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This study investigated the relations of tectal volume and superior parietal cortex, as well as alterations in tectocortical white matter connectivity, with the orienting and executive control attention networks in individuals with spina bifida myelomeningocele (SBM). Probabilistic diffusion tractography and quantification of tectal and superior parietal cortical volume were performed on 74 individuals aged 8-29 with SBM and a history of hydrocephalus. Behavioral assessments measured posterior (covert orienting) and anterior (conflict resolution, attentional control) attention network functions. Reduced tectal volume was associated with slower covert orienting; reduced superior parietal cortical volume was associated with slower conflict resolution; and increased axial diffusivity and radial diffusivity along both frontal and parietal tectocortical pathways were associated with reduced attentional control. Results suggest that components of both the orienting and executive control attention networks are impaired in SBM. Neuroanatomical disruption to the orienting network appears more robust and a direct consequence of characteristic midbrain dysmorphology; whereas, executive control difficulties may emerge from parietal cortical anomalies and reduced frontal and parietal cortical-subcortical white matter pathways susceptible to the pathophysiological effects of congenital hydrocephalus.

Individuals with spina bifida myelomeningocele (SBM) exhibit brain abnormalities in cortical thickness, white matter integrity, and cerebellar structure. Little is known about deep gray matter macro- and microstructure in this population. The current study utilized volumetric and diffusion-weighted MRI techniques to examine gray matter volume and microstructure in several subcortical structures: basal ganglia nuclei, thalamus, hippocampus, and amygdala. Sixty-six children and adolescents (ages 8-18; M = 12.0, SD = 2.73) with SBM and typically developing (TD) controls underwent T1- and diffusion-weighted neuroimaging. Microstructural results indicated that hippocampal volume was disproportionately reduced, whereas the putamen volume was enlarged in the group with SBM. Microstructural analyses indicated increased mean diffusivity (MD) and fractional anisotropy (FA) in the gray matter of most examined structures (i.e., thalamus, caudate, hippocampus), with the putamen exhibiting a unique pattern of decreased MD and increased FA. These results provide further support that SBM differentially disrupts brain regions whereby some structures are volumetrically normal whereas others are reduced or enlarged. In the hippocampus, volumetric reduction coupled with increased MD may imply reduced cellular density and aberrant organization. Alternatively, the enlarged volume and significantly reduced MD in the putamen suggest increased density.

We studied three forms of dyadic communication involving theory of mind (ToM) in 82 children with traumatic brain injury (TBI) and 61 children with orthopedic injury (OI): Cognitive (concerned with false belief), Affective (concerned with expressing socially deceptive facial expressions), and Conative (concerned with influencing another's thoughts or feelings). We analyzed the pattern of brain lesions in the TBI group and conducted voxel-based morphometry for all participants in five large-scale functional brain networks, and related lesion and volumetric data to ToM outcomes. Children with TBI exhibited difficulty with Cognitive, Affective, and Conative ToM. The perturbation threshold for Cognitive ToM is higher than that for Affective and Conative ToM, in that Severe TBI disturbs Cognitive ToM but even Mild-Moderate TBI disrupt Affective and Conative ToM. Childhood TBI was associated with damage to all five large-scale brain networks. Lesions in the Mirror Neuron Empathy network predicted lower Conative ToM involving ironic criticism and empathic praise. Conative ToM was significantly and positively related to the package of Default Mode, Central Executive, and Mirror Neuron Empathy networks and, more specifically, to two hubs of the Default Mode Network, the posterior cingulate/retrosplenial cortex and the hippocampal formation, including entorhinal cortex and parahippocampal cortex., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Objective: To assess the phenomenology and predictive factors of attention-deficit/hyperactivity disorder (ADHD) after traumatic brain injury (TBI), also called secondary ADHD (SADHD)., Method: Children without preinjury ADHD 5-14 years old with TBI from consecutive admissions (n = 143) to five trauma centers were observed prospectively from 6 to 12 months (12-month assessment) and from 12 to 24 months (24-month assessment) postinjury with semistructured psychiatric interviews. Injury and preinjury psychosocial variables were assessed., Results: SADHD occurred in 15 of 103 (15%) of participants between 6 and 12 months after injury and 17 of 82 (21%) in the second year after injury. SADHD was significantly (p < .05) comorbid with personality change due to TBI and new-onset disruptive behavior disorders. Preinjury adaptive function was a consistent predictor of SADHD. Regression analyses revealed that preinjury psychosocial adversity was an independent predictor of SADHD in the second year after injury. Neither severity of injury nor lesion location predicted SADHD from 6 to 24 months postinjury., Conclusions: Determination of preinjury psychosocial adversity and the child's preinjury functioning during the index hospitalization would improve identification of children at highest risk of development of SADHD.

Objective: To assess the phenomenology and predictive factors of attention-deficit/hyperactivity disorder (ADHD) after traumatic brain injury (TBI), also called secondary ADHD (SADHD)., Method: Children without preinjury ADHD 5-14 years old with TBI from consecutive admissions (n = 143) to five trauma centers were observed prospectively for 6 months (baseline and 6 months), with semistructured psychiatric interviews. Injury severity, lesion characteristics, and preinjury variables including psychiatric disorder, family psychiatric history, family psychiatric history of ADHD, family function, socioeconomic status, psychosocial adversity, and adaptive function were assessed with standardized instruments., Results: SADHD in the first 6 months after injury occurred in 18 of 115 (16%) of returning participants. All subtypes of ADHD occurred. Socioeconomic status (p = .041) and orbitofrontal gyrus lesions (p = .005) independently significantly predicted SADHD., Conclusions: These findings are consistent with research on developmental ADHD that implicate psychosocial factors and prefrontal structural and functional differences between those with and without the disorder.

Idioms are phrases with figurative meanings that are not directly derived from the literal meanings of the words in the phrase. Idiom comprehension varies with: literality, whether the idiom is literally plausible; compositionality, whether individual words contribute to a figurative meaning; and contextual bias. We studied idiom comprehension in children with spina bifida meningomyelocele (SBM), a neurodevelopmental disorder associated with problems in discourse comprehension and agenesis and hypoplasia of the corpus callosum. Compared to age peers, children with SBM understood decomposable idioms (which are processed more like literal language) but not non-decomposable idioms (which require contextual analyses for acquisition). The impairment in non-decomposable idioms was related to congenital agenesis of the corpus callosum, which suggests that the consequences of impaired interhemispheric communication, whether congenital or acquired in adulthood, are borne more by configurational than by compositional language.

Objective: To assess the phenomenology and predictive factors of personality change due to traumatic brain injury., Method: Children (N = 177), aged 5 to 14 years with traumatic brain injury from consecutive admissions to five trauma centers, were followed prospectively at baseline and 6 months with semistructured psychiatric interviews. Injury severity, lesion characteristics, and preinjury variables including psychiatric disorder, family psychiatric history, family function, socioeconomic status, psychosocial adversity, and adaptive function were assessed with standardized instruments., Results: Personality change occurred in 22% of participants in the first 6 months after injury. Severity of injury predicted personality change, whereas none of the psychosocial variables predicted personality change. Lesions of the dorsal prefrontal cortex, specifically the superior frontal gyrus, were associated with personality change after controlling for severity of injury or the presence of other lesions., Conclusions: These findings are consistent with models of affective dysregulation that implicate a dorsal prefrontal cortex system important for effortful regulation of affective states.

Text comprehension processes were investigated in children with hydrocephalus, a neurodevelopmental disorder associated with good word decoding, but deficient reading comprehension. In Experiment 1, hydrocephalus and control groups were similar in processes related to activating word meanings and using context to enhance meaning. The hydrocephalus group was poorer at suppressing contextually irrelevant meanings. In Experiment 2, the hydrocephalus group had difficulty integrating information from an earlier read sentence to understand a new sentence as textual distance between the two propositions increased, suggesting difficulty in reactivation processes related to comprehension. Results are discussed in relation to cognitive and neurocognitive models of comprehension.

Acquired cerebellar lesions are associated with motor speech deficits. Spina bifida with hydrocephalus (SBH) is a neurodevelopmental disorder that involves significant dysmorphology of the cerebellum. Videotaped narratives produced by 40 children and adults with SBH and their 40 age-matched controls were coded for three motor speech deficits: dysfluency, ataxic dysarthria (articulatory inaccuracy, prosodic excess, and phonatory-prosodic insufficiency) (Brown, Darley, & Aronson, 1970; Darley, Aronson, & Brown, 1969a), and speech rate. Individuals with SBH had more motor speech deficits than controls. Dysfluency was related to an interaction between chronological age and SBH. Speech rate was related independently to chronological age and SBH. Ataxic dysarthria was related to the biology of SBH, and was associated with both physical phenotype (level of spinal cord lesion) and medical history (number of shunt revisions). The data show that developmental as well as acquired lesions of the cerebellum disrupt motor speech, and add to the developmental role of the cerebellum in the automatization of motor skills, including speech., (Copyright 2002 Elsevier Science (USA).)