (TC) injury (n = 44). Three TBI severity groups were distinguished: mild TBI without risk factors for complicated TBI (mildRF- TBI, n = 22), mild TBI with ≥1 risk factor (mildRF+ TBI, n = 46) or moderate/severe TBI (n = 35). An experimental paradigm measured speed and accuracy of goal-directed behavior depending on: (1) visual identification; (2) visual localization; or (3) both, measuring visual integration. Group-differences on reaction time (RT) or accuracy were tracked down to task strategy, visual processing efficiency and extra-decisional processes (e.g. response execution) using diffusion model analysis. General neurocognitive functioning was measured by a Wechsler Intelligence Scale short form. Results The TBI group had poorer accuracy of visual identification and visual integration than the TC group (Ps ≤ .03; ds ≤ -0.40). Analyses differentiating TBI severity revealed that visual identification accuracy was impaired in the moderate/severe TBI group (P = .05, d = -0.50) and that visual integration accuracy was impaired in the mildRF+ TBI group and moderate/severe TBI group (Ps < .02, ds ≤ -0.56). Diffusion model analyses tracked impaired visual integration accuracy down to lower visual integration efficiency in the mildRF+ TBI group and moderate/severe TBI group (Ps < .001, ds ≤ -0.73). Importantly, intelligence impairments observed in the TBI group (P = .009, d = -0.48) were statistically explained by visual integration efficiency (P = .002). Conclusions Children with mildRF+ TBI or moderate/severe TBI have impaired visual integration efficiency, which may contribute to poorer general neurocognitive functioning.

Pediatric Traumatic Brain Injury Affects Multisensory Integration

Objective: To investigate the impact of pediatric traumatic brain injury (TBI) on multisensory integration in relation to general neurocognitive functioning. Method: Children with a hospital admission for TBI aged between 6 and 13 years (n = 94) were compared with children with trauma control (TC) injuries (n = 39), while differentiating between mild TBI without risk factors for complicated TBI (mildRF−; n = 19), mild TBI with ≥1 risk factor (mildRF+; n = 45), and moderate/severe TBI (n = 30). We measured set-shifting performance based on visual information (visual shift condition) and set-shifting performance based on audiovisual information, requiring multisensory integration (audiovisual shift condition). Effects of TBI on set-shifting performance were traced back to task strategy (i.e., boundary separation), processing efficiency (i.e., drift rate), or extradecisional processes (i.e., nondecision time) using diffusion model analysis. General neurocognitive functioning was measured using estimated full-scale IQ (FSIQ). Results: The TBI group showed selectively reduced performance in the audiovisual shift condition (p = .009, Cohen’s d = −0.51). Follow-up analyses in the audiovisual shift condition revealed reduced performance in the mildRF+ TBI group and moderate/severe TBI group (ps ⩽ .025, ds ⩽ −0.61). These effects were traced back to lower drift rate (ps ⩽ .048, ds ⩽ −0.44), reflecting reduced multisensory integration efficiency. Notably, accuracy and drift rate in the audiovisual shift condition partially mediated the relation between TBI and FSIQ. Conclusion: Children with mildRF+ or moderate/severe TBI are at risk for reduced multisensory integration efficiency, possibly contributing to decreased general neurocognitive functioning.

The Structural Connectome of Children With Traumatic Brain Injury

This study aimed to investigate the impact of mild to severe pediatric TBI on the structural connectome. Children aged 8–14 years with trauma control (TC) injury (n = 27) were compared to children with mild TBI and risk factors for complicated TBI (mildRF+, n = 20) or moderate/severe TBI (n = 16) at 2.8 years post‐injury. Probabilistic tractography on diffusion tensor imaging data was used in combination with graph theory to study structural connectivity. Functional outcome was measured using neurocognitive tests and parent and teacher questionnaires for behavioral functioning. The results revealed no evidence for an impact of mildRF+ TBI on the structural connectome. In contrast, the moderate/severe TBI group showed longer characteristic path length (P = 0.022, d = 0.82) than the TC group. Furthermore, longer characteristic path length was related to poorer intelligence and poorer working memory in children with TBI. In conclusion, children have abnormal organization of the structural connectome after moderate/severe TBI, which may be implicated in neurocognitive dysfunction associated with pediatric TBI. These findings should be interpreted in the context of our exploratory analyses, which indicate that the definition and weighting of connectivity (e.g., streamline density, fractional anisotropy) influence the properties of the reconstructed connectome and its sensitivity to the impact and outcome of pediatric TBI. Hum Brain Mapp 38:3603–3614, 2017.

The child's perspective on discomfort during medical research procedures: a descriptive study

Objective The evaluation of discomfort in paediatric research is scarcely evidence-based. In this study, we make a start in describing childrens self-reported discomfort during common medical research procedures and compare this with discomfort during dental check-ups which can be considered as a reference level of a ‘minimal discomfort’ medical procedure. We exploratory study whether there are associations between age, anxiety-proneness, gender, medical condition, previous experiences and discomfort. We also describe childrens suggestions for reducing discomfort. Design Cross-sectional descriptive study. Setting Paediatric research at three academic hospitals. Patients 357 children with and without illnesses (8–18 years, mean=10.6 years) were enrolled: 307 from paediatric research studies and 50 from dental care. Main outcome measures We measured various generic forms of discomfort (nervousness, annoyance, pain, fright, boredom, tiredness) due to six common research procedures: buccal swabs, MRI scans, pulmonary function tests, skin prick tests, ultrasound imaging and venepunctures. Results Most children reported limited discomfort during the research procedures (means: 1–2.6 on a scale from 1 to 5). Compared with dental check-ups, buccal swab tests, skin prick tests and ultrasound imaging were less discomforting, while MRI scans, venepunctures and pulmonary function tests caused a similar degree of discomfort. 60.3% of the children suggested providing distraction by showing movies to reduce discomfort. The exploratory analyses suggested a positive association between anxiety-proneness and discomfort. Conclusions The findings of this study support the acceptability of participation of children in the studied research procedures, which stimulates evidence-based research practice. Furthermore, the present study can be considered as a first step in providing benchmarks for discomfort of procedures in paediatric research.

Feedback learning and behavior problems after pediatric traumatic brain injury

BACKGROUND Feedback learning is essential for behavioral development. We investigated feedback learning in relation to behavior problems after pediatric traumatic brain injury (TBI). METHOD Children aged 6-13 years diagnosed with TBI (n = 112; 1.7 years post-injury) were compared with children with traumatic control (TC) injury (n = 52). TBI severity was defined as mild TBI without risk factors for complicated TBI (mildRF- TBI, n = 24), mild TBI with ⩾1 risk factor for complicated TBI (mildRF+ TBI, n = 51) and moderate/severe TBI (n = 37). The Probabilistic Learning Test was used to measure feedback learning, assessing the effects of inconsistent feedback on learning and generalization of learning from the learning context to novel contexts. The relation between feedback learning and behavioral functioning rated by parents and teachers was explored. RESULTS No evidence was found for an effect of TBI on learning from inconsistent feedback, while the moderate/severe TBI group showed impaired generalization of learning from the learning context to novel contexts (p = 0.03, d = -0.51). Furthermore, the mildRF+ TBI and moderate/severe TBI groups had higher parent and teacher ratings of internalizing problems (ps ⩽ 0.04, ds ⩾ 0.47) than the TC group, while the moderate/severe TBI group also had higher parent ratings of externalizing problems (p = 0.006, d = 0.58). Importantly, poorer generalization of learning predicted higher parent ratings of externalizing problems in children with TBI (p = 0.03, β = -0.21) and had diagnostic utility for the identification of children with TBI and clinically significant externalizing behavior problems (area under the curve = 0.77, p = 0.001). CONCLUSIONS Moderate/severe pediatric TBI has a negative impact on generalization of learning, which may contribute to post-injury externalizing problems.