Regional Topological Aberrances of White Matter- and Gray Matter-Based Functional Networks for Attention Processing May Foster Traumatic Brain Injury-Related Attention Deficits in Adults

Traumatic brain injury (TBI) is highly prevalent in adults. TBI-related functional brain alterations have been linked with common post-TBI neurobehavioral sequelae, with unknown neural substrates. This study examined the systems-level functional brain alterations in white matter (WM) and gray matter (GM) for visual sustained-attention processing, and their interactions and contributions to post-TBI attention deficits. Task-based functional MRI data were collected from 42 adults with TBI and 43 group-matched normal controls (NCs), and analyzed using the graph theoretic technique. Global and nodal topological properties were calculated and compared between the two groups. Correlation analyses were conducted between the neuroimaging measures that showed significant between-group differences and the behavioral symptom measures in attention domain in the groups of TBI and NCs, respectively. Significantly altered nodal efficiencies and/or degrees in several WM and GM nodes were reported in the TBI group, including the posterior corona radiata (PCR), posterior thalamic radiation (PTR), postcentral gyrus (PoG), and superior temporal sulcus (STS). Subjects with TBI also demonstrated abnormal systems-level functional synchronization between the PTR and STS in the right hemisphere, hypo-interaction between the PCR and PoG in the left hemisphere, as well as the involvement of systems-level functional aberrances in the PCR in TBI-related behavioral impairments in the attention domain. The findings of the current study suggest that TBI-related systems-level functional alterations associated with these two major-association WM tracts, and their anatomically connected GM regions may play critical role in TBI-related behavioral deficits in attention domains.

Developmental Language Disorder and the Assessment of Signed Language

In recent years, deaf and/or hard of hearing (D/HH) children with atypical signed language abilities have become the focus of attention by researchers and educators, especially clinicians in programs that focus on bilingual (signed-written/spoken) education. Studies have shown that Deaf children with a language disorder present with a myriad of linguistic challenges, including struggles with fingerspelling comprehension, complex morphology, or lexical processing. This chapter highlights methods commonly used in assessing children suspected of having a developmental signed language disorder. In addition, it outlines issues that are critical for working with D/HH children, such as considering the possible role of co-occurring disabilities (such as attention deficits and autism) and obtaining information and support from parents and educators/clinicians. Finally, the chapter outlines suggestions for researchers and clinicians working together to identify and provide intervention for children suspected of having a developmental signed language disorder.

Regional Topological Aberrances of White Matter- and Gray Matter-based Functional Networks for Attention Processing may Foster Traumatic Brain Injury-Related Attention Deficits in Adults

ABSTRACTTraumatic brain injury (TBI) is highly prevalent in adults. TBI-related functional brain alterations have been linked with common post-TBI neurobehavioral sequelae, with unknown neural sub-strates. This study examined the systems-level functional brain alterations in white matter (WM) and gray matter (GM) for visual sustained attention processing, their interactions, and contribution to post-TBI attention deficits. Task-based functional MRI data were collected from 42 adults with TBI and 43 group-matched normal controls (NCs), and analyzed using the graph theoretic tech-nique. Global and nodal topological properties were calculated and compared between the two groups. Correlation analyses were conducted between the neuroimaging measures that showed significant between-group differences and the behavioral symptom measures in attention domain in the groups of TBI and NCs, respectively. Significantly altered nodal efficiency and/or degree in several WM and GM nodes were reported in the TBI group, including the posterior corona radiata (PCR), posterior thalamic radiation (PTR), postcentral gyrus (PoG), and superior temporal sulcus (STS). Subjects with TBI also demonstrated abnormal systems-level functional synchronization between the PTR and STS in the right hemisphere, hypo-interaction between PCR and PoG in the left hemisphere; as well as the involvement of systems-level functional aberrances in PCR in TBI-related behavioral impairments in the attention domain. Findings of the current study suggest that TBI-related systems-level functional alterations associated with these two major association WM tracts and their anatomically connected GM regions may play critical role in TBI-related behavioral deficits in attention domain.

Eye-tracking study of joint attention deficits in pre-school age

The article investigates joint attention deficits in various forms of atypical development using eye movement recording. Preschoolers aged 5-7 years from different clinical groups participated in the study: typically developing (n = 20), with mental retardation (ICD-10 class F83) (n = 20), preschoolers with delayed speech development (ICD-10 class R47) (n = 20), with hearing impairment (sensorineural hearing loss, ICD-10 class H90) (n = 10) and with visual impairment (amblyopia and strabismus, IBC-10 class H53) (n = 20). Contrasting group analyses allowed us to identify both specific and universal manifestations of joint attention deficit symptoms in the different forms of atypical development. Gaze tracking was used to analyze fixation duration and frequency, fixation distribution, areas of interest, and to identify markers of joint attention deficits that interfere with the child's productive interaction with an adult. Potential mechanisms of atypical joint attention are described, including atypical direction of gaze, changes in the dynamics of the operative visual field, duration of visual concentration, and accuracy in fixing the object’s elements. It is shown that fixation time in joint attention episodes can be regarded as a prognostic marker of joint attention disorders: joint attention is associated not only with spatial characteristics of areas of interest, but also with fixation duration on the object (decrease/increase in fixation duration).

Abnormal Functional Network Topology and Its Dynamics during Sustained Attention Processing Significantly Implicate Post-TBI Attention Deficits in Children

Traumatic brain injury (TBI) is highly prevalent in children. Attention deficits are among the most common and persistent post-TBI cognitive and behavioral sequalae that can contribute to adverse outcomes. This study investigated the topological properties of the functional brain network for sustained attention processing and their dynamics in 42 children with severe post-TBI attention deficits (TBI-A) and 47 matched healthy controls. Functional MRI data during a block-designed sustained attention task was collected for each subject, with each full task block further divided into the pre-, early, late-, and post-stimulation stages. The task-related functional brain network was constructed using the graph theoretic technique. Then, the sliding-window-based method was utilized to assess the dynamics of the topological properties in each stimulation stage. Relative to the controls, the TBI-A group had significantly reduced nodal efficiency and/or degree of left postcentral, inferior parietal, inferior temporal, and fusiform gyri and their decreased stability during the early and late-stimulation stages. The left postcentral inferior parietal network anomalies were found to be significantly associated with elevated inattentive symptoms in children with TBI-A. These results suggest that abnormal functional network characteristics and their dynamics associated with the left parietal lobe may significantly link to the onset of the severe post-TBI attention deficits in children.